12 files changed, 490 insertions, 412 deletions

diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
index 3e3b680dc007..b51a402752c4 100644
--- a/drivers/i2c/Kconfig
+++ b/drivers/i2c/Kconfig
@@ -23,17 +23,14 @@ config I2C
           This I2C support can also be built as a module.  If so, the module
           will be called i2c-core.
 
-config I2C_ACPI
-        bool "I2C ACPI support"
-        select I2C
-        depends on ACPI
+config ACPI_I2C_OPREGION
+        bool "ACPI I2C Operation region support"
+        depends on I2C=y && ACPI
         default y
         help
-          Say Y here if you want to enable ACPI I2C support. This includes support
-          for automatic enumeration of I2C slave devices and support for ACPI I2C
-          Operation Regions. Operation Regions allow firmware (BIOS) code to
-          access I2C slave devices, such as smart batteries through an I2C host
-          controller driver.
+          Say Y here if you want to enable ACPI I2C operation region support.
+          Operation Regions allow firmware (BIOS) code to access I2C slave devices,
+          such as smart batteries through an I2C host controller driver.
 
 if I2C
 
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index a1f590cbb435..1722f50f2473 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -2,11 +2,8 @@
 # Makefile for the i2c core.
 #
 
-i2ccore-y := i2c-core.o
-i2ccore-$(CONFIG_I2C_ACPI)      += i2c-acpi.o
-
 obj-$(CONFIG_I2C_BOARDINFO)     += i2c-boardinfo.o
-obj-$(CONFIG_I2C)               += i2ccore.o
+obj-$(CONFIG_I2C)               += i2c-core.o
 obj-$(CONFIG_I2C_SMBUS)         += i2c-smbus.o
 obj-$(CONFIG_I2C_CHARDEV)       += i2c-dev.o
 obj-$(CONFIG_I2C_MUX)           += i2c-mux.o
diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
index 79a68999a696..917d54588d95 100644
--- a/drivers/i2c/busses/i2c-at91.c
+++ b/drivers/i2c/busses/i2c-at91.c
@@ -101,6 +101,7 @@ struct at91_twi_dev {
         unsigned twi_cwgr_reg;
         struct at91_twi_pdata *pdata;
         bool use_dma;
+        bool recv_len_abort;
         struct at91_twi_dma dma;
 };
 
@@ -267,12 +268,24 @@ static void at91_twi_read_next_byte(struct at91_twi_dev *dev)
         *dev->buf = at91_twi_read(dev, AT91_TWI_RHR) & 0xff;
         --dev->buf_len;
 
+        /* return if aborting, we only needed to read RHR to clear RXRDY*/
+        if (dev->recv_len_abort)
+                return;
+
         /* handle I2C_SMBUS_BLOCK_DATA */
         if (unlikely(dev->msg->flags & I2C_M_RECV_LEN)) {
-                dev->msg->flags &= ~I2C_M_RECV_LEN;
-                dev->buf_len += *dev->buf;
-                dev->msg->len = dev->buf_len + 1;
-                dev_dbg(dev->dev, "received block length %d\n", dev->buf_len);
+                /* ensure length byte is a valid value */
+                if (*dev->buf <= I2C_SMBUS_BLOCK_MAX && *dev->buf > 0) {
+                        dev->msg->flags &= ~I2C_M_RECV_LEN;
+                        dev->buf_len += *dev->buf;
+                        dev->msg->len = dev->buf_len + 1;
+                        dev_dbg(dev->dev, "received block length %d\n",
+                                         dev->buf_len);
+                } else {
+                        /* abort and send the stop by reading one more byte */
+                        dev->recv_len_abort = true;
+                        dev->buf_len = 1;
+                }
         }
 
         /* send stop if second but last byte has been read */
@@ -421,8 +434,8 @@ static int at91_do_twi_transfer(struct at91_twi_dev *dev)
                 }
         }
 
-        ret = wait_for_completion_interruptible_timeout(&dev->cmd_complete,
-                                                        dev->adapter.timeout);
+        ret = wait_for_completion_io_timeout(&dev->cmd_complete,
+                                             dev->adapter.timeout);
         if (ret == 0) {
                 dev_err(dev->dev, "controller timed out\n");
                 at91_init_twi_bus(dev);
@@ -444,6 +457,12 @@ static int at91_do_twi_transfer(struct at91_twi_dev *dev)
                 ret = -EIO;
                 goto error;
         }
+        if (dev->recv_len_abort) {
+                dev_err(dev->dev, "invalid smbus block length recvd\n");
+                ret = -EPROTO;
+                goto error;
+        }
+
         dev_dbg(dev->dev, "transfer complete\n");
 
         return 0;
@@ -500,6 +519,7 @@ static int at91_twi_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, int num)
         dev->buf_len = m_start->len;
         dev->buf = m_start->buf;
         dev->msg = m_start;
+        dev->recv_len_abort = false;
 
         ret = at91_do_twi_transfer(dev);
 
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index 2994690b26e9..10467a327749 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -164,6 +164,7 @@
 
