> A few comments inline. This is a bit of a fiddly one isn't it ;)
some more comments on top
> > diff --git a/drivers/iio/gyro/Kconfig b/drivers/iio/gyro/Kconfig
> > index ac2d69e..d630ae9 100644
> > --- a/drivers/iio/gyro/Kconfig
> > +++ b/drivers/iio/gyro/Kconfig
> > @@ -50,6 +50,17 @@ config ADXRS450
> > This driver can also be built as a module. If so, the module
> > will be called adxrs450.
> >
> > +config BMG160
> > + tristate "BOSCH BMG160 Gyro Sensor"
> > + depends on I2C
> > + select IIO_TRIGGERED_BUFFER if IIO_BUFFER
> > + help
> > + Say yes here to build support for Bosch BMG160 Tri-axis Gyro Sensor
> > + driver.
> > +
> > + This driver can also be built as a module. If so, the module
> > + will be called bmg160.
> > +
> > config HID_SENSOR_GYRO_3D
> > depends on HID_SENSOR_HUB
> > select IIO_BUFFER
> > diff --git a/drivers/iio/gyro/Makefile b/drivers/iio/gyro/Makefile
> > index 2f2752a..36a3877 100644
> > --- a/drivers/iio/gyro/Makefile
> > +++ b/drivers/iio/gyro/Makefile
> > @@ -8,6 +8,7 @@ obj-$(CONFIG_ADIS16130) += adis16130.o
> > obj-$(CONFIG_ADIS16136) += adis16136.o
> > obj-$(CONFIG_ADIS16260) += adis16260.o
> > obj-$(CONFIG_ADXRS450) += adxrs450.o
> > +obj-$(CONFIG_BMG160) += bmg160.o
> >
> > obj-$(CONFIG_HID_SENSOR_GYRO_3D) += hid-sensor-gyro-3d.o
> >
> > diff --git a/drivers/iio/gyro/bmg160.c b/drivers/iio/gyro/bmg160.c
> > new file mode 100644
> > index 0000000..72381d0
> > --- /dev/null
> > +++ b/drivers/iio/gyro/bmg160.c
> > @@ -0,0 +1,984 @@
> > +/*
> > + * BMG160 Gyro Sensor driver
> > + * Copyright (c) 2014, Intel Corporation.
> > + *
> > + * This program is free software; you can redistribute it and/or modify it
> > + * under the terms and conditions of the GNU General Public License,
> > + * version 2, as published by the Free Software Foundation.
> > + *
> > + * This program is distributed in the hope 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/i2c.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/delay.h>
> > +#include <linux/slab.h>
> > +#include <linux/acpi.h>
> > +#include <linux/gpio/consumer.h>
> > +#include <linux/pm.h>
> > +#include <linux/pm_runtime.h>
> > +#include <linux/iio/iio.h>
> > +#include <linux/iio/sysfs.h>
> > +#include <linux/iio/buffer.h>
> > +#include <linux/iio/trigger.h>
> > +#include <linux/iio/events.h>
> > +#include <linux/iio/trigger_consumer.h>
> > +#include <linux/iio/triggered_buffer.h>
> > +
> > +#define BMG160_DRV_NAME "bmg160"
> > +#define BMG160_IRQ_NAME "bmg160_event"
> > +#define BMG160_GPIO_NAME "gpio_int"
> > +
> > +#define BMG160_REG_CHIP_ID 0x00
> > +#define BMG160_CHIP_ID_VAL 0x0F
> > +
> > +#define BMG160_REG_PMU_LPW 0x11
> > +#define BMG160_PMU_SLP_MASK 0xE0
> > +#define BMG160_PMU_SLP_SHIFT 5
> > +#define BMG160_PMU_BIT_SLEEP_DUR_MASK 0x17
> > +#define BMG160_PMU_BIT_SLEEP_DUR_SHIFT 1
> > +
> > +#define BMG160_REG_RANGE 0x0F
> > +
> > +#define BMG160_RANGE_2000DPS 0
> > +#define BMG160_RANGE_1000DPS 1
> > +#define BMG160_RANGE_500DPS 2
> > +#define BMG160_RANGE_250DPS 3
> > +#define BMG160_RANGE_125DPS 4
> > +
> > +#define BMG160_REG_PMU_BW 0x10
> > +#define BMG160_No_Filter 0
NO_FILTER
> > +#define BMG160_DEF_BW 100
> > +
> > +#define BMG160_REG_INT_MAP_0 0x17
> > +#define BMG160_INT_MAP_0_BIT_ANY BIT(1)
> > +
> > +#define BMG160_REG_INT_RST_LATCH 0x21
> > +#define BMG160_INT_MODE_LATCH_RESET 0x80
> > +#define BMG160_INT_MODE_LATCH_INT 0x0F
> > +
> > +#define BMG160_REG_INT_EN_0 0x15
> > +#define BMG160_DATA_ENABLE_INT BIT(7)
> > +
> > +#define BMG160_REG_XOUT_L 0x02
> > +#define BMG160_AXIS_TO_REG(axis) (BMG160_REG_XOUT_L + (axis * 2))
> > +
> > +#define BMG160_REG_SLOPE_THRES 0x1B
> > +#define BMG160_SLOPE_THRES_MASK 0x0F
> > +
> > +#define BMG160_REG_MOTION_INTR 0x1C
> > +#define BMG160_INT_MOTION_X BIT(0)
> > +#define BMG160_INT_MOTION_Y BIT(1)
> > +#define BMG160_INT_MOTION_Z BIT(2)
> > +#define BMG160_ANY_DUR_MASK 0x30
> > +#define BMG160_ANY_DUR_SHIFT 4
> > +/*
> > + * We are using Any-motion detection as described in section 4.8.5.
