Merge branch 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux

Pull i2c-embedded changes from Wolfram Sang:
 - CBUS driver (an I2C variant)
 - continued rework of the omap driver
 - s3c2410 gets lots of fixes and gains pinctrl support
 - at91 gains DMA support
 - the GPIO muxer gains devicetree probing
 - typical fixes and additions all over

* 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux: (45 commits)
  i2c: omap: Remove the OMAP_I2C_FLAG_RESET_REGS_POSTIDLE flag
  i2c: at91: add dma support
  i2c: at91: change struct members indentation
  i2c: at91: fix compilation warning
  i2c: mxs: Do not disable the I2C SMBus quick mode
  i2c: mxs: Handle i2c DMA failure properly
  i2c: s3c2410: Remove recently introduced performance overheads
  i2c: ocores: Move grlib set/get functions into #ifdef CONFIG_OF block
  i2c: s3c2410: Add fix for i2c suspend/resume
  i2c: s3c2410: Fix code to free gpios
  i2c: i2c-cbus-gpio: introduce driver
  i2c: ocores: Add support for the GRLIB port of the controller and use function pointers for getreg and setreg functions
  i2c: ocores: Add irq support for sparc
  i2c: omap: Move the remove constraint
  ARM: dts: cfa10049: Add the i2c muxer buses to the CFA-10049
  i2c: s3c2410: do not special case HDMIPHY stuck bus detection
  i2c: s3c2410: use exponential back off while polling for bus idle
  i2c: s3c2410: do not generate STOP for QUIRK_HDMIPHY
  i2c: s3c2410: grab adapter lock while changing i2c clock
  i2c: s3c2410: Add support for pinctrl
  ...

27 files changed, 1480 insertions, 359 deletions

diff --git a/Documentation/devicetree/bindings/i2c/i2c-cbus-gpio.txt b/Documentation/devicetree/bindings/i2c/i2c-cbus-gpio.txt
new file mode 100644
index 00000000000..8ce9cd2855b
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-cbus-gpio.txt
@@ -0,0 +1,27 @@
+Device tree bindings for i2c-cbus-gpio driver
+
+Required properties:
+        - compatible = "i2c-cbus-gpio";
+        - gpios: clk, dat, sel
+        - #address-cells = <1>;
+        - #size-cells = <0>;
+
+Optional properties:
+        - child nodes conforming to i2c bus binding
+
+Example:
+
+i2c@0 {
+        compatible = "i2c-cbus-gpio";
+        gpios = <&gpio 66 0 /* clk */
+                 &gpio 65 0 /* dat */
+                 &gpio 64 0 /* sel */
+                >;
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        retu-mfd: retu@1 {
+                compatible = "retu-mfd";
+                reg = <0x1>;
+        };
+};
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt
new file mode 100644
index 00000000000..66709a82554
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt
@@ -0,0 +1,81 @@
+GPIO-based I2C Bus Mux
+
+This binding describes an I2C bus multiplexer that uses GPIOs to
+route the I2C signals.
+
+                                  +-----+  +-----+
+                                  | dev |  | dev |
+    +------------+                +-----+  +-----+
+    | SoC        |                   |        |
+    |            |          /--------+--------+
+    |   +------+ |  +------+    child bus A, on GPIO value set to 0
+    |   | I2C  |-|--| Mux  |
+    |   +------+ |  +--+---+    child bus B, on GPIO value set to 1
+    |            |     |    \----------+--------+--------+
+    |   +------+ |     |               |        |        |
+    |   | GPIO |-|-----+            +-----+  +-----+  +-----+
+    |   +------+ |                  | dev |  | dev |  | dev |
+    +------------+                  +-----+  +-----+  +-----+
+
+Required properties:
+- compatible: i2c-mux-gpio
+- i2c-parent: The phandle of the I2C bus that this multiplexer's master-side
+  port is connected to.
+- mux-gpios: list of gpios used to control the muxer
+* Standard I2C mux properties. See mux.txt in this directory.
+* I2C child bus nodes. See mux.txt in this directory.
+
+Optional properties:
+- idle-state: value to set the muxer to when idle. When no value is
+  given, it defaults to the last value used.
+
+For each i2c child node, an I2C child bus will be created. They will
+be numbered based on their order in the device tree.
+
+Whenever an access is made to a device on a child bus, the value set
+in the revelant node's reg property will be output using the list of
+GPIOs, the first in the list holding the least-significant value.
+
+If an idle state is defined, using the idle-state (optional) property,
+whenever an access is not being made to a device on a child bus, the
+GPIOs will be set according to the idle value.
+
+If an idle state is not defined, the most recently used value will be
+left programmed into hardware whenever no access is being made to a
+device on a child bus.
+
+Example:
+        i2cmux {
+                compatible = "i2c-mux-gpio";
+                #address-cells = <1>;
+                #size-cells = <0>;
+                mux-gpios = <&gpio1 22 0 &gpio1 23 0>;
+                i2c-parent = <&i2c1>;
+
+                i2c@1 {
+                        reg = <1>;
+                        #address-cells = <1>;
+                        #size-cells = <0>;
+
+                        ssd1307: oled@3c {
+                                compatible = "solomon,ssd1307fb-i2c";
+                                reg = <0x3c>;
+                                pwms = <&pwm 4 3000>;
+                                reset-gpios = <&gpio2 7 1>;
+                                reset-active-low;
+                        };
+                };
+
+                i2c@3 {
+                        reg = <3>;
+                        #address-cells = <1>;
+                        #size-cells = <0>;
+
+                        pca9555: pca9555@20 {
+                                compatible = "nxp,pca9555";
+                                gpio-controller;
+                                #gpio-cells = <2>;
+                                reg = <0x20>;
+                        };
+                };
+        };
diff --git a/Documentation/devicetree/bindings/i2c/i2c-ocores.txt b/Documentation/devicetree/bindings/i2c/i2c-ocores.txt
index c15781f4dc8..1637c298a1b 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-ocores.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-ocores.txt
@@ -1,7 +1,7 @@
 Device tree configuration for i2c-ocores
 
 Required properties:
-- compatible      : "opencores,i2c-ocores"
+- compatible      : "opencores,i2c-ocores" or "aeroflexgaisler,i2cmst"
 - reg             : bus address start and address range size of device
 - interrupts      : interrupt number
 - clock-frequency : frequency of bus clock in Hz
diff --git a/Documentation/devicetree/bindings/i2c/i2c-s3c2410.txt b/Documentation/devicetree/bindings/i2c/i2c-s3c2410.txt
index b6cb5a12c67..e9611ace879 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-s3c2410.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-s3c2410.txt
@@ -13,11 +13,17 @@ Required properties:
   - interrupts: interrupt number to the cpu.
   - samsung,i2c-sda-delay: Delay (in ns) applied to data line (SDA) edges.
 
+Required for all cases except "samsung,s3c2440-hdmiphy-i2c":
+  - Samsung GPIO variant (deprecated):
+    - gpios: The order of the gpios should be the following: <SDA, SCL>.
+      The gpio specifier depends on the gpio controller. Required in all
+      cases except for "samsung,s3c2440-hdmiphy-i2c" whose input/output
+      lines are permanently wired to the respective clienta
+  - Pinctrl variant (preferred, if available):
+    - pinctrl-0: Pin control group to be used for this controller.
+    - pinctrl-names: Should contain only one value - "default".
+
 Optional properties:
-  - gpios: The order of the gpios should be the following: <SDA, SCL>.
-    The gpio specifier depends on the gpio controller. Required in all
-    cases except for "samsung,s3c2440-hdmiphy-i2c" whose input/output
-    lines are permanently wired to the respective client
   - samsung,i2c-slave-addr: Slave address in multi-master enviroment. If not
     specified, default value is 0.
   - samsung,i2c-max-bus-freq: Desired frequency in Hz of the bus. If not
@@ -31,8 +37,14 @@ Example:
                 interrupts = <345>;
                 samsung,i2c-sda-delay = <100>;
                 samsung,i2c-max-bus-freq = <100000>;
+                /* Samsung GPIO variant begins here */
                 gpios = <&gpd1 2 0 /* SDA */
                          &gpd1 3 0 /* SCL */>;
+                /* Samsung GPIO variant ends here */
+                /* Pinctrl variant begins here */
+                pinctrl-0 = <&i2c3_bus>;
+                pinctrl-names = "default";
+                /* Pinctrl variant ends here */
                 #address-cells = <1>;
                 #size-cells = <0>;
 
diff --git a/arch/arm/boot/dts/imx28-cfa10049.dts b/arch/arm/boot/dts/imx28-cfa10049.dts
index b222614ac9e..bdc80a4453d 100644
--- a/arch/arm/boot/dts/imx28-cfa10049.dts
+++ b/arch/arm/boot/dts/imx28-cfa10049.dts
@@ -92,6 +92,30 @@
                                 status = "okay";
                         };
 
+                        i2cmux {
+                                compatible = "i2c-mux-gpio";
+                                #address-cells = <1>;
+                                #size-cells = <0>;
+                                mux-gpios = <&gpio1 22 0 &gpio1 23 0>;
+                                i2c-parent = <&i2c1>;
+
+                                i2c@0 {
+                                        reg = <0>;
+                                };
+
+                                i2c@1 {
+                                        reg = <1>;
+                                };
+
+                                i2c@2 {
+                                        reg = <2>;
+                                };
+
+                                i2c@3 {
+                                        reg = <3>;
+                                };
+                        };
+
                         usbphy1: usbphy@8007e000 {
                                 status = "okay";
                         };
diff --git a/arch/arm/mach-omap2/board-n8x0.c b/arch/arm/mach-omap2/board-n8x0.c
index a4e167c55c1..0abb30fe399 100644
--- a/arch/arm/mach-omap2/board-n8x0.c
+++ b/arch/arm/mach-omap2/board-n8x0.c
@@ -16,10 +16,12 @@
 #include <linux/gpio.h>
 #include <linux/init.h>
 #include <linux/io.h>
+#include <linux/irq.h>
 #include <linux/stddef.h>
 #include <linux/i2c.h>
 #include <linux/spi/spi.h>
 #include <linux/usb/musb.h>
+#include <linux/platform_data/i2c-cbus-gpio.h>
 #include <linux/platform_data/spi-omap2-mcspi.h>
 #include <linux/platform_data/mtd-onenand-omap2.h>
 #include <linux/mfd/menelaus.h>
@@ -40,6 +42,45 @@
 #define TUSB6010_GPIO_ENABLE    0
 #define TUSB6010_DMACHAN        0x3f
 
+#if defined(CONFIG_I2C_CBUS_GPIO) || defined(CONFIG_I2C_CBUS_GPIO_MODULE)
+static struct i2c_cbus_platform_data n8x0_cbus_data = {
+        .clk_gpio = 66,
+        .dat_gpio = 65,
+        .sel_gpio = 64,
+};
+
+static struct platform_device n8x0_cbus_device = {
+        .name   = "i2c-cbus-gpio",
+        .id     = 3,
+        .dev    = {
+                .platform_data = &n8x0_cbus_data,
+        },
+};
+
+static struct i2c_board_info n8x0_i2c_board_info_3[] __initdata = {
+        {
+                I2C_BOARD_INFO("retu-mfd", 0x01),
+        },
+};
+
+static void __init n8x0_cbus_init(void)
+{
+        const int retu_irq_gpio = 108;
+
+        if (gpio_request_one(retu_irq_gpio, GPIOF_IN, "Retu IRQ"))
+                return;
+        irq_set_irq_type(gpio_to_irq(retu_irq_gpio), IRQ_TYPE_EDGE_RISING);
+        n8x0_i2c_board_info_3[0].irq = gpio_to_irq(retu_irq_gpio);
+        i2c_register_board_info(3, n8x0_i2c_board_info_3,
+                                ARRAY_SIZE(n8x0_i2c_board_info_3));
+        platform_device_register(&n8x0_cbus_device);
+}
+#else /* CONFIG_I2C_CBUS_GPIO */
+static void __init n8x0_cbus_init(void)
+{
+}
+#endif /* CONFIG_I2C_CBUS_GPIO */
+
 #if defined(CONFIG_USB_MUSB_TUSB6010) || defined(CONFIG_USB_MUSB_TUSB6010_MODULE)
 /*
  * Enable or disable power to TUSB6010. When enabling, turn on 3.3 V and
@@ -678,6 +719,7 @@ static void __init n8x0_init_machine(void)
         gpmc_onenand_init(board_onenand_data);
         n8x0_mmc_init();
         n8x0_usb_init();
+        n8x0_cbus_init();
 }
 
 MACHINE_START(NOKIA_N800, "Nokia N800")
diff --git a/arch/arm/mach-omap2/i2c.c b/arch/arm/mach-omap2/i2c.c
index fbb9b152cd5..df6d6acbc9e 100644
--- a/arch/arm/mach-omap2/i2c.c
+++ b/arch/arm/mach-omap2/i2c.c
@@ -120,6 +120,16 @@ static int __init omap_i2c_nr_ports(void)
         return ports;
 }
 
+/*
+ * XXX This function is a temporary compatibility wrapper - only
+ * needed until the I2C driver can be converted to call
+ * omap_pm_set_max_dev_wakeup_lat() and handle a return code.
+ */
+static void omap_pm_set_max_mpu_wakeup_lat_compat(struct device *dev, long t)
+{
+        omap_pm_set_max_mpu_wakeup_lat(dev, t);
+}
+
 static const char name[] = "omap_i2c";
 
 int __init omap_i2c_add_bus(struct omap_i2c_bus_platform_data *i2c_pdata,
@@ -157,6 +167,15 @@ int __init omap_i2c_add_bus(struct omap_i2c_bus_platform_data *i2c_pdata,
         dev_attr = (struct omap_i2c_dev_attr *)oh->dev_attr;
         pdata->flags = dev_attr->flags;
 
