Invensense MPU6050 Device Driver.
authorGe Gao <ggao@invensense.com>
Sat, 2 Feb 2013 00:26:00 +0000 (00:26 +0000)
committerJonathan Cameron <jic23@kernel.org>
Sun, 10 Feb 2013 17:42:43 +0000 (17:42 +0000)
This the basic functional Invensense MPU6050 Device driver.

Signed-off-by: Ge Gao <ggao@invensense.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Documentation/ABI/testing/sysfs-bus-iio-mpu6050 [new file with mode: 0644]
drivers/iio/imu/Kconfig
drivers/iio/imu/Makefile
drivers/iio/imu/inv_mpu6050/Kconfig [new file with mode: 0644]
drivers/iio/imu/inv_mpu6050/Makefile [new file with mode: 0644]
drivers/iio/imu/inv_mpu6050/inv_mpu_core.c [new file with mode: 0644]
drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h [new file with mode: 0644]
drivers/iio/imu/inv_mpu6050/inv_mpu_ring.c [new file with mode: 0644]
drivers/iio/imu/inv_mpu6050/inv_mpu_trigger.c [new file with mode: 0644]
include/linux/platform_data/invensense_mpu6050.h [new file with mode: 0644]

diff --git a/Documentation/ABI/testing/sysfs-bus-iio-mpu6050 b/Documentation/ABI/testing/sysfs-bus-iio-mpu6050
new file mode 100644 (file)
index 0000000..cb53737
--- /dev/null
@@ -0,0 +1,13 @@
+What:           /sys/bus/iio/devices/iio:deviceX/in_gyro_matrix
+What:           /sys/bus/iio/devices/iio:deviceX/in_accel_matrix
+What:           /sys/bus/iio/devices/iio:deviceX/in_magn_matrix
+KernelVersion:  3.4.0
+Contact:        linux-iio@vger.kernel.org
+Description:
+               This is mounting matrix for motion sensors. Mounting matrix
+               is a 3x3 unitary matrix. A typical mounting matrix would look like
+               [0, 1, 0; 1, 0, 0; 0, 0, -1]. Using this information, it would be
+               easy to tell the relative positions among sensors as well as their
+               positions relative to the board that holds these sensors. Identity matrix
+               [1, 0, 0; 0, 1, 0; 0, 0, 1] means sensor chip and device are perfectly
+               aligned with each other. All axes are exactly the same.
index 47f66ed9c4efad7119557f9f2fcb9e194fbe88fc..4f40a10cb74f46478dfa7c755743ab6302d916af 100644 (file)
@@ -36,3 +36,5 @@ config IIO_ADIS_LIB_BUFFER
        help
          A set of buffer helper functions for the Analog Devices ADIS* device
          family.
+
+source "drivers/iio/imu/inv_mpu6050/Kconfig"
index 019b717c5ff1bba35ede9d809fe06e6ddb2c549d..f2f56ceaed26a26c783fc34f30a7037108858a7d 100644 (file)
@@ -11,3 +11,5 @@ adis_lib-y += adis.o
 adis_lib-$(CONFIG_IIO_ADIS_LIB_BUFFER) += adis_trigger.o
 adis_lib-$(CONFIG_IIO_ADIS_LIB_BUFFER) += adis_buffer.o
 obj-$(CONFIG_IIO_ADIS_LIB) += adis_lib.o
+
+obj-y += inv_mpu6050/
diff --git a/drivers/iio/imu/inv_mpu6050/Kconfig b/drivers/iio/imu/inv_mpu6050/Kconfig
new file mode 100644 (file)
index 0000000..b5cfa3a
--- /dev/null
@@ -0,0 +1,13 @@
+#
+# inv-mpu6050 drivers for Invensense MPU devices and combos
+#
+
+config INV_MPU6050_IIO
+       tristate "Invensense MPU6050 devices"
+       depends on I2C && SYSFS
+       select IIO_TRIGGERED_BUFFER
+       help
+         This driver supports the Invensense MPU6050 devices.
+         It is a gyroscope/accelerometer combo device.
+         This driver can be built as a module. The module will be called
+         inv-mpu6050.
diff --git a/drivers/iio/imu/inv_mpu6050/Makefile b/drivers/iio/imu/inv_mpu6050/Makefile
new file mode 100644 (file)
index 0000000..3a677c7
--- /dev/null
@@ -0,0 +1,6 @@
+#
+# Makefile for Invensense MPU6050 device.
+#
+
+obj-$(CONFIG_INV_MPU6050_IIO) += inv-mpu6050.o
+inv-mpu6050-objs := inv_mpu_core.o inv_mpu_ring.o inv_mpu_trigger.o
diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
new file mode 100644 (file)
index 0000000..37ca05b
--- /dev/null
@@ -0,0 +1,795 @@
+/*
+* Copyright (C) 2012 Invensense, Inc.
+*
+* This software is licensed under the terms of the GNU General Public
+* License version 2, as published by the Free Software Foundation, and
+* may be copied, distributed, and modified under those terms.
+*
+* 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/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/sysfs.h>
+#include <linux/jiffies.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/kfifo.h>
+#include <linux/spinlock.h>
+#include "inv_mpu_iio.h"
+
+/*
+ * this is the gyro scale translated from dynamic range plus/minus
+ * {250, 500, 1000, 2000} to rad/s
+ */
+static const int gyro_scale_6050[] = {133090, 266181, 532362, 1064724};
+
+/*
+ * this is the accel scale translated from dynamic range plus/minus
+ * {2, 4, 8, 16} to m/s^2
+ */
+static const int accel_scale[] = {598, 1196, 2392, 4785};
+
+static const struct inv_mpu6050_reg_map reg_set_6050 = {
+       .sample_rate_div        = INV_MPU6050_REG_SAMPLE_RATE_DIV,
+       .lpf                    = INV_MPU6050_REG_CONFIG,
+       .user_ctrl              = INV_MPU6050_REG_USER_CTRL,
+       .fifo_en                = INV_MPU6050_REG_FIFO_EN,
+       .gyro_config            = INV_MPU6050_REG_GYRO_CONFIG,
+       .accl_config            = INV_MPU6050_REG_ACCEL_CONFIG,
+       .fifo_count_h           = INV_MPU6050_REG_FIFO_COUNT_H,
+       .fifo_r_w               = INV_MPU6050_REG_FIFO_R_W,
+       .raw_gyro               = INV_MPU6050_REG_RAW_GYRO,
+       .raw_accl               = INV_MPU6050_REG_RAW_ACCEL,
+       .temperature            = INV_MPU6050_REG_TEMPERATURE,
+       .int_enable             = INV_MPU6050_REG_INT_ENABLE,
+       .pwr_mgmt_1             = INV_MPU6050_REG_PWR_MGMT_1,
+       .pwr_mgmt_2             = INV_MPU6050_REG_PWR_MGMT_2,
+};
+
+static const struct inv_mpu6050_chip_config chip_config_6050 = {
+       .fsr = INV_MPU6050_FSR_2000DPS,
+       .lpf = INV_MPU6050_FILTER_20HZ,
+       .fifo_rate = INV_MPU6050_INIT_FIFO_RATE,
+       .gyro_fifo_enable = false,
+       .accl_fifo_enable = false,
+       .accl_fs = INV_MPU6050_FS_02G,
+};
+
+static const struct inv_mpu6050_hw hw_info[INV_NUM_PARTS] = {
+       {
+               .num_reg = 117,
+               .name = "MPU6050",
+               .reg = &reg_set_6050,
+               .config = &chip_config_6050,
+       },
+};
+
+int inv_mpu6050_write_reg(struct inv_mpu6050_state *st, int reg, u8 d)
+{
+       return i2c_smbus_write_i2c_block_data(st->client, reg, 1, &d);
+}
+
+int inv_mpu6050_switch_engine(struct inv_mpu6050_state *st, bool en, u32 mask)
+{
+       u8 d, mgmt_1;
+       int result;
+
+       /* switch clock needs to be careful. Only when gyro is on, can
+          clock source be switched to gyro. Otherwise, it must be set to
+          internal clock */
+       if (INV_MPU6050_BIT_PWR_GYRO_STBY == mask) {
+               result = i2c_smbus_read_i2c_block_data(st->client,
+                                      st->reg->pwr_mgmt_1, 1, &mgmt_1);
+               if (result != 1)
+                       return result;
+
+               mgmt_1 &= ~INV_MPU6050_BIT_CLK_MASK;
+       }
+
+       if ((INV_MPU6050_BIT_PWR_GYRO_STBY == mask) && (!en)) {
+               /* turning off gyro requires switch to internal clock first.
