Re: [PATCH v3 1/2] iio:gyro:bmg160 Gyro Sensor driver

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




On 08/07/2014 03:39 AM, Jonathan Cameron wrote:
On 05/08/14 22:57, Srinivas Pandruvada wrote:
This change implements support for BMG160 Gyro sensor. Although chip
has several advanced features, this change implements minimum set
required for using gyro sensor.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
One more query.  In the write_raw function you always enable then suspend the
device.  The enable is safe, but if you have a write to the attributes
whilst operating in triggered / buffered mode will it not disable the
device?  It is perfectly permissible to ignore such a write (return -EBUSY)
but I don't think you are doing so.
I will check on this.

Thanks,
Srinivas

Otherwise, looks good to me.  Nice explanatory comments as well!
---
  drivers/iio/gyro/Kconfig  |   11 +
  drivers/iio/gyro/Makefile |    1 +
  drivers/iio/gyro/bmg160.c | 1211 +++++++++++++++++++++++++++++++++++++++++++++
  3 files changed, 1223 insertions(+)
  create mode 100644 drivers/iio/gyro/bmg160.c

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..80f92a6
--- /dev/null
+++ b/drivers/iio/gyro/bmg160.c
@@ -0,0 +1,1211 @@
+/*
+ * 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_MODE_NORMAL		0x00
+#define BMG160_MODE_DEEP_SUSPEND	0x20
+#define BMG160_MODE_SUSPEND		0x80
+
+#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
+#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_MAP_1		0x18
+#define BMG160_INT_MAP_1_BIT_NEW_DATA	BIT(0)
+
+#define BMG160_REG_INT_RST_LATCH	0x21
+#define BMG160_INT_MODE_LATCH_RESET	0x80
+#define BMG160_INT_MODE_LATCH_INT	0x0F
+#define BMG160_INT_MODE_NON_LATCH_INT	0x00
+
+#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
+
+#define BMG160_REG_INT_STATUS_2	0x0B
+#define BMG160_ANY_MOTION_MASK		0x07
+
+#define BMG160_REG_TEMP		0x08
+#define BMG160_TEMP_CENTER_VAL		23
+
+#define BMG160_MAX_STARTUP_TIME_MS	80
+
+#define BMG160_AUTO_SUSPEND_DELAY_MS	2000
+
+struct bmg160_data {
+	struct i2c_client *client;
+	struct iio_trigger *dready_trig;
+	struct iio_trigger *motion_trig;
+	struct mutex mutex;
+	s16 buffer[8];
+	u8 bw_bits;
+	u32 dps_range;
+	int ev_enable_state;
+	int slope_thres;
+	bool dready_trigger_on;
+	bool motion_trigger_on;
+	int64_t timestamp;
+};
+
+enum bmg160_axis {
+	AXIS_X,
+	AXIS_Y,
+	AXIS_Z,
+};
+
+static const struct {
+	int val;
+	int bw_bits;
+} bmg160_samp_freq_table[] = { {100, 0x07},
+			       {200, 0x06},
+			       {400, 0x03},
+			       {1000, 0x02},
+			       {2000, 0x01} };
+
+static const struct {
+	int scale;
+	int 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, u8 mode)
+{
+	int ret;
+
+	ret = i2c_smbus_write_byte_data(data->client,
+					BMG160_REG_PMU_LPW, mode);
+	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 reg_pmu_bw\n");
+		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 reading reg_chip_id\n");
+		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;
+	}
+
+	ret = bmg160_set_mode(data, BMG160_MODE_NORMAL);
+	if (ret < 0)
+		return ret;
+
+	/* Wait upto 500 ms to be ready after changing mode */
+	usleep_range(500, 1000);
+
+	/* 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 reg_range\n");
+		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 reg_slope_thres\n");
+		return ret;
+	}
+	data->slope_thres = ret;
+
+	/* Set default interrupt mode */
+	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_motion_intr\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int bmg160_set_power_state(struct bmg160_data *data, bool on)
+{
+	int ret;
+
+	if (on)
+		ret = pm_runtime_get_sync(&data->client->dev);
+	else {
+		pm_runtime_mark_last_busy(&data->client->dev);
+		ret = pm_runtime_put_autosuspend(&data->client->dev);
+	}
+
+	if (ret < 0) {
+		dev_err(&data->client->dev,
+			"Failed: bmg160_set_power_state for %d\n", on);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int bmg160_setup_any_motion_interrupt(struct bmg160_data *data,
