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* [PATCH v2] iio: imu: Add support for Kionix KMX61 sensor
@ 2014-11-10 17:24 Daniel Baluta
  2014-11-16 21:10 ` Jonathan Cameron
  2014-11-17 13:46 ` Peter Meerwald
  0 siblings, 2 replies; 6+ messages in thread
From: Daniel Baluta @ 2014-11-10 17:24 UTC (permalink / raw)
  To: jic23; +Cc: linux-iio, srinivas.pandruvada, linux-kernel, daniel.baluta

Minimal implementation for KMX61 6-axis accelerometer/magnetometer. It exports
raw accel/magn readings together with scale and sampling frequency.

Datasheet will be available at:
http://www.kionix.com/6-axis-accelerometer-magnetometer/kmx61

Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
---
Changes since v1:
	* serialize non-atomic operations with a mutex (set_odr/get_odr, set_scale).
	* no need to protect reading info scale because it reduces to reading an u8
	which should be atomic on all arches
	* *note* - read_measurment is an atomic operation
	
 drivers/iio/imu/Kconfig  |   9 +
 drivers/iio/imu/Makefile |   2 +
 drivers/iio/imu/kmx61.c  | 590 +++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 601 insertions(+)
 create mode 100644 drivers/iio/imu/kmx61.c

diff --git a/drivers/iio/imu/Kconfig b/drivers/iio/imu/Kconfig
index 2b0e451..d675f43 100644
--- a/drivers/iio/imu/Kconfig
+++ b/drivers/iio/imu/Kconfig
@@ -25,6 +25,15 @@ config ADIS16480
 	  Say yes here to build support for Analog Devices ADIS16375, ADIS16480,
 	  ADIS16485, ADIS16488 inertial sensors.
 
+config KMX61
+	tristate "Kionix KMX61 6-axis accelerometer and magnetometer"
+	depends on I2C
+	help
+	  Say Y here if you want to build a driver for Kionix KMX61 6-axis accelerometer
+	  and magnetometer.
+	  To compile this driver as module, choose M here: the module will be called
+	  kmx61.
+
 source "drivers/iio/imu/inv_mpu6050/Kconfig"
 
 endmenu
diff --git a/drivers/iio/imu/Makefile b/drivers/iio/imu/Makefile
index 114d2c1..e1e6e3d 100644
--- a/drivers/iio/imu/Makefile
+++ b/drivers/iio/imu/Makefile
@@ -14,3 +14,5 @@ adis_lib-$(CONFIG_IIO_ADIS_LIB_BUFFER) += adis_buffer.o
 obj-$(CONFIG_IIO_ADIS_LIB) += adis_lib.o
 