+                  Then turn off gyro engine */
+               mgmt_1 |= INV_CLK_INTERNAL;
+               result = inv_mpu6050_write_reg(st, st->reg->pwr_mgmt_1, mgmt_1);
+               if (result)
+                       return result;
+       }
+
+       result = i2c_smbus_read_i2c_block_data(st->client,
+                                      st->reg->pwr_mgmt_2, 1, &d);
+       if (result != 1)
+               return result;
+       if (en)
+               d &= ~mask;
+       else
+               d |= mask;
+       result = inv_mpu6050_write_reg(st, st->reg->pwr_mgmt_2, d);
+       if (result)
+               return result;
+
+       if (en) {
+               /* Wait for output stablize */
+               msleep(INV_MPU6050_TEMP_UP_TIME);
+               if (INV_MPU6050_BIT_PWR_GYRO_STBY == mask) {
+                       /* switch internal clock to PLL */
+                       mgmt_1 |= INV_CLK_PLL;
+                       result = inv_mpu6050_write_reg(st,
+                                       st->reg->pwr_mgmt_1, mgmt_1);
+                       if (result)
+                               return result;
+               }
+       }
+
+       return 0;
+}
+
+int inv_mpu6050_set_power_itg(struct inv_mpu6050_state *st, bool power_on)
+{
+       int result;
+
+       if (power_on)
+               result = inv_mpu6050_write_reg(st, st->reg->pwr_mgmt_1, 0);
+       else
+               result = inv_mpu6050_write_reg(st, st->reg->pwr_mgmt_1,
+                                               INV_MPU6050_BIT_SLEEP);
+       if (result)
+               return result;
+
+       if (power_on)
+               msleep(INV_MPU6050_REG_UP_TIME);
+
+       return 0;
+}
+
+/**
+ *  inv_mpu6050_init_config() - Initialize hardware, disable FIFO.
+ *
+ *  Initial configuration:
+ *  FSR: ± 2000DPS
+ *  DLPF: 20Hz
+ *  FIFO rate: 50Hz
+ *  Clock source: Gyro PLL
+ */
+static int inv_mpu6050_init_config(struct iio_dev *indio_dev)
+{
+       int result;
+       u8 d;
+       struct inv_mpu6050_state *st = iio_priv(indio_dev);
+
+       result = inv_mpu6050_set_power_itg(st, true);
+       if (result)
+               return result;
+       d = (INV_MPU6050_FSR_2000DPS << INV_MPU6050_GYRO_CONFIG_FSR_SHIFT);
+       result = inv_mpu6050_write_reg(st, st->reg->gyro_config, d);
+       if (result)
+               return result;
+
+       d = INV_MPU6050_FILTER_20HZ;
+       result = inv_mpu6050_write_reg(st, st->reg->lpf, d);
+       if (result)
+               return result;
+
+       d = INV_MPU6050_ONE_K_HZ / INV_MPU6050_INIT_FIFO_RATE - 1;
+       result = inv_mpu6050_write_reg(st, st->reg->sample_rate_div, d);
+       if (result)
+               return result;
+
+       d = (INV_MPU6050_FS_02G << INV_MPU6050_ACCL_CONFIG_FSR_SHIFT);
+       result = inv_mpu6050_write_reg(st, st->reg->accl_config, d);
+       if (result)
+               return result;
+
+       memcpy(&st->chip_config, hw_info[st->chip_type].config,
+               sizeof(struct inv_mpu6050_chip_config));
+       result = inv_mpu6050_set_power_itg(st, false);
+
+       return result;
+}
+
+static int inv_mpu6050_sensor_show(struct inv_mpu6050_state  *st, int reg,
+                               int axis, int *val)
+{
+       int ind, result;
+       __be16 d;
+
+       ind = (axis - IIO_MOD_X) * 2;
+       result = i2c_smbus_read_i2c_block_data(st->client, reg + ind,  2,
+                                               (u8 *)&d);
+       if (result != 2)
+               return -EINVAL;
+       *val = (short)be16_to_cpup(&d);
+
+       return IIO_VAL_INT;
+}
+
+static int inv_mpu6050_read_raw(struct iio_dev *indio_dev,
+                             struct iio_chan_spec const *chan,
+                             int *val,
+                             int *val2,
+                             long mask) {
+       struct inv_mpu6050_state  *st = iio_priv(indio_dev);
+
+       switch (mask) {
+       case IIO_CHAN_INFO_RAW:
+       {
+               int ret, result;
+
+               ret = IIO_VAL_INT;
+               result = 0;
+               mutex_lock(&indio_dev->mlock);
+               if (!st->chip_config.enable) {
+                       result = inv_mpu6050_set_power_itg(st, true);
+                       if (result)
+                               goto error_read_raw;
+               }
+               /* when enable is on, power is already on */
+               switch (chan->type) {
+               case IIO_ANGL_VEL:
+                       if (!st->chip_config.gyro_fifo_enable ||
+                                       !st->chip_config.enable) {
+                               result = inv_mpu6050_switch_engine(st, true,
+                                               INV_MPU6050_BIT_PWR_GYRO_STBY);
+                               if (result)
+                                       goto error_read_raw;
+                       }
+                       ret =  inv_mpu6050_sensor_show(st, st->reg->raw_gyro,
+                                               chan->channel2, val);
+                       if (!st->chip_config.gyro_fifo_enable ||
+                                       !st->chip_config.enable) {
+                               result = inv_mpu6050_switch_engine(st, false,
+                                               INV_MPU6050_BIT_PWR_GYRO_STBY);
+                               if (result)
+                                       goto error_read_raw;
+                       }
+                       break;
+               case IIO_ACCEL:
+                       if (!st->chip_config.accl_fifo_enable ||
+                                       !st->chip_config.enable) {
+                               result = inv_mpu6050_switch_engine(st, true,
+                                               INV_MPU6050_BIT_PWR_ACCL_STBY);
+                               if (result)
+                                       goto error_read_raw;
+                       }
+                       ret = inv_mpu6050_sensor_show(st, st->reg->raw_accl,
+                                               chan->channel2, val);
+                       if (!st->chip_config.accl_fifo_enable ||
+                                       !st->chip_config.enable) {
+                               result = inv_mpu6050_switch_engine(st, false,
+                                               INV_MPU6050_BIT_PWR_ACCL_STBY);
+                               if (result)
+                                       goto error_read_raw;
+                       }
+                       break;
+               case IIO_TEMP:
+                       /* wait for stablization */
+                       msleep(INV_MPU6050_SENSOR_UP_TIME);
+                       inv_mpu6050_sensor_show(st, st->reg->temperature,