+        /*
+         * When waiting for completion of a i2c transfer, we need to
+         * set a wake up latency constraint for the MPU. This is to
+         * ensure quick enough wakeup from idle, when transfer
+         * completes.
+         * Only omap3 has support for constraints
+         */
+        if (cpu_is_omap34xx())
+                pdata->set_mpu_wkup_lat = omap_pm_set_max_mpu_wakeup_lat_compat;
         pdev = omap_device_build(name, bus_id, oh, pdata,
                         sizeof(struct omap_i2c_bus_platform_data),
                         NULL, 0, 0);
diff --git a/arch/arm/mach-omap2/omap_hwmod_2430_data.c b/arch/arm/mach-omap2/omap_hwmod_2430_data.c
index 6c8fa70ddad..d2d3840557c 100644
--- a/arch/arm/mach-omap2/omap_hwmod_2430_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_2430_data.c
@@ -77,8 +77,7 @@ static struct omap_hwmod_class i2c_class = {
 
 static struct omap_i2c_dev_attr i2c_dev_attr = {
         .fifo_depth     = 8, /* bytes */
-        .flags          = OMAP_I2C_FLAG_APPLY_ERRATA_I207 |
-                          OMAP_I2C_FLAG_BUS_SHIFT_2 |
+        .flags          = OMAP_I2C_FLAG_BUS_SHIFT_2 |
                           OMAP_I2C_FLAG_FORCE_19200_INT_CLK,
 };
 
diff --git a/arch/arm/mach-omap2/omap_hwmod_33xx_data.c b/arch/arm/mach-omap2/omap_hwmod_33xx_data.c
index 32820d89f5b..081c71edddf 100644
--- a/arch/arm/mach-omap2/omap_hwmod_33xx_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_33xx_data.c
@@ -1118,8 +1118,7 @@ static struct omap_hwmod_class i2c_class = {
 };
 
 static struct omap_i2c_dev_attr i2c_dev_attr = {
-        .flags = OMAP_I2C_FLAG_BUS_SHIFT_NONE |
-                  OMAP_I2C_FLAG_RESET_REGS_POSTIDLE,
+        .flags = OMAP_I2C_FLAG_BUS_SHIFT_NONE,
 };
 
 /* i2c1 */
diff --git a/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c b/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
index ec4499e5a4c..8bb2628df34 100644
--- a/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
@@ -794,9 +794,7 @@ static struct omap_hwmod omap3xxx_dss_venc_hwmod = {
 /* I2C1 */
 static struct omap_i2c_dev_attr i2c1_dev_attr = {
         .fifo_depth     = 8, /* bytes */
-        .flags          = OMAP_I2C_FLAG_APPLY_ERRATA_I207 |
-                          OMAP_I2C_FLAG_RESET_REGS_POSTIDLE |
-                          OMAP_I2C_FLAG_BUS_SHIFT_2,
+        .flags          = OMAP_I2C_FLAG_BUS_SHIFT_2,
 };
 
 static struct omap_hwmod omap3xxx_i2c1_hwmod = {
@@ -821,9 +819,7 @@ static struct omap_hwmod omap3xxx_i2c1_hwmod = {
 /* I2C2 */
 static struct omap_i2c_dev_attr i2c2_dev_attr = {
         .fifo_depth     = 8, /* bytes */
-        .flags = OMAP_I2C_FLAG_APPLY_ERRATA_I207 |
-                 OMAP_I2C_FLAG_RESET_REGS_POSTIDLE |
-                 OMAP_I2C_FLAG_BUS_SHIFT_2,
+        .flags = OMAP_I2C_FLAG_BUS_SHIFT_2,
 };
 
 static struct omap_hwmod omap3xxx_i2c2_hwmod = {
@@ -848,9 +844,7 @@ static struct omap_hwmod omap3xxx_i2c2_hwmod = {
 /* I2C3 */
 static struct omap_i2c_dev_attr i2c3_dev_attr = {
         .fifo_depth     = 64, /* bytes */
-        .flags = OMAP_I2C_FLAG_APPLY_ERRATA_I207 |
-                 OMAP_I2C_FLAG_RESET_REGS_POSTIDLE |
-                 OMAP_I2C_FLAG_BUS_SHIFT_2,
+        .flags = OMAP_I2C_FLAG_BUS_SHIFT_2,
 };
 
 static struct omap_hwmod_irq_info i2c3_mpu_irqs[] = {
diff --git a/arch/arm/mach-omap2/omap_hwmod_44xx_data.c b/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
index eb61cfd9452..272b0178dba 100644
--- a/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_44xx_data.c
@@ -1529,8 +1529,7 @@ static struct omap_hwmod_class omap44xx_i2c_hwmod_class = {
 };
 
 static struct omap_i2c_dev_attr i2c_dev_attr = {
-        .flags  = OMAP_I2C_FLAG_BUS_SHIFT_NONE |
-                        OMAP_I2C_FLAG_RESET_REGS_POSTIDLE,
+        .flags  = OMAP_I2C_FLAG_BUS_SHIFT_NONE,
 };
 
 /* i2c1 */
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index c7bff51fe52..bdca5111eb9 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -337,6 +337,16 @@ config I2C_BLACKFIN_TWI_CLK_KHZ
         help
           The unit of the TWI clock is kHz.
 
+config I2C_CBUS_GPIO
+        tristate "CBUS I2C driver"
+        depends on GENERIC_GPIO
+        help
+          Support for CBUS access using I2C API. Mostly relevant for Nokia
+          Internet Tablets (770, N800 and N810).
+
+          This driver can also be built as a module.  If so, the module
+          will be called i2c-cbus-gpio.
+
 config I2C_CPM
         tristate "Freescale CPM1 or CPM2 (MPC8xx/826x)"
         depends on (CPM1 || CPM2) && OF_I2C
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index e5cb209d276..6181f3ff263 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -31,6 +31,7 @@ obj-$(CONFIG_I2C_POWERMAC)	+= i2c-powermac.o
 obj-$(CONFIG_I2C_AT91)          += i2c-at91.o
 obj-$(CONFIG_I2C_AU1550)        += i2c-au1550.o
 obj-$(CONFIG_I2C_BLACKFIN_TWI)  += i2c-bfin-twi.o
+obj-$(CONFIG_I2C_CBUS_GPIO)     += i2c-cbus-gpio.o
 obj-$(CONFIG_I2C_CPM)           += i2c-cpm.o
 obj-$(CONFIG_I2C_DAVINCI)       += i2c-davinci.o
 obj-$(CONFIG_I2C_DESIGNWARE_CORE)       += i2c-designware-core.o
diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
index c02bf208084..b4575ee4bdf 100644
--- a/drivers/i2c/busses/i2c-at91.c
+++ b/drivers/i2c/busses/i2c-at91.c
@@ -19,6 +19,8 @@
 
 #include <linux/clk.h>
 #include <linux/completion.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
 #include <linux/err.h>
 #include <linux/i2c.h>
 #include <linux/interrupt.h>
@@ -29,9 +31,11 @@
 #include <linux/of_i2c.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
+#include <linux/platform_data/dma-atmel.h>
 
 #define TWI_CLK_HZ              100000                  /* max 400 Kbits/s */
 #define AT91_I2C_TIMEOUT        msecs_to_jiffies(100)   /* transfer timeout */
+#define AT91_I2C_DMA_THRESHOLD  8                       /* enable DMA if transfer size is bigger than this threshold */
 
 /* AT91 TWI register definitions */
 #define AT91_TWI_CR             0x0000  /* Control Register */
@@ -66,24 +70,39 @@
 #define AT91_TWI_THR            0x0034  /* Transmit Holding Register */
 
 struct at91_twi_pdata {
-        unsigned        clk_max_div;
-        unsigned        clk_offset;
-        bool            has_unre_flag;
+        unsigned clk_max_div;
+        unsigned clk_offset;
+        bool has_unre_flag;
+        bool has_dma_support;
+        struct at_dma_slave dma_slave;
+};
+
+struct at91_twi_dma {
+        struct dma_chan *chan_rx;
+        struct dma_chan *chan_tx;
+        struct scatterlist sg;
+        struct dma_async_tx_descriptor *data_desc;
+        enum dma_data_direction direction;
+        bool buf_mapped;
+        bool xfer_in_progress;
 };
 
 struct at91_twi_dev {
-        struct device           *dev;
-        void __iomem            *base;
-        struct completion       cmd_complete;
-        struct clk              *clk;
-        u8                      *buf;
-        size_t                  buf_len;
-        struct i2c_msg          *msg;
-        int                     irq;
-        unsigned                transfer_status;
-        struct i2c_adapter      adapter;
-        unsigned                twi_cwgr_reg;
-        struct at91_twi_pdata   *pdata;
+        struct device *dev;
+        void __iomem *base;
+        struct completion cmd_complete;
+        struct clk *clk;
+        u8 *buf;
+        size_t buf_len;
+        struct i2c_msg *msg;
+        int irq;
+        unsigned imr;
+        unsigned transfer_status;
+        struct i2c_adapter adapter;
+        unsigned twi_cwgr_reg;
+        struct at91_twi_pdata *pdata;
+        bool use_dma;
+        struct at91_twi_dma dma;
 };
 
 static unsigned at91_twi_read(struct at91_twi_dev *dev, unsigned reg)
@@ -102,6 +121,17 @@ static void at91_disable_twi_interrupts(struct at91_twi_dev *dev)
                        AT91_TWI_TXCOMP | AT91_TWI_RXRDY | AT91_TWI_TXRDY);
 }
 
+static void at91_twi_irq_save(struct at91_twi_dev *dev)
+{
+        dev->imr = at91_twi_read(dev, AT91_TWI_IMR) & 0x7;
+        at91_disable_twi_interrupts(dev);
+}
+
+static void at91_twi_irq_restore(struct at91_twi_dev *dev)
+{
+        at91_twi_write(dev, AT91_TWI_IER, dev->imr);
+}
+
 static void at91_init_twi_bus(struct at91_twi_dev *dev)
 {
         at91_disable_twi_interrupts(dev);
@@ -138,6 +168,28 @@ static void __devinit at91_calc_twi_clock(struct at91_twi_dev *dev, int twi_clk)
         dev_dbg(dev->dev, "cdiv %d ckdiv %d\n", cdiv, ckdiv);
 }
 
+static void at91_twi_dma_cleanup(struct at91_twi_dev *dev)
+{
+        struct at91_twi_dma *dma = &dev->dma;
+
+        at91_twi_irq_save(dev);
+
+        if (dma->xfer_in_progress) {
+                if (dma->direction == DMA_FROM_DEVICE)
+                        dmaengine_terminate_all(dma->chan_rx);
+                else
+                        dmaengine_terminate_all(dma->chan_tx);
+                dma->xfer_in_progress = false;
+        }
+        if (dma->buf_mapped) {
+                dma_unmap_single(dev->dev, sg_dma_address(&dma->sg),
+                                 dev->buf_len, dma->direction);
+                dma->buf_mapped = false;
+        }
+
+        at91_twi_irq_restore(dev);
+}
+
 static void at91_twi_write_next_byte(struct at91_twi_dev *dev)
 {
         if (dev->buf_len <= 0)
@@ -154,6 +206,60 @@ static void at91_twi_write_next_byte(struct at91_twi_dev *dev)
         ++dev->buf;
 }
 
+static void at91_twi_write_data_dma_callback(void *data)
+{
+        struct at91_twi_dev *dev = (struct at91_twi_dev *)data;
+
+        dma_unmap_single(dev->dev, sg_dma_address(&dev->dma.sg),
+                         dev->buf_len, DMA_MEM_TO_DEV);
+
+        at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_STOP);
+}
+
+static void at91_twi_write_data_dma(struct at91_twi_dev *dev)
+{
+        dma_addr_t dma_addr;
+        struct dma_async_tx_descriptor *txdesc;
+        struct at91_twi_dma *dma = &dev->dma;
+        struct dma_chan *chan_tx = dma->chan_tx;
+
+        if (dev->buf_len <= 0)
+                return;
+
+        dma->direction = DMA_TO_DEVICE;
+
+        at91_twi_irq_save(dev);
+        dma_addr = dma_map_single(dev->dev, dev->buf, dev->buf_len,
+                                  DMA_TO_DEVICE);
+        if (dma_mapping_error(dev->dev, dma_addr)) {
+                dev_err(dev->dev, "dma map failed\n");
+                return;
+        }
+        dma->buf_mapped = true;
+        at91_twi_irq_restore(dev);
+        sg_dma_len(&dma->sg) = dev->buf_len;
+        sg_dma_address(&dma->sg) = dma_addr;
+
+        txdesc = dmaengine_prep_slave_sg(chan_tx, &dma->sg, 1, DMA_MEM_TO_DEV,
+                                         DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+        if (!txdesc) {
+                dev_err(dev->dev, "dma prep slave sg failed\n");
+                goto error;
+        }
+
+        txdesc->callback = at91_twi_write_data_dma_callback;
+        txdesc->callback_param = dev;
+
+        dma->xfer_in_progress = true;
+        dmaengine_submit(txdesc);
+        dma_async_issue_pending(chan_tx);
+
+        return;
+
+error:
+        at91_twi_dma_cleanup(dev);
+}
+
 static void at91_twi_read_next_byte(struct at91_twi_dev *dev)
 {
         if (dev->buf_len <= 0)
@@ -179,6 +285,61 @@ static void at91_twi_read_next_byte(struct at91_twi_dev *dev)
         ++dev->buf;
 }
 