 /* Older devices have their ID defined in <linux/pci_ids.h> */
 #define PCI_DEVICE_ID_INTEL_BAYTRAIL_SMBUS              0x0f12
+#define PCI_DEVICE_ID_INTEL_BRASWELL_SMBUS              0x2292
 #define PCI_DEVICE_ID_INTEL_COUGARPOINT_SMBUS           0x1c22
 #define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS              0x1d22
 /* Patsburg also has three 'Integrated Device Function' SMBus controllers */
@@ -828,6 +829,7 @@ static const struct pci_device_id i801_ids[] = {
         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WILDCATPOINT_SMBUS) },
         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WILDCATPOINT_LP_SMBUS) },
         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_BAYTRAIL_SMBUS) },
+        { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_BRASWELL_SMBUS) },
         { 0, }
 };
 
diff --git a/drivers/i2c/busses/i2c-ismt.c b/drivers/i2c/busses/i2c-ismt.c
index 984492553e95..d9ee43c80cde 100644
--- a/drivers/i2c/busses/i2c-ismt.c
+++ b/drivers/i2c/busses/i2c-ismt.c
@@ -497,7 +497,7 @@ static int ismt_access(struct i2c_adapter *adap, u16 addr,
                         desc->wr_len_cmd = dma_size;
                         desc->control |= ISMT_DESC_BLK;
                         priv->dma_buffer[0] = command;
-                        memcpy(&priv->dma_buffer[1], &data->block[1], dma_size);
+                        memcpy(&priv->dma_buffer[1], &data->block[1], dma_size - 1);
                 } else {
                         /* Block Read */
                         dev_dbg(dev, "I2C_SMBUS_BLOCK_DATA:  READ\n");
@@ -525,7 +525,7 @@ static int ismt_access(struct i2c_adapter *adap, u16 addr,
                         desc->wr_len_cmd = dma_size;
                         desc->control |= ISMT_DESC_I2C;
                         priv->dma_buffer[0] = command;
-                        memcpy(&priv->dma_buffer[1], &data->block[1], dma_size);
+                        memcpy(&priv->dma_buffer[1], &data->block[1], dma_size - 1);
                 } else {
                         /* i2c Block Read */
                         dev_dbg(dev, "I2C_SMBUS_I2C_BLOCK_DATA:  READ\n");
diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c
index 6dc5ded86f62..2f64273d3f2b 100644
--- a/drivers/i2c/busses/i2c-mv64xxx.c
+++ b/drivers/i2c/busses/i2c-mv64xxx.c
@@ -746,8 +746,7 @@ mv64xxx_of_config(struct mv64xxx_i2c_data *drv_data,
         }
         tclk = clk_get_rate(drv_data->clk);
 
-        rc = of_property_read_u32(np, "clock-frequency", &bus_freq);
-        if (rc)
+        if (of_property_read_u32(np, "clock-frequency", &bus_freq))
                 bus_freq = 100000; /* 100kHz by default */
 
         if (!mv64xxx_find_baud_factors(bus_freq, tclk,
diff --git a/drivers/i2c/busses/i2c-mxs.c b/drivers/i2c/busses/i2c-mxs.c
index 7170fc892829..65a21fed08b5 100644
--- a/drivers/i2c/busses/i2c-mxs.c
+++ b/drivers/i2c/busses/i2c-mxs.c
@@ -429,7 +429,7 @@ static int mxs_i2c_pio_setup_xfer(struct i2c_adapter *adap,
                 ret = mxs_i2c_pio_wait_xfer_end(i2c);
                 if (ret) {
                         dev_err(i2c->dev,
-                                "PIO: Failed to send SELECT command!\n");
+                                "PIO: Failed to send READ command!\n");
                         goto cleanup;
                 }
 
diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c
index f3c7139dfa25..e506fcd3ca04 100644
--- a/drivers/i2c/busses/i2c-rcar.c
+++ b/drivers/i2c/busses/i2c-rcar.c
@@ -34,6 +34,7 @@
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/slab.h>
+#include <linux/spinlock.h>
 
 /* register offsets */
 #define ICSCR   0x00    /* slave ctrl */
@@ -75,8 +76,8 @@
 #define RCAR_IRQ_RECV   (MNR | MAL | MST | MAT | MDR)
 #define RCAR_IRQ_STOP   (MST)
 
-#define RCAR_IRQ_ACK_SEND       (~(MAT | MDE))
-#define RCAR_IRQ_ACK_RECV       (~(MAT | MDR))
+#define RCAR_IRQ_ACK_SEND       (~(MAT | MDE) & 0xFF)
+#define RCAR_IRQ_ACK_RECV       (~(MAT | MDR) & 0xFF)
 
 #define ID_LAST_MSG     (1 << 0)
 #define ID_IOERROR      (1 << 1)
@@ -95,6 +96,7 @@ struct rcar_i2c_priv {
         struct i2c_msg  *msg;
         struct clk *clk;
 
+        spinlock_t lock;
         wait_queue_head_t wait;
 
         int pos;
@@ -365,20 +367,20 @@ static irqreturn_t rcar_i2c_irq(int irq, void *ptr)
         struct rcar_i2c_priv *priv = ptr;
         u32 msr;
 
+        /*-------------- spin lock -----------------*/
+        spin_lock(&priv->lock);
+
         msr = rcar_i2c_read(priv, ICMSR);
 
+        /* Only handle interrupts that are currently enabled */
+        msr &= rcar_i2c_read(priv, ICMIER);
+
         /* Arbitration lost */
         if (msr & MAL) {
                 rcar_i2c_flags_set(priv, (ID_DONE | ID_ARBLOST));
                 goto out;
         }
 