+                                                       IIO_MOD_X, val);
+                       break;
+               default:
+                       ret = -EINVAL;
+                       break;
+               }
+error_read_raw:
+               if (!st->chip_config.enable)
+                       result |= inv_mpu6050_set_power_itg(st, false);
+               mutex_unlock(&indio_dev->mlock);
+               if (result)
+                       return result;
+
+               return ret;
+       }
+       case IIO_CHAN_INFO_SCALE:
+               switch (chan->type) {
+               case IIO_ANGL_VEL:
+                       *val  = 0;
+                       *val2 = gyro_scale_6050[st->chip_config.fsr];
+
+                       return IIO_VAL_INT_PLUS_NANO;
+               case IIO_ACCEL:
+                       *val = 0;
+                       *val2 = accel_scale[st->chip_config.accl_fs];
+
+                       return IIO_VAL_INT_PLUS_MICRO;
+               case IIO_TEMP:
+                       *val = 0;
+                       *val2 = INV_MPU6050_TEMP_SCALE;
+
+                       return IIO_VAL_INT_PLUS_MICRO;
+               default:
+                       return -EINVAL;
+               }
+       case IIO_CHAN_INFO_OFFSET:
+               switch (chan->type) {
+               case IIO_TEMP:
+                       *val = INV_MPU6050_TEMP_OFFSET;
+
+                       return IIO_VAL_INT;
+               default:
+                       return -EINVAL;
+               }
+       default:
+               return -EINVAL;
+       }
+}
+
+static int inv_mpu6050_write_fsr(struct inv_mpu6050_state *st, int fsr)
+{
+       int result;
+       u8 d;
+
+       if (fsr < 0 || fsr > INV_MPU6050_MAX_GYRO_FS_PARAM)
+               return -EINVAL;
+       if (fsr == st->chip_config.fsr)
+               return 0;
+
+       d = (fsr << INV_MPU6050_GYRO_CONFIG_FSR_SHIFT);
+       result = inv_mpu6050_write_reg(st, st->reg->gyro_config, d);
+       if (result)
+               return result;
+       st->chip_config.fsr = fsr;
+
+       return 0;
+}
+
+static int inv_mpu6050_write_accel_fs(struct inv_mpu6050_state *st, int fs)
+{
+       int result;
+       u8 d;
+
+       if (fs < 0 || fs > INV_MPU6050_MAX_ACCL_FS_PARAM)
+               return -EINVAL;
+       if (fs == st->chip_config.accl_fs)
+               return 0;
+
+       d = (fs << INV_MPU6050_ACCL_CONFIG_FSR_SHIFT);
+       result = inv_mpu6050_write_reg(st, st->reg->accl_config, d);
+       if (result)
+               return result;
+       st->chip_config.accl_fs = fs;
+
+       return 0;
+}
+
+static int inv_mpu6050_write_raw(struct iio_dev *indio_dev,
+                              struct iio_chan_spec const *chan,
+                              int val,
+                              int val2,
+                              long mask) {
+       struct inv_mpu6050_state  *st = iio_priv(indio_dev);
+       int result;
+
+       mutex_lock(&indio_dev->mlock);
+       /* we should only update scale when the chip is disabled, i.e.,
+               not running */
+       if (st->chip_config.enable) {
+               result = -EBUSY;
+               goto error_write_raw;
+       }
+       result = inv_mpu6050_set_power_itg(st, true);
+       if (result)
+               goto error_write_raw;
+
+       switch (mask) {
+       case IIO_CHAN_INFO_SCALE:
+               switch (chan->type) {
+               case IIO_ANGL_VEL:
+                       result = inv_mpu6050_write_fsr(st, val);
+                       break;
+               case IIO_ACCEL:
+                       result = inv_mpu6050_write_accel_fs(st, val);
+                       break;
+               default:
+                       result = -EINVAL;
+                       break;
+               }
+               break;
+       default:
+               result = -EINVAL;
+               break;
+       }
+
+error_write_raw:
+       result |= inv_mpu6050_set_power_itg(st, false);
+       mutex_unlock(&indio_dev->mlock);
+
+       return result;
+}
+
+/**
+ *  inv_mpu6050_set_lpf() - set low pass filer based on fifo rate.
+ *
+ *                  Based on the Nyquist principle, the sampling rate must
+ *                  exceed twice of the bandwidth of the signal, or there
+ *                  would be alising. This function basically search for the
+ *                  correct low pass parameters based on the fifo rate, e.g,
+ *                  sampling frequency.
+ */
+static int inv_mpu6050_set_lpf(struct inv_mpu6050_state *st, int rate)
+{
+       const int hz[] = {188, 98, 42, 20, 10, 5};
+       const int d[] = {INV_MPU6050_FILTER_188HZ, INV_MPU6050_FILTER_98HZ,
+                       INV_MPU6050_FILTER_42HZ, INV_MPU6050_FILTER_20HZ,
+                       INV_MPU6050_FILTER_10HZ, INV_MPU6050_FILTER_5HZ};
+       int i, h, result;
+       u8 data;
+
+       h = (rate >> 1);
+       i = 0;
+       while ((h < hz[i]) && (i < ARRAY_SIZE(d) - 1))
+               i++;
+       data = d[i];
+       result = inv_mpu6050_write_reg(st, st->reg->lpf, data);
+       if (result)
+               return result;
+       st->chip_config.lpf = data;
+
+       return 0;
+}
+
+/**
+ * inv_mpu6050_fifo_rate_store() - Set fifo rate.
+ */
+static ssize_t inv_mpu6050_fifo_rate_store(struct device *dev,
+       struct device_attribute *attr, const char *buf, size_t count)
+{
+       s32 fifo_rate;
+       u8 d;
+       int result;
+       struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+       struct inv_mpu6050_state *st = iio_priv(indio_dev);
+
+       if (kstrtoint(buf, 10, &fifo_rate))
+               return -EINVAL;
+       if (fifo_rate < INV_MPU6050_MIN_FIFO_RATE ||
+                               fifo_rate > INV_MPU6050_MAX_FIFO_RATE)
+               return -EINVAL;
+       if (fifo_rate == st->chip_config.fifo_rate)
+               return count;
+
+       mutex_lock(&indio_dev->mlock);
+       if (st->chip_config.enable) {
+               result = -EBUSY;
+               goto fifo_rate_fail;
+       }
+       result = inv_mpu6050_set_power_itg(st, true);
+       if (result)
+               goto fifo_rate_fail;
+
+       d = INV_MPU6050_ONE_K_HZ / fifo_rate - 1;
+       result = inv_mpu6050_write_reg(st, st->reg->sample_rate_div, d);
+       if (result)
+               goto fifo_rate_fail;
+       st->chip_config.fifo_rate = fifo_rate;
+
+       result = inv_mpu6050_set_lpf(st, fifo_rate);
+       if (result)
+               goto fifo_rate_fail;
+
+fifo_rate_fail:
+       result |= inv_mpu6050_set_power_itg(st, false);
+       mutex_unlock(&indio_dev->mlock);
+       if (result)
+               return result;
+
+       return count;
+}
+
+/**
+ * inv_fifo_rate_show() - Get the current sampling rate.