+static void at91_twi_read_data_dma_callback(void *data)
+{
+        struct at91_twi_dev *dev = (struct at91_twi_dev *)data;
+
+        dma_unmap_single(dev->dev, sg_dma_address(&dev->dma.sg),
+                         dev->buf_len, DMA_DEV_TO_MEM);
+
+        /* The last two bytes have to be read without using dma */
+        dev->buf += dev->buf_len - 2;
+        dev->buf_len = 2;
+        at91_twi_write(dev, AT91_TWI_IER, AT91_TWI_RXRDY);
+}
+
+static void at91_twi_read_data_dma(struct at91_twi_dev *dev)
+{
+        dma_addr_t dma_addr;
+        struct dma_async_tx_descriptor *rxdesc;
+        struct at91_twi_dma *dma = &dev->dma;
+        struct dma_chan *chan_rx = dma->chan_rx;
+
+        dma->direction = DMA_FROM_DEVICE;
+
+        /* Keep in mind that we won't use dma to read the last two bytes */
+        at91_twi_irq_save(dev);
+        dma_addr = dma_map_single(dev->dev, dev->buf, dev->buf_len - 2,
+                                  DMA_FROM_DEVICE);
+        if (dma_mapping_error(dev->dev, dma_addr)) {
+                dev_err(dev->dev, "dma map failed\n");
+                return;
+        }
+        dma->buf_mapped = true;
+        at91_twi_irq_restore(dev);
+        dma->sg.dma_address = dma_addr;
+        sg_dma_len(&dma->sg) = dev->buf_len - 2;
+
+        rxdesc = dmaengine_prep_slave_sg(chan_rx, &dma->sg, 1, DMA_DEV_TO_MEM,
+                                         DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+        if (!rxdesc) {
+                dev_err(dev->dev, "dma prep slave sg failed\n");
+                goto error;
+        }
+
+        rxdesc->callback = at91_twi_read_data_dma_callback;
+        rxdesc->callback_param = dev;
+
+        dma->xfer_in_progress = true;
+        dmaengine_submit(rxdesc);
+        dma_async_issue_pending(dma->chan_rx);
+
+        return;
+
+error:
+        at91_twi_dma_cleanup(dev);
+}
+
 static irqreturn_t atmel_twi_interrupt(int irq, void *dev_id)
 {
         struct at91_twi_dev *dev = dev_id;
@@ -229,12 +390,36 @@ static int at91_do_twi_transfer(struct at91_twi_dev *dev)
                 if (dev->buf_len <= 1 && !(dev->msg->flags & I2C_M_RECV_LEN))
                         start_flags |= AT91_TWI_STOP;
                 at91_twi_write(dev, AT91_TWI_CR, start_flags);
-                at91_twi_write(dev, AT91_TWI_IER,
+                /*
+                 * When using dma, the last byte has to be read manually in
+                 * order to not send the stop command too late and then
+                 * to receive extra data. In practice, there are some issues
+                 * if you use the dma to read n-1 bytes because of latency.
+                 * Reading n-2 bytes with dma and the two last ones manually
+                 * seems to be the best solution.
+                 */
+                if (dev->use_dma && (dev->buf_len > AT91_I2C_DMA_THRESHOLD)) {
+                        at91_twi_read_data_dma(dev);
+                        /*
+                         * It is important to enable TXCOMP irq here because
+                         * doing it only when transferring the last two bytes
+                         * will mask NACK errors since TXCOMP is set when a
+                         * NACK occurs.
+                         */
+                        at91_twi_write(dev, AT91_TWI_IER,
+                               AT91_TWI_TXCOMP);
+                } else
+                        at91_twi_write(dev, AT91_TWI_IER,
                                AT91_TWI_TXCOMP | AT91_TWI_RXRDY);
         } else {
-                at91_twi_write_next_byte(dev);
-                at91_twi_write(dev, AT91_TWI_IER,
-                               AT91_TWI_TXCOMP | AT91_TWI_TXRDY);
+                if (dev->use_dma && (dev->buf_len > AT91_I2C_DMA_THRESHOLD)) {
+                        at91_twi_write_data_dma(dev);
+                        at91_twi_write(dev, AT91_TWI_IER, AT91_TWI_TXCOMP);
+                } else {
+                        at91_twi_write_next_byte(dev);
+                        at91_twi_write(dev, AT91_TWI_IER,
+                                AT91_TWI_TXCOMP | AT91_TWI_TXRDY);
+                }
         }
 
         ret = wait_for_completion_interruptible_timeout(&dev->cmd_complete,
@@ -242,23 +427,31 @@ static int at91_do_twi_transfer(struct at91_twi_dev *dev)
         if (ret == 0) {
                 dev_err(dev->dev, "controller timed out\n");
                 at91_init_twi_bus(dev);
-                return -ETIMEDOUT;
+                ret = -ETIMEDOUT;
+                goto error;
         }
         if (dev->transfer_status & AT91_TWI_NACK) {
                 dev_dbg(dev->dev, "received nack\n");
-                return -EREMOTEIO;
+                ret = -EREMOTEIO;
+                goto error;
         }
         if (dev->transfer_status & AT91_TWI_OVRE) {
                 dev_err(dev->dev, "overrun while reading\n");
-                return -EIO;
+                ret = -EIO;
+                goto error;
         }
         if (has_unre_flag && dev->transfer_status & AT91_TWI_UNRE) {
                 dev_err(dev->dev, "underrun while writing\n");
-                return -EIO;
+                ret = -EIO;
+                goto error;
         }
         dev_dbg(dev->dev, "transfer complete\n");
 
         return 0;
+
+error:
+        at91_twi_dma_cleanup(dev);
+        return ret;
 }
 
 static int at91_twi_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, int num)
@@ -329,36 +522,42 @@ static struct at91_twi_pdata at91rm9200_config = {
         .clk_max_div = 5,
         .clk_offset = 3,
         .has_unre_flag = true,
+        .has_dma_support = false,
 };
 
 static struct at91_twi_pdata at91sam9261_config = {
         .clk_max_div = 5,
         .clk_offset = 4,
         .has_unre_flag = false,
+        .has_dma_support = false,
 };
 
 static struct at91_twi_pdata at91sam9260_config = {
         .clk_max_div = 7,
         .clk_offset = 4,
         .has_unre_flag = false,
+        .has_dma_support = false,
 };
 
 static struct at91_twi_pdata at91sam9g20_config = {
         .clk_max_div = 7,
         .clk_offset = 4,
         .has_unre_flag = false,
+        .has_dma_support = false,
 };
 
 static struct at91_twi_pdata at91sam9g10_config = {
         .clk_max_div = 7,
         .clk_offset = 4,
         .has_unre_flag = false,
+        .has_dma_support = false,
 };
 
 static struct at91_twi_pdata at91sam9x5_config = {
         .clk_max_div = 7,
         .clk_offset = 4,
         .has_unre_flag = false,
+        .has_dma_support = true,
 };
 
 static const struct platform_device_id at91_twi_devtypes[] = {
@@ -405,6 +604,90 @@ MODULE_DEVICE_TABLE(of, atmel_twi_dt_ids);
 #define atmel_twi_dt_ids NULL
 #endif
 
+static bool __devinit filter(struct dma_chan *chan, void *slave)
+{
+        struct at_dma_slave *sl = slave;
+
+        if (sl->dma_dev == chan->device->dev) {
+                chan->private = sl;
+                return true;
+        } else {
+                return false;
+        }
+}
+
+static int __devinit at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr)
+{
+        int ret = 0;
+        struct at_dma_slave *sdata;
+        struct dma_slave_config slave_config;
+        struct at91_twi_dma *dma = &dev->dma;
+
+        sdata = &dev->pdata->dma_slave;
+
+        memset(&slave_config, 0, sizeof(slave_config));
+        slave_config.src_addr = (dma_addr_t)phy_addr + AT91_TWI_RHR;
+        slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+        slave_config.src_maxburst = 1;
+        slave_config.dst_addr = (dma_addr_t)phy_addr + AT91_TWI_THR;
+        slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+        slave_config.dst_maxburst = 1;
+        slave_config.device_fc = false;
+
+        if (sdata && sdata->dma_dev) {
+                dma_cap_mask_t mask;
+
+                dma_cap_zero(mask);
+                dma_cap_set(DMA_SLAVE, mask);
+                dma->chan_tx = dma_request_channel(mask, filter, sdata);
+                if (!dma->chan_tx) {
+                        dev_err(dev->dev, "no DMA channel available for tx\n");
+                        ret = -EBUSY;
+                        goto error;
+                }
+                dma->chan_rx = dma_request_channel(mask, filter, sdata);
+                if (!dma->chan_rx) {
+                        dev_err(dev->dev, "no DMA channel available for rx\n");
+                        ret = -EBUSY;
+                        goto error;
+                }
+        } else {
+                ret = -EINVAL;
+                goto error;
+        }
+
+        slave_config.direction = DMA_MEM_TO_DEV;
+        if (dmaengine_slave_config(dma->chan_tx, &slave_config)) {
+                dev_err(dev->dev, "failed to configure tx channel\n");
+                ret = -EINVAL;
+                goto error;
+        }
+
+        slave_config.direction = DMA_DEV_TO_MEM;
+        if (dmaengine_slave_config(dma->chan_rx, &slave_config)) {
+                dev_err(dev->dev, "failed to configure rx channel\n");
+                ret = -EINVAL;
+                goto error;
+        }
+
+        sg_init_table(&dma->sg, 1);
+        dma->buf_mapped = false;
+        dma->xfer_in_progress = false;
+
+        dev_info(dev->dev, "using %s (tx) and %s (rx) for DMA transfers\n",
+                 dma_chan_name(dma->chan_tx), dma_chan_name(dma->chan_rx));
+
+        return ret;
+
+error:
+        dev_info(dev->dev, "can't use DMA\n");
+        if (dma->chan_rx)
+                dma_release_channel(dma->chan_rx);
+        if (dma->chan_tx)
+                dma_release_channel(dma->chan_tx);
+        return ret;
+}
+
 static struct at91_twi_pdata * __devinit at91_twi_get_driver_data(
                                         struct platform_device *pdev)
 {
@@ -413,7 +696,7 @@ static struct at91_twi_pdata * __devinit at91_twi_get_driver_data(
                 match = of_match_node(atmel_twi_dt_ids, pdev->dev.of_node);
                 if (!match)
                         return NULL;
-                return match->data;
+                return (struct at91_twi_pdata *)match->data;
         }
         return (struct at91_twi_pdata *) platform_get_device_id(pdev)->driver_data;
 }
@@ -423,6 +706,7 @@ static int __devinit at91_twi_probe(struct platform_device *pdev)
         struct at91_twi_dev *dev;
         struct resource *mem;
         int rc;
+        u32 phy_addr;
 
         dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
         if (!dev)
@@ -433,6 +717,7 @@ static int __devinit at91_twi_probe(struct platform_device *pdev)
         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
         if (!mem)
                 return -ENODEV;
+        phy_addr = mem->start;
 
         dev->pdata = at91_twi_get_driver_data(pdev);
         if (!dev->pdata)
@@ -462,6 +747,11 @@ static int __devinit at91_twi_probe(struct platform_device *pdev)
         }
         clk_prepare_enable(dev->clk);
 
+        if (dev->pdata->has_dma_support) {
+                if (at91_twi_configure_dma(dev, phy_addr) == 0)
+                        dev->use_dma = true;
+        }
+
         at91_calc_twi_clock(dev, TWI_CLK_HZ);
         at91_init_twi_bus(dev);
 