+					     bool status)
+{
+	int ret;
+
+	/* Enable/Disable INT_MAP0 mapping */
+	ret = i2c_smbus_read_byte_data(data->client,  BMG160_REG_INT_MAP_0);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error reading reg_int_map0\n");
+		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 writing reg_int_map0\n");
+		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 writing 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 writing reg_motion_intr\n");
+			return ret;
+		}
+
+		/*
+		 * New data interrupt is always non-latched,
+		 * which will have higher priority, so no need
+		 * to set latched mode, we will be flooded anyway with INTR
+		 */
+		if (!data->dready_trigger_on) {
+			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;
+			}
+		}
+
+		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 0;
+}
+
+static int bmg160_setup_new_data_interrupt(struct bmg160_data *data,
+					   bool status)
+{
+	int ret;
+
+	/* Enable/Disable INT_MAP1 mapping */
+	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_INT_MAP_1);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error reading reg_int_map1\n");
+		return ret;
+	}
+
+	if (status)
+		ret |= BMG160_INT_MAP_1_BIT_NEW_DATA;
+	else
+		ret &= ~BMG160_INT_MAP_1_BIT_NEW_DATA;
+
+	ret = i2c_smbus_write_byte_data(data->client,
+					BMG160_REG_INT_MAP_1,
+					ret);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error writing reg_int_map1\n");
+		return ret;
+	}
+
+	if (status) {
+		ret = i2c_smbus_write_byte_data(data->client,
+						BMG160_REG_INT_RST_LATCH,
+						BMG160_INT_MODE_NON_LATCH_INT |
+						BMG160_INT_MODE_LATCH_RESET);
+		if (ret < 0) {
+			dev_err(&data->client->dev,
+				"Error writing reg_rst_latch\n");
+				return ret;
+		}
+
+		ret = i2c_smbus_write_byte_data(data->client,
+						BMG160_REG_INT_EN_0,
+						BMG160_DATA_ENABLE_INT);
+
+	} else {
+		/* Restore interrupt mode */
+		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;
+		}
+
+		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 0;
+}
+
+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 reg_range\n");
+				return ret;
+			}
+			data->dps_range = bmg160_scale_table[i].dps_range;
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static int bmg160_get_temp(struct bmg160_data *data, int *val)
+{
+	int ret;
+
+	mutex_lock(&data->mutex);
+	ret = bmg160_set_power_state(data, true);
+	if (ret < 0) {
+		mutex_unlock(&data->mutex);
+		return ret;
+	}
+
+	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_TEMP);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error reading reg_temp\n");
+		bmg160_set_power_state(data, false);
+		mutex_unlock(&data->mutex);
+		return ret;
+	}
+
+	*val = sign_extend32(ret, 7);
+	ret = bmg160_set_power_state(data, false);
+	mutex_unlock(&data->mutex);
+	if (ret < 0)
+		return ret;
+
+	return IIO_VAL_INT;
+}
+
+static int bmg160_get_axis(struct bmg160_data *data, int axis, int *val)
+{
+	int ret;
+
+	mutex_lock(&data->mutex);
+	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(axis));
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error reading axis %d\n", axis);
+		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;
+}
+
+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:
+		switch (chan->type) {
+		case IIO_TEMP:
+			return bmg160_get_temp(data, val);
+		case IIO_ANGL_VEL:
+			if (iio_buffer_enabled(indio_dev))
+				return -EBUSY;
+			else
+				return bmg160_get_axis(data, chan->scan_index,
+						       val);
+		default:
+			return -EINVAL;
+		}
+	case IIO_CHAN_INFO_OFFSET:
+		if (chan->type == IIO_TEMP) {
+			*val = BMG160_TEMP_CENTER_VAL;
+			return IIO_VAL_INT;
+		} else
+			return -EINVAL;
+	case IIO_CHAN_INFO_SCALE:
+		*val = 0;
+		switch (chan->type) {
+		case IIO_TEMP:
+			*val2 = 500000;
+			return IIO_VAL_INT_PLUS_MICRO;
+		case IIO_ANGL_VEL:
+		{
+			int i;
+
+			for (i = 0; i < ARRAY_SIZE(bmg160_scale_table); ++i) {
+				if (bmg160_scale_table[i].dps_range ==
+							data->dps_range) {