-        /* Stop */
-        if (msr & MST) {
-                rcar_i2c_flags_set(priv, ID_DONE);
-                goto out;
-        }
-
         /* Nack */
         if (msr & MNR) {
                 /* go to stop phase */
@@ -388,6 +390,12 @@ static irqreturn_t rcar_i2c_irq(int irq, void *ptr)
                 goto out;
         }
 
+        /* Stop */
+        if (msr & MST) {
+                rcar_i2c_flags_set(priv, ID_DONE);
+                goto out;
+        }
+
         if (rcar_i2c_is_recv(priv))
                 rcar_i2c_flags_set(priv, rcar_i2c_irq_recv(priv, msr));
         else
@@ -400,6 +408,9 @@ out:
                 wake_up(&priv->wait);
         }
 
+        spin_unlock(&priv->lock);
+        /*-------------- spin unlock -----------------*/
+
         return IRQ_HANDLED;
 }
 
@@ -409,14 +420,21 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
 {
         struct rcar_i2c_priv *priv = i2c_get_adapdata(adap);
         struct device *dev = rcar_i2c_priv_to_dev(priv);
+        unsigned long flags;
         int i, ret, timeout;
 
         pm_runtime_get_sync(dev);
 
+        /*-------------- spin lock -----------------*/
+        spin_lock_irqsave(&priv->lock, flags);
+
         rcar_i2c_init(priv);
         /* start clock */
         rcar_i2c_write(priv, ICCCR, priv->icccr);
 
+        spin_unlock_irqrestore(&priv->lock, flags);
+        /*-------------- spin unlock -----------------*/
+
         ret = rcar_i2c_bus_barrier(priv);
         if (ret < 0)
                 goto out;
@@ -428,6 +446,9 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
                         break;
                 }
 
+                /*-------------- spin lock -----------------*/
+                spin_lock_irqsave(&priv->lock, flags);
+
                 /* init each data */
                 priv->msg       = &msgs[i];
                 priv->pos       = 0;
@@ -437,6 +458,9 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
 
                 ret = rcar_i2c_prepare_msg(priv);
 
+                spin_unlock_irqrestore(&priv->lock, flags);
+                /*-------------- spin unlock -----------------*/
+
                 if (ret < 0)
                         break;
 
@@ -540,6 +564,7 @@ static int rcar_i2c_probe(struct platform_device *pdev)
 
         irq = platform_get_irq(pdev, 0);
         init_waitqueue_head(&priv->wait);
+        spin_lock_init(&priv->lock);
 
         adap = &priv->adap;
         adap->nr = pdev->id;
diff --git a/drivers/i2c/busses/i2c-rk3x.c b/drivers/i2c/busses/i2c-rk3x.c
index 69e11853e8bf..93cfc837200b 100644
--- a/drivers/i2c/busses/i2c-rk3x.c
+++ b/drivers/i2c/busses/i2c-rk3x.c
@@ -323,6 +323,10 @@ static void rk3x_i2c_handle_read(struct rk3x_i2c *i2c, unsigned int ipd)
         /* ack interrupt */
         i2c_writel(i2c, REG_INT_MBRF, REG_IPD);
 
+        /* Can only handle a maximum of 32 bytes at a time */
+        if (len > 32)
+                len = 32;
+
         /* read the data from receive buffer */
         for (i = 0; i < len; ++i) {
                 if (i % 4 == 0)
@@ -429,12 +433,11 @@ static void rk3x_i2c_set_scl_rate(struct rk3x_i2c *i2c, unsigned long scl_rate)
         unsigned long i2c_rate = clk_get_rate(i2c->clk);
         unsigned int div;
 
-        /* SCL rate = (clk rate) / (8 * DIV) */
-        div = DIV_ROUND_UP(i2c_rate, scl_rate * 8);
-
-        /* The lower and upper half of the CLKDIV reg describe the length of
-         * SCL low & high periods. */
-        div = DIV_ROUND_UP(div, 2);
+        /* set DIV = DIVH = DIVL
+         * SCL rate = (clk rate) / (8 * (DIVH + 1 + DIVL + 1))
+         *          = (clk rate) / (16 * (DIV + 1))
+         */
+        div = DIV_ROUND_UP(i2c_rate, scl_rate * 16) - 1;
 
         i2c_writel(i2c, (div << 16) | (div & 0xffff), REG_CLKDIV);
 }
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 87d0371cebb7..efba1ebe16ba 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -380,34 +380,33 @@ static inline int tegra_i2c_clock_enable(struct tegra_i2c_dev *i2c_dev)
 {
         int ret;
         if (!i2c_dev->hw->has_single_clk_source) {
-                ret = clk_prepare_enable(i2c_dev->fast_clk);
+                ret = clk_enable(i2c_dev->fast_clk);
                 if (ret < 0) {
                         dev_err(i2c_dev->dev,
                                 "Enabling fast clk failed, err %d\n", ret);
                         return ret;
                 }
         }
-        ret = clk_prepare_enable(i2c_dev->div_clk);
+        ret = clk_enable(i2c_dev->div_clk);
         if (ret < 0) {
                 dev_err(i2c_dev->dev,
                         "Enabling div clk failed, err %d\n", ret);
-                clk_disable_unprepare(i2c_dev->fast_clk);
+                clk_disable(i2c_dev->fast_clk);
         }
         return ret;
 }
 