diff --git a/drivers/i2c/busses/i2c-cbus-gpio.c b/drivers/i2c/busses/i2c-cbus-gpio.c
new file mode 100644
index 00000000000..98386d65931
--- /dev/null
+++ b/drivers/i2c/busses/i2c-cbus-gpio.c
@@ -0,0 +1,300 @@
+/*
+ * CBUS I2C driver for Nokia Internet Tablets.
+ *
+ * Copyright (C) 2004-2010 Nokia Corporation
+ *
+ * Based on code written by Juha Yrjölä, David Weinehall, Mikko Ylinen and
+ * Felipe Balbi. Converted to I2C driver by Aaro Koskinen.
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/io.h>
+#include <linux/i2c.h>
+#include <linux/gpio.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_gpio.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/platform_data/i2c-cbus-gpio.h>
+
+/*
+ * Bit counts are derived from Nokia implementation. These should be checked
+ * if other CBUS implementations appear.
+ */
+#define CBUS_ADDR_BITS  3
+#define CBUS_REG_BITS   5
+
+struct cbus_host {
+        spinlock_t      lock;           /* host lock */
+        struct device   *dev;
+        int             clk_gpio;
+        int             dat_gpio;
+        int             sel_gpio;
+};
+
+/**
+ * cbus_send_bit - sends one bit over the bus
+ * @host: the host we're using
+ * @bit: one bit of information to send
+ */
+static void cbus_send_bit(struct cbus_host *host, unsigned bit)
+{
+        gpio_set_value(host->dat_gpio, bit ? 1 : 0);
+        gpio_set_value(host->clk_gpio, 1);
+        gpio_set_value(host->clk_gpio, 0);
+}
+
+/**
+ * cbus_send_data - sends @len amount of data over the bus
+ * @host: the host we're using
+ * @data: the data to send
+ * @len: size of the transfer
+ */
+static void cbus_send_data(struct cbus_host *host, unsigned data, unsigned len)
+{
+        int i;
+
+        for (i = len; i > 0; i--)
+                cbus_send_bit(host, data & (1 << (i - 1)));
+}
+
+/**
+ * cbus_receive_bit - receives one bit from the bus
+ * @host: the host we're using
+ */
+static int cbus_receive_bit(struct cbus_host *host)
+{
+        int ret;
+
+        gpio_set_value(host->clk_gpio, 1);
+        ret = gpio_get_value(host->dat_gpio);
+        gpio_set_value(host->clk_gpio, 0);
+        return ret;
+}
+
+/**
+ * cbus_receive_word - receives 16-bit word from the bus
+ * @host: the host we're using
+ */
+static int cbus_receive_word(struct cbus_host *host)
+{
+        int ret = 0;
+        int i;
+
+        for (i = 16; i > 0; i--) {
+                int bit = cbus_receive_bit(host);
+
+                if (bit < 0)
+                        return bit;
+
+                if (bit)
+                        ret |= 1 << (i - 1);
+        }
+        return ret;
+}
+
+/**
+ * cbus_transfer - transfers data over the bus
+ * @host: the host we're using
+ * @rw: read/write flag
+ * @dev: device address
+ * @reg: register address
+ * @data: if @rw == I2C_SBUS_WRITE data to send otherwise 0
+ */
+static int cbus_transfer(struct cbus_host *host, char rw, unsigned dev,
+                         unsigned reg, unsigned data)
+{
+        unsigned long flags;
+        int ret;
+
+        /* We don't want interrupts disturbing our transfer */
+        spin_lock_irqsave(&host->lock, flags);
+
+        /* Reset state and start of transfer, SEL stays down during transfer */
+        gpio_set_value(host->sel_gpio, 0);
+
+        /* Set the DAT pin to output */
+        gpio_direction_output(host->dat_gpio, 1);
+
+        /* Send the device address */
+        cbus_send_data(host, dev, CBUS_ADDR_BITS);
+
+        /* Send the rw flag */
+        cbus_send_bit(host, rw == I2C_SMBUS_READ);
+
+        /* Send the register address */
+        cbus_send_data(host, reg, CBUS_REG_BITS);
+
+        if (rw == I2C_SMBUS_WRITE) {
+                cbus_send_data(host, data, 16);
+                ret = 0;
+        } else {
+                ret = gpio_direction_input(host->dat_gpio);
+                if (ret) {
+                        dev_dbg(host->dev, "failed setting direction\n");
+                        goto out;
+                }
+                gpio_set_value(host->clk_gpio, 1);
+
+                ret = cbus_receive_word(host);
+                if (ret < 0) {
+                        dev_dbg(host->dev, "failed receiving data\n");
+                        goto out;
+                }
+        }
+
+        /* Indicate end of transfer, SEL goes up until next transfer */
+        gpio_set_value(host->sel_gpio, 1);
+        gpio_set_value(host->clk_gpio, 1);
+        gpio_set_value(host->clk_gpio, 0);
+
+out:
+        spin_unlock_irqrestore(&host->lock, flags);
+
+        return ret;
+}
+
+static int cbus_i2c_smbus_xfer(struct i2c_adapter       *adapter,
+                               u16                      addr,
+                               unsigned short           flags,
+                               char                     read_write,
+                               u8                       command,
+                               int                      size,
+                               union i2c_smbus_data     *data)
+{
+        struct cbus_host *chost = i2c_get_adapdata(adapter);
+        int ret;
+
+        if (size != I2C_SMBUS_WORD_DATA)
+                return -EINVAL;
+
+        ret = cbus_transfer(chost, read_write == I2C_SMBUS_READ, addr,
+                            command, data->word);
+        if (ret < 0)
+                return ret;
+
+        if (read_write == I2C_SMBUS_READ)
+                data->word = ret;
+
+        return 0;
+}
+
+static u32 cbus_i2c_func(struct i2c_adapter *adapter)
+{
+        return I2C_FUNC_SMBUS_READ_WORD_DATA | I2C_FUNC_SMBUS_WRITE_WORD_DATA;
+}
+
+static const struct i2c_algorithm cbus_i2c_algo = {
+        .smbus_xfer     = cbus_i2c_smbus_xfer,
+        .functionality  = cbus_i2c_func,
+};
+
+static int cbus_i2c_remove(struct platform_device *pdev)
+{
+        struct i2c_adapter *adapter = platform_get_drvdata(pdev);
+
+        return i2c_del_adapter(adapter);
+}
+
+static int cbus_i2c_probe(struct platform_device *pdev)
+{
+        struct i2c_adapter *adapter;
+        struct cbus_host *chost;
+        int ret;
+
+        adapter = devm_kzalloc(&pdev->dev, sizeof(struct i2c_adapter),
+                               GFP_KERNEL);
+        if (!adapter)
+                return -ENOMEM;
+
+        chost = devm_kzalloc(&pdev->dev, sizeof(*chost), GFP_KERNEL);
+        if (!chost)
+                return -ENOMEM;
+
+        if (pdev->dev.of_node) {
+                struct device_node *dnode = pdev->dev.of_node;
+                if (of_gpio_count(dnode) != 3)
+                        return -ENODEV;
+                chost->clk_gpio = of_get_gpio(dnode, 0);
+                chost->dat_gpio = of_get_gpio(dnode, 1);
+                chost->sel_gpio = of_get_gpio(dnode, 2);
+        } else if (pdev->dev.platform_data) {
+                struct i2c_cbus_platform_data *pdata = pdev->dev.platform_data;
+                chost->clk_gpio = pdata->clk_gpio;
+                chost->dat_gpio = pdata->dat_gpio;
+                chost->sel_gpio = pdata->sel_gpio;
+        } else {
+                return -ENODEV;
+        }
+
+        adapter->owner          = THIS_MODULE;
+        adapter->class          = I2C_CLASS_HWMON;
+        adapter->dev.parent     = &pdev->dev;
+        adapter->nr             = pdev->id;
+        adapter->timeout        = HZ;
+        adapter->algo           = &cbus_i2c_algo;
+        strlcpy(adapter->name, "CBUS I2C adapter", sizeof(adapter->name));
+
+        spin_lock_init(&chost->lock);
+        chost->dev = &pdev->dev;
+
+        ret = devm_gpio_request_one(&pdev->dev, chost->clk_gpio,
+                                    GPIOF_OUT_INIT_LOW, "CBUS clk");
+        if (ret)
+                return ret;
+
+        ret = devm_gpio_request_one(&pdev->dev, chost->dat_gpio, GPIOF_IN,
+                                    "CBUS data");
+        if (ret)
+                return ret;
+
+        ret = devm_gpio_request_one(&pdev->dev, chost->sel_gpio,
+                                    GPIOF_OUT_INIT_HIGH, "CBUS sel");
+        if (ret)
+                return ret;
+
+        i2c_set_adapdata(adapter, chost);
+        platform_set_drvdata(pdev, adapter);
+
+        return i2c_add_numbered_adapter(adapter);
+}
+
+#if defined(CONFIG_OF)
+static const struct of_device_id i2c_cbus_dt_ids[] = {
+        { .compatible = "i2c-cbus-gpio", },
+        { }
+};
+MODULE_DEVICE_TABLE(of, i2c_cbus_dt_ids);
+#endif
+
+static struct platform_driver cbus_i2c_driver = {
+        .probe  = cbus_i2c_probe,
+        .remove = cbus_i2c_remove,
+        .driver = {
+                .owner  = THIS_MODULE,
+                .name   = "i2c-cbus-gpio",
+        },
+};
+module_platform_driver(cbus_i2c_driver);
+
+MODULE_ALIAS("platform:i2c-cbus-gpio");
+MODULE_DESCRIPTION("CBUS I2C driver");
+MODULE_AUTHOR("Juha Yrjölä");
+MODULE_AUTHOR("David Weinehall");
+MODULE_AUTHOR("Mikko Ylinen");
+MODULE_AUTHOR("Felipe Balbi");
+MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/i2c/busses/i2c-gpio.c b/drivers/i2c/busses/i2c-gpio.c
index e62d2d93862..257299a92df 100644
--- a/drivers/i2c/busses/i2c-gpio.c
+++ b/drivers/i2c/busses/i2c-gpio.c
@@ -184,7 +184,11 @@ static int __devinit i2c_gpio_probe(struct platform_device *pdev)
         bit_data->data = pdata;
 
         adap->owner = THIS_MODULE;
-        snprintf(adap->name, sizeof(adap->name), "i2c-gpio%d", pdev->id);
+        if (pdev->dev.of_node)
+                strlcpy(adap->name, dev_name(&pdev->dev), sizeof(adap->name));
+        else
+                snprintf(adap->name, sizeof(adap->name), "i2c-gpio%d", pdev->id);
+
         adap->algo_data = bit_data;
         adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
         adap->dev.parent = &pdev->dev;
diff --git a/drivers/i2c/busses/i2c-mxs.c b/drivers/i2c/busses/i2c-mxs.c
index 0670da79ee5..6ed53da9e1f 100644
--- a/drivers/i2c/busses/i2c-mxs.c
+++ b/drivers/i2c/busses/i2c-mxs.c
@@ -359,7 +359,7 @@ static int mxs_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
 
 static u32 mxs_i2c_func(struct i2c_adapter *adap)
 {
-        return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
+        return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
 }
 
 static irqreturn_t mxs_i2c_isr(int this_irq, void *dev_id)
diff --git a/drivers/i2c/busses/i2c-nomadik.c b/drivers/i2c/busses/i2c-nomadik.c
index 02c3115a2df..8b2ffcf4532 100644
--- a/drivers/i2c/busses/i2c-nomadik.c
+++ b/drivers/i2c/busses/i2c-nomadik.c
@@ -435,13 +435,6 @@ static int read_i2c(struct nmk_i2c_dev *dev, u16 flags)
         timeout = wait_for_completion_timeout(
                 &dev->xfer_complete, dev->adap.timeout);
 
-        if (timeout < 0) {
-                dev_err(&dev->adev->dev,
-                        "wait_for_completion_timeout "
-                        "returned %d waiting for event\n", timeout);
-                status = timeout;
-        }
-
         if (timeout == 0) {
                 /* Controller timed out */
                 dev_err(&dev->adev->dev, "read from slave 0x%x timed out\n",
@@ -523,13 +516,6 @@ static int write_i2c(struct nmk_i2c_dev *dev, u16 flags)
         timeout = wait_for_completion_timeout(
                 &dev->xfer_complete, dev->adap.timeout);
 
-        if (timeout < 0) {
-                dev_err(&dev->adev->dev,
-                        "wait_for_completion_timeout "
-                        "returned %d waiting for event\n", timeout);
-                status = timeout;
-        }
-
         if (timeout == 0) {
                 /* Controller timed out */
                 dev_err(&dev->adev->dev, "write to slave 0x%x timed out\n",
diff --git a/drivers/i2c/busses/i2c-ocores.c b/drivers/i2c/busses/i2c-ocores.c
index 15da1ac7cf9..9b35c9fbb2f 100644
--- a/drivers/i2c/busses/i2c-ocores.c
+++ b/drivers/i2c/busses/i2c-ocores.c
@@ -4,6 +4,9 @@
  *
  * Peter Korsgaard <jacmet@sunsite.dk>
  *
+ * Support for the GRLIB port of the controller by
+ * Andreas Larsson <andreas@gaisler.com>
+ *
  * This file is licensed under the terms of the GNU General Public License
  * version 2.  This program is licensed "as is" without any warranty of any
  * kind, whether express or implied.
@@ -34,6 +37,8 @@ struct ocores_i2c {
         int nmsgs;
         int state; /* see STATE_ */
         int clock_khz;
+        void (*setreg)(struct ocores_i2c *i2c, int reg, u8 value);
+        u8 (*getreg)(struct ocores_i2c *i2c, int reg);
 };
 
 /* registers */
@@ -67,24 +72,47 @@ struct ocores_i2c {
 #define STATE_READ              3
 #define STATE_ERROR             4
 
+#define TYPE_OCORES             0
+#define TYPE_GRLIB              1
+
+static void oc_setreg_8(struct ocores_i2c *i2c, int reg, u8 value)
+{
+        iowrite8(value, i2c->base + (reg << i2c->reg_shift));
+}
+
+static void oc_setreg_16(struct ocores_i2c *i2c, int reg, u8 value)
+{
+        iowrite16(value, i2c->base + (reg << i2c->reg_shift));
+}
+
+static void oc_setreg_32(struct ocores_i2c *i2c, int reg, u8 value)
+{
+        iowrite32(value, i2c->base + (reg << i2c->reg_shift));
+}
+
+static inline u8 oc_getreg_8(struct ocores_i2c *i2c, int reg)
+{
+        return ioread8(i2c->base + (reg << i2c->reg_shift));
+}
+
+static inline u8 oc_getreg_16(struct ocores_i2c *i2c, int reg)
+{
+        return ioread16(i2c->base + (reg << i2c->reg_shift));
+}
+
+static inline u8 oc_getreg_32(struct ocores_i2c *i2c, int reg)
+{
+        return ioread32(i2c->base + (reg << i2c->reg_shift));
+}
+
 static inline void oc_setreg(struct ocores_i2c *i2c, int reg, u8 value)
 {
-        if (i2c->reg_io_width == 4)
-                iowrite32(value, i2c->base + (reg << i2c->reg_shift));
-        else if (i2c->reg_io_width == 2)
-                iowrite16(value, i2c->base + (reg << i2c->reg_shift));
-        else
-                iowrite8(value, i2c->base + (reg << i2c->reg_shift));
+        i2c->setreg(i2c, reg, value);
 }
 
 static inline u8 oc_getreg(struct ocores_i2c *i2c, int reg)
 {
-        if (i2c->reg_io_width == 4)
-                return ioread32(i2c->base + (reg << i2c->reg_shift));
-        else if (i2c->reg_io_width == 2)
-                return ioread16(i2c->base + (reg << i2c->reg_shift));
-        else
-                return ioread8(i2c->base + (reg << i2c->reg_shift));
+        return i2c->getreg(i2c, reg);
 }
 
 static void ocores_process(struct ocores_i2c *i2c)
@@ -223,11 +251,59 @@ static struct i2c_adapter ocores_adapter = {
         .algo           = &ocores_algorithm,
 };
 
+static struct of_device_id ocores_i2c_match[] = {
+        {
+                .compatible = "opencores,i2c-ocores",
+                .data = (void *)TYPE_OCORES,
+        },
+        {
+                .compatible = "aeroflexgaisler,i2cmst",
+                .data = (void *)TYPE_GRLIB,
+        },
+        {},
+};
+MODULE_DEVICE_TABLE(of, ocores_i2c_match);
+
 #ifdef CONFIG_OF
+/* Read and write functions for the GRLIB port of the controller. Registers are
+ * 32-bit big endian and the PRELOW and PREHIGH registers are merged into one
+ * register. The subsequent registers has their offset decreased accordingly. */
+static u8 oc_getreg_grlib(struct ocores_i2c *i2c, int reg)
+{
+        u32 rd;
+        int rreg = reg;
+        if (reg != OCI2C_PRELOW)
+                rreg--;
+        rd = ioread32be(i2c->base + (rreg << i2c->reg_shift));
+        if (reg == OCI2C_PREHIGH)
+                return (u8)(rd >> 8);
+        else
+                return (u8)rd;
+}
+
+static void oc_setreg_grlib(struct ocores_i2c *i2c, int reg, u8 value)
+{
+        u32 curr, wr;
+        int rreg = reg;
+        if (reg != OCI2C_PRELOW)
+                rreg--;
+        if (reg == OCI2C_PRELOW || reg == OCI2C_PREHIGH) {
+                curr = ioread32be(i2c->base + (rreg << i2c->reg_shift));
+                if (reg == OCI2C_PRELOW)
+                        wr = (curr & 0xff00) | value;
+                else
+                        wr = (((u32)value) << 8) | (curr & 0xff);
+        } else {
+                wr = value;
+        }
+        iowrite32be(wr, i2c->base + (rreg << i2c->reg_shift));
+}
+
 static int ocores_i2c_of_probe(struct platform_device *pdev,
                                 struct ocores_i2c *i2c)
 {
         struct device_node *np = pdev->dev.of_node;
+        const struct of_device_id *match;
         u32 val;
 
         if (of_property_read_u32(np, "reg-shift", &i2c->reg_shift)) {
@@ -253,6 +329,14 @@ static int ocores_i2c_of_probe(struct platform_device *pdev,
 
         of_property_read_u32(pdev->dev.of_node, "reg-io-width",
                                 &i2c->reg_io_width);
+
+        match = of_match_node(ocores_i2c_match, pdev->dev.of_node);
+        if (match && (int)match->data == TYPE_GRLIB) {
+                dev_dbg(&pdev->dev, "GRLIB variant of i2c-ocores\n");
+                i2c->setreg = oc_setreg_grlib;
+                i2c->getreg = oc_getreg_grlib;
+        }
+
         return 0;
 }
 #else
@@ -263,7 +347,8 @@ static int __devinit ocores_i2c_probe(struct platform_device *pdev)
 {
         struct ocores_i2c *i2c;
         struct ocores_i2c_platform_data *pdata;
-        struct resource *res, *res2;
+        struct resource *res;
+        int irq;
         int ret;
         int i;
 