> > + * The min sample duration for rate comparison, This will reduce the
> > + * affective rate by this factor, so for user space notification, use
> > + * this factor, so setting 100HZ actually results notification of
> > + * 25HZ only. This chip doesn't allow going below this value.
> > + */
>
> Hmm. Doesn't this only apply to the events? The dataready signal will
> still tick along at full rate? If so have a primary sampling_frequency
> that is the full rate and an additional element for the events that
> is ready only and a 1/4 the value.
>
> > +#define BMG160_ANY_DUR_MIN_SAMPLE 4
> > +
> > +#define BMG160_MAX_STARTUP_TIME_MS 80
> > +
> > +#define BMG160_SLEEP_DELAY_MS 2000
> > +static int bmg160_power_off_delay_ms = BMG160_SLEEP_DELAY_MS;
> > +module_param(bmg160_power_off_delay_ms, int, 0644);
> > +MODULE_PARM_DESC(bmg160_power_off_delay_ms,
> > + "BMG160 Gyroscope power of delay in milli seconds.");
> Hmm. Does this make sense as a module parameter? What changes it?
> > +
> > +struct bmg160_data {
> > + struct i2c_client *client;
> > + struct iio_trigger *trig;
> > + struct mutex mutex;
> > + s16 buffer[12];
> I count 3 for the channels (pad to 4) and 4 for the timestamp.
> So a total buffer size of 8 not 12 (as in words)
> > + u8 bw_bits;
> > + u32 dps_range;
> > + int ev_enable_state;
ev_enable_state seems to be a bool
> > + int slope_thres;
> > + bool trigger_on;
> > +};
> > +
> > +enum bmg160_axis {
> > + AXIS_X,
> > + AXIS_Y,
> > + AXIS_Z,
> > +};
> > +
> > +enum bmg160_operation_mode {
> > + BMG160_MODE_NORMAL,
> > + BMG160_MODE_DEEP_SUSPEND,
> > + BMG160_MODE_SUSPEND,
> > +};
> > +
> > +static const struct {
> > + int val;
> > + int bw_bits;
bw_bits should be u8
> > +} bmg160_samp_freq_table[] = { {100, 0x07},
> > + {200, 0x06},
> > + {400, 0x03},
> > + {1000, 0x02},
> > + {2000, 0x01} };
> > +
> > +static const struct {
> > + int scale;
> > + int dps_range;
u8 dps_range
> > +} bmg160_scale_table[] = { { 1065, BMG160_RANGE_2000DPS},
> > + { 532, BMG160_RANGE_1000DPS},
> > + { 266, BMG160_RANGE_500DPS},
> > + { 133, BMG160_RANGE_250DPS},
> > + { 66, BMG160_RANGE_125DPS} };
> > +
> > +static int bmg160_set_mode(struct bmg160_data *data,
> > + enum bmg160_operation_mode mode)
> > +{
> > + int ret;
> > + u8 lpw_bits = 0;
> > +
> > + lpw_bits = mode << BMG160_PMU_SLP_SHIFT;
> > +
> > + dev_dbg(&data->client->dev, "Set Mode bits %x\n", lpw_bits);
> > +
> > + ret = i2c_smbus_write_byte_data(data->client,
> > + BMG160_REG_PMU_LPW, lpw_bits);
> > + if (ret < 0) {
> > + dev_err(&data->client->dev, "Error writing reg_pmu_lpw\n");
> > + return ret;
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static int bmg160_convert_freq_to_bit(int val)
> > +{
> > + int i;
> > +
> > + for (i = 0; i < ARRAY_SIZE(bmg160_samp_freq_table); ++i) {
> > + if (bmg160_samp_freq_table[i].val == val)
> > + return bmg160_samp_freq_table[i].bw_bits;
> > + }
> > +
> > + return -EINVAL;
> > +}
> > +
> > +static int bmg160_set_bw(struct bmg160_data *data, int val)
> > +{
> > + int ret;
> > + int bw_bits;
> > +
> > + bw_bits = bmg160_convert_freq_to_bit(val);
> > + if (bw_bits < 0)
> > + return bw_bits;
> > +
> > + ret = i2c_smbus_write_byte_data(data->client, BMG160_REG_PMU_BW,
> > + bw_bits);
> > + if (ret < 0) {
> > + dev_err(&data->client->dev, "Error writing pmu_bw\n");
the error messages are inconsistent, I'd expect reg_pmu_bw here
> > + return ret;
> > + }
> > +
> > + data->bw_bits = bw_bits;
> > +
> > + return 0;
> > +}
> > +
> > +static int bmg160_chip_init(struct bmg160_data *data)
> > +{
> > + int ret;
> > +
> > + ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_CHIP_ID);
> > + if (ret < 0) {
> > + dev_err(&data->client->dev,