 static inline void tegra_i2c_clock_disable(struct tegra_i2c_dev *i2c_dev)
 {
-        clk_disable_unprepare(i2c_dev->div_clk);
+        clk_disable(i2c_dev->div_clk);
         if (!i2c_dev->hw->has_single_clk_source)
-                clk_disable_unprepare(i2c_dev->fast_clk);
+                clk_disable(i2c_dev->fast_clk);
 }
 
 static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev)
 {
         u32 val;
         int err = 0;
-        int clk_multiplier = I2C_CLK_MULTIPLIER_STD_FAST_MODE;
         u32 clk_divisor;
 
         err = tegra_i2c_clock_enable(i2c_dev);
@@ -428,9 +427,6 @@ static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev)
         i2c_writel(i2c_dev, val, I2C_CNFG);
         i2c_writel(i2c_dev, 0, I2C_INT_MASK);
 
-        clk_multiplier *= (i2c_dev->hw->clk_divisor_std_fast_mode + 1);
-        clk_set_rate(i2c_dev->div_clk, i2c_dev->bus_clk_rate * clk_multiplier);
-
         /* Make sure clock divisor programmed correctly */
         clk_divisor = i2c_dev->hw->clk_divisor_hs_mode;
         clk_divisor |= i2c_dev->hw->clk_divisor_std_fast_mode <<
@@ -712,6 +708,7 @@ static int tegra_i2c_probe(struct platform_device *pdev)
         void __iomem *base;
         int irq;
         int ret = 0;
+        int clk_multiplier = I2C_CLK_MULTIPLIER_STD_FAST_MODE;
 
         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
         base = devm_ioremap_resource(&pdev->dev, res);
@@ -777,17 +774,39 @@ static int tegra_i2c_probe(struct platform_device *pdev)
 
         platform_set_drvdata(pdev, i2c_dev);
 
+        if (!i2c_dev->hw->has_single_clk_source) {
+                ret = clk_prepare(i2c_dev->fast_clk);
+                if (ret < 0) {
+                        dev_err(i2c_dev->dev, "Clock prepare failed %d\n", ret);
+                        return ret;
+                }
+        }
+
+        clk_multiplier *= (i2c_dev->hw->clk_divisor_std_fast_mode + 1);
+        ret = clk_set_rate(i2c_dev->div_clk,
+                           i2c_dev->bus_clk_rate * clk_multiplier);
+        if (ret) {
+                dev_err(i2c_dev->dev, "Clock rate change failed %d\n", ret);
+                goto unprepare_fast_clk;
+        }
+
+        ret = clk_prepare(i2c_dev->div_clk);
+        if (ret < 0) {
+                dev_err(i2c_dev->dev, "Clock prepare failed %d\n", ret);
+                goto unprepare_fast_clk;
+        }
+
         ret = tegra_i2c_init(i2c_dev);
         if (ret) {
                 dev_err(&pdev->dev, "Failed to initialize i2c controller");
-                return ret;
+                goto unprepare_div_clk;
         }
 
         ret = devm_request_irq(&pdev->dev, i2c_dev->irq,
                         tegra_i2c_isr, 0, dev_name(&pdev->dev), i2c_dev);
         if (ret) {
                 dev_err(&pdev->dev, "Failed to request irq %i\n", i2c_dev->irq);
-                return ret;
+                goto unprepare_div_clk;
         }
 
         i2c_set_adapdata(&i2c_dev->adapter, i2c_dev);
@@ -803,16 +822,30 @@ static int tegra_i2c_probe(struct platform_device *pdev)
         ret = i2c_add_numbered_adapter(&i2c_dev->adapter);
         if (ret) {
                 dev_err(&pdev->dev, "Failed to add I2C adapter\n");
-                return ret;
+                goto unprepare_div_clk;
         }
 
         return 0;
+
+unprepare_div_clk:
+        clk_unprepare(i2c_dev->div_clk);
+
+unprepare_fast_clk:
+        if (!i2c_dev->hw->has_single_clk_source)
+                clk_unprepare(i2c_dev->fast_clk);
+
+        return ret;
 }
 
 static int tegra_i2c_remove(struct platform_device *pdev)
 {
         struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
         i2c_del_adapter(&i2c_dev->adapter);
+
+        clk_unprepare(i2c_dev->div_clk);
+        if (!i2c_dev->hw->has_single_clk_source)
+                clk_unprepare(i2c_dev->fast_clk);
+
         return 0;
 }
 
