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>

1 files changed, 398 insertions, 0 deletions

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;
+        range = (ctrl & CMA3000_GRANGEMASK) >> 7;
+
+        data->bit_to_mg = mode_to_mg[mode][range];
+
+        /* Interrupt not for this device */
+        if (data->bit_to_mg == 0)
+                return IRQ_NONE;
+
+        /* Decode register values to milli g */
+        decode_mg(data, &datax, &datay, &dataz);
+
+        input_report_abs(data->input_dev, ABS_X, datax);
+        input_report_abs(data->input_dev, ABS_Y, datay);
+        input_report_abs(data->input_dev, ABS_Z, dataz);
+        input_sync(data->input_dev);
+
+        return IRQ_HANDLED;
+}
+
+static int cma3000_reset(struct cma3000_accl_data *data)
+{
+        int val;
+
+        /* Reset sequence */
+        CMA3000_SET(data, CMA3000_RSTR, 0x02, "Reset");
+        CMA3000_SET(data, CMA3000_RSTR, 0x0A, "Reset");
+        CMA3000_SET(data, CMA3000_RSTR, 0x04, "Reset");
+
+        /* Settling time delay */
+        mdelay(10);
+
+        val = CMA3000_READ(data, CMA3000_STATUS, "Status");
+        if (val < 0) {
+                dev_err(data->dev, "Reset failed\n");
+                return val;
+        }
+
+        if (val & CMA3000_STATUS_PERR) {
+                dev_err(data->dev, "Parity Error\n");
+                return -EIO;
+        }
+
+        return 0;
+}
+
+static int cma3000_poweron(struct cma3000_accl_data *data)
+{
+        const struct cma3000_platform_data *pdata = data->pdata;
+        u8 ctrl = 0;
+        int ret;
+
+        if (data->g_range == CMARANGE_2G) {
+                ctrl = (data->mode << 1) | CMA3000_RANGE2G;
+        } else if (data->g_range == CMARANGE_8G) {
+                ctrl = (data->mode << 1) | CMA3000_RANGE8G;
+        } else {
+                dev_info(data->dev,
+                         "Invalid G range specified, assuming 8G\n");
+                ctrl = (data->mode << 1) | CMA3000_RANGE8G;
+        }
+
+        ctrl |= data->bus_ops->ctrl_mod;
+
+        CMA3000_SET(data, CMA3000_MDTHR, pdata->mdthr,
+                    "Motion Detect Threshold");
+        CMA3000_SET(data, CMA3000_MDFFTMR, pdata->mdfftmr,
+                    "Time register");
+        CMA3000_SET(data, CMA3000_FFTHR, pdata->ffthr,
+                    "Free fall threshold");
+        ret = CMA3000_SET(data, CMA3000_CTRL, ctrl, "Mode setting");
+        if (ret < 0)
+                return -EIO;
+
+        msleep(CMA3000_SETDELAY);
+
+        return 0;
+}
+
+static int cma3000_poweroff(struct cma3000_accl_data *data)
+{
+        int ret;
+
+        ret = CMA3000_SET(data, CMA3000_CTRL, CMAMODE_POFF, "Mode setting");
+        msleep(CMA3000_SETDELAY);
+
+        return ret;
+}
+
+static int cma3000_open(struct input_dev *input_dev)
+{
+        struct cma3000_accl_data *data = input_get_drvdata(input_dev);
+
+        mutex_lock(&data->mutex);
+
+        if (!data->suspended)
+                cma3000_poweron(data);
+
+        data->opened = true;
+
+        mutex_unlock(&data->mutex);
+
+        return 0;
+}
+
+static void cma3000_close(struct input_dev *input_dev)
+{
+        struct cma3000_accl_data *data = input_get_drvdata(input_dev);
+
+        mutex_lock(&data->mutex);
+
+        if (!data->suspended)
+                cma3000_poweroff(data);
+
+        data->opened = false;
+
+        mutex_unlock(&data->mutex);
+}
+
+void cma3000_suspend(struct cma3000_accl_data *data)
+{
+        mutex_lock(&data->mutex);
+
+        if (!data->suspended && data->opened)
+                cma3000_poweroff(data);
+
+        data->suspended = true;
+
+        mutex_unlock(&data->mutex);
+}
+EXPORT_SYMBOL(cma3000_suspend);
+
+
+void cma3000_resume(struct cma3000_accl_data *data)
+{
+        mutex_lock(&data->mutex);
+
+        if (data->suspended && data->opened)
+                cma3000_poweron(data);
