Input: add CMA3000 accelerometer driver

Add support for CMA3000 Tri-axis accelerometer, which supports Motion
detect, Measurement and Free fall modes. CMA3000 supports both I2C/SPI
bus for communication, currently the driver supports I2C based
communication.

Signed-off-by: Hemanth V <hemanthv@ti.com>
Reviewed-by: Jonathan Cameron <jic23@cam.ac.uk>
Reviewed-by: Sergio Aguirre <saaguirre@ti.com>
Reviewed-by: Shubhrajyoti <Shubhrajyoti@ti.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

5 files changed, 607 insertions, 0 deletions

diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index b99b8cbde02f..f0d90172a65f 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -448,4 +448,28 @@ config INPUT_ADXL34X_SPI
           To compile this driver as a module, choose M here: the
           module will be called adxl34x-spi.
 
+config INPUT_CMA3000
+        tristate "VTI CMA3000 Tri-axis accelerometer"
+        help
+          Say Y here if you want to use VTI CMA3000_D0x Accelerometer
+          driver
+
+          This driver currently only supports I2C interface to the
+          controller. Also select the I2C method.
+
+          If unsure, say N
+
+          To compile this driver as a module, choose M here: the
+          module will be called cma3000_d0x.
+
+config INPUT_CMA3000_I2C
+        tristate "Support I2C bus connection"
+        depends on INPUT_CMA3000 && I2C
+        help
+          Say Y here if you want to use VTI CMA3000_D0x Accelerometer
+          through I2C interface.
+
+          To compile this driver as a module, choose M here: the
+          module will be called cma3000_d0x_i2c.
+
 endif
diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index 1fe1f6c8b737..35bcfe46555e 100644
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -18,6 +18,8 @@ obj-$(CONFIG_INPUT_ATI_REMOTE2)		+= ati_remote2.o
 obj-$(CONFIG_INPUT_ATLAS_BTNS)          += atlas_btns.o
 obj-$(CONFIG_INPUT_BFIN_ROTARY)         += bfin_rotary.o
 obj-$(CONFIG_INPUT_CM109)               += cm109.o
+obj-$(CONFIG_INPUT_CMA3000)             += cma3000_d0x.o
+obj-$(CONFIG_INPUT_CMA3000_I2C)         += cma3000_d0x_i2c.o
 obj-$(CONFIG_INPUT_COBALT_BTNS)         += cobalt_btns.o
 obj-$(CONFIG_INPUT_DM355EVM)            += dm355evm_keys.o
 obj-$(CONFIG_HP_SDC_RTC)                += hp_sdc_rtc.o
diff --git a/drivers/input/misc/cma3000_d0x.c b/drivers/input/misc/cma3000_d0x.c
new file mode 100644
index 000000000000..1633b6342267
--- /dev/null
+++ b/drivers/input/misc/cma3000_d0x.c
@@ -0,0 +1,398 @@
+/*
+ * VTI CMA3000_D0x Accelerometer driver
+ *
+ * Copyright (C) 2010 Texas Instruments
+ * Author: Hemanth V <hemanthv@ti.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.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/types.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/input.h>
+#include <linux/input/cma3000.h>
+
+#include "cma3000_d0x.h"
+
+#define CMA3000_WHOAMI      0x00
+#define CMA3000_REVID       0x01
+#define CMA3000_CTRL        0x02
+#define CMA3000_STATUS      0x03
+#define CMA3000_RSTR        0x04
+#define CMA3000_INTSTATUS   0x05
+#define CMA3000_DOUTX       0x06
+#define CMA3000_DOUTY       0x07
+#define CMA3000_DOUTZ       0x08
+#define CMA3000_MDTHR       0x09
+#define CMA3000_MDFFTMR     0x0A
+#define CMA3000_FFTHR       0x0B
+
+#define CMA3000_RANGE2G    (1 << 7)
+#define CMA3000_RANGE8G    (0 << 7)
+#define CMA3000_BUSI2C     (0 << 4)
+#define CMA3000_MODEMASK   (7 << 1)
+#define CMA3000_GRANGEMASK (1 << 7)
+
+#define CMA3000_STATUS_PERR    1
+#define CMA3000_INTSTATUS_FFDET (1 << 2)
+
+/* Settling time delay in ms */
+#define CMA3000_SETDELAY    30
+
+/* Delay for clearing interrupt in us */
+#define CMA3000_INTDELAY    44
+
+
+/*
+ * Bit weights in mg for bit 0, other bits need
+ * multipy factor 2^n. Eight bit is the sign bit.
+ */
+#define BIT_TO_2G  18
+#define BIT_TO_8G  71
+
+struct cma3000_accl_data {
+        const struct cma3000_bus_ops *bus_ops;
+        const struct cma3000_platform_data *pdata;
+
+        struct device *dev;
+        struct input_dev *input_dev;
+
+        int bit_to_mg;
+        int irq;
+
+        int g_range;
+        u8 mode;
+
+        struct mutex mutex;
+        bool opened;
+        bool suspended;
+};
+
+#define CMA3000_READ(data, reg, msg) \
+        (data->bus_ops->read(data->dev, reg, msg))
+#define CMA3000_SET(data, reg, val, msg) \
+        ((data)->bus_ops->write(data->dev, reg, val, msg))
+
+/*
+ * Conversion for each of the eight modes to g, depending
+ * on G range i.e 2G or 8G. Some modes always operate in
+ * 8G.
+ */
+
+static int mode_to_mg[8][2] = {
+        { 0, 0 },
+        { BIT_TO_8G, BIT_TO_2G },
+        { BIT_TO_8G, BIT_TO_2G },
+        { BIT_TO_8G, BIT_TO_8G },
+        { BIT_TO_8G, BIT_TO_8G },
+        { BIT_TO_8G, BIT_TO_2G },
+        { BIT_TO_8G, BIT_TO_2G },
+        { 0, 0},
+};
+
+static void decode_mg(struct cma3000_accl_data *data, int *datax,
+                                int *datay, int *dataz)
+{
+        /* Data in 2's complement, convert to mg */
+        *datax = ((s8)*datax) * data->bit_to_mg;
+        *datay = ((s8)*datay) * data->bit_to_mg;
+        *dataz = ((s8)*dataz) * data->bit_to_mg;
+}
+
+static irqreturn_t cma3000_thread_irq(int irq, void *dev_id)
+{
+        struct cma3000_accl_data *data = dev_id;
+        int datax, datay, dataz;
+        u8 ctrl, mode, range, intr_status;
+
+        intr_status = CMA3000_READ(data, CMA3000_INTSTATUS, "interrupt status");
+        if (intr_status < 0)
+                return IRQ_NONE;
+
+        /* Check if free fall is detected, report immediately */
+        if (intr_status & CMA3000_INTSTATUS_FFDET) {
+                input_report_abs(data->input_dev, ABS_MISC, 1);
+                input_sync(data->input_dev);
+        } else {
+                input_report_abs(data->input_dev, ABS_MISC, 0);
+        }
+
+        datax = CMA3000_READ(data, CMA3000_DOUTX, "X");
+        datay = CMA3000_READ(data, CMA3000_DOUTY, "Y");
+        dataz = CMA3000_READ(data, CMA3000_DOUTZ, "Z");
+
+        ctrl = CMA3000_READ(data, CMA3000_CTRL, "ctrl");
+        mode = (ctrl & CMA3000_MODEMASK) >> 1;