diff --git a/drivers/i2c/i2c-acpi.c b/drivers/i2c/i2c-acpi.c
deleted file mode 100644
index e8b61967334b..000000000000
--- a/drivers/i2c/i2c-acpi.c
+++ /dev/null
@@ -1,362 +0,0 @@
-/*
- * I2C ACPI code
- *
- * Copyright (C) 2014 Intel Corp
- *
- * Author: Lan Tianyu <tianyu.lan@intel.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * 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.
- */
-#define pr_fmt(fmt) "I2C/ACPI : " fmt
-
-#include <linux/kernel.h>
-#include <linux/errno.h>
-#include <linux/err.h>
-#include <linux/i2c.h>
-#include <linux/acpi.h>
-
-struct acpi_i2c_handler_data {
-        struct acpi_connection_info info;
-        struct i2c_adapter *adapter;
-};
-
-struct gsb_buffer {
-        u8      status;
-        u8      len;
-        union {
-                u16     wdata;
-                u8      bdata;
-                u8      data[0];
-        };
-} __packed;
-
-static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data)
-{
-        struct i2c_board_info *info = data;
-
-        if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
-                struct acpi_resource_i2c_serialbus *sb;
-
-                sb = &ares->data.i2c_serial_bus;
-                if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) {
-                        info->addr = sb->slave_address;
-                        if (sb->access_mode == ACPI_I2C_10BIT_MODE)
-                                info->flags |= I2C_CLIENT_TEN;
-                }
-        } else if (info->irq < 0) {
-                struct resource r;
-
-                if (acpi_dev_resource_interrupt(ares, 0, &r))
-                        info->irq = r.start;
-        }
-
-        /* Tell the ACPI core to skip this resource */
-        return 1;
-}
-
-static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
-                                       void *data, void **return_value)
-{
-        struct i2c_adapter *adapter = data;
-        struct list_head resource_list;
-        struct i2c_board_info info;
-        struct acpi_device *adev;
-        int ret;
-
-        if (acpi_bus_get_device(handle, &adev))
-                return AE_OK;
-        if (acpi_bus_get_status(adev) || !adev->status.present)
-                return AE_OK;
-
-        memset(&info, 0, sizeof(info));
-        info.acpi_node.companion = adev;
-        info.irq = -1;
-
-        INIT_LIST_HEAD(&resource_list);
-        ret = acpi_dev_get_resources(adev, &resource_list,
-                                     acpi_i2c_add_resource, &info);
-        acpi_dev_free_resource_list(&resource_list);
-
-        if (ret < 0 || !info.addr)
-                return AE_OK;
-
-        adev->power.flags.ignore_parent = true;
-        strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type));
-        if (!i2c_new_device(adapter, &info)) {
-                adev->power.flags.ignore_parent = false;
-                dev_err(&adapter->dev,
-                        "failed to add I2C device %s from ACPI\n",
-                        dev_name(&adev->dev));
-        }
-
-        return AE_OK;
-}
-
-/**
- * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter
- * @adap: pointer to adapter
- *
- * Enumerate all I2C slave devices behind this adapter by walking the ACPI
- * namespace. When a device is found it will be added to the Linux device
- * model and bound to the corresponding ACPI handle.
- */
-void acpi_i2c_register_devices(struct i2c_adapter *adap)
-{
-        acpi_handle handle;
-        acpi_status status;
-
-        if (!adap->dev.parent)
-                return;
-
-        handle = ACPI_HANDLE(adap->dev.parent);
-        if (!handle)
-                return;
-
-        status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
-                                     acpi_i2c_add_device, NULL,
-                                     adap, NULL);
-        if (ACPI_FAILURE(status))
-                dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
-}
-
-static int acpi_gsb_i2c_read_bytes(struct i2c_client *client,
-                u8 cmd, u8 *data, u8 data_len)
-{
-
-        struct i2c_msg msgs[2];
-        int ret;
-        u8 *buffer;
-
-        buffer = kzalloc(data_len, GFP_KERNEL);
-        if (!buffer)
-                return AE_NO_MEMORY;
-
-        msgs[0].addr = client->addr;
-        msgs[0].flags = client->flags;
-        msgs[0].len = 1;
-        msgs[0].buf = &cmd;
-
-        msgs[1].addr = client->addr;
-        msgs[1].flags = client->flags | I2C_M_RD;
-        msgs[1].len = data_len;
-        msgs[1].buf = buffer;
-
-        ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
-        if (ret < 0)
-                dev_err(&client->adapter->dev, "i2c read failed\n");
-        else
-                memcpy(data, buffer, data_len);
-
-        kfree(buffer);
-        return ret;
-}
-
-static int acpi_gsb_i2c_write_bytes(struct i2c_client *client,
-                u8 cmd, u8 *data, u8 data_len)
-{
-
-        struct i2c_msg msgs[1];
-        u8 *buffer;
-        int ret = AE_OK;
-
-        buffer = kzalloc(data_len + 1, GFP_KERNEL);
-        if (!buffer)
-                return AE_NO_MEMORY;
-
-        buffer[0] = cmd;
-        memcpy(buffer + 1, data, data_len);
-
-        msgs[0].addr = client->addr;
-        msgs[0].flags = client->flags;
-        msgs[0].len = data_len + 1;
-        msgs[0].buf = buffer;
-
-        ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
-        if (ret < 0)
-                dev_err(&client->adapter->dev, "i2c write failed\n");
-
-        kfree(buffer);
-        return ret;
-}
-
-static acpi_status
-acpi_i2c_space_handler(u32 function, acpi_physical_address command,
-                        u32 bits, u64 *value64,
-                        void *handler_context, void *region_context)
-{
-        struct gsb_buffer *gsb = (struct gsb_buffer *)value64;
-        struct acpi_i2c_handler_data *data = handler_context;
-        struct acpi_connection_info *info = &data->info;
-        struct acpi_resource_i2c_serialbus *sb;
-        struct i2c_adapter *adapter = data->adapter;
-        struct i2c_client client;
-        struct acpi_resource *ares;