> > + "Error:BMG160_REG_CHIP_ID\n");
"Error reading reg_chip_id"
> > + return ret;
> > + }
> > +
> > + dev_dbg(&data->client->dev, "Chip Id %x\n", ret);
> > + if (ret != BMG160_CHIP_ID_VAL) {
> > + dev_err(&data->client->dev, "invalid chip %x\n", ret);
> > + return -ENODEV;
> > + }
> > +
> > + /* Set Bandwidth */
> > + ret = bmg160_set_bw(data, BMG160_DEF_BW);
> > + if (ret < 0)
> > + return ret;
> > +
> > + /* Set Default Range */
> > + ret = i2c_smbus_write_byte_data(data->client,
> > + BMG160_REG_RANGE,
> > + BMG160_RANGE_500DPS);
> > + if (ret < 0) {
> > + dev_err(&data->client->dev,
> > + "Error writing pmu_dps_range\n");
register is called reg_range
> > + return ret;
> > + }
> > + data->dps_range = BMG160_RANGE_500DPS;
> > +
> > + ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_SLOPE_THRES);
> > + if (ret < 0) {
> > + dev_err(&data->client->dev, "Error: reading slope_thres\n");
> > + return ret;
> > + }
> > + data->slope_thres = ret;
> > +
> > + return bmg160_set_mode(data, BMG160_MODE_SUSPEND);
> > +}
> > +
> > +static int bmg160_set_power_state(struct bmg160_data *data, bool on)
> > +{
> > + int ret;
> > +
> > +#ifdef CONFIG_PM_RUNTIME
> > + if (on)
> > + ret = pm_runtime_get_sync(&data->client->dev);
> > + else {
> > + pm_runtime_put_noidle(&data->client->dev);
> > + ret = pm_schedule_suspend(&data->client->dev,
> > + bmg160_power_off_delay_ms);
> > + }
> > +#else
> > + if (on) {
> > + ret = bmg160_set_mode(data, BMG160_MODE_NORMAL);
> > + if (!ret)
> > + msleep_interruptible(BMG160_MAX_STARTUP_TIME_MS);
> > + } else
> > + ret = bmg160_set_mode(data, BMG160_MODE_SUSPEND);
> > +#endif
> > +
> > + if (ret < 0) {
> > + dev_err(&data->client->dev,
> > + "Failed: bmg160_set_power_state for %d\n", on);
> > + return ret;
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static int bmg160_chip_setup_interrupt(struct bmg160_data *data, bool
> > status)
> > +{
> > + int ret;
> > +
> > + /* Enable/Disable INT1 mapping */
> > + ret = i2c_smbus_read_byte_data(data->client,
> > + BMG160_REG_INT_MAP_0);
> > + if (ret < 0) {
> > + dev_err(&data->client->dev, "Error read reg_int_map0\n");
reading
> > + return ret;
> > + }
> > + if (status)
> > + ret |= BMG160_INT_MAP_0_BIT_ANY;
> > + else
> > + ret &= ~BMG160_INT_MAP_0_BIT_ANY;
> > +
> > + ret = i2c_smbus_write_byte_data(data->client,
> > + BMG160_REG_INT_MAP_0,
> > + ret);
> > + if (ret < 0) {
> > + dev_err(&data->client->dev, "Error write reg_int_map0\n");
> > + return ret;
> > + }
> > +
> > + /* Set latched mode interrupt and clear any latched interrupt */
> > + ret = i2c_smbus_write_byte_data(data->client,
> > + BMG160_REG_INT_RST_LATCH,
> > + BMG160_INT_MODE_LATCH_INT |
> > + BMG160_INT_MODE_LATCH_RESET);
> > + if (ret < 0) {
> > + dev_err(&data->client->dev, "Error write reg_rst_latch\n");
writing (I'll stop this kind of nitpicking here :)
> > + return ret;
> > + }
> > +
> > + /* Enable/Disable slope interrupts */
> > + if (status) {
> > +
> > + /* Update slope thres */
> > + ret = i2c_smbus_write_byte_data(data->client,
> > + BMG160_REG_SLOPE_THRES,
> > + data->slope_thres);
> > + if (ret < 0) {
> > + dev_err(&data->client->dev,
> > + "Error write reg_slope_thres\n");
> > + return ret;
> > + }
> > +
> > + ret = i2c_smbus_write_byte_data(data->client,
> > + BMG160_REG_MOTION_INTR,
> > + BMG160_INT_MOTION_X |
> > + BMG160_INT_MOTION_Y |
> > + BMG160_INT_MOTION_Z);
> > + if (ret < 0) {
> > + dev_err(&data->client->dev,
> > + "Error write reg_motion_intr\n");
> > + return ret;
> > + }
> > +
> > + ret = i2c_smbus_write_byte_data(data->client,
> > + BMG160_REG_INT_EN_0,
> > + BMG160_DATA_ENABLE_INT);
> > + } else
> > + ret = i2c_smbus_write_byte_data(data->client,