+ */
+static ssize_t inv_fifo_rate_show(struct device *dev,
+       struct device_attribute *attr, char *buf)
+{
+       struct inv_mpu6050_state *st = iio_priv(dev_to_iio_dev(dev));
+
+       return sprintf(buf, "%d\n", st->chip_config.fifo_rate);
+}
+
+/**
+ * inv_attr_show() - calling this function will show current
+ *                    parameters.
+ */
+static ssize_t inv_attr_show(struct device *dev,
+       struct device_attribute *attr, char *buf)
+{
+       struct inv_mpu6050_state *st = iio_priv(dev_to_iio_dev(dev));
+       struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+       s8 *m;
+
+       switch (this_attr->address) {
+       /* In MPU6050, the two matrix are the same because gyro and accel
+          are integrated in one chip */
+       case ATTR_GYRO_MATRIX:
+       case ATTR_ACCL_MATRIX:
+               m = st->plat_data.orientation;
+
+               return sprintf(buf, "%d, %d, %d; %d, %d, %d; %d, %d, %d\n",
+                       m[0], m[1], m[2], m[3], m[4], m[5], m[6], m[7], m[8]);
+       default:
+               return -EINVAL;
+       }
+}
+
+/**
+ * inv_mpu6050_validate_trigger() - validate_trigger callback for invensense
+ *                                  MPU6050 device.
+ * @indio_dev: The IIO device
+ * @trig: The new trigger
+ *
+ * Returns: 0 if the 'trig' matches the trigger registered by the MPU6050
+ * device, -EINVAL otherwise.
+ */
+static int inv_mpu6050_validate_trigger(struct iio_dev *indio_dev,
+                                       struct iio_trigger *trig)
+{
+       struct inv_mpu6050_state *st = iio_priv(indio_dev);
+
+       if (st->trig != trig)
+               return -EINVAL;
+
+       return 0;
+}
+
+#define INV_MPU6050_CHAN(_type, _channel2, _index)                    \
+       {                                                             \
+               .type = _type,                                        \
+               .modified = 1,                                        \
+               .channel2 = _channel2,                                \
+               .info_mask =  IIO_CHAN_INFO_SCALE_SHARED_BIT          \
+                               | IIO_CHAN_INFO_RAW_SEPARATE_BIT,     \
+               .scan_index = _index,                                 \
+               .scan_type = {                                        \
+                               .sign = 's',                          \
+                               .realbits = 16,                       \
+                               .storagebits = 16,                    \
+                               .shift = 0 ,                          \
+                               .endianness = IIO_BE,                 \
+                            },                                       \
+       }
+
+static const struct iio_chan_spec inv_mpu_channels[] = {
+       IIO_CHAN_SOFT_TIMESTAMP(INV_MPU6050_SCAN_TIMESTAMP),
+       /*
+        * Note that temperature should only be via polled reading only,
+        * not the final scan elements output.
+        */
+       {
+               .type = IIO_TEMP,
+               .info_mask =  IIO_CHAN_INFO_RAW_SEPARATE_BIT
+                               | IIO_CHAN_INFO_OFFSET_SEPARATE_BIT
+                               | IIO_CHAN_INFO_SCALE_SEPARATE_BIT,
+               .scan_index = -1,
+       },
+       INV_MPU6050_CHAN(IIO_ANGL_VEL, IIO_MOD_X, INV_MPU6050_SCAN_GYRO_X),
+       INV_MPU6050_CHAN(IIO_ANGL_VEL, IIO_MOD_Y, INV_MPU6050_SCAN_GYRO_Y),
+       INV_MPU6050_CHAN(IIO_ANGL_VEL, IIO_MOD_Z, INV_MPU6050_SCAN_GYRO_Z),
+
+       INV_MPU6050_CHAN(IIO_ACCEL, IIO_MOD_X, INV_MPU6050_SCAN_ACCL_X),
+       INV_MPU6050_CHAN(IIO_ACCEL, IIO_MOD_Y, INV_MPU6050_SCAN_ACCL_Y),
+       INV_MPU6050_CHAN(IIO_ACCEL, IIO_MOD_Z, INV_MPU6050_SCAN_ACCL_Z),
+};
+
+/* constant IIO attribute */
+static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("10 20 50 100 200 500");
+static IIO_DEV_ATTR_SAMP_FREQ(S_IRUGO | S_IWUSR, inv_fifo_rate_show,
+       inv_mpu6050_fifo_rate_store);
+static IIO_DEVICE_ATTR(in_gyro_matrix, S_IRUGO, inv_attr_show, NULL,
+       ATTR_GYRO_MATRIX);
+static IIO_DEVICE_ATTR(in_accel_matrix, S_IRUGO, inv_attr_show, NULL,
+       ATTR_ACCL_MATRIX);
+
+static struct attribute *inv_attributes[] = {
+       &iio_dev_attr_in_gyro_matrix.dev_attr.attr,
+       &iio_dev_attr_in_accel_matrix.dev_attr.attr,
+       &iio_dev_attr_sampling_frequency.dev_attr.attr,
+       &iio_const_attr_sampling_frequency_available.dev_attr.attr,
+       NULL,
+};
+
+static const struct attribute_group inv_attribute_group = {
+       .attrs = inv_attributes
+};
+
+static const struct iio_info mpu_info = {
+       .driver_module = THIS_MODULE,
+       .read_raw = &inv_mpu6050_read_raw,
+       .write_raw = &inv_mpu6050_write_raw,
+       .attrs = &inv_attribute_group,
+       .validate_trigger = inv_mpu6050_validate_trigger,
+};
+
+/**
+ *  inv_check_and_setup_chip() - check and setup chip.
+ */
+static int inv_check_and_setup_chip(struct inv_mpu6050_state *st,
+               const struct i2c_device_id *id)
+{
+       int result;
+
+       st->chip_type = INV_MPU6050;
+       st->hw  = &hw_info[st->chip_type];
+       st->reg = hw_info[st->chip_type].reg;
+
+       /* reset to make sure previous state are not there */
+       result = inv_mpu6050_write_reg(st, st->reg->pwr_mgmt_1,
+                                       INV_MPU6050_BIT_H_RESET);
+       if (result)
+               return result;
+       msleep(INV_MPU6050_POWER_UP_TIME);
+       /* toggle power state. After reset, the sleep bit could be on
+               or off depending on the OTP settings. Toggling power would
+               make it in a definite state as well as making the hardware
+               state align with the software state */
+       result = inv_mpu6050_set_power_itg(st, false);
+       if (result)
+               return result;
+       result = inv_mpu6050_set_power_itg(st, true);
+       if (result)
+               return result;
+
+       result = inv_mpu6050_switch_engine(st, false,
+                                       INV_MPU6050_BIT_PWR_ACCL_STBY);
+       if (result)
+               return result;
+       result = inv_mpu6050_switch_engine(st, false,
+                                       INV_MPU6050_BIT_PWR_GYRO_STBY);
+       if (result)
+               return result;
+
+       return 0;
+}
+
+/**
+ *  inv_mpu_probe() - probe function.
+ *  @client:          i2c client.
+ *  @id:              i2c device id.
+ *
+ *  Returns 0 on success, a negative error code otherwise.