@@ -271,26 +356,17 @@ static int __devinit ocores_i2c_probe(struct platform_device *pdev)
         if (!res)
                 return -ENODEV;
 
-        res2 = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
-        if (!res2)
-                return -ENODEV;
+        irq = platform_get_irq(pdev, 0);
+        if (irq < 0)
+                return irq;
 
         i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
         if (!i2c)
                 return -ENOMEM;
 
-        if (!devm_request_mem_region(&pdev->dev, res->start,
-                                     resource_size(res), pdev->name)) {
-                dev_err(&pdev->dev, "Memory region busy\n");
-                return -EBUSY;
-        }
-
-        i2c->base = devm_ioremap_nocache(&pdev->dev, res->start,
-                                         resource_size(res));
-        if (!i2c->base) {
-                dev_err(&pdev->dev, "Unable to map registers\n");
-                return -EIO;
-        }
+        i2c->base = devm_request_and_ioremap(&pdev->dev, res);
+        if (!i2c->base)
+                return -EADDRNOTAVAIL;
 
         pdata = pdev->dev.platform_data;
         if (pdata) {
@@ -306,10 +382,34 @@ static int __devinit ocores_i2c_probe(struct platform_device *pdev)
         if (i2c->reg_io_width == 0)
                 i2c->reg_io_width = 1; /* Set to default value */
 
+        if (!i2c->setreg || !i2c->getreg) {
+                switch (i2c->reg_io_width) {
+                case 1:
+                        i2c->setreg = oc_setreg_8;
+                        i2c->getreg = oc_getreg_8;
+                        break;
+
+                case 2:
+                        i2c->setreg = oc_setreg_16;
+                        i2c->getreg = oc_getreg_16;
+                        break;
+
+                case 4:
+                        i2c->setreg = oc_setreg_32;
+                        i2c->getreg = oc_getreg_32;
+                        break;
+
+                default:
+                        dev_err(&pdev->dev, "Unsupported I/O width (%d)\n",
+                                i2c->reg_io_width);
+                        return -EINVAL;
+                }
+        }
+
         ocores_init(i2c);
 
         init_waitqueue_head(&i2c->wait);
-        ret = devm_request_irq(&pdev->dev, res2->start, ocores_isr, 0,
+        ret = devm_request_irq(&pdev->dev, irq, ocores_isr, 0,
                                pdev->name, i2c);
         if (ret) {
                 dev_err(&pdev->dev, "Cannot claim IRQ\n");
@@ -383,12 +483,6 @@ static SIMPLE_DEV_PM_OPS(ocores_i2c_pm, ocores_i2c_suspend, ocores_i2c_resume);
 #define OCORES_I2C_PM   NULL
 #endif
 
-static struct of_device_id ocores_i2c_match[] = {
-        { .compatible = "opencores,i2c-ocores", },
-        {},
-};
-MODULE_DEVICE_TABLE(of, ocores_i2c_match);
-
 static struct platform_driver ocores_i2c_driver = {
         .probe   = ocores_i2c_probe,
         .remove  = __devexit_p(ocores_i2c_remove),
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 3525c9e62cb..7a62acb7d26 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -43,14 +43,16 @@
 #include <linux/slab.h>
 #include <linux/i2c-omap.h>
 #include <linux/pm_runtime.h>
+#include <linux/pinctrl/consumer.h>
 
 /* I2C controller revisions */
 #define OMAP_I2C_OMAP1_REV_2            0x20
 
 /* I2C controller revisions present on specific hardware */
-#define OMAP_I2C_REV_ON_2430            0x36
-#define OMAP_I2C_REV_ON_3430_3530       0x3C
-#define OMAP_I2C_REV_ON_3630_4430       0x40
+#define OMAP_I2C_REV_ON_2430            0x00000036
+#define OMAP_I2C_REV_ON_3430_3530       0x0000003C
+#define OMAP_I2C_REV_ON_3630            0x00000040
+#define OMAP_I2C_REV_ON_4430_PLUS       0x50400002
 
 /* timeout waiting for the controller to respond */
 #define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000))
@@ -190,7 +192,6 @@ struct omap_i2c_dev {
         void                    (*set_mpu_wkup_lat)(struct device *dev,
                                                     long latency);
         u32                     speed;          /* Speed of bus in kHz */
-        u32                     dtrev;          /* extra revision from DT */
         u32                     flags;
         u16                     cmd_err;
         u8                      *buf;
@@ -202,17 +203,18 @@ struct omap_i2c_dev {
                                                  * fifo_size==0 implies no fifo
                                                  * if set, should be trsh+1
                                                  */
-        u8                      rev;
+        u32                     rev;
         unsigned                b_hw:1;         /* bad h/w fixes */
         unsigned                receiver:1;     /* true when we're in receiver mode */
         u16                     iestate;        /* Saved interrupt register */
         u16                     pscstate;
         u16                     scllstate;
         u16                     sclhstate;
-        u16                     bufstate;
         u16                     syscstate;
         u16                     westate;
         u16                     errata;
+
+        struct pinctrl          *pins;
 };
 
 static const u8 reg_map_ip_v1[] = {
@@ -275,16 +277,39 @@ static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
                                 (i2c_dev->regs[reg] << i2c_dev->reg_shift));
 }
 
-static int omap_i2c_init(struct omap_i2c_dev *dev)
+static void __omap_i2c_init(struct omap_i2c_dev *dev)
+{
+
+        omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
+
+        /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
+        omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
+
+        /* SCL low and high time values */
+        omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
+        omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate);
+        if (dev->rev >= OMAP_I2C_REV_ON_3430_3530)
+                omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
+
+        /* Take the I2C module out of reset: */
+        omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
+
+        /*
+         * Don't write to this register if the IE state is 0 as it can
+         * cause deadlock.
+         */
+        if (dev->iestate)
+                omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
+}
+
+static int omap_i2c_reset(struct omap_i2c_dev *dev)
 {
-        u16 psc = 0, scll = 0, sclh = 0, buf = 0;
-        u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
-        unsigned long fclk_rate = 12000000;
         unsigned long timeout;
-        unsigned long internal_clk = 0;
-        struct clk *fclk;
+        u16 sysc;
 
         if (dev->rev >= OMAP_I2C_OMAP1_REV_2) {
+                sysc = omap_i2c_read_reg(dev, OMAP_I2C_SYSC_REG);
+
                 /* Disable I2C controller before soft reset */
                 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
                         omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) &
@@ -306,32 +331,28 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
                 }
 
                 /* SYSC register is cleared by the reset; rewrite it */
-                if (dev->rev == OMAP_I2C_REV_ON_2430) {
-
-                        omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
-                                           SYSC_AUTOIDLE_MASK);
-
-                } else if (dev->rev >= OMAP_I2C_REV_ON_3430_3530) {
-                        dev->syscstate = SYSC_AUTOIDLE_MASK;
-                        dev->syscstate |= SYSC_ENAWAKEUP_MASK;
-                        dev->syscstate |= (SYSC_IDLEMODE_SMART <<
-                              __ffs(SYSC_SIDLEMODE_MASK));
-                        dev->syscstate |= (SYSC_CLOCKACTIVITY_FCLK <<
-                              __ffs(SYSC_CLOCKACTIVITY_MASK));
-
-                        omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
-                                                        dev->syscstate);
-                        /*
-                         * Enabling all wakup sources to stop I2C freezing on
-                         * WFI instruction.
-                         * REVISIT: Some wkup sources might not be needed.
-                         */
-                        dev->westate = OMAP_I2C_WE_ALL;
-                        omap_i2c_write_reg(dev, OMAP_I2C_WE_REG,
-                                                        dev->westate);
-                }
+                omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, sysc);
+
+        }
+        return 0;
+}
+
+static int omap_i2c_init(struct omap_i2c_dev *dev)
+{
+        u16 psc = 0, scll = 0, sclh = 0;
+        u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
+        unsigned long fclk_rate = 12000000;
+        unsigned long internal_clk = 0;
+        struct clk *fclk;
+
+        if (dev->rev >= OMAP_I2C_REV_ON_3430_3530) {
+                /*
+                 * Enabling all wakup sources to stop I2C freezing on
+                 * WFI instruction.
+                 * REVISIT: Some wkup sources might not be needed.
+                 */
+                dev->westate = OMAP_I2C_WE_ALL;
         }
-        omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
 
         if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
                 /*
@@ -416,28 +437,17 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
                 sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
         }
 
-        /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
-        omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
-
-        /* SCL low and high time values */
-        omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
-        omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
-
-        /* Take the I2C module out of reset: */
-        omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
-
-        /* Enable interrupts */
         dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
                         OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK |
                         OMAP_I2C_IE_AL)  | ((dev->fifo_size) ?
                                 (OMAP_I2C_IE_RDR | OMAP_I2C_IE_XDR) : 0);
-        omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
-        if (dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
-                dev->pscstate = psc;
-                dev->scllstate = scll;
-                dev->sclhstate = sclh;
-                dev->bufstate = buf;
-        }
+
+        dev->pscstate = psc;
+        dev->scllstate = scll;
+        dev->sclhstate = sclh;
+
+        __omap_i2c_init(dev);
+
         return 0;
 }
 
@@ -490,7 +500,7 @@ static void omap_i2c_resize_fifo(struct omap_i2c_dev *dev, u8 size, bool is_rx)
 
         omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf);
 
-        if (dev->rev < OMAP_I2C_REV_ON_3630_4430)
+        if (dev->rev < OMAP_I2C_REV_ON_3630)
                 dev->b_hw = 1; /* Enable hardware fixes */
 
         /* calculate wakeup latency constraint for MPU */
@@ -586,7 +596,8 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
                                                 OMAP_I2C_TIMEOUT);
         if (timeout == 0) {
                 dev_err(dev->dev, "controller timed out\n");
-                omap_i2c_init(dev);
+                omap_i2c_reset(dev);
+                __omap_i2c_init(dev);
                 return -ETIMEDOUT;
         }
 
@@ -596,7 +607,8 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
         /* We have an error */
         if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR |
                             OMAP_I2C_STAT_XUDF)) {
-                omap_i2c_init(dev);
+                omap_i2c_reset(dev);
+                __omap_i2c_init(dev);
                 return -EIO;
         }
 
@@ -642,13 +654,14 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
                         break;
         }
 
-        if (dev->set_mpu_wkup_lat != NULL)
-                dev->set_mpu_wkup_lat(dev->dev, -1);
-
         if (r == 0)
                 r = num;
 
         omap_i2c_wait_for_bb(dev);
+
+        if (dev->set_mpu_wkup_lat != NULL)
+                dev->set_mpu_wkup_lat(dev->dev, -1);
+
 out:
         pm_runtime_mark_last_busy(dev->dev);
         pm_runtime_put_autosuspend(dev->dev);
@@ -1025,9 +1038,7 @@ static const struct i2c_algorithm omap_i2c_algo = {
 #ifdef CONFIG_OF
 static struct omap_i2c_bus_platform_data omap3_pdata = {
         .rev = OMAP_I2C_IP_VERSION_1,
-        .flags = OMAP_I2C_FLAG_APPLY_ERRATA_I207 |
-                 OMAP_I2C_FLAG_RESET_REGS_POSTIDLE |
-                 OMAP_I2C_FLAG_BUS_SHIFT_2,
+        .flags = OMAP_I2C_FLAG_BUS_SHIFT_2,
 };
 
 static struct omap_i2c_bus_platform_data omap4_pdata = {
@@ -1048,6 +1059,16 @@ static const struct of_device_id omap_i2c_of_match[] = {
 MODULE_DEVICE_TABLE(of, omap_i2c_of_match);
 #endif
 
+#define OMAP_I2C_SCHEME(rev)            ((rev & 0xc000) >> 14)
+
+#define OMAP_I2C_REV_SCHEME_0_MAJOR(rev) (rev >> 4)
+#define OMAP_I2C_REV_SCHEME_0_MINOR(rev) (rev & 0xf)
+
+#define OMAP_I2C_REV_SCHEME_1_MAJOR(rev) ((rev & 0x0700) >> 7)
+#define OMAP_I2C_REV_SCHEME_1_MINOR(rev) (rev & 0x1f)
+#define OMAP_I2C_SCHEME_0               0
+#define OMAP_I2C_SCHEME_1               1
+
 static int __devinit
 omap_i2c_probe(struct platform_device *pdev)
 {
@@ -1060,6 +1081,8 @@ omap_i2c_probe(struct platform_device *pdev)
         const struct of_device_id *match;
         int irq;
         int r;
+        u32 rev;
+        u16 minor, major, scheme;
 
         /* NOTE: driver uses the static register mapping */
         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -1091,7 +1114,6 @@ omap_i2c_probe(struct platform_device *pdev)
                 u32 freq = 100000; /* default to 100000 Hz */
 
                 pdata = match->data;
-                dev->dtrev = pdata->rev;
                 dev->flags = pdata->flags;
 
                 of_property_read_u32(node, "clock-frequency", &freq);
@@ -1101,7 +1123,16 @@ omap_i2c_probe(struct platform_device *pdev)
                 dev->speed = pdata->clkrate;
                 dev->flags = pdata->flags;
                 dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
-                dev->dtrev = pdata->rev;
+        }
+
+        dev->pins = devm_pinctrl_get_select_default(&pdev->dev);
+        if (IS_ERR(dev->pins)) {
+                if (PTR_ERR(dev->pins) == -EPROBE_DEFER)
+                        return -EPROBE_DEFER;
+
+                dev_warn(&pdev->dev, "did not get pins for i2c error: %li\n",
+                         PTR_ERR(dev->pins));
+                dev->pins = NULL;
         }
 
         dev->dev = &pdev->dev;
@@ -1114,11 +1145,6 @@ omap_i2c_probe(struct platform_device *pdev)
 
         dev->reg_shift = (dev->flags >> OMAP_I2C_FLAG_BUS_SHIFT__SHIFT) & 3;
 