> > + BMG160_REG_INT_EN_0,
> > + 0);
> > +
> > + if (ret < 0) {
> > + dev_err(&data->client->dev, "Error writing reg_int_en0\n");
> > + return ret;
> > + }
> > +
> > + return ret;
> > +}
> > +
> > +static int bmg160_get_bw(struct bmg160_data *data, int *val)
> > +{
> > + int i;
> > +
> > + for (i = 0; i < ARRAY_SIZE(bmg160_samp_freq_table); ++i) {
> > + if (bmg160_samp_freq_table[i].bw_bits == data->bw_bits) {
> > + *val = bmg160_samp_freq_table[i].val;
> > + return IIO_VAL_INT;
> > + }
> > + }
> > +
> > + return -EINVAL;
> > +}
> > +
> > +static int bmg160_set_scale(struct bmg160_data *data, int val)
> > +{
> > + int ret, i;
> > +
> > + for (i = 0; i < ARRAY_SIZE(bmg160_scale_table); ++i) {
> > + if (bmg160_scale_table[i].scale == val) {
> > + ret = i2c_smbus_write_byte_data(
> > + data->client,
> > + BMG160_REG_RANGE,
> > + bmg160_scale_table[i].dps_range);
> > + if (ret < 0) {
> > + dev_err(&data->client->dev,
> > + "Error writing pmu_dps_range\n");
> > + return ret;
> > + }
> > + data->dps_range = bmg160_scale_table[i].dps_range;
> > + return 0;
> > + }
> > + }
> > +
> > + return -EINVAL;
> > +}
> > +
> > +static int bmg160_read_raw(struct iio_dev *indio_dev,
> > + struct iio_chan_spec const *chan,
> > + int *val, int *val2, long mask)
> > +{
> > + struct bmg160_data *data = iio_priv(indio_dev);
> > + int ret;
> > +
> > + switch (mask) {
> > + case IIO_CHAN_INFO_RAW:
> > + mutex_lock(&data->mutex);
> > + if (iio_buffer_enabled(indio_dev))
> > + ret = -EBUSY;
> > + else {
> > + ret = bmg160_set_power_state(data, true);
> > + if (ret < 0) {
> > + mutex_unlock(&data->mutex);
> > + return ret;
> > + }
> > + ret = i2c_smbus_read_word_data(data->client,
> > + BMG160_AXIS_TO_REG(
> > + chan->scan_index));
> > + if (ret < 0) {
> > + bmg160_set_power_state(data, false);
> > + mutex_unlock(&data->mutex);
> > + return ret;
> > + }
> > + *val = sign_extend32(ret, 15);
> > + ret = bmg160_set_power_state(data, false);
> > + }
> > + mutex_unlock(&data->mutex);
> > +
> > + if (ret < 0)
> > + return ret;
> > +
> > + return IIO_VAL_INT;
> > + case IIO_CHAN_INFO_SCALE:
> > + *val = 0;
> > + switch (data->dps_range) {
do a lookup in bmg160_scale_table which stores this mapping already?
> > + case BMG160_RANGE_2000DPS:
> > + *val2 = 1065;
> > + break;
> > + case BMG160_RANGE_1000DPS:
> > + *val2 = 532;
> > + break;
> > + case BMG160_RANGE_500DPS:
> > + *val2 = 266;
> > + break;
> > + case BMG160_RANGE_250DPS:
> > + *val2 = 133;
> > + break;
> > + case BMG160_RANGE_125DPS:
> > + *val2 = 66;
> > + break;
> > + default:
> > + return -EINVAL;
> > + }
> > + return IIO_VAL_INT_PLUS_MICRO;
> > + case IIO_CHAN_INFO_SAMP_FREQ:
> > + *val2 = 0;
> > + mutex_lock(&data->mutex);
> > + ret = bmg160_get_bw(data, val);
> > + if (ret == IIO_VAL_INT)
> > + *val /= BMG160_ANY_DUR_MIN_SAMPLE;
> > + mutex_unlock(&data->mutex);
> > + return ret;
> > + default:
> > + return -EINVAL;
> > + }
> > +}
> > +
> > +static int bmg160_write_raw(struct iio_dev *indio_dev,
> > + struct iio_chan_spec const *chan,
> > + int val, int val2, long mask)
> > +{
> > + struct bmg160_data *data = iio_priv(indio_dev);
> > + int ret;
> > +
> > + switch (mask) {
> > + case IIO_CHAN_INFO_SAMP_FREQ:
> > + mutex_lock(&data->mutex);
> > + ret = bmg160_set_bw(data, val * BMG160_ANY_DUR_MIN_SAMPLE);
> > + mutex_unlock(&data->mutex);
return ret;
> > + break;
> > + case IIO_CHAN_INFO_SCALE:
> > + if (val)
> > + return -EINVAL;
> > + mutex_lock(&data->mutex);
> > + ret = bmg160_set_scale(data, val2);
> > + mutex_unlock(&data->mutex);
> > + return ret;
> > + default:
> > + ret = -EINVAL;
return -EINVAL;
> > + }
> > +
> > + return ret;
remove line above
> > +}
> > +