+ */
+static int inv_mpu_probe(struct i2c_client *client,
+       const struct i2c_device_id *id)
+{
+       struct inv_mpu6050_state *st;
+       struct iio_dev *indio_dev;
+       int result;
+
+       if (!i2c_check_functionality(client->adapter,
+                                       I2C_FUNC_SMBUS_READ_I2C_BLOCK |
+                                       I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)) {
+               result = -ENOSYS;
+               goto out_no_free;
+       }
+       indio_dev = iio_device_alloc(sizeof(*st));
+       if (indio_dev == NULL) {
+               result =  -ENOMEM;
+               goto out_no_free;
+       }
+       st = iio_priv(indio_dev);
+       st->client = client;
+       st->plat_data = *(struct inv_mpu6050_platform_data
+                               *)dev_get_platdata(&client->dev);
+       /* power is turned on inside check chip type*/
+       result = inv_check_and_setup_chip(st, id);
+       if (result)
+               goto out_free;
+
+       result = inv_mpu6050_init_config(indio_dev);
+       if (result) {
+               dev_err(&client->dev,
+                       "Could not initialize device.\n");
+               goto out_free;
+       }
+
+       i2c_set_clientdata(client, indio_dev);
+       indio_dev->dev.parent = &client->dev;
+       indio_dev->name = id->name;
+       indio_dev->channels = inv_mpu_channels;
+       indio_dev->num_channels = ARRAY_SIZE(inv_mpu_channels);
+
+       indio_dev->info = &mpu_info;
+       indio_dev->modes = INDIO_BUFFER_TRIGGERED;
+
+       result = iio_triggered_buffer_setup(indio_dev,
+                                           inv_mpu6050_irq_handler,
+                                           inv_mpu6050_read_fifo,
+                                           NULL);
+       if (result) {
+               dev_err(&st->client->dev, "configure buffer fail %d\n",
+                               result);
+               goto out_free;
+       }
+       result = inv_mpu6050_probe_trigger(indio_dev);
+       if (result) {
+               dev_err(&st->client->dev, "trigger probe fail %d\n", result);
+               goto out_unreg_ring;
+       }
+
+       INIT_KFIFO(st->timestamps);
+       spin_lock_init(&st->time_stamp_lock);
+       result = iio_device_register(indio_dev);
+       if (result) {
+               dev_err(&st->client->dev, "IIO register fail %d\n", result);
+               goto out_remove_trigger;
+       }
+
+       return 0;
+
+out_remove_trigger:
+       inv_mpu6050_remove_trigger(st);
+out_unreg_ring:
+       iio_triggered_buffer_cleanup(indio_dev);
+out_free:
+       iio_device_free(indio_dev);
+out_no_free:
+
+       return result;
+}
+
+static int inv_mpu_remove(struct i2c_client *client)
+{
+       struct iio_dev *indio_dev = i2c_get_clientdata(client);
+       struct inv_mpu6050_state *st = iio_priv(indio_dev);
+
+       iio_device_unregister(indio_dev);
+       inv_mpu6050_remove_trigger(st);
+       iio_triggered_buffer_cleanup(indio_dev);
+       iio_device_free(indio_dev);
+
+       return 0;
+}
+#ifdef CONFIG_PM_SLEEP
+
+static int inv_mpu_resume(struct device *dev)
+{
+       return inv_mpu6050_set_power_itg(
+               iio_priv(i2c_get_clientdata(to_i2c_client(dev))), true);
+}
+
+static int inv_mpu_suspend(struct device *dev)
+{
+       return inv_mpu6050_set_power_itg(
+               iio_priv(i2c_get_clientdata(to_i2c_client(dev))), false);
+}
+static SIMPLE_DEV_PM_OPS(inv_mpu_pmops, inv_mpu_suspend, inv_mpu_resume);
+
+#define INV_MPU6050_PMOPS (&inv_mpu_pmops)
+#else
+#define INV_MPU6050_PMOPS NULL
+#endif /* CONFIG_PM_SLEEP */
+
+/*
+ * device id table is used to identify what device can be
+ * supported by this driver
+ */
+static const struct i2c_device_id inv_mpu_id[] = {
+       {"mpu6050", INV_MPU6050},
+       {}
+};
+
+MODULE_DEVICE_TABLE(i2c, inv_mpu_id);
+
+static struct i2c_driver inv_mpu_driver = {
+       .probe          =       inv_mpu_probe,
+       .remove         =       inv_mpu_remove,
+       .id_table       =       inv_mpu_id,
+       .driver = {
+               .owner  =       THIS_MODULE,
+               .name   =       "inv-mpu6050",
+               .pm     =       INV_MPU6050_PMOPS,
+       },
+};
+
+module_i2c_driver(inv_mpu_driver);
+
+MODULE_AUTHOR("Invensense Corporation");
+MODULE_DESCRIPTION("Invensense device MPU6050 driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h
new file mode 100644 (file)
index 0000000..f383955
--- /dev/null
@@ -0,0 +1,246 @@
+/*
+* Copyright (C) 2012 Invensense, Inc.
+*
+* This software is licensed under the terms of the GNU General Public
+* License version 2, as published by the Free Software Foundation, and
+* may be copied, distributed, and modified under those terms.
+*
+* 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/i2c.h>
+#include <linux/kfifo.h>
+#include <linux/spinlock.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/kfifo_buf.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/platform_data/invensense_mpu6050.h>
+
+/**
+ *  struct inv_mpu6050_reg_map - Notable registers.
+ *  @sample_rate_div:  Divider applied to gyro output rate.
+ *  @lpf:              Configures internal low pass filter.
+ *  @user_ctrl:                Enables/resets the FIFO.
+ *  @fifo_en:          Determines which data will appear in FIFO.
+ *  @gyro_config:      gyro config register.
+ *  @accl_config:      accel config register
+ *  @fifo_count_h:     Upper byte of FIFO count.
+ *  @fifo_r_w:         FIFO register.
+ *  @raw_gyro:         Address of first gyro register.
+ *  @raw_accl:         Address of first accel register.
+ *  @temperature:      temperature register
+ *  @int_enable:       Interrupt enable register.
+ *  @pwr_mgmt_1:       Controls chip's power state and clock source.
+ *  @pwr_mgmt_2:       Controls power state of individual sensors.
+ */
+struct inv_mpu6050_reg_map {
+       u8 sample_rate_div;
+       u8 lpf;
+       u8 user_ctrl;
+       u8 fifo_en;
+       u8 gyro_config;
+       u8 accl_config;
+       u8 fifo_count_h;
+       u8 fifo_r_w;
+       u8 raw_gyro;
+       u8 raw_accl;
+       u8 temperature;
+       u8 int_enable;
+       u8 pwr_mgmt_1;
+       u8 pwr_mgmt_2;
+};
+
+/*device enum */
+enum inv_devices {
+       INV_MPU6050,
+       INV_NUM_PARTS
+};
+
+/**
+ *  struct inv_mpu6050_chip_config - Cached chip configuration data.
+ *  @fsr:              Full scale range.
+ *  @lpf:              Digital low pass filter frequency.
+ *  @accl_fs:          accel full scale range.
+ *  @enable:           master enable state.
+ *  @accl_fifo_enable: enable accel data output
+ *  @gyro_fifo_enable: enable gyro data output
+ *  @fifo_rate:                FIFO update rate.
+ */
+struct inv_mpu6050_chip_config {
+       unsigned int fsr:2;
+       unsigned int lpf:3;
+       unsigned int accl_fs:2;
+       unsigned int enable:1;
+       unsigned int accl_fifo_enable:1;
+       unsigned int gyro_fifo_enable:1;
+       u16 fifo_rate;
+};
+
+/**
+ *  struct inv_mpu6050_hw - Other important hardware information.