-        if (dev->dtrev == OMAP_I2C_IP_VERSION_2)
-                dev->regs = (u8 *)reg_map_ip_v2;
-        else
-                dev->regs = (u8 *)reg_map_ip_v1;
-
         pm_runtime_enable(dev->dev);
         pm_runtime_set_autosuspend_delay(dev->dev, OMAP_I2C_PM_TIMEOUT);
         pm_runtime_use_autosuspend(dev->dev);
@@ -1127,11 +1153,37 @@ omap_i2c_probe(struct platform_device *pdev)
         if (IS_ERR_VALUE(r))
                 goto err_free_mem;
 
-        dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
+        /*
+         * Read the Rev hi bit-[15:14] ie scheme this is 1 indicates ver2.
+         * On omap1/3/2 Offset 4 is IE Reg the bit [15:14] is 0 at reset.
+         * Also since the omap_i2c_read_reg uses reg_map_ip_* a
+         * raw_readw is done.
+         */
+        rev = __raw_readw(dev->base + 0x04);
+
+        scheme = OMAP_I2C_SCHEME(rev);
+        switch (scheme) {
+        case OMAP_I2C_SCHEME_0:
+                dev->regs = (u8 *)reg_map_ip_v1;
+                dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG);
+                minor = OMAP_I2C_REV_SCHEME_0_MAJOR(dev->rev);
+                major = OMAP_I2C_REV_SCHEME_0_MAJOR(dev->rev);
+                break;
+        case OMAP_I2C_SCHEME_1:
+                /* FALLTHROUGH */
+        default:
+                dev->regs = (u8 *)reg_map_ip_v2;
+                rev = (rev << 16) |
+                        omap_i2c_read_reg(dev, OMAP_I2C_IP_V2_REVNB_LO);
+                minor = OMAP_I2C_REV_SCHEME_1_MINOR(rev);
+                major = OMAP_I2C_REV_SCHEME_1_MAJOR(rev);
+                dev->rev = rev;
+        }
 
         dev->errata = 0;
 
-        if (dev->flags & OMAP_I2C_FLAG_APPLY_ERRATA_I207)
+        if (dev->rev >= OMAP_I2C_REV_ON_2430 &&
+                        dev->rev < OMAP_I2C_REV_ON_4430_PLUS)
                 dev->errata |= I2C_OMAP_ERRATA_I207;
 
         if (dev->rev <= OMAP_I2C_REV_ON_3430_3530)
@@ -1152,7 +1204,7 @@ omap_i2c_probe(struct platform_device *pdev)
 
                 dev->fifo_size = (dev->fifo_size / 2);
 
-                if (dev->rev < OMAP_I2C_REV_ON_3630_4430)
+                if (dev->rev < OMAP_I2C_REV_ON_3630)
                         dev->b_hw = 1; /* Enable hardware fixes */
 
                 /* calculate wakeup latency constraint for MPU */
@@ -1195,8 +1247,8 @@ omap_i2c_probe(struct platform_device *pdev)
                 goto err_unuse_clocks;
         }
 
-        dev_info(dev->dev, "bus %d rev%d.%d.%d at %d kHz\n", adap->nr,
-                 dev->dtrev, dev->rev >> 4, dev->rev & 0xf, dev->speed);
+        dev_info(dev->dev, "bus %d rev%d.%d at %d kHz\n", adap->nr,
+                 major, minor, dev->speed);
 
         of_i2c_register_devices(adap);
 
@@ -1239,14 +1291,13 @@ static int omap_i2c_runtime_suspend(struct device *dev)
 {
         struct platform_device *pdev = to_platform_device(dev);
         struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
-        u16 iv;
 
         _dev->iestate = omap_i2c_read_reg(_dev, OMAP_I2C_IE_REG);
 
         omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, 0);
 
         if (_dev->rev < OMAP_I2C_OMAP1_REV_2) {
-                iv = omap_i2c_read_reg(_dev, OMAP_I2C_IV_REG); /* Read clears */
+                omap_i2c_read_reg(_dev, OMAP_I2C_IV_REG); /* Read clears */
         } else {
                 omap_i2c_write_reg(_dev, OMAP_I2C_STAT_REG, _dev->iestate);
 
@@ -1262,23 +1313,10 @@ static int omap_i2c_runtime_resume(struct device *dev)
         struct platform_device *pdev = to_platform_device(dev);
         struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
 
-        if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
-                omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
-                omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
-                omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
-                omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
-                omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
-                omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
-                omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
-                omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
-        }
+        if (!_dev->regs)
+                return 0;
 
-        /*
-         * Don't write to this register if the IE state is 0 as it can
-         * cause deadlock.
-         */
-        if (_dev->iestate)
-                omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);
+        __omap_i2c_init(_dev);
 
         return 0;
 }
diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c
index f9399d163af..72a8071a555 100644
--- a/drivers/i2c/busses/i2c-rcar.c
+++ b/drivers/i2c/busses/i2c-rcar.c
@@ -642,7 +642,7 @@ static int __devinit rcar_i2c_probe(struct platform_device *pdev)
         if (ret < 0)
                 return ret;
 
-        priv->io = devm_ioremap(dev, res->start, resource_size(res));
+        priv->io = devm_request_and_ioremap(dev, res);
         if (!priv->io) {
                 dev_err(dev, "cannot ioremap\n");
                 return -ENODEV;
@@ -693,7 +693,7 @@ static int __devexit rcar_i2c_remove(struct platform_device *pdev)
         return 0;
 }
 
-static struct platform_driver rcar_i2c_drv = {
+static struct platform_driver rcar_i2c_driver = {
         .driver = {
                 .name   = "i2c-rcar",
                 .owner  = THIS_MODULE,
@@ -702,7 +702,7 @@ static struct platform_driver rcar_i2c_drv = {
         .remove         = __devexit_p(rcar_i2c_remove),
 };
 
-module_platform_driver(rcar_i2c_drv);
+module_platform_driver(rcar_i2c_driver);
 
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("Renesas R-Car I2C bus driver");
diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c
index b33d95ebc89..a290d089cea 100644
--- a/drivers/i2c/busses/i2c-s3c2410.c
+++ b/drivers/i2c/busses/i2c-s3c2410.c
@@ -38,6 +38,7 @@
 #include <linux/io.h>
 #include <linux/of_i2c.h>
 #include <linux/of_gpio.h>
+#include <linux/pinctrl/consumer.h>
 
 #include <asm/irq.h>
 
@@ -49,6 +50,9 @@
 #define QUIRK_HDMIPHY           (1 << 1)
 #define QUIRK_NO_GPIO           (1 << 2)
 
+/* Max time to wait for bus to become idle after a xfer (in us) */
+#define S3C2410_IDLE_TIMEOUT    5000
+
 /* i2c controller state */
 enum s3c24xx_i2c_state {
         STATE_IDLE,
@@ -59,7 +63,6 @@ enum s3c24xx_i2c_state {
 };
 
 struct s3c24xx_i2c {
-        spinlock_t              lock;
         wait_queue_head_t       wait;
         unsigned int            quirks;
         unsigned int            suspended:1;
@@ -78,11 +81,11 @@ struct s3c24xx_i2c {
         void __iomem            *regs;
         struct clk              *clk;
         struct device           *dev;
-        struct resource         *ioarea;
         struct i2c_adapter      adap;
 
         struct s3c2410_platform_i2c     *pdata;
         int                     gpios[2];
+        struct pinctrl          *pctrl;
 #ifdef CONFIG_CPU_FREQ
         struct notifier_block   freq_transition;
 #endif
@@ -235,8 +238,47 @@ static inline void s3c24xx_i2c_stop(struct s3c24xx_i2c *i2c, int ret)
 
         dev_dbg(i2c->dev, "STOP\n");
 
-        /* stop the transfer */
-        iicstat &= ~S3C2410_IICSTAT_START;
+        /*
+         * The datasheet says that the STOP sequence should be:
+         *  1) I2CSTAT.5 = 0    - Clear BUSY (or 'generate STOP')
+         *  2) I2CCON.4 = 0     - Clear IRQPEND
+         *  3) Wait until the stop condition takes effect.
+         *  4*) I2CSTAT.4 = 0   - Clear TXRXEN
+         *
+         * Where, step "4*" is only for buses with the "HDMIPHY" quirk.
+         *
+         * However, after much experimentation, it appears that:
+         * a) normal buses automatically clear BUSY and transition from
+         *    Master->Slave when they complete generating a STOP condition.
+         *    Therefore, step (3) can be done in doxfer() by polling I2CCON.4
+         *    after starting the STOP generation here.
+         * b) HDMIPHY bus does neither, so there is no way to do step 3.
+         *    There is no indication when this bus has finished generating
+         *    STOP.
+         *
+         * In fact, we have found that as soon as the IRQPEND bit is cleared in
+         * step 2, the HDMIPHY bus generates the STOP condition, and then
+         * immediately starts transferring another data byte, even though the
+         * bus is supposedly stopped.  This is presumably because the bus is
+         * still in "Master" mode, and its BUSY bit is still set.
+         *
+         * To avoid these extra post-STOP transactions on HDMI phy devices, we
+         * just disable Serial Output on the bus (I2CSTAT.4 = 0) directly,
+         * instead of first generating a proper STOP condition.  This should
+         * float SDA & SCK terminating the transfer.  Subsequent transfers
+         *  start with a proper START condition, and proceed normally.
+         *
+         * The HDMIPHY bus is an internal bus that always has exactly two
+         * devices, the host as Master and the HDMIPHY device as the slave.
+         * Skipping the STOP condition has been tested on this bus and works.
+         */
+        if (i2c->quirks & QUIRK_HDMIPHY) {
+                /* Stop driving the I2C pins */
+                iicstat &= ~S3C2410_IICSTAT_TXRXEN;
+        } else {
+                /* stop the transfer */
+                iicstat &= ~S3C2410_IICSTAT_START;
+        }
         writel(iicstat, i2c->regs + S3C2410_IICSTAT);
 
         i2c->state = STATE_STOP;
@@ -490,13 +532,6 @@ static int s3c24xx_i2c_set_master(struct s3c24xx_i2c *i2c)
         unsigned long iicstat;
         int timeout = 400;
 
-        /* the timeout for HDMIPHY is reduced to 10 ms because
-         * the hangup is expected to happen, so waiting 400 ms
-         * causes only unnecessary system hangup
-         */
-        if (i2c->quirks & QUIRK_HDMIPHY)
-                timeout = 10;
-
         while (timeout-- > 0) {
                 iicstat = readl(i2c->regs + S3C2410_IICSTAT);
 
@@ -506,16 +541,61 @@ static int s3c24xx_i2c_set_master(struct s3c24xx_i2c *i2c)
                 msleep(1);
         }
 
-        /* hang-up of bus dedicated for HDMIPHY occurred, resetting */
-        if (i2c->quirks & QUIRK_HDMIPHY) {
-                writel(0, i2c->regs + S3C2410_IICCON);
-                writel(0, i2c->regs + S3C2410_IICSTAT);
-                writel(0, i2c->regs + S3C2410_IICDS);
+        return -ETIMEDOUT;
+}
 
-                return 0;
+/* s3c24xx_i2c_wait_idle
+ *
+ * wait for the i2c bus to become idle.
+*/
+
+static void s3c24xx_i2c_wait_idle(struct s3c24xx_i2c *i2c)
+{
+        unsigned long iicstat;
+        ktime_t start, now;
+        unsigned long delay;
+        int spins;
+
+        /* ensure the stop has been through the bus */
+
+        dev_dbg(i2c->dev, "waiting for bus idle\n");
+
+        start = now = ktime_get();
+
+        /*
+         * Most of the time, the bus is already idle within a few usec of the
+         * end of a transaction.  However, really slow i2c devices can stretch
+         * the clock, delaying STOP generation.
+         *
+         * On slower SoCs this typically happens within a very small number of
+         * instructions so busy wait briefly to avoid scheduling overhead.
+         */
+        spins = 3;
+        iicstat = readl(i2c->regs + S3C2410_IICSTAT);
+        while ((iicstat & S3C2410_IICSTAT_START) && --spins) {
+                cpu_relax();
+                iicstat = readl(i2c->regs + S3C2410_IICSTAT);
         }
 
-        return -ETIMEDOUT;
+        /*
+         * If we do get an appreciable delay as a compromise between idle
+         * detection latency for the normal, fast case, and system load in the
+         * slow device case, use an exponential back off in the polling loop,
+         * up to 1/10th of the total timeout, then continue to poll at a
+         * constant rate up to the timeout.
+         */
+        delay = 1;
+        while ((iicstat & S3C2410_IICSTAT_START) &&
+               ktime_us_delta(now, start) < S3C2410_IDLE_TIMEOUT) {
+                usleep_range(delay, 2 * delay);
+                if (delay < S3C2410_IDLE_TIMEOUT / 10)
+                        delay <<= 1;
+                now = ktime_get();
+                iicstat = readl(i2c->regs + S3C2410_IICSTAT);
+        }
+
+        if (iicstat & S3C2410_IICSTAT_START)
+                dev_warn(i2c->dev, "timeout waiting for bus idle\n");
 }
 
 /* s3c24xx_i2c_doxfer
@@ -526,8 +606,7 @@ static int s3c24xx_i2c_set_master(struct s3c24xx_i2c *i2c)
 static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c,
                               struct i2c_msg *msgs, int num)
 {
-        unsigned long iicstat, timeout;
-        int spins = 20;
+        unsigned long timeout;
         int ret;
 
         if (i2c->suspended)
@@ -540,8 +619,6 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c,
                 goto out;
         }
 
-        spin_lock_irq(&i2c->lock);
-
         i2c->msg     = msgs;
         i2c->msg_num = num;
         i2c->msg_ptr = 0;
@@ -550,7 +627,6 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c,
 
         s3c24xx_i2c_enable_irq(i2c);
         s3c24xx_i2c_message_start(i2c, msgs);
-        spin_unlock_irq(&i2c->lock);
 
         timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5);
 
@@ -564,24 +640,11 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c,
         else if (ret != num)
                 dev_dbg(i2c->dev, "incomplete xfer (%d)\n", ret);
 