+					*val2 = bmg160_scale_table[i].scale;
+					return IIO_VAL_INT_PLUS_MICRO;
+				}
+			}
+			return -EINVAL;
+		}
+		default:
+			return -EINVAL;
+		}
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		*val2 = 0;
+		mutex_lock(&data->mutex);
+		ret = bmg160_get_bw(data, val);
+		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);
+		/*
+		 * Section 4.2 of spec
+		 * In suspend mode, the only supported operations are reading
+		 * registers as well as writing to the (0x14) softreset
+		 * register. Since we will be in suspend mode by default, change
+		 * mode to power on for other writes.
+		 */
+		ret = bmg160_set_power_state(data, true);
+		if (ret < 0) {
+			mutex_unlock(&data->mutex);
+			return ret;
+		}
+		ret = bmg160_set_bw(data, val);
+		if (ret < 0) {
+			bmg160_set_power_state(data, false);
+			mutex_unlock(&data->mutex);
+			return ret;
+		}
+		ret = bmg160_set_power_state(data, false);
Could this end up disabling the part when in triggered mode?
+		mutex_unlock(&data->mutex);
+		return ret;
+	case IIO_CHAN_INFO_SCALE:
+		if (val)
+			return -EINVAL;
+
+		mutex_lock(&data->mutex);
+		/* Refer to comments above for the suspend mode ops */
+		ret = bmg160_set_power_state(data, true);
+		if (ret < 0) {
+			mutex_unlock(&data->mutex);
+			return ret;
+		}
+		ret = bmg160_set_scale(data, val2);
+		if (ret < 0) {
+			bmg160_set_power_state(data, false);
+			mutex_unlock(&data->mutex);
+			return ret;
+		}
+		ret = bmg160_set_power_state(data, false);
+		mutex_unlock(&data->mutex);
+		return ret;
+	default:
+		return -EINVAL;
+	}
+
+	return -EINVAL;
+}
+
+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:
+		if (data->ev_enable_state)
+			return -EBUSY;
+		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 (state && data->ev_enable_state)
+		return 0;
+
+	mutex_lock(&data->mutex);
+
+	if (!state && data->motion_trigger_on) {
+		data->ev_enable_state = 0;
+		mutex_unlock(&data->mutex);
+		return 0;
+	}
+	/*
+	 * We will expect the enable and disable to do operation in
+	 * in reverse order. This will happen here anyway as our
+	 * resume operation uses sync mode runtime pm calls, the
+	 * suspend operation will be delayed by autosuspend delay
+	 * So the disable operation will still happen in reverse of
+	 * enable operation. When runtime pm is disabled the mode
+	 * is always on so sequence doesn't matter
+	 */
Thanks for the detailed comment!
+	ret = bmg160_set_power_state(data, state);
+	if (ret < 0) {
+		mutex_unlock(&data->mutex);
+		return ret;
+	}
+
+	ret =  bmg160_setup_any_motion_interrupt(data, state);
+	if (ret < 0) {
+		mutex_unlock(&data->mutex);
+		return ret;
+	}
+
+	data->ev_enable_state = state;
+	mutex_unlock(&data->mutex);
+
+	return 0;
+}
+
+static int bmg160_validate_trigger(struct iio_dev *indio_dev,
+				   struct iio_trigger *trig)
+{
+	struct bmg160_data *data = iio_priv(indio_dev);
+
+	if (data->dready_trig != trig && data->motion_trig != trig)
+		return -EINVAL;
+
+	return 0;
+}
+
+static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("100 200 400 1000 2000");
+
+static IIO_CONST_ATTR(in_anglvel_scale_available,
+		      "0.001065 0.000532 0.000266 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_RISING | IIO_EV_DIR_FALLING,
+		.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,					\
+	},								\
+	.event_spec = &bmg160_event,					\
+	.num_event_specs = 1						\
+}
+
+static const struct iio_chan_spec bmg160_channels[] = {
+	{
+		.type = IIO_TEMP,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+				      BIT(IIO_CHAN_INFO_SCALE) |
+				      BIT(IIO_CHAN_INFO_OFFSET),
+		.scan_index = -1,
+	},
+	BMG160_CHANNEL(X),
+	BMG160_CHANNEL(Y),
+	BMG160_CHANNEL(Z),
+	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	= bmg160_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,
+					   data->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;
+
+	/* new data interrupts don't need ack */
+	if (data->dready_trigger_on)
+		return 0;
+
+	/* 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;