> > +static int bmg160_read_event(struct iio_dev *indio_dev,
> > + const struct iio_chan_spec *chan,
> > + enum iio_event_type type,
> > + enum iio_event_direction dir,
> > + enum iio_event_info info,
> > + int *val, int *val2)
> > +{
> > + struct bmg160_data *data = iio_priv(indio_dev);
> > +
> > + *val2 = 0;
> > + switch (info) {
> > + case IIO_EV_INFO_VALUE:
> > + *val = data->slope_thres & BMG160_SLOPE_THRES_MASK;
> > + break;
> > + default:
> > + return -EINVAL;
> > + }
> > +
> > + return IIO_VAL_INT;
> > +}
> > +
> > +static int bmg160_write_event(struct iio_dev *indio_dev,
> > + const struct iio_chan_spec *chan,
> > + enum iio_event_type type,
> > + enum iio_event_direction dir,
> > + enum iio_event_info info,
> > + int val, int val2)
> > +{
> > + struct bmg160_data *data = iio_priv(indio_dev);
> > +
> > + switch (info) {
> > + case IIO_EV_INFO_VALUE:
> > + data->slope_thres &= ~BMG160_SLOPE_THRES_MASK;
> > + data->slope_thres |= (val & BMG160_SLOPE_THRES_MASK);
> > + break;
> > + default:
> > + return -EINVAL;
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static int bmg160_read_event_config(struct iio_dev *indio_dev,
> > + const struct iio_chan_spec *chan,
> > + enum iio_event_type type,
> > + enum iio_event_direction dir)
> > +{
> > +
> > + struct bmg160_data *data = iio_priv(indio_dev);
> > +
> > + return data->ev_enable_state;
> > +}
> > +
> > +static int bmg160_write_event_config(struct iio_dev *indio_dev,
> > + const struct iio_chan_spec *chan,
> > + enum iio_event_type type,
> > + enum iio_event_direction dir,
> > + int state)
> > +{
> > + struct bmg160_data *data = iio_priv(indio_dev);
> > + int ret;
> > +
> > + if (data->trigger_on)
> > + return -EAGAIN;
> > +
> > + if (state && data->ev_enable_state)
> > + return 0;
> > +
> > + mutex_lock(&data->mutex);
> > + ret = bmg160_chip_setup_interrupt(data, state);
> > + if (!ret) {
> > + ret = bmg160_set_power_state(data, state);
> > + if (ret < 0) {
> > + mutex_unlock(&data->mutex);
> > + return ret;
> > + }
> > + }
> > + data->ev_enable_state = state;
> > + mutex_unlock(&data->mutex);
> > +
> > + return 0;
> > +}
> > +
> > +static int bmc150_validate_trigger(struct iio_dev *indio_dev,
> > + struct iio_trigger *trig)
prefix should be bmg160, not bmc150
> > +{
> > + struct bmg160_data *data = iio_priv(indio_dev);
> > +
> > + if (data->trig != trig)
> > + return -EINVAL;
> > +
> > + return 0;
> > +}
> > +
> > +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
> > + "25.0 50.0 100.0 250.0 500.0");
> You don't need the .0's though I don't suppose it does any harm!
> > +
> > +static IIO_CONST_ATTR(in_anglvel_scale_available,
> > + "0.001065 0.000532 0.000133 0.000066");
> > +
> > +static struct attribute *bmg160_attributes[] = {
> > + &iio_const_attr_sampling_frequency_available.dev_attr.attr,
> > + &iio_const_attr_in_anglvel_scale_available.dev_attr.attr,
> > + NULL,
> > +};
> > +
> > +static const struct attribute_group bmg160_attrs_group = {
> > + .attrs = bmg160_attributes,
> > +};
> > +
> > +static const struct iio_event_spec bmg160_event = {
> > + .type = IIO_EV_TYPE_ROC,
> > + .dir = IIO_EV_DIR_EITHER,
> > + .mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
> > + BIT(IIO_EV_INFO_ENABLE)
> > +};
> > +
> > +#define BMG160_CHANNEL(_axis) {
> > \
> > + .type = IIO_ANGL_VEL, \
> > + .modified = 1, \
> > + .channel2 = IIO_MOD_##_axis, \
> > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
> > + BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> > + .scan_index = AXIS_##_axis, \
> > + .scan_type = { \
> > + .sign = 's', \
> > + .realbits = 16, \
> > + .storagebits = 16, \
> I'd not bother specifying shift as it will default to zero anyway.