+ *  @num_reg:  Number of registers on device.
+ *  @name:      name of the chip.
+ *  @reg:   register map of the chip.
+ *  @config:    configuration of the chip.
+ */
+struct inv_mpu6050_hw {
+       u8 num_reg;
+       u8 *name;
+       const struct inv_mpu6050_reg_map *reg;
+       const struct inv_mpu6050_chip_config *config;
+};
+
+/*
+ *  struct inv_mpu6050_state - Driver state variables.
+ *  @TIMESTAMP_FIFO_SIZE: fifo size for timestamp.
+ *  @trig:              IIO trigger.
+ *  @chip_config:      Cached attribute information.
+ *  @reg:              Map of important registers.
+ *  @hw:               Other hardware-specific information.
+ *  @chip_type:                chip type.
+ *  @time_stamp_lock:  spin lock to time stamp.
+ *  @client:           i2c client handle.
+ *  @plat_data:                platform data.
+ *  @timestamps:        kfifo queue to store time stamp.
+ */
+struct inv_mpu6050_state {
+#define TIMESTAMP_FIFO_SIZE 16
+       struct iio_trigger  *trig;
+       struct inv_mpu6050_chip_config chip_config;
+       const struct inv_mpu6050_reg_map *reg;
+       const struct inv_mpu6050_hw *hw;
+       enum   inv_devices chip_type;
+       spinlock_t time_stamp_lock;
+       struct i2c_client *client;
+       struct inv_mpu6050_platform_data plat_data;
+       DECLARE_KFIFO(timestamps, long long, TIMESTAMP_FIFO_SIZE);
+};
+
+/*register and associated bit definition*/
+#define INV_MPU6050_REG_SAMPLE_RATE_DIV     0x19
+#define INV_MPU6050_REG_CONFIG              0x1A
+#define INV_MPU6050_REG_GYRO_CONFIG         0x1B
+#define INV_MPU6050_REG_ACCEL_CONFIG       0x1C
+
+#define INV_MPU6050_REG_FIFO_EN             0x23
+#define INV_MPU6050_BIT_ACCEL_OUT                   0x08
+#define INV_MPU6050_BITS_GYRO_OUT                   0x70
+
+#define INV_MPU6050_REG_INT_ENABLE          0x38
+#define INV_MPU6050_BIT_DATA_RDY_EN                 0x01
+#define INV_MPU6050_BIT_DMP_INT_EN                  0x02
+
+#define INV_MPU6050_REG_RAW_ACCEL           0x3B
+#define INV_MPU6050_REG_TEMPERATURE         0x41
+#define INV_MPU6050_REG_RAW_GYRO            0x43
+
+#define INV_MPU6050_REG_USER_CTRL           0x6A
+#define INV_MPU6050_BIT_FIFO_RST                    0x04
+#define INV_MPU6050_BIT_DMP_RST                     0x08
+#define INV_MPU6050_BIT_I2C_MST_EN                  0x20
+#define INV_MPU6050_BIT_FIFO_EN                     0x40
+#define INV_MPU6050_BIT_DMP_EN                      0x80
+
+#define INV_MPU6050_REG_PWR_MGMT_1          0x6B
+#define INV_MPU6050_BIT_H_RESET                     0x80
+#define INV_MPU6050_BIT_SLEEP                       0x40
+#define INV_MPU6050_BIT_CLK_MASK                    0x7
+
+#define INV_MPU6050_REG_PWR_MGMT_2          0x6C
+#define INV_MPU6050_BIT_PWR_ACCL_STBY               0x38
+#define INV_MPU6050_BIT_PWR_GYRO_STBY               0x07
+
+#define INV_MPU6050_REG_FIFO_COUNT_H        0x72
+#define INV_MPU6050_REG_FIFO_R_W            0x74
+
+#define INV_MPU6050_BYTES_PER_3AXIS_SENSOR   6
+#define INV_MPU6050_FIFO_COUNT_BYTE          2
+#define INV_MPU6050_FIFO_THRESHOLD           500
+#define INV_MPU6050_POWER_UP_TIME            100
+#define INV_MPU6050_TEMP_UP_TIME             100
+#define INV_MPU6050_SENSOR_UP_TIME           30
+#define INV_MPU6050_REG_UP_TIME              5
+
+#define INV_MPU6050_TEMP_OFFSET                     12421
+#define INV_MPU6050_TEMP_SCALE               2941
+#define INV_MPU6050_MAX_GYRO_FS_PARAM        3
+#define INV_MPU6050_MAX_ACCL_FS_PARAM        3
+#define INV_MPU6050_THREE_AXIS               3
+#define INV_MPU6050_GYRO_CONFIG_FSR_SHIFT    3
+#define INV_MPU6050_ACCL_CONFIG_FSR_SHIFT    3
+
+/* 6 + 6 round up and plus 8 */
+#define INV_MPU6050_OUTPUT_DATA_SIZE         24
+
+/* init parameters */
+#define INV_MPU6050_INIT_FIFO_RATE           50
+#define INV_MPU6050_TIME_STAMP_TOR                        5
+#define INV_MPU6050_MAX_FIFO_RATE                         1000
+#define INV_MPU6050_MIN_FIFO_RATE                         4
+#define INV_MPU6050_ONE_K_HZ                              1000
+
+/* scan element definition */
+enum inv_mpu6050_scan {
+       INV_MPU6050_SCAN_ACCL_X,
+       INV_MPU6050_SCAN_ACCL_Y,
+       INV_MPU6050_SCAN_ACCL_Z,
+       INV_MPU6050_SCAN_GYRO_X,
+       INV_MPU6050_SCAN_GYRO_Y,
+       INV_MPU6050_SCAN_GYRO_Z,
+       INV_MPU6050_SCAN_TIMESTAMP,
+};
+
+enum inv_mpu6050_filter_e {
+       INV_MPU6050_FILTER_256HZ_NOLPF2 = 0,
+       INV_MPU6050_FILTER_188HZ,
+       INV_MPU6050_FILTER_98HZ,
+       INV_MPU6050_FILTER_42HZ,
+       INV_MPU6050_FILTER_20HZ,
+       INV_MPU6050_FILTER_10HZ,
+       INV_MPU6050_FILTER_5HZ,
+       INV_MPU6050_FILTER_2100HZ_NOLPF,
+       NUM_MPU6050_FILTER
+};
+
+/* IIO attribute address */
+enum INV_MPU6050_IIO_ATTR_ADDR {
+       ATTR_GYRO_MATRIX,
+       ATTR_ACCL_MATRIX,
+};
+
+enum inv_mpu6050_accl_fs_e {
+       INV_MPU6050_FS_02G = 0,
+       INV_MPU6050_FS_04G,
+       INV_MPU6050_FS_08G,
+       INV_MPU6050_FS_16G,
+       NUM_ACCL_FSR
+};
+
+enum inv_mpu6050_fsr_e {
+       INV_MPU6050_FSR_250DPS = 0,
+       INV_MPU6050_FSR_500DPS,
+       INV_MPU6050_FSR_1000DPS,
+       INV_MPU6050_FSR_2000DPS,
+       NUM_MPU6050_FSR
+};
+
+enum inv_mpu6050_clock_sel_e {
+       INV_CLK_INTERNAL = 0,
+       INV_CLK_PLL,
+       NUM_CLK
+};
+
+irqreturn_t inv_mpu6050_irq_handler(int irq, void *p);
+irqreturn_t inv_mpu6050_read_fifo(int irq, void *p);
+int inv_mpu6050_probe_trigger(struct iio_dev *indio_dev);
+void inv_mpu6050_remove_trigger(struct inv_mpu6050_state *st);
+int inv_reset_fifo(struct iio_dev *indio_dev);
+int inv_mpu6050_switch_engine(struct inv_mpu6050_state *st, bool en, u32 mask);
+int inv_mpu6050_write_reg(struct inv_mpu6050_state *st, int reg, u8 val);
+int inv_mpu6050_set_power_itg(struct inv_mpu6050_state *st, bool power_on);
diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_ring.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_ring.c
new file mode 100644 (file)
index 0000000..331781f
--- /dev/null
@@ -0,0 +1,196 @@
+/*
+* Copyright (C) 2012 Invensense, Inc.