-        /* ensure the stop has been through the bus */
-
-        dev_dbg(i2c->dev, "waiting for bus idle\n");
-
-        /* first, try busy waiting briefly */
-        do {
-                cpu_relax();
-                iicstat = readl(i2c->regs + S3C2410_IICSTAT);
-        } while ((iicstat & S3C2410_IICSTAT_START) && --spins);
-
-        /* if that timed out sleep */
-        if (!spins) {
-                msleep(1);
-                iicstat = readl(i2c->regs + S3C2410_IICSTAT);
-        }
+        /* For QUIRK_HDMIPHY, bus is already disabled */
+        if (i2c->quirks & QUIRK_HDMIPHY)
+                goto out;
 
-        if (iicstat & S3C2410_IICSTAT_START)
-                dev_warn(i2c->dev, "timeout waiting for bus idle\n");
+        s3c24xx_i2c_wait_idle(i2c);
 
  out:
         return ret;
@@ -740,7 +803,6 @@ static int s3c24xx_i2c_cpufreq_transition(struct notifier_block *nb,
                                           unsigned long val, void *data)
 {
         struct s3c24xx_i2c *i2c = freq_to_i2c(nb);
-        unsigned long flags;
         unsigned int got;
         int delta_f;
         int ret;
@@ -754,9 +816,9 @@ static int s3c24xx_i2c_cpufreq_transition(struct notifier_block *nb,
 
         if ((val == CPUFREQ_POSTCHANGE && delta_f < 0) ||
             (val == CPUFREQ_PRECHANGE && delta_f > 0)) {
-                spin_lock_irqsave(&i2c->lock, flags);
+                i2c_lock_adapter(&i2c->adap);
                 ret = s3c24xx_i2c_clockrate(i2c, &got);
-                spin_unlock_irqrestore(&i2c->lock, flags);
+                i2c_unlock_adapter(&i2c->adap);
 
                 if (ret < 0)
                         dev_err(i2c->dev, "cannot find frequency\n");
@@ -858,14 +920,6 @@ static int s3c24xx_i2c_init(struct s3c24xx_i2c *i2c)
 
         pdata = i2c->pdata;
 
-        /* inititalise the gpio */
-
-        if (pdata->cfg_gpio)
-                pdata->cfg_gpio(to_platform_device(i2c->dev));
-        else
-                if (s3c24xx_i2c_parse_dt_gpio(i2c))
-                        return -EINVAL;
-
         /* write slave address */
 
         writeb(pdata->slave_addr, i2c->regs + S3C2410_IICADD);
@@ -963,7 +1017,6 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev)
         i2c->adap.class   = I2C_CLASS_HWMON | I2C_CLASS_SPD;
         i2c->tx_setup     = 50;
 
-        spin_lock_init(&i2c->lock);
         init_waitqueue_head(&i2c->wait);
 
         /* find the clock and enable it */
@@ -989,36 +1042,38 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev)
                 goto err_clk;
         }
 
-        i2c->ioarea = request_mem_region(res->start, resource_size(res),
-                                         pdev->name);
-
-        if (i2c->ioarea == NULL) {
-                dev_err(&pdev->dev, "cannot request IO\n");
-                ret = -ENXIO;
-                goto err_clk;
-        }
-
-        i2c->regs = ioremap(res->start, resource_size(res));
+        i2c->regs = devm_request_and_ioremap(&pdev->dev, res);
 
         if (i2c->regs == NULL) {
                 dev_err(&pdev->dev, "cannot map IO\n");
                 ret = -ENXIO;
-                goto err_ioarea;
+                goto err_clk;
         }
 
-        dev_dbg(&pdev->dev, "registers %p (%p, %p)\n",
-                i2c->regs, i2c->ioarea, res);
+        dev_dbg(&pdev->dev, "registers %p (%p)\n",
+                i2c->regs, res);
 
         /* setup info block for the i2c core */
 
         i2c->adap.algo_data = i2c;
         i2c->adap.dev.parent = &pdev->dev;
 
+        i2c->pctrl = devm_pinctrl_get_select_default(i2c->dev);
+
+        /* inititalise the i2c gpio lines */
+
+        if (i2c->pdata->cfg_gpio) {
+                i2c->pdata->cfg_gpio(to_platform_device(i2c->dev));
+        } else if (IS_ERR(i2c->pctrl) && s3c24xx_i2c_parse_dt_gpio(i2c)) {
+                ret = -EINVAL;
+                goto err_clk;
+        }
+
         /* initialise the i2c controller */
 
         ret = s3c24xx_i2c_init(i2c);
         if (ret != 0)
-                goto err_iomap;
+                goto err_clk;
 
         /* find the IRQ for this unit (note, this relies on the init call to
          * ensure no current IRQs pending
@@ -1027,7 +1082,7 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev)
         i2c->irq = ret = platform_get_irq(pdev, 0);
         if (ret <= 0) {
                 dev_err(&pdev->dev, "cannot find IRQ\n");
-                goto err_iomap;
+                goto err_clk;
         }
 
         ret = request_irq(i2c->irq, s3c24xx_i2c_irq, 0,
@@ -1035,7 +1090,7 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev)
 
         if (ret != 0) {
                 dev_err(&pdev->dev, "cannot claim IRQ %d\n", i2c->irq);
-                goto err_iomap;
+                goto err_clk;
         }
 
         ret = s3c24xx_i2c_register_cpufreq(i2c);
@@ -1075,13 +1130,6 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev)
  err_irq:
         free_irq(i2c->irq, i2c);
 
- err_iomap:
-        iounmap(i2c->regs);
-
- err_ioarea:
-        release_resource(i2c->ioarea);
-        kfree(i2c->ioarea);
-
  err_clk:
         clk_disable_unprepare(i2c->clk);
         clk_put(i2c->clk);
@@ -1110,16 +1158,13 @@ static int s3c24xx_i2c_remove(struct platform_device *pdev)
         clk_disable_unprepare(i2c->clk);
         clk_put(i2c->clk);
 
-        iounmap(i2c->regs);
-
-        release_resource(i2c->ioarea);
-        s3c24xx_i2c_dt_gpio_free(i2c);
-        kfree(i2c->ioarea);
+        if (pdev->dev.of_node && IS_ERR(i2c->pctrl))
+                s3c24xx_i2c_dt_gpio_free(i2c);
 
         return 0;
 }
 
-#ifdef CONFIG_PM
+#ifdef CONFIG_PM_SLEEP
 static int s3c24xx_i2c_suspend_noirq(struct device *dev)
 {
         struct platform_device *pdev = to_platform_device(dev);
@@ -1142,10 +1187,14 @@ static int s3c24xx_i2c_resume(struct device *dev)
 
         return 0;
 }
+#endif
 
+#ifdef CONFIG_PM
 static const struct dev_pm_ops s3c24xx_i2c_dev_pm_ops = {
+#ifdef CONFIG_PM_SLEEP
         .suspend_noirq = s3c24xx_i2c_suspend_noirq,
         .resume = s3c24xx_i2c_resume,
+#endif
 };
 
 #define S3C24XX_DEV_PM_OPS (&s3c24xx_i2c_dev_pm_ops)
diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c
index 8110ca45f34..9411c1b892c 100644
--- a/drivers/i2c/busses/i2c-sh_mobile.c
+++ b/drivers/i2c/busses/i2c-sh_mobile.c
@@ -120,11 +120,12 @@ struct sh_mobile_i2c_data {
         void __iomem *reg;
         struct i2c_adapter adap;
         unsigned long bus_speed;
+        unsigned int clks_per_count;
         struct clk *clk;
         u_int8_t icic;
-        u_int8_t iccl;
-        u_int8_t icch;
         u_int8_t flags;
+        u_int16_t iccl;
+        u_int16_t icch;
 
         spinlock_t lock;
         wait_queue_head_t wait;
@@ -135,7 +136,8 @@ struct sh_mobile_i2c_data {
 
 #define IIC_FLAG_HAS_ICIC67     (1 << 0)
 
-#define NORMAL_SPEED            100000 /* FAST_SPEED 400000 */
+#define STANDARD_MODE           100000
+#define FAST_MODE               400000
 
 /* Register offsets */
 #define ICDR                    0x00
@@ -187,57 +189,90 @@ static void iic_set_clr(struct sh_mobile_i2c_data *pd, int offs,
         iic_wr(pd, offs, (iic_rd(pd, offs) | set) & ~clr);
 }
 
-static void activate_ch(struct sh_mobile_i2c_data *pd)
+static u32 sh_mobile_i2c_iccl(unsigned long count_khz, u32 tLOW, u32 tf, int offset)
 {
-        unsigned long i2c_clk;
-        u_int32_t num;
-        u_int32_t denom;
-        u_int32_t tmp;
-
-        /* Wake up device and enable clock */
-        pm_runtime_get_sync(pd->dev);
-        clk_enable(pd->clk);
-
-        /* Get clock rate after clock is enabled */
-        i2c_clk = clk_get_rate(pd->clk);
+        /*
+         * Conditional expression:
+         *   ICCL >= COUNT_CLK * (tLOW + tf)
+         *
+         * SH-Mobile IIC hardware starts counting the LOW period of
+         * the SCL signal (tLOW) as soon as it pulls the SCL line.
+         * In order to meet the tLOW timing spec, we need to take into
+         * account the fall time of SCL signal (tf).  Default tf value
+         * should be 0.3 us, for safety.
+         */
+        return (((count_khz * (tLOW + tf)) + 5000) / 10000) + offset;
+}
 
-        /* Calculate the value for iccl. From the data sheet:
-         * iccl = (p clock / transfer rate) * (L / (L + H))
-         * where L and H are the SCL low/high ratio (5/4 in this case).
-         * We also round off the result.
+static u32 sh_mobile_i2c_icch(unsigned long count_khz, u32 tHIGH, u32 tf, int offset)
+{
+        /*
+         * Conditional expression:
+         *   ICCH >= COUNT_CLK * (tHIGH + tf)
+         *
+         * SH-Mobile IIC hardware is aware of SCL transition period 'tr',
+         * and can ignore it.  SH-Mobile IIC controller starts counting
+         * the HIGH period of the SCL signal (tHIGH) after the SCL input
+         * voltage increases at VIH.
+         *
+         * Afterward it turned out calculating ICCH using only tHIGH spec
+         * will result in violation of the tHD;STA timing spec.  We need
+         * to take into account the fall time of SDA signal (tf) at START
+         * condition, in order to meet both tHIGH and tHD;STA specs.
          */
-        num = i2c_clk * 5;
-        denom = pd->bus_speed * 9;
-        tmp = num * 10 / denom;
-        if (tmp % 10 >= 5)
-                pd->iccl = (u_int8_t)((num/denom) + 1);
-        else
-                pd->iccl = (u_int8_t)(num/denom);
+        return (((count_khz * (tHIGH + tf)) + 5000) / 10000) + offset;
+}
 
-        /* one more bit of ICCL in ICIC */
-        if (pd->flags & IIC_FLAG_HAS_ICIC67) {
-                if ((num/denom) > 0xff)
-                        pd->icic |= ICIC_ICCLB8;
-                else
-                        pd->icic &= ~ICIC_ICCLB8;
+static void sh_mobile_i2c_init(struct sh_mobile_i2c_data *pd)
+{
+        unsigned long i2c_clk_khz;
+        u32 tHIGH, tLOW, tf;
+        int offset;
+
+        /* Get clock rate after clock is enabled */
+        clk_enable(pd->clk);
+        i2c_clk_khz = clk_get_rate(pd->clk) / 1000;
+        i2c_clk_khz /= pd->clks_per_count;
+
+        if (pd->bus_speed == STANDARD_MODE) {
+                tLOW    = 47;   /* tLOW = 4.7 us */
+                tHIGH   = 40;   /* tHD;STA = tHIGH = 4.0 us */
+                tf      = 3;    /* tf = 0.3 us */
+                offset  = 0;    /* No offset */
+        } else if (pd->bus_speed == FAST_MODE) {
+                tLOW    = 13;   /* tLOW = 1.3 us */
+                tHIGH   = 6;    /* tHD;STA = tHIGH = 0.6 us */
+                tf      = 3;    /* tf = 0.3 us */
+                offset  = 0;    /* No offset */
+        } else {
+                dev_err(pd->dev, "unrecognized bus speed %lu Hz\n",
+                        pd->bus_speed);
+                goto out;
         }
 
-        /* Calculate the value for icch. From the data sheet:
-           icch = (p clock / transfer rate) * (H / (L + H)) */
-        num = i2c_clk * 4;
-        tmp = num * 10 / denom;
-        if (tmp % 10 >= 5)
-                pd->icch = (u_int8_t)((num/denom) + 1);
+        pd->iccl = sh_mobile_i2c_iccl(i2c_clk_khz, tLOW, tf, offset);
+        /* one more bit of ICCL in ICIC */
+        if ((pd->iccl > 0xff) && (pd->flags & IIC_FLAG_HAS_ICIC67))
+                pd->icic |= ICIC_ICCLB8;
         else
-                pd->icch = (u_int8_t)(num/denom);
+                pd->icic &= ~ICIC_ICCLB8;
 
+        pd->icch = sh_mobile_i2c_icch(i2c_clk_khz, tHIGH, tf, offset);
         /* one more bit of ICCH in ICIC */
-        if (pd->flags & IIC_FLAG_HAS_ICIC67) {
-                if ((num/denom) > 0xff)
-                        pd->icic |= ICIC_ICCHB8;
-                else
-                        pd->icic &= ~ICIC_ICCHB8;
-        }
+        if ((pd->icch > 0xff) && (pd->flags & IIC_FLAG_HAS_ICIC67))
+                pd->icic |= ICIC_ICCHB8;
+        else
+                pd->icic &= ~ICIC_ICCHB8;
+
+out:
+        clk_disable(pd->clk);
+}
+
+static void activate_ch(struct sh_mobile_i2c_data *pd)
+{
+        /* Wake up device and enable clock */
+        pm_runtime_get_sync(pd->dev);
+        clk_enable(pd->clk);
 
         /* Enable channel and configure rx ack */
         iic_set_clr(pd, ICCR, ICCR_ICE, 0);
@@ -246,8 +281,8 @@ static void activate_ch(struct sh_mobile_i2c_data *pd)
         iic_wr(pd, ICIC, 0);
 