-        u32 accessor_type = function >> 16;
-        u8 action = function & ACPI_IO_MASK;
-        acpi_status ret = AE_OK;
-        int status;
-
-        ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
-        if (ACPI_FAILURE(ret))
-                return ret;
-
-        if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) {
-                ret = AE_BAD_PARAMETER;
-                goto err;
-        }
-
-        sb = &ares->data.i2c_serial_bus;
-        if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) {
-                ret = AE_BAD_PARAMETER;
-                goto err;
-        }
-
-        memset(&client, 0, sizeof(client));
-        client.adapter = adapter;
-        client.addr = sb->slave_address;
-        client.flags = 0;
-
-        if (sb->access_mode == ACPI_I2C_10BIT_MODE)
-                client.flags |= I2C_CLIENT_TEN;
-
-        switch (accessor_type) {
-        case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV:
-                if (action == ACPI_READ) {
-                        status = i2c_smbus_read_byte(&client);
-                        if (status >= 0) {
-                                gsb->bdata = status;
-                                status = 0;
-                        }
-                } else {
-                        status = i2c_smbus_write_byte(&client, gsb->bdata);
-                }
-                break;
-
-        case ACPI_GSB_ACCESS_ATTRIB_BYTE:
-                if (action == ACPI_READ) {
-                        status = i2c_smbus_read_byte_data(&client, command);
-                        if (status >= 0) {
-                                gsb->bdata = status;
-                                status = 0;
-                        }
-                } else {
-                        status = i2c_smbus_write_byte_data(&client, command,
-                                        gsb->bdata);
-                }
-                break;
-
-        case ACPI_GSB_ACCESS_ATTRIB_WORD:
-                if (action == ACPI_READ) {
-                        status = i2c_smbus_read_word_data(&client, command);
-                        if (status >= 0) {
-                                gsb->wdata = status;
-                                status = 0;
-                        }
-                } else {
-                        status = i2c_smbus_write_word_data(&client, command,
-                                        gsb->wdata);
-                }
-                break;
-
-        case ACPI_GSB_ACCESS_ATTRIB_BLOCK:
-                if (action == ACPI_READ) {
-                        status = i2c_smbus_read_block_data(&client, command,
-                                        gsb->data);
-                        if (status >= 0) {
-                                gsb->len = status;
-                                status = 0;
-                        }
-                } else {
-                        status = i2c_smbus_write_block_data(&client, command,
-                                        gsb->len, gsb->data);
-                }
-                break;
-
-        case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE:
-                if (action == ACPI_READ) {
-                        status = acpi_gsb_i2c_read_bytes(&client, command,
-                                        gsb->data, info->access_length);
-                        if (status > 0)
-                                status = 0;
-                } else {
-                        status = acpi_gsb_i2c_write_bytes(&client, command,
-                                        gsb->data, info->access_length);
-                }
-                break;
-
-        default:
-                pr_info("protocol(0x%02x) is not supported.\n", accessor_type);
-                ret = AE_BAD_PARAMETER;
-                goto err;
-        }
-
-        gsb->status = status;
-
- err:
-        ACPI_FREE(ares);
-        return ret;
-}
-
-
-int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)
-{
-        acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
-        struct acpi_i2c_handler_data *data;
-        acpi_status status;
-
-        if (!handle)
-                return -ENODEV;
-
-        data = kzalloc(sizeof(struct acpi_i2c_handler_data),
-                            GFP_KERNEL);
-        if (!data)
-                return -ENOMEM;
-
-        data->adapter = adapter;
-        status = acpi_bus_attach_private_data(handle, (void *)data);
-        if (ACPI_FAILURE(status)) {
-                kfree(data);
-                return -ENOMEM;
-        }
-
-        status = acpi_install_address_space_handler(handle,
-                                ACPI_ADR_SPACE_GSBUS,
-                                &acpi_i2c_space_handler,
-                                NULL,
-                                data);
-        if (ACPI_FAILURE(status)) {
-                dev_err(&adapter->dev, "Error installing i2c space handler\n");
-                acpi_bus_detach_private_data(handle);
-                kfree(data);
-                return -ENOMEM;
-        }
-
-        return 0;
-}
-
-void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)
-{
-        acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
-        struct acpi_i2c_handler_data *data;
-        acpi_status status;
-
-        if (!handle)
-                return;
-
-        acpi_remove_address_space_handler(handle,
-                                ACPI_ADR_SPACE_GSBUS,
-                                &acpi_i2c_space_handler);
-
-        status = acpi_bus_get_private_data(handle, (void **)&data);
-        if (ACPI_SUCCESS(status))
-                kfree(data);
-
-        acpi_bus_detach_private_data(handle);
-}
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 632057a44615..ccfbbab82a15 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -27,6 +27,8 @@
    OF support is copyright (c) 2008 Jochen Friedrich <jochen@scram.de>
    (based on a previous patch from Jon Smirl <jonsmirl@gmail.com>) and
    (c) 2013  Wolfram Sang <wsa@the-dreams.de>
+   I2C ACPI code Copyright (C) 2014 Intel Corp
+   Author: Lan Tianyu <tianyu.lan@intel.com>
  */
 