+
+	mutex_lock(&data->mutex);
+
+	if (!state && data->ev_enable_state && data->motion_trigger_on) {
+		data->motion_trigger_on = false;
+		mutex_unlock(&data->mutex);
+		return 0;
+	}
+
+	/*
+	 * Refer to comment in bmg160_write_event_config for
+	 * enable/disable operation order
+	 */
+	ret = bmg160_set_power_state(data, state);
+	if (ret < 0) {
+		mutex_unlock(&data->mutex);
+		return ret;
+	}
+	if (data->motion_trig == trig)
+		ret =  bmg160_setup_any_motion_interrupt(data, state);
+	else
+		ret = bmg160_setup_new_data_interrupt(data, state);
+	if (ret < 0) {
+		mutex_unlock(&data->mutex);
+		return ret;
+	}
+	if (data->motion_trig == trig)
+		data->motion_trigger_on = state;
+	else
+		data->dready_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;
+	int dir;
+
+	ret = i2c_smbus_read_byte_data(data->client, BMG160_REG_INT_STATUS_2);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error reading reg_int_status2\n");
+		goto ack_intr_status;
+	}
+
+	if (ret & 0x08)
+		dir = IIO_EV_DIR_RISING;
+	else
+		dir = IIO_EV_DIR_FALLING;
+
+	if (ret & BMG160_ANY_MOTION_MASK)
+		iio_push_event(indio_dev, IIO_MOD_EVENT_CODE(IIO_ANGL_VEL,
+							0,
+							IIO_MOD_X_OR_Y_OR_Z,
+							IIO_EV_TYPE_ROC,
+							dir),
+							data->timestamp);
+
+ack_intr_status:
+	if (!data->dready_trigger_on) {
+		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);
+
+	data->timestamp = iio_get_time_ns();
+
+	if (data->dready_trigger_on)
+		iio_trigger_poll(data->dready_trig);
+	else if (data->motion_trigger_on)
+		iio_trigger_poll(data->motion_trig);
+
+	if (data->ev_enable_state)
+		return IRQ_WAKE_THREAD;
+	else
+		return IRQ_HANDLED;
+
+}
+
+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;
+	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) {
+		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;
+
+		data->dready_trig = devm_iio_trigger_alloc(&client->dev,
+							   "%s-dev%d",
+							   indio_dev->name,
+							   indio_dev->id);
+		if (!data->dready_trig)
+			return -ENOMEM;
+
+		data->motion_trig = devm_iio_trigger_alloc(&client->dev,
+							  "%s-any-motion-dev%d",
+							  indio_dev->name,
+							  indio_dev->id);
+		if (!data->motion_trig)
+			return -ENOMEM;
+
+		data->dready_trig->dev.parent = &client->dev;
+		data->dready_trig->ops = &bmg160_trigger_ops;
+		iio_trigger_set_drvdata(data->dready_trig, indio_dev);
+		ret = iio_trigger_register(data->dready_trig);
+		if (ret)
+			return ret;
+
+		data->motion_trig->dev.parent = &client->dev;
+		data->motion_trig->ops = &bmg160_trigger_ops;
+		iio_trigger_set_drvdata(data->motion_trig, indio_dev);
+		ret = iio_trigger_register(data->motion_trig);
+		if (ret) {
+			data->motion_trig = NULL;
+			goto err_trigger_unregister;
+		}
+
+		ret = iio_triggered_buffer_setup(indio_dev,
+						 NULL,
+						 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);
+	pm_runtime_set_autosuspend_delay(&client->dev,
+					 BMG160_AUTO_SUSPEND_DELAY_MS);
+	pm_runtime_use_autosuspend(&client->dev);
+
+	return 0;
+
+err_iio_unregister:
+	iio_device_unregister(indio_dev);
+err_buffer_cleanup:
+	if (data->dready_trig)
+		iio_triggered_buffer_cleanup(indio_dev);
+err_trigger_unregister:
+	if (data->dready_trig)
+		iio_trigger_unregister(data->dready_trig);
+	if (data->motion_trig)
+		iio_trigger_unregister(data->motion_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);
+
+	iio_device_unregister(indio_dev);
+
+	if (data->dready_trig) {
+		iio_triggered_buffer_cleanup(indio_dev);
+		iio_trigger_unregister(data->dready_trig);
+		iio_trigger_unregister(data->motion_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->dready_trigger_on || data->motion_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)
+{
+	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");


--
To unsubscribe from this list: send the line "unsubscribe linux-iio" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Input]     [Linux Kernel]     [Linux SCSI]     [X.org]

  Powered by Linux