> > + .shift = 0, \
> > + }, \
> > + .event_spec = &bmg160_event, \
> > + .num_event_specs = 1 \
> > +}
> > +
> > +static const struct iio_chan_spec bmg160_channels[] = {
> > + BMG160_CHANNEL(X),
> > + BMG160_CHANNEL(Y),
> > + BMG160_CHANNEL(Z),
> Isn't there a temp sensor? Add it as non buffered (scan_index = -1)
> > + IIO_CHAN_SOFT_TIMESTAMP(3),
> > +};
> > +
> > +static const struct iio_info bmg160_info = {
> > + .attrs = &bmg160_attrs_group,
> > + .read_raw = bmg160_read_raw,
> > + .write_raw = bmg160_write_raw,
> > + .read_event_value = bmg160_read_event,
> > + .write_event_value = bmg160_write_event,
> > + .write_event_config = bmg160_write_event_config,
> > + .read_event_config = bmg160_read_event_config,
> > + .validate_trigger = bmc150_validate_trigger,
> > + .driver_module = THIS_MODULE,
> > +};
> > +
> > +static irqreturn_t bmg160_trigger_handler(int irq, void *p)
> > +{
> > + struct iio_poll_func *pf = p;
> > + struct iio_dev *indio_dev = pf->indio_dev;
> > + struct bmg160_data *data = iio_priv(indio_dev);
> > + int bit, ret, i = 0;
> > +
> > + mutex_lock(&data->mutex);
> > + for_each_set_bit(bit, indio_dev->buffer->scan_mask,
> > + indio_dev->masklength) {
> > + ret = i2c_smbus_read_word_data(data->client,
> > + BMG160_AXIS_TO_REG(bit));
> > + if (ret < 0) {
> > + mutex_unlock(&data->mutex);
> > + goto err;
> > + }
> > + data->buffer[i++] = ret;
> > + }
> > + mutex_unlock(&data->mutex);
> > +
> > + iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
> > + pf->timestamp);
> > +err:
> > + iio_trigger_notify_done(indio_dev->trig);
> > +
> > + return IRQ_HANDLED;
> > +}
> > +
> > +static int bmg160_trig_try_reen(struct iio_trigger *trig)
> > +{
> > + struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
> > + struct bmg160_data *data = iio_priv(indio_dev);
> > + int ret;
> > +
> > + /* Set latched mode interrupt and clear any latched interrupt */
> > + ret = i2c_smbus_write_byte_data(data->client,
> > + BMG160_REG_INT_RST_LATCH,
> > + BMG160_INT_MODE_LATCH_INT |
> > + BMG160_INT_MODE_LATCH_RESET);
> > + if (ret < 0) {
> > + dev_err(&data->client->dev, "Error writing reg_rst_latch\n");
> > + return ret;
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static int bmg160_data_rdy_trigger_set_state(struct iio_trigger *trig,
> > + bool state)
> > +{
> > + struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
> > + struct bmg160_data *data = iio_priv(indio_dev);
> > + int ret;
> > +
> > + if (data->ev_enable_state)
> > + return -EAGAIN;
> > +
> > + if (state && data->trigger_on)
> > + return 0;
> > +
> > + mutex_lock(&data->mutex);
> > + ret = bmg160_chip_setup_interrupt(data, state);
> > + if (!ret) {
> > + ret = bmg160_set_power_state(data, state);
> > + if (ret < 0) {
> > + mutex_unlock(&data->mutex);
> > + return ret;
> > + }
> > + }
> > + data->trigger_on = state;
> > + mutex_unlock(&data->mutex);
> > +
> > + return 0;
> > +}
> > +
> > +static const struct iio_trigger_ops bmg160_trigger_ops = {
> > + .set_trigger_state = bmg160_data_rdy_trigger_set_state,
> > + .try_reenable = bmg160_trig_try_reen,
> > + .owner = THIS_MODULE,
> > +};
> > +
> > +static irqreturn_t bmg160_event_handler(int irq, void *private)
> > +{
> > + struct iio_dev *indio_dev = private;
> > + struct bmg160_data *data = iio_priv(indio_dev);
> > + int ret;
> > +
> To my read we have two possible events. An any motion and a high rate.
> This is the any motion? I guess it is ROC change. The direction bit
> isn't for this purpose. It is intended for events that fire an interrupt
> when a threshold is crossed in any direction. Here you actually have
> a rising rate of change (though I'm not sure we have it definited clearly
> as being unsigned...) Might need some clarification of a distinction between
> IIO_EV_TYPE_ROC and say IIO_EV_TYPE_MAG_ROC.
>
> Whilst not strictly necessary I'd also read the status to confirm that it
> was this event. I think you can also confirm the axis (or first one to
> trigger which isn't ideal).
>
> The other event type is going to be more 'interesting' to add!
>
> > + iio_push_event(indio_dev, IIO_MOD_EVENT_CODE(IIO_ANGL_VEL,
> > + 0,
> > + IIO_MOD_X_OR_Y_OR_Z,
> > + IIO_EV_TYPE_ROC,
> > + IIO_EV_DIR_EITHER),
> > + iio_get_time_ns());
> > +
> > + ret = i2c_smbus_write_byte_data(data->client,
> > + BMG160_REG_INT_RST_LATCH,
> > + BMG160_INT_MODE_LATCH_INT |
> > + BMG160_INT_MODE_LATCH_RESET);
> > + if (ret < 0)
> > + dev_err(&data->client->dev, "Error writing reg_rst_latch\n");
> > +
> > + return IRQ_HANDLED;
> > +}
> > +
> > +static irqreturn_t bmg160_data_rdy_trig_poll(int irq, void *private)
> > +{
> > + struct iio_dev *indio_dev = private;
> > + struct bmg160_data *data = iio_priv(indio_dev);
> > +
> > + if (data->trigger_on) {
> > + iio_trigger_poll(data->trig);
> > + return IRQ_HANDLED;
> > + } else
> > + return IRQ_WAKE_THREAD;
> From my quick glance at the datasheet it's perfectly possible to have
> both data ready and events on the same interrupt pin. Here you prevent
> this.