+*
+* This software is licensed under the terms of the GNU General Public
+* License version 2, as published by the Free Software Foundation, and
+* may be copied, distributed, and modified under those terms.
+*
+* 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/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/sysfs.h>
+#include <linux/jiffies.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/kfifo.h>
+#include <linux/poll.h>
+#include "inv_mpu_iio.h"
+
+int inv_reset_fifo(struct iio_dev *indio_dev)
+{
+       int result;
+       u8 d;
+       struct inv_mpu6050_state  *st = iio_priv(indio_dev);
+
+       /* disable interrupt */
+       result = inv_mpu6050_write_reg(st, st->reg->int_enable, 0);
+       if (result) {
+               dev_err(&st->client->dev, "int_enable failed %d\n", result);
+               return result;
+       }
+       /* disable the sensor output to FIFO */
+       result = inv_mpu6050_write_reg(st, st->reg->fifo_en, 0);
+       if (result)
+               goto reset_fifo_fail;
+       /* disable fifo reading */
+       result = inv_mpu6050_write_reg(st, st->reg->user_ctrl, 0);
+       if (result)
+               goto reset_fifo_fail;
+
+       /* reset FIFO*/
+       result = inv_mpu6050_write_reg(st, st->reg->user_ctrl,
+                                       INV_MPU6050_BIT_FIFO_RST);
+       if (result)
+               goto reset_fifo_fail;
+       /* enable interrupt */
+       if (st->chip_config.accl_fifo_enable ||
+           st->chip_config.gyro_fifo_enable) {
+               result = inv_mpu6050_write_reg(st, st->reg->int_enable,
+                                       INV_MPU6050_BIT_DATA_RDY_EN);
+               if (result)
+                       return result;
+       }
+       /* enable FIFO reading and I2C master interface*/
+       result = inv_mpu6050_write_reg(st, st->reg->user_ctrl,
+                                       INV_MPU6050_BIT_FIFO_EN);
+       if (result)
+               goto reset_fifo_fail;
+       /* enable sensor output to FIFO */
+       d = 0;
+       if (st->chip_config.gyro_fifo_enable)
+               d |= INV_MPU6050_BITS_GYRO_OUT;
+       if (st->chip_config.accl_fifo_enable)
+               d |= INV_MPU6050_BIT_ACCEL_OUT;
+       result = inv_mpu6050_write_reg(st, st->reg->fifo_en, d);
+       if (result)
+               goto reset_fifo_fail;
+
+       return 0;
+
+reset_fifo_fail:
+       dev_err(&st->client->dev, "reset fifo failed %d\n", result);
+       result = inv_mpu6050_write_reg(st, st->reg->int_enable,
+                                       INV_MPU6050_BIT_DATA_RDY_EN);
+
+       return result;
+}
+
+static void inv_clear_kfifo(struct inv_mpu6050_state *st)
+{
+       unsigned long flags;
+
+       /* take the spin lock sem to avoid interrupt kick in */
+       spin_lock_irqsave(&st->time_stamp_lock, flags);
+       kfifo_reset(&st->timestamps);
+       spin_unlock_irqrestore(&st->time_stamp_lock, flags);
+}
+
+/**
+ * inv_mpu6050_irq_handler() - Cache a timestamp at each data ready interrupt.
+ */
+irqreturn_t inv_mpu6050_irq_handler(int irq, void *p)
+{
+       struct iio_poll_func *pf = p;
+       struct iio_dev *indio_dev = pf->indio_dev;
+       struct inv_mpu6050_state *st = iio_priv(indio_dev);
+       s64 timestamp;
+
+       timestamp = iio_get_time_ns();
+       spin_lock(&st->time_stamp_lock);
+       kfifo_in(&st->timestamps, &timestamp, 1);
+       spin_unlock(&st->time_stamp_lock);
+
+       return IRQ_WAKE_THREAD;
+}
+
+/**
+ * inv_mpu6050_read_fifo() - Transfer data from hardware FIFO to KFIFO.
+ */
+irqreturn_t inv_mpu6050_read_fifo(int irq, void *p)
+{
+       struct iio_poll_func *pf = p;
+       struct iio_dev *indio_dev = pf->indio_dev;
+       struct inv_mpu6050_state *st = iio_priv(indio_dev);
+       size_t bytes_per_datum;
+       int result;
+       u8 data[INV_MPU6050_OUTPUT_DATA_SIZE];
+       u16 fifo_count;
+       s64 timestamp;
+       u64 *tmp;
+
+       mutex_lock(&indio_dev->mlock);
+       if (!(st->chip_config.accl_fifo_enable |
+               st->chip_config.gyro_fifo_enable))
+               goto end_session;
+       bytes_per_datum = 0;
+       if (st->chip_config.accl_fifo_enable)
+               bytes_per_datum += INV_MPU6050_BYTES_PER_3AXIS_SENSOR;
+
+       if (st->chip_config.gyro_fifo_enable)
+               bytes_per_datum += INV_MPU6050_BYTES_PER_3AXIS_SENSOR;
+
+       /*
+        * read fifo_count register to know how many bytes inside FIFO
+        * right now
+        */
+       result = i2c_smbus_read_i2c_block_data(st->client,
+                                      st->reg->fifo_count_h,
+                                      INV_MPU6050_FIFO_COUNT_BYTE, data);
+       if (result != INV_MPU6050_FIFO_COUNT_BYTE)
+               goto end_session;
+       fifo_count = be16_to_cpup((__be16 *)(&data[0]));
+       if (fifo_count < bytes_per_datum)
+               goto end_session;
+       /* fifo count can't be odd number, if it is odd, reset fifo*/
+       if (fifo_count & 1)
+               goto flush_fifo;
+       if (fifo_count >  INV_MPU6050_FIFO_THRESHOLD)
+               goto flush_fifo;
+       /* Timestamp mismatch. */
+       if (kfifo_len(&st->timestamps) >
+               fifo_count / bytes_per_datum + INV_MPU6050_TIME_STAMP_TOR)
+                       goto flush_fifo;
+       while (fifo_count >= bytes_per_datum) {
+               result = i2c_smbus_read_i2c_block_data(st->client,
+                                                      st->reg->fifo_r_w,
+                                                      bytes_per_datum, data);
+               if (result != bytes_per_datum)
+                       goto flush_fifo;
+
+               result = kfifo_out(&st->timestamps, &timestamp, 1);
+               /* when there is no timestamp, put timestamp as 0 */
+               if (0 == result)
+                       timestamp = 0;
+
+               tmp = (u64 *)data;
+               tmp[DIV_ROUND_UP(bytes_per_datum, 8)] = timestamp;
+               result = iio_push_to_buffers(indio_dev, data);
+               if (result)
+                       goto flush_fifo;
+               fifo_count -= bytes_per_datum;
+       }
+
+end_session:
+       mutex_unlock(&indio_dev->mlock);
+       iio_trigger_notify_done(indio_dev->trig);
+
+       return IRQ_HANDLED;
+
+flush_fifo:
+       /* Flush HW and SW FIFOs. */
+       inv_reset_fifo(indio_dev);
+       inv_clear_kfifo(st);
+       mutex_unlock(&indio_dev->mlock);
+       iio_trigger_notify_done(indio_dev->trig);
+
+       return IRQ_HANDLED;
+}
diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_trigger.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_trigger.c
new file mode 100644 (file)
index 0000000..e1d0869
--- /dev/null
@@ -0,0 +1,155 @@
+/*
+* Copyright (C) 2012 Invensense, Inc.