         /* Set the clock */
-        iic_wr(pd, ICCL, pd->iccl);
-        iic_wr(pd, ICCH, pd->icch);
+        iic_wr(pd, ICCL, pd->iccl & 0xff);
+        iic_wr(pd, ICCH, pd->icch & 0xff);
 }
 
 static void deactivate_ch(struct sh_mobile_i2c_data *pd)
@@ -434,6 +469,9 @@ static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id)
                 wake_up(&pd->wait);
         }
 
+        /* defeat write posting to avoid spurious WAIT interrupts */
+        iic_rd(pd, ICSR);
+
         return IRQ_HANDLED;
 }
 
@@ -451,8 +489,8 @@ static int start_ch(struct sh_mobile_i2c_data *pd, struct i2c_msg *usr_msg)
         iic_set_clr(pd, ICCR, ICCR_ICE, 0);
 
         /* Set the clock */
-        iic_wr(pd, ICCL, pd->iccl);
-        iic_wr(pd, ICCH, pd->icch);
+        iic_wr(pd, ICCL, pd->iccl & 0xff);
+        iic_wr(pd, ICCH, pd->icch & 0xff);
 
         pd->msg = usr_msg;
         pd->pos = -1;
@@ -621,10 +659,13 @@ static int sh_mobile_i2c_probe(struct platform_device *dev)
                 goto err_irq;
         }
 
-        /* Use platformd data bus speed or NORMAL_SPEED */
-        pd->bus_speed = NORMAL_SPEED;
+        /* Use platform data bus speed or STANDARD_MODE */
+        pd->bus_speed = STANDARD_MODE;
         if (pdata && pdata->bus_speed)
                 pd->bus_speed = pdata->bus_speed;
+        pd->clks_per_count = 1;
+        if (pdata && pdata->clks_per_count)
+                pd->clks_per_count = pdata->clks_per_count;
 
         /* The IIC blocks on SH-Mobile ARM processors
          * come with two new bits in ICIC.
@@ -632,6 +673,8 @@ static int sh_mobile_i2c_probe(struct platform_device *dev)
         if (size > 0x17)
                 pd->flags |= IIC_FLAG_HAS_ICIC67;
 
+        sh_mobile_i2c_init(pd);
+
         /* Enable Runtime PM for this device.
          *
          * Also tell the Runtime PM core to ignore children
@@ -667,8 +710,9 @@ static int sh_mobile_i2c_probe(struct platform_device *dev)
                 goto err_all;
         }
 
-        dev_info(&dev->dev, "I2C adapter %d with bus speed %lu Hz\n",
-                 adap->nr, pd->bus_speed);
+        dev_info(&dev->dev,
+                 "I2C adapter %d with bus speed %lu Hz (L/H=%x/%x)\n",
+                 adap->nr, pd->bus_speed, pd->iccl, pd->icch);
 
         of_i2c_register_devices(adap);
         return 0;
diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c
index 566a6757a33..3b7bc06fe8a 100644
--- a/drivers/i2c/muxes/i2c-mux-gpio.c
+++ b/drivers/i2c/muxes/i2c-mux-gpio.c
@@ -16,6 +16,8 @@
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/gpio.h>
+#include <linux/of_i2c.h>
+#include <linux/of_gpio.h>
 
 struct gpiomux {
         struct i2c_adapter *parent;
@@ -57,29 +59,110 @@ static int __devinit match_gpio_chip_by_label(struct gpio_chip *chip,
         return !strcmp(chip->label, data);
 }
 
+#ifdef CONFIG_OF
+static int __devinit i2c_mux_gpio_probe_dt(struct gpiomux *mux,
+                                        struct platform_device *pdev)
+{
+        struct device_node *np = pdev->dev.of_node;
+        struct device_node *adapter_np, *child;
+        struct i2c_adapter *adapter;
+        unsigned *values, *gpios;
+        int i = 0;
+
+        if (!np)
+                return -ENODEV;
+
+        adapter_np = of_parse_phandle(np, "i2c-parent", 0);
+        if (!adapter_np) {
+                dev_err(&pdev->dev, "Cannot parse i2c-parent\n");
+                return -ENODEV;
+        }
+        adapter = of_find_i2c_adapter_by_node(adapter_np);
+        if (!adapter) {
+                dev_err(&pdev->dev, "Cannot find parent bus\n");
+                return -ENODEV;
+        }
+        mux->data.parent = i2c_adapter_id(adapter);
+        put_device(&adapter->dev);
+
+        mux->data.n_values = of_get_child_count(np);
+
+        values = devm_kzalloc(&pdev->dev,
+                              sizeof(*mux->data.values) * mux->data.n_values,
+                              GFP_KERNEL);
+        if (!values) {
+                dev_err(&pdev->dev, "Cannot allocate values array");
+                return -ENOMEM;
+        }
+
+        for_each_child_of_node(np, child) {
+                of_property_read_u32(child, "reg", values + i);
+                i++;
+        }
+        mux->data.values = values;
+
+        if (of_property_read_u32(np, "idle-state", &mux->data.idle))
+                mux->data.idle = I2C_MUX_GPIO_NO_IDLE;
+
+        mux->data.n_gpios = of_gpio_named_count(np, "mux-gpios");
+        if (mux->data.n_gpios < 0) {
+                dev_err(&pdev->dev, "Missing mux-gpios property in the DT.\n");
+                return -EINVAL;
+        }
+
+        gpios = devm_kzalloc(&pdev->dev,
+                             sizeof(*mux->data.gpios) * mux->data.n_gpios, GFP_KERNEL);
+        if (!gpios) {
+                dev_err(&pdev->dev, "Cannot allocate gpios array");
+                return -ENOMEM;
+        }
+
+        for (i = 0; i < mux->data.n_gpios; i++)
+                gpios[i] = of_get_named_gpio(np, "mux-gpios", i);
+
+        mux->data.gpios = gpios;
+
+        return 0;
+}
+#else
+static int __devinit i2c_mux_gpio_probe_dt(struct gpiomux *mux,
+                                        struct platform_device *pdev)
+{
+        return 0;
+}
+#endif
+
 static int __devinit i2c_mux_gpio_probe(struct platform_device *pdev)
 {
         struct gpiomux *mux;
-        struct i2c_mux_gpio_platform_data *pdata;
         struct i2c_adapter *parent;
         int (*deselect) (struct i2c_adapter *, void *, u32);
         unsigned initial_state, gpio_base;
         int i, ret;
 
-        pdata = pdev->dev.platform_data;
-        if (!pdata) {
-                dev_err(&pdev->dev, "Missing platform data\n");
-                return -ENODEV;
+        mux = devm_kzalloc(&pdev->dev, sizeof(*mux), GFP_KERNEL);
+        if (!mux) {
+                dev_err(&pdev->dev, "Cannot allocate gpiomux structure");
+                return -ENOMEM;
         }
 
+        platform_set_drvdata(pdev, mux);
+
+        if (!pdev->dev.platform_data) {
+                ret = i2c_mux_gpio_probe_dt(mux, pdev);
+                if (ret < 0)
+                        return ret;
+        } else
+                memcpy(&mux->data, pdev->dev.platform_data, sizeof(mux->data));
+
         /*
          * If a GPIO chip name is provided, the GPIO pin numbers provided are
          * relative to its base GPIO number. Otherwise they are absolute.
          */
-        if (pdata->gpio_chip) {
+        if (mux->data.gpio_chip) {
                 struct gpio_chip *gpio;
 
-                gpio = gpiochip_find(pdata->gpio_chip,
+                gpio = gpiochip_find(mux->data.gpio_chip,
                                      match_gpio_chip_by_label);
                 if (!gpio)
                         return -EPROBE_DEFER;
@@ -89,49 +172,44 @@ static int __devinit i2c_mux_gpio_probe(struct platform_device *pdev)
                 gpio_base = 0;
         }
 
-        parent = i2c_get_adapter(pdata->parent);
+        parent = i2c_get_adapter(mux->data.parent);
         if (!parent) {
                 dev_err(&pdev->dev, "Parent adapter (%d) not found\n",
-                        pdata->parent);
+                        mux->data.parent);
                 return -ENODEV;
         }
 
-        mux = devm_kzalloc(&pdev->dev, sizeof(*mux), GFP_KERNEL);
-        if (!mux) {
-                ret = -ENOMEM;
-                goto alloc_failed;
-        }
-
         mux->parent = parent;
-        mux->data = *pdata;
         mux->gpio_base = gpio_base;
+
         mux->adap = devm_kzalloc(&pdev->dev,
-                                 sizeof(*mux->adap) * pdata->n_values,
+                                 sizeof(*mux->adap) * mux->data.n_values,
                                  GFP_KERNEL);
         if (!mux->adap) {
+                dev_err(&pdev->dev, "Cannot allocate i2c_adapter structure");
                 ret = -ENOMEM;
                 goto alloc_failed;
         }
 
-        if (pdata->idle != I2C_MUX_GPIO_NO_IDLE) {
-                initial_state = pdata->idle;
+        if (mux->data.idle != I2C_MUX_GPIO_NO_IDLE) {
+                initial_state = mux->data.idle;
                 deselect = i2c_mux_gpio_deselect;
         } else {
-                initial_state = pdata->values[0];
+                initial_state = mux->data.values[0];
                 deselect = NULL;
         }
 
-        for (i = 0; i < pdata->n_gpios; i++) {
-                ret = gpio_request(gpio_base + pdata->gpios[i], "i2c-mux-gpio");
+        for (i = 0; i < mux->data.n_gpios; i++) {
+                ret = gpio_request(gpio_base + mux->data.gpios[i], "i2c-mux-gpio");
                 if (ret)
                         goto err_request_gpio;
-                gpio_direction_output(gpio_base + pdata->gpios[i],
+                gpio_direction_output(gpio_base + mux->data.gpios[i],
                                       initial_state & (1 << i));
         }
 
-        for (i = 0; i < pdata->n_values; i++) {
-                u32 nr = pdata->base_nr ? (pdata->base_nr + i) : 0;
-                unsigned int class = pdata->classes ? pdata->classes[i] : 0;
+        for (i = 0; i < mux->data.n_values; i++) {
+                u32 nr = mux->data.base_nr ? (mux->data.base_nr + i) : 0;
+                unsigned int class = mux->data.classes ? mux->data.classes[i] : 0;
 
                 mux->adap[i] = i2c_add_mux_adapter(parent, &pdev->dev, mux, nr,
                                                    i, class,
@@ -144,19 +222,17 @@ static int __devinit i2c_mux_gpio_probe(struct platform_device *pdev)
         }
 
         dev_info(&pdev->dev, "%d port mux on %s adapter\n",
-                 pdata->n_values, parent->name);
-
-        platform_set_drvdata(pdev, mux);
+                 mux->data.n_values, parent->name);
 
         return 0;
 
 add_adapter_failed:
         for (; i > 0; i--)
                 i2c_del_mux_adapter(mux->adap[i - 1]);
-        i = pdata->n_gpios;
+        i = mux->data.n_gpios;
 err_request_gpio:
         for (; i > 0; i--)
-                gpio_free(gpio_base + pdata->gpios[i - 1]);
+                gpio_free(gpio_base + mux->data.gpios[i - 1]);
 alloc_failed:
         i2c_put_adapter(parent);
 
@@ -180,12 +256,19 @@ static int __devexit i2c_mux_gpio_remove(struct platform_device *pdev)
         return 0;
 }
 
+static const struct of_device_id i2c_mux_gpio_of_match[] __devinitconst = {
+        { .compatible = "i2c-mux-gpio", },
+        {},
+};
+MODULE_DEVICE_TABLE(of, i2c_mux_gpio_of_match);
+
 static struct platform_driver i2c_mux_gpio_driver = {
         .probe  = i2c_mux_gpio_probe,
         .remove = __devexit_p(i2c_mux_gpio_remove),
         .driver = {
                 .owner  = THIS_MODULE,
                 .name   = "i2c-mux-gpio",
+                .of_match_table = of_match_ptr(i2c_mux_gpio_of_match),
         },
 };
 
diff --git a/include/linux/i2c-omap.h b/include/linux/i2c-omap.h
index 92a0dc75bc7..babe0cf6d56 100644
--- a/include/linux/i2c-omap.h
+++ b/include/linux/i2c-omap.h
@@ -20,8 +20,6 @@
 #define OMAP_I2C_FLAG_NO_FIFO                   BIT(0)
 #define OMAP_I2C_FLAG_SIMPLE_CLOCK              BIT(1)
 #define OMAP_I2C_FLAG_16BIT_DATA_REG            BIT(2)
-#define OMAP_I2C_FLAG_RESET_REGS_POSTIDLE       BIT(3)
-#define OMAP_I2C_FLAG_APPLY_ERRATA_I207 BIT(4)
 #define OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK BIT(5)
 #define OMAP_I2C_FLAG_FORCE_19200_INT_CLK       BIT(6)
 /* how the CPU address bus must be translated for I2C unit access */
diff --git a/include/linux/i2c/i2c-sh_mobile.h b/include/linux/i2c/i2c-sh_mobile.h
index beda7081aea..06e3089795f 100644
--- a/include/linux/i2c/i2c-sh_mobile.h
+++ b/include/linux/i2c/i2c-sh_mobile.h
@@ -5,6 +5,7 @@
 
 struct i2c_sh_mobile_platform_data {
         unsigned long bus_speed;
+        unsigned int clks_per_count;
 };
 
 #endif /* __I2C_SH_MOBILE_H__ */
diff --git a/include/linux/platform_data/i2c-cbus-gpio.h b/include/linux/platform_data/i2c-cbus-gpio.h
new file mode 100644
index 00000000000..6faa992a950
--- /dev/null
+++ b/include/linux/platform_data/i2c-cbus-gpio.h
@@ -0,0 +1,27 @@
+/*
+ * i2c-cbus-gpio.h - CBUS I2C platform_data definition
+ *
+ * Copyright (C) 2004-2009 Nokia Corporation
+ *
+ * Written by Felipe Balbi and Aaro Koskinen.
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __INCLUDE_LINUX_I2C_CBUS_GPIO_H
+#define __INCLUDE_LINUX_I2C_CBUS_GPIO_H
+
+struct i2c_cbus_platform_data {
+        int dat_gpio;
+        int clk_gpio;
+        int sel_gpio;
+};
+
+#endif /* __INCLUDE_LINUX_I2C_CBUS_GPIO_H */