>
> I presume that this is to avoid limiting the dataready trigger to only the
> chained form? (e.g. bottom half only). The complexity being that if you do
> that you'll both limit the use of the trigger and make it trickier to get
> the time stamp (you'll need to roll your own save of it here).
>
> Admitedly any sane implementation of this (to my mind) that wants both
> fast data capture and events should be using the pair of interrupt pins ;)
> > +}
> > +
> > +static int bmg160_acpi_gpio_probe(struct i2c_client *client,
> > + struct bmg160_data *data)
> > +{
> > + const struct acpi_device_id *id;
> > + struct device *dev;
> > + struct gpio_desc *gpio;
> > + int ret;
> > +
> > + if (!client)
> > + return -EINVAL;
> > +
> > + dev = &client->dev;
> > + if (!ACPI_HANDLE(dev))
> > + return -ENODEV;
> > +
> > + id = acpi_match_device(dev->driver->acpi_match_table, dev);
> > + if (!id)
> > + return -ENODEV;
> > +
> > + /* data ready gpio interrupt pin */
> > + gpio = devm_gpiod_get_index(dev, BMG160_GPIO_NAME, 0);
> > + if (IS_ERR(gpio)) {
> > + dev_err(dev, "acpi gpio get index failed\n");
> > + return PTR_ERR(gpio);
> > + }
> > +
> > + ret = gpiod_direction_input(gpio);
> > + if (ret)
> > + return ret;
> > +
> > + ret = gpiod_to_irq(gpio);
> > +
> > + dev_dbg(dev, "GPIO resource, no:%d irq:%d\n", desc_to_gpio(gpio),
> > ret);
> > +
> > + return ret;
> > +}
> > +
> > +static int bmg160_probe(struct i2c_client *client,
> > + const struct i2c_device_id *id)
> > +{
> > + struct bmg160_data *data;
> > + struct iio_dev *indio_dev;
> > + struct iio_trigger *trig = NULL;
> Why the intialization? Doesn't appear necessary.
> > + int ret;
> > +
> > + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> > + if (!indio_dev)
> > + return -ENOMEM;
> > +
> > + data = iio_priv(indio_dev);
> > + i2c_set_clientdata(client, indio_dev);
> > + data->client = client;
> > +
> > + ret = bmg160_chip_init(data);
> > + if (ret < 0)
> > + return ret;
> > +
> > + mutex_init(&data->mutex);
> > +
> > + indio_dev->dev.parent = &client->dev;
> > + indio_dev->channels = bmg160_channels;
> > + indio_dev->num_channels = ARRAY_SIZE(bmg160_channels);
> > + indio_dev->name = BMG160_DRV_NAME;
> > + indio_dev->modes = INDIO_DIRECT_MODE;
> > + indio_dev->info = &bmg160_info;
> > +
> > + if (client->irq <= 0)
> > + client->irq = bmg160_acpi_gpio_probe(client, data);
> > +
> > + if (client->irq > 0) {
> interesting. So the top half id doing the dataready but only launches
> the bottom half if not firing the trigger irq chip. I suppose that
> should work cleanly.
> > + ret = devm_request_threaded_irq(
> > + &client->dev, client->irq,
> > + bmg160_data_rdy_trig_poll,
> > + bmg160_event_handler,
> > + IRQF_TRIGGER_RISING,
> > + BMG160_IRQ_NAME,
> > + indio_dev);
> > + if (ret)
> > + return ret;
> > +
> > + trig = iio_trigger_alloc("%s-dev%d", indio_dev->name,
> > + indio_dev->id);
> > + if (!trig)
> > + return -ENOMEM;
> > +
> > + trig->dev.parent = &client->dev;
> > + trig->ops = &bmg160_trigger_ops;
> > + iio_trigger_set_drvdata(trig, indio_dev);
> > + data->trig = trig;
> > +
> > + ret = iio_trigger_register(trig);
> > + if (ret)
> > + goto err_trigger_free;
> > +
> > + ret = iio_triggered_buffer_setup(indio_dev,
> > + &iio_pollfunc_store_time,
> > + bmg160_trigger_handler,
> > + NULL);
> > + if (ret < 0) {
> > + dev_err(&client->dev,
> > + "iio triggered buffer setup failed\n");
> > + goto err_trigger_unregister;
> > + }
> > + }
> > +
> > + ret = iio_device_register(indio_dev);
> > + if (ret < 0) {
> > + dev_err(&client->dev, "unable to register iio device\n");
> > + goto err_buffer_cleanup;
> > + }
> > + ret = pm_runtime_set_active(&client->dev);
> > + if (ret)
> > + goto err_iio_unregister;
> > +
> > + pm_runtime_enable(&client->dev);
> > +
> > + return 0;
> > +
> > +err_iio_unregister:
> > + iio_device_unregister(indio_dev);
> > +err_buffer_cleanup:
> > + if (data->trig)
> > + iio_triggered_buffer_cleanup(indio_dev);
> > +err_trigger_unregister:
> > + if (data->trig)
> > + iio_trigger_unregister(trig);
> > +err_trigger_free:
> > + if (data->trig)
> > + iio_trigger_free(trig);
> > +
> > + return ret;
> > +}
> > +
> > +static int bmg160_remove(struct i2c_client *client)
> > +{
> > + struct iio_dev *indio_dev = i2c_get_clientdata(client);
> > + struct bmg160_data *data = iio_priv(indio_dev);
> > +
> > + pm_runtime_disable(&client->dev);
> > + pm_runtime_set_suspended(&client->dev);
> > + pm_runtime_put_noidle(&client->dev);
> I'm not at all familiar with the runtime PM stuff and their documentation
> doesn't exactlly make it obvious what fits where! Hence if anyone else
> wants to take a deep dive in and comment on this I'd be most happy.