+
+        data->suspended = false;
+
+        mutex_unlock(&data->mutex);
+}
+EXPORT_SYMBOL(cma3000_resume);
+
+struct cma3000_accl_data *cma3000_init(struct device *dev, int irq,
+                                       const struct cma3000_bus_ops *bops)
+{
+        const struct cma3000_platform_data *pdata = dev->platform_data;
+        struct cma3000_accl_data *data;
+        struct input_dev *input_dev;
+        int rev;
+        int error;
+
+        if (!pdata) {
+                dev_err(dev, "platform data not found\n");
+                error = -EINVAL;
+                goto err_out;
+        }
+
+
+        /* if no IRQ return error */
+        if (irq == 0) {
+                error = -EINVAL;
+                goto err_out;
+        }
+
+        data = kzalloc(sizeof(struct cma3000_accl_data), GFP_KERNEL);
+        input_dev = input_allocate_device();
+        if (!data || !input_dev) {
+                error = -ENOMEM;
+                goto err_free_mem;
+        }
+
+        data->dev = dev;
+        data->input_dev = input_dev;
+        data->bus_ops = bops;
+        data->pdata = pdata;
+        data->irq = irq;
+        mutex_init(&data->mutex);
+
+        data->mode = pdata->mode;
+        if (data->mode < CMAMODE_DEFAULT || data->mode > CMAMODE_POFF) {
+                data->mode = CMAMODE_MOTDET;
+                dev_warn(dev,
+                         "Invalid mode specified, assuming Motion Detect\n");
+        }
+
+        data->g_range = pdata->g_range;
+        if (data->g_range != CMARANGE_2G && data->g_range != CMARANGE_8G) {
+                dev_info(dev,
+                         "Invalid G range specified, assuming 8G\n");
+                data->g_range = CMARANGE_8G;
+        }
+
+        input_dev->name = "cma3000-accelerometer";
+        input_dev->id.bustype = bops->bustype;
+        input_dev->open = cma3000_open;
+        input_dev->close = cma3000_close;
+
+         __set_bit(EV_ABS, input_dev->evbit);
+
+        input_set_abs_params(input_dev, ABS_X,
+                        -data->g_range, data->g_range, pdata->fuzz_x, 0);
+        input_set_abs_params(input_dev, ABS_Y,
+                        -data->g_range, data->g_range, pdata->fuzz_y, 0);
+        input_set_abs_params(input_dev, ABS_Z,
+                        -data->g_range, data->g_range, pdata->fuzz_z, 0);
+        input_set_abs_params(input_dev, ABS_MISC, 0, 1, 0, 0);
+
+        input_set_drvdata(input_dev, data);
+
+        error = cma3000_reset(data);
+        if (error)
+                goto err_free_mem;
+
+        rev = CMA3000_READ(data, CMA3000_REVID, "Revid");
+        if (rev < 0) {
+                error = rev;
+                goto err_free_mem;
+        }
+
+        pr_info("CMA3000 Accelerometer: Revision %x\n", rev);
+
+        error = request_threaded_irq(irq, NULL, cma3000_thread_irq,
+                                     pdata->irqflags | IRQF_ONESHOT,
+                                     "cma3000_d0x", data);
+        if (error) {
+                dev_err(dev, "request_threaded_irq failed\n");
+                goto err_free_mem;
+        }
+
+        error = input_register_device(data->input_dev);
+        if (error) {
+                dev_err(dev, "Unable to register input device\n");
+                goto err_free_irq;
+        }
+
+        return data;
+
+err_free_irq:
+        free_irq(irq, data);
+err_free_mem:
+        input_free_device(input_dev);
+        kfree(data);
+err_out:
+        return ERR_PTR(error);
+}
+EXPORT_SYMBOL(cma3000_init);
+
+void cma3000_exit(struct cma3000_accl_data *data)
+{
+        free_irq(data->irq, data);
+        input_unregister_device(data->input_dev);
+        kfree(data);
+}
+EXPORT_SYMBOL(cma3000_exit);
+
+MODULE_DESCRIPTION("CMA3000-D0x Accelerometer Driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Hemanth V <hemanthv@ti.com>");