 #include <linux/module.h>
@@ -78,6 +80,368 @@ void i2c_transfer_trace_unreg(void)
         static_key_slow_dec(&i2c_trace_msg);
 }
 
+#if defined(CONFIG_ACPI)
+struct acpi_i2c_handler_data {
+        struct acpi_connection_info info;
+        struct i2c_adapter *adapter;
+};
+
+struct gsb_buffer {
+        u8      status;
+        u8      len;
+        union {
+                u16     wdata;
+                u8      bdata;
+                u8      data[0];
+        };
+} __packed;
+
+static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data)
+{
+        struct i2c_board_info *info = data;
+
+        if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
+                struct acpi_resource_i2c_serialbus *sb;
+
+                sb = &ares->data.i2c_serial_bus;
+                if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) {
+                        info->addr = sb->slave_address;
+                        if (sb->access_mode == ACPI_I2C_10BIT_MODE)
+                                info->flags |= I2C_CLIENT_TEN;
+                }
+        } else if (info->irq < 0) {
+                struct resource r;
+
+                if (acpi_dev_resource_interrupt(ares, 0, &r))
+                        info->irq = r.start;
+        }
+
+        /* Tell the ACPI core to skip this resource */
+        return 1;
+}
+
+static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
+                                       void *data, void **return_value)
+{
+        struct i2c_adapter *adapter = data;
+        struct list_head resource_list;
+        struct i2c_board_info info;
+        struct acpi_device *adev;
+        int ret;
+
+        if (acpi_bus_get_device(handle, &adev))
+                return AE_OK;
+        if (acpi_bus_get_status(adev) || !adev->status.present)
+                return AE_OK;
+
+        memset(&info, 0, sizeof(info));
+        info.acpi_node.companion = adev;
+        info.irq = -1;
+
+        INIT_LIST_HEAD(&resource_list);
+        ret = acpi_dev_get_resources(adev, &resource_list,
+                                     acpi_i2c_add_resource, &info);
+        acpi_dev_free_resource_list(&resource_list);
+
+        if (ret < 0 || !info.addr)
+                return AE_OK;
+
+        adev->power.flags.ignore_parent = true;
+        strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type));
+        if (!i2c_new_device(adapter, &info)) {
+                adev->power.flags.ignore_parent = false;
+                dev_err(&adapter->dev,
+                        "failed to add I2C device %s from ACPI\n",
+                        dev_name(&adev->dev));
+        }
+
+        return AE_OK;
+}
+
+/**
+ * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter
+ * @adap: pointer to adapter
+ *
+ * Enumerate all I2C slave devices behind this adapter by walking the ACPI
+ * namespace. When a device is found it will be added to the Linux device
+ * model and bound to the corresponding ACPI handle.
+ */
+static void acpi_i2c_register_devices(struct i2c_adapter *adap)
+{
+        acpi_handle handle;
+        acpi_status status;
+
+        if (!adap->dev.parent)
+                return;
+
+        handle = ACPI_HANDLE(adap->dev.parent);
+        if (!handle)
+                return;
+
+        status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
+                                     acpi_i2c_add_device, NULL,
+                                     adap, NULL);
+        if (ACPI_FAILURE(status))
+                dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
+}
+
+#else /* CONFIG_ACPI */
+static inline void acpi_i2c_register_devices(struct i2c_adapter *adap) { }
+#endif /* CONFIG_ACPI */
+
+#ifdef CONFIG_ACPI_I2C_OPREGION
+static int acpi_gsb_i2c_read_bytes(struct i2c_client *client,
+                u8 cmd, u8 *data, u8 data_len)
+{
+
+        struct i2c_msg msgs[2];
+        int ret;
+        u8 *buffer;
+
+        buffer = kzalloc(data_len, GFP_KERNEL);
+        if (!buffer)
+                return AE_NO_MEMORY;
+
+        msgs[0].addr = client->addr;
+        msgs[0].flags = client->flags;
+        msgs[0].len = 1;
+        msgs[0].buf = &cmd;
+
+        msgs[1].addr = client->addr;
+        msgs[1].flags = client->flags | I2C_M_RD;
+        msgs[1].len = data_len;
+        msgs[1].buf = buffer;
+
+        ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+        if (ret < 0)
+                dev_err(&client->adapter->dev, "i2c read failed\n");
+        else
+                memcpy(data, buffer, data_len);
+
+        kfree(buffer);
+        return ret;
+}
+
+static int acpi_gsb_i2c_write_bytes(struct i2c_client *client,
+                u8 cmd, u8 *data, u8 data_len)
+{
+
+        struct i2c_msg msgs[1];
+        u8 *buffer;
+        int ret = AE_OK;
+
+        buffer = kzalloc(data_len + 1, GFP_KERNEL);
+        if (!buffer)
+                return AE_NO_MEMORY;
+
+        buffer[0] = cmd;
+        memcpy(buffer + 1, data, data_len);
+
+        msgs[0].addr = client->addr;
+        msgs[0].flags = client->flags;
+        msgs[0].len = data_len + 1;
+        msgs[0].buf = buffer;
+
+        ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+        if (ret < 0)
+                dev_err(&client->adapter->dev, "i2c write failed\n");
+
+        kfree(buffer);
+        return ret;
+}
+
+static acpi_status
+acpi_i2c_space_handler(u32 function, acpi_physical_address command,
+                        u32 bits, u64 *value64,
+                        void *handler_context, void *region_context)
+{
+        struct gsb_buffer *gsb = (struct gsb_buffer *)value64;
+        struct acpi_i2c_handler_data *data = handler_context;
+        struct acpi_connection_info *info = &data->info;
+        struct acpi_resource_i2c_serialbus *sb;
+        struct i2c_adapter *adapter = data->adapter;
+        struct i2c_client client;
+        struct acpi_resource *ares;
+        u32 accessor_type = function >> 16;
+        u8 action = function & ACPI_IO_MASK;
+        acpi_status ret = AE_OK;
+        int status;
+
+        ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