+*
+* This software is licensed under the terms of the GNU General Public
+* License version 2, as published by the Free Software Foundation, and
+* may be copied, distributed, and modified under those terms.
+*
+* 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 "inv_mpu_iio.h"
+
+static void inv_scan_query(struct iio_dev *indio_dev)
+{
+       struct inv_mpu6050_state  *st = iio_priv(indio_dev);
+
+       st->chip_config.gyro_fifo_enable =
+               test_bit(INV_MPU6050_SCAN_GYRO_X,
+                       indio_dev->active_scan_mask) ||
+                       test_bit(INV_MPU6050_SCAN_GYRO_Y,
+                       indio_dev->active_scan_mask) ||
+                       test_bit(INV_MPU6050_SCAN_GYRO_Z,
+                       indio_dev->active_scan_mask);
+
+       st->chip_config.accl_fifo_enable =
+               test_bit(INV_MPU6050_SCAN_ACCL_X,
+                       indio_dev->active_scan_mask) ||
+                       test_bit(INV_MPU6050_SCAN_ACCL_Y,
+                       indio_dev->active_scan_mask) ||
+                       test_bit(INV_MPU6050_SCAN_ACCL_Z,
+                       indio_dev->active_scan_mask);
+}
+
+/**
+ *  inv_mpu6050_set_enable() - enable chip functions.
+ *  @indio_dev:        Device driver instance.
+ *  @enable: enable/disable
+ */
+static int inv_mpu6050_set_enable(struct iio_dev *indio_dev, bool enable)
+{
+       struct inv_mpu6050_state *st = iio_priv(indio_dev);
+       int result;
+
+       if (enable) {
+               result = inv_mpu6050_set_power_itg(st, true);
+               if (result)
+                       return result;
+               inv_scan_query(indio_dev);
+               if (st->chip_config.gyro_fifo_enable) {
+                       result = inv_mpu6050_switch_engine(st, true,
+                                       INV_MPU6050_BIT_PWR_GYRO_STBY);
+                       if (result)
+                               return result;
+               }
+               if (st->chip_config.accl_fifo_enable) {
+                       result = inv_mpu6050_switch_engine(st, true,
+                                       INV_MPU6050_BIT_PWR_ACCL_STBY);
+                       if (result)
+                               return result;
+               }
+               result = inv_reset_fifo(indio_dev);
+               if (result)
+                       return result;
+       } else {
+               result = inv_mpu6050_write_reg(st, st->reg->fifo_en, 0);
+               if (result)
+                       return result;
+
+               result = inv_mpu6050_write_reg(st, st->reg->int_enable, 0);
+               if (result)
+                       return result;
+
+               result = inv_mpu6050_write_reg(st, st->reg->user_ctrl, 0);
+               if (result)
+                       return result;
+
+               result = inv_mpu6050_switch_engine(st, false,
+                                       INV_MPU6050_BIT_PWR_GYRO_STBY);
+               if (result)
+                       return result;
+
+               result = inv_mpu6050_switch_engine(st, false,
+                                       INV_MPU6050_BIT_PWR_ACCL_STBY);
+               if (result)
+                       return result;
+               result = inv_mpu6050_set_power_itg(st, false);
+               if (result)
+                       return result;
+       }
+       st->chip_config.enable = enable;
+
+       return 0;
+}
+
+/**
+ * inv_mpu_data_rdy_trigger_set_state() - set data ready interrupt state
+ * @trig: Trigger instance
+ * @state: Desired trigger state
+ */
+static int inv_mpu_data_rdy_trigger_set_state(struct iio_trigger *trig,
+                                               bool state)
+{
+       return inv_mpu6050_set_enable(trig->private_data, state);
+}
+
+static const struct iio_trigger_ops inv_mpu_trigger_ops = {
+       .owner = THIS_MODULE,
+       .set_trigger_state = &inv_mpu_data_rdy_trigger_set_state,
+};
+
+int inv_mpu6050_probe_trigger(struct iio_dev *indio_dev)
+{
+       int ret;
+       struct inv_mpu6050_state *st = iio_priv(indio_dev);
+
+       st->trig = iio_trigger_alloc("%s-dev%d",
+                                       indio_dev->name,
+                                       indio_dev->id);
+       if (st->trig == NULL) {
+               ret = -ENOMEM;
+               goto error_ret;
+       }
+       ret = request_irq(st->client->irq, &iio_trigger_generic_data_rdy_poll,
+                               IRQF_TRIGGER_RISING,
+                               "inv_mpu",
+                               st->trig);
+       if (ret)
+               goto error_free_trig;
+       st->trig->dev.parent = &st->client->dev;
+       st->trig->private_data = indio_dev;
+       st->trig->ops = &inv_mpu_trigger_ops;
+       ret = iio_trigger_register(st->trig);
+       if (ret)
+               goto error_free_irq;
+       indio_dev->trig = st->trig;
+
+       return 0;
+
+error_free_irq:
+       free_irq(st->client->irq, st->trig);
+error_free_trig:
+       iio_trigger_free(st->trig);
+error_ret:
+       return ret;
+}
+
+void inv_mpu6050_remove_trigger(struct inv_mpu6050_state *st)
+{
+       iio_trigger_unregister(st->trig);
+       free_irq(st->client->irq, st->trig);
+       iio_trigger_free(st->trig);
+}
diff --git a/include/linux/platform_data/invensense_mpu6050.h b/include/linux/platform_data/invensense_mpu6050.h
new file mode 100644 (file)
index 0000000..ad3aa7b
--- /dev/null
@@ -0,0 +1,31 @@
+/*
+* Copyright (C) 2012 Invensense, Inc.
+*
+* This software is licensed under the terms of the GNU General Public
+* License version 2, as published by the Free Software Foundation, and
+* may be copied, distributed, and modified under those terms.
+*
+* 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 __INV_MPU6050_PLATFORM_H_
+#define __INV_MPU6050_PLATFORM_H_
+
+/**
+ * struct inv_mpu6050_platform_data - Platform data for the mpu driver
+ * @orientation:       Orientation matrix of the chip
+ *
+ * Contains platform specific information on how to configure the MPU6050 to
+ * work on this platform.  The orientation matricies are 3x3 rotation matricies
+ * that are applied to the data to rotate from the mounting orientation to the
+ * platform orientation.  The values must be one of 0, 1, or -1 and each row and
+ * column should have exactly 1 non-zero value.
+ */
+struct inv_mpu6050_platform_data {
+       __s8 orientation[9];
+};
+
+#endif
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