> > +
> > + iio_device_unregister(indio_dev);
> > +
> > + if (data->trig) {
> > + iio_triggered_buffer_cleanup(indio_dev);
> > + iio_trigger_unregister(data->trig);
> It won't make a huge amount of difference but is there any disadvantage
> in using the devm_iio_trigger_alloc call and dropping the frees?
> > + iio_trigger_free(data->trig);
> > + }
> > +
> > + mutex_lock(&data->mutex);
> > + bmg160_set_mode(data, BMG160_MODE_DEEP_SUSPEND);
> > + mutex_unlock(&data->mutex);
> > +
> > + return 0;
> > +}
> > +
> > +#ifdef CONFIG_PM_SLEEP
> > +static int bmg160_suspend(struct device *dev)
> > +{
> > + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
> > + struct bmg160_data *data = iio_priv(indio_dev);
> > +
> > + mutex_lock(&data->mutex);
> > + bmg160_set_mode(data, BMG160_MODE_SUSPEND);
> > + mutex_unlock(&data->mutex);
> > +
> > + return 0;
> > +}
> > +
> > +static int bmg160_resume(struct device *dev)
> > +{
> > + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
> > + struct bmg160_data *data = iio_priv(indio_dev);
> > +
> > + mutex_lock(&data->mutex);
> > + if (data->trigger_on || data->ev_enable_state)
> > + bmg160_set_mode(data, BMG160_MODE_NORMAL);
> > + mutex_unlock(&data->mutex);
> > +
> > + return 0;
> > +}
> > +#endif
> > +
> > +#ifdef CONFIG_PM_RUNTIME
> > +static int bmg160_runtime_suspend(struct device *dev)
> > +{
> Given the only difference between the runtime and normal versions is
> the locking, perhaps it makes sense to merge the code into a utility function?
> Might not be worth the hassel though.
>
> > + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
> > + struct bmg160_data *data = iio_priv(indio_dev);
> > +
> > + return bmg160_set_mode(data, BMG160_MODE_SUSPEND);
> > +}
> > +
> > +static int bmg160_runtime_resume(struct device *dev)
> > +{
> > + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
> > + struct bmg160_data *data = iio_priv(indio_dev);
> > + int ret;
> > +
> > + ret = bmg160_set_mode(data, BMG160_MODE_NORMAL);
> > + if (ret < 0)
> > + return ret;
> > +
> > + msleep_interruptible(BMG160_MAX_STARTUP_TIME_MS);
> > +
> > + return 0;
> > +}
> > +#endif
> > +
> > +static const struct dev_pm_ops bmg160_pm_ops = {
> > + SET_SYSTEM_SLEEP_PM_OPS(bmg160_suspend, bmg160_resume)
> > + SET_RUNTIME_PM_OPS(bmg160_runtime_suspend,
> > + bmg160_runtime_resume, NULL)
> > +};
> > +
> > +static const struct acpi_device_id bmg160_acpi_match[] = {
> > + {"BMG0160", 0},
> > + { },
> > +};
> > +MODULE_DEVICE_TABLE(acpi, bmg160_acpi_match);
> > +
> > +static const struct i2c_device_id bmg160_id[] = {
> > + {"bmg160", 0},
> > + {}
> > +};
> > +
> > +MODULE_DEVICE_TABLE(i2c, bmg160_id);
> > +
> > +static struct i2c_driver bmg160_driver = {
> > + .driver = {
> > + .name = BMG160_DRV_NAME,
> > + .acpi_match_table = ACPI_PTR(bmg160_acpi_match),
> > + .pm = &bmg160_pm_ops,
> > + },
> > + .probe = bmg160_probe,
> > + .remove = bmg160_remove,
> > + .id_table = bmg160_id,
> > +};
> > +module_i2c_driver(bmg160_driver);
> > +
> > +MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>");
> > +MODULE_LICENSE("GPL v2");
> > +MODULE_DESCRIPTION("BMG160 Gyro driver");
> >
>
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--
Peter Meerwald
+43-664-2444418 (mobile)
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