+        if (ACPI_FAILURE(ret))
+                return ret;
+
+        if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) {
+                ret = AE_BAD_PARAMETER;
+                goto err;
+        }
+
+        sb = &ares->data.i2c_serial_bus;
+        if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) {
+                ret = AE_BAD_PARAMETER;
+                goto err;
+        }
+
+        memset(&client, 0, sizeof(client));
+        client.adapter = adapter;
+        client.addr = sb->slave_address;
+        client.flags = 0;
+
+        if (sb->access_mode == ACPI_I2C_10BIT_MODE)
+                client.flags |= I2C_CLIENT_TEN;
+
+        switch (accessor_type) {
+        case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV:
+                if (action == ACPI_READ) {
+                        status = i2c_smbus_read_byte(&client);
+                        if (status >= 0) {
+                                gsb->bdata = status;
+                                status = 0;
+                        }
+                } else {
+                        status = i2c_smbus_write_byte(&client, gsb->bdata);
+                }
+                break;
+
+        case ACPI_GSB_ACCESS_ATTRIB_BYTE:
+                if (action == ACPI_READ) {
+                        status = i2c_smbus_read_byte_data(&client, command);
+                        if (status >= 0) {
+                                gsb->bdata = status;
+                                status = 0;
+                        }
+                } else {
+                        status = i2c_smbus_write_byte_data(&client, command,
+                                        gsb->bdata);
+                }
+                break;
+
+        case ACPI_GSB_ACCESS_ATTRIB_WORD:
+                if (action == ACPI_READ) {
+                        status = i2c_smbus_read_word_data(&client, command);
+                        if (status >= 0) {
+                                gsb->wdata = status;
+                                status = 0;
+                        }
+                } else {
+                        status = i2c_smbus_write_word_data(&client, command,
+                                        gsb->wdata);
+                }
+                break;
+
+        case ACPI_GSB_ACCESS_ATTRIB_BLOCK:
+                if (action == ACPI_READ) {
+                        status = i2c_smbus_read_block_data(&client, command,
+                                        gsb->data);
+                        if (status >= 0) {
+                                gsb->len = status;
+                                status = 0;
+                        }
+                } else {
+                        status = i2c_smbus_write_block_data(&client, command,
+                                        gsb->len, gsb->data);
+                }
+                break;
+
+        case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE:
+                if (action == ACPI_READ) {
+                        status = acpi_gsb_i2c_read_bytes(&client, command,
+                                        gsb->data, info->access_length);
+                        if (status > 0)
+                                status = 0;
+                } else {
+                        status = acpi_gsb_i2c_write_bytes(&client, command,
+                                        gsb->data, info->access_length);
+                }
+                break;
+
+        default:
+                pr_info("protocol(0x%02x) is not supported.\n", accessor_type);
+                ret = AE_BAD_PARAMETER;
+                goto err;
+        }
+
+        gsb->status = status;
+
+ err:
+        ACPI_FREE(ares);
+        return ret;
+}
+
+
+static int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)
+{
+        acpi_handle handle;
+        struct acpi_i2c_handler_data *data;
+        acpi_status status;
+
+        if (!adapter->dev.parent)
+                return -ENODEV;
+
+        handle = ACPI_HANDLE(adapter->dev.parent);
+
+        if (!handle)
+                return -ENODEV;
+
+        data = kzalloc(sizeof(struct acpi_i2c_handler_data),
+                            GFP_KERNEL);
+        if (!data)
+                return -ENOMEM;
+
+        data->adapter = adapter;
+        status = acpi_bus_attach_private_data(handle, (void *)data);
+        if (ACPI_FAILURE(status)) {
+                kfree(data);
+                return -ENOMEM;
+        }
+
+        status = acpi_install_address_space_handler(handle,
+                                ACPI_ADR_SPACE_GSBUS,
+                                &acpi_i2c_space_handler,
+                                NULL,
+                                data);
+        if (ACPI_FAILURE(status)) {
+                dev_err(&adapter->dev, "Error installing i2c space handler\n");
+                acpi_bus_detach_private_data(handle);
+                kfree(data);
+                return -ENOMEM;
+        }
+
+        return 0;
+}
+
+static void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)
+{
+        acpi_handle handle;
+        struct acpi_i2c_handler_data *data;
+        acpi_status status;
+
+        if (!adapter->dev.parent)
+                return;
+
+        handle = ACPI_HANDLE(adapter->dev.parent);
+
+        if (!handle)
+                return;
+
+        acpi_remove_address_space_handler(handle,
+                                ACPI_ADR_SPACE_GSBUS,
+                                &acpi_i2c_space_handler);
+
+        status = acpi_bus_get_private_data(handle, (void **)&data);
+        if (ACPI_SUCCESS(status))
+                kfree(data);
+
+        acpi_bus_detach_private_data(handle);
+}
+#else /* CONFIG_ACPI_I2C_OPREGION */
+static inline void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)
+{ }
+
+static inline int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)
+{ return 0; }
+#endif /* CONFIG_ACPI_I2C_OPREGION */
+
 /* ------------------------------------------------------------------------- */
 
 static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id,