 obj-y += inv_mpu6050/
+
+obj-$(CONFIG_KMX61) += kmx61.o
diff --git a/drivers/iio/imu/kmx61.c b/drivers/iio/imu/kmx61.c
new file mode 100644
index 0000000..6135a16
--- /dev/null
+++ b/drivers/iio/imu/kmx61.c
@@ -0,0 +1,590 @@
+/*
+ * KMX61 - Kionix 6-axis Accelerometer/Magnetometer
+ *
+ * Copyright (c) 2014, Intel Corporation.
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License.  See the file COPYING in the main
+ * directory of this archive for more details.
+ *
+ * IIO driver for KMX61 (7-bit I2C slave address 0x0E or 0x0F).
+ *
+ * TODO: buffer, interrupt, thresholds, acpi, temperature sensor
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define KMX61_DRV_NAME "kmx61"
+
+#define KMX61_REG_WHO_AM_I		0x00
+
+#define KMX61_ACC_XOUT_L		0x0A
+
+#define KMX61_ACC_XOUT_H		0x0B
+#define KMX61_ACC_YOUT_L		0x0C
+#define KMX61_ACC_YOUT_H		0x0D
+#define KMX61_ACC_ZOUT_L		0x0E
+#define KMX61_ACC_ZOUT_H		0x0F
+
+#define KMX61_MAG_XOUT_L		0x12
+
+#define KMX61_MAG_XOUT_H		0x13
+#define KMX61_MAG_YOUT_L		0x14
+#define KMX61_MAG_YOUT_H		0x15
+#define KMX61_MAG_ZOUT_L		0x16
+#define KMX61_MAG_ZOUT_H		0x17
+
+#define KMX61_REG_ODCNTL		0x2C
+
+#define KMX61_REG_STBY			0x29
+#define KMX61_REG_CTRL1			0x2A
+
+#define KMX61_REG_COTR			0x3C
+
+#define KMX61_ACC_STBY_BIT	BIT(0)
+#define KMX61_MAG_STBY_BIT	BIT(1)
+#define KMX61_ACT_STBY_BIT	BIT(7)
+
+#define KMX61_ALL_STBY		(KMX61_ACC_STBY_BIT | KMX61_MAG_STBY_BIT)
+
+#define KMX61_REG_CTRL1_GSEL0_SHIFT	0
+#define KMX61_REG_CTRL1_GSEL1_SHIFT	1
+#define KMX61_REG_CTRL1_GSEL0_MASK	0x01
+#define KMX61_REG_CTRL1_GSEL1_MASK	0x02
+
+#define KMX61_REG_CTRL1_BIT_RES		BIT(4)
+
+#define KMX61_ACC_ODR_SHIFT	0
+#define KMX61_MAG_ODR_SHIFT	4
+#define KMX61_ACC_ODR_MASK	0x0F
+#define KMX61_MAG_ODR_MASK	0xF0
+
+#define KMX61_CHIP_ID		0x12
+
+struct kmx61_data {
+	struct i2c_client *client;
+	/* serialize access to non-atomic ops, e.g set_mode */
+	struct mutex lock;
+	u8 range;
+	u8 odr_bits;
+};
+
+enum kmx61_range {
+	KMX61_RANGE_2G,
+	KMX61_RANGE_4G,
+	KMX61_RANGE_8G,
+};
+
+enum kmx61_scan {
+	KMX61_SCAN_ACC_X,
+	KMX61_SCAN_ACC_Y,
+	KMX61_SCAN_ACC_Z,
+	KMX61_SCAN_TEMP,
+	KMX61_SCAN_MAG_X,
+	KMX61_SCAN_MAG_Y,
+	KMX61_SCAN_MAG_Z,
+};
+
+static const struct {
+	u16 scale;
+	u8 gsel0;
+	u8 gsel1;
+} kmx61_scale_table[] = {
+	{9582, 0, 0},
+	{19163, 1, 0},
+	{38326, 0, 1},
+};
+
+/* KMX61 devices */
+#define KMX61_ACC	0x01
+#define KMX61_MAG	0x02
+
+static const struct {
+	int val;
+	int val2;
+	int odr_bits;
+} samp_freq_table[] = { {12, 500000, 0x00},
+			{25, 0, 0x01},
+			{50, 0, 0x02},
+			{100, 0, 0x03},
+			{200, 0, 0x04},
+			{400, 0, 0x05},
+			{800, 0, 0x06},
+			{1600, 0, 0x07},
+			{0, 781000, 0x08},
+			{1, 563000, 0x09},
+			{3, 125000, 0x0A},
+			{6, 250000, 0x0B} };
+
+static IIO_CONST_ATTR(accel_scale_available, "0.009582 0.019163 0.038326");
+static IIO_CONST_ATTR(magn_scale_available, "0.001465");
+static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
+	"0.781000 1.563000 3.125000 6.250000 12.500000 25 50 100 200 400 800");
+
+static struct attribute *kmx61_attributes[] = {
+	&iio_const_attr_accel_scale_available.dev_attr.attr,
+	&iio_const_attr_magn_scale_available.dev_attr.attr,
+	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group kmx61_attribute_group = {
+	.attrs = kmx61_attributes,
+};
+
+#define KMX61_ACC_CHAN(_axis, _index) { \
+	.type = IIO_ACCEL, \
+	.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 = _index, \
+	.scan_type = { \
+		.sign = 's', \
+		.realbits = 12, \
+		.storagebits = 16, \
+		.shift = 4, \
+		.endianness = IIO_BE, \
+	}, \
+}
+
+#define KMX61_MAG_CHAN(_axis, _index) { \
+	.type = IIO_MAGN, \
+	.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 = _index, \
+	.scan_type = { \
+		.sign = 's', \
+		.realbits = 14, \
+		.storagebits = 16, \
+		.shift = 2, \
+		.endianness = IIO_BE, \
+	}, \
+}
+
+static const struct iio_chan_spec kmx61_channels[] = {
+	KMX61_ACC_CHAN(X, KMX61_SCAN_ACC_X),
+	KMX61_ACC_CHAN(Y, KMX61_SCAN_ACC_Y),
+	KMX61_ACC_CHAN(Z, KMX61_SCAN_ACC_Z),
+	KMX61_MAG_CHAN(X, KMX61_SCAN_MAG_X),
+	KMX61_MAG_CHAN(Y, KMX61_SCAN_MAG_Y),
+	KMX61_MAG_CHAN(Z, KMX61_SCAN_MAG_Z),
+};
+
+static int kmx61_convert_freq_to_bit(int val, int val2)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(samp_freq_table); i++)
+		if (val == samp_freq_table[i].val &&
+		    val2 == samp_freq_table[i].val2)
+			return samp_freq_table[i].odr_bits;
+	return -EINVAL;
+}
+
+static int kmx61_set_mode(struct kmx61_data *data, u8 mode, u8 device)
+{
+	int ret;
+
+	ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_STBY);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error reading reg_stby\n");
+		return ret;
+	}
+	if (device & KMX61_ACC) {
+		if (mode & KMX61_ACC_STBY_BIT)
+			ret |= KMX61_ACC_STBY_BIT;
+		else
+			ret &= ~KMX61_ACC_STBY_BIT;
+	}
+
+	if (device & KMX61_MAG) {
+		if (mode & KMX61_MAG_STBY_BIT)
+			ret |= KMX61_MAG_STBY_BIT;
+		else
+			ret &= ~KMX61_MAG_STBY_BIT;
+	}
+
+	ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_STBY, ret);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error writing reg_stby\n");
+		return ret;
+	}
+
+	return ret;
+}
+
+static int kmx61_get_mode(struct kmx61_data *data, u8 *mode, u8 device)
+{
+	int ret;
+
+	ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_STBY);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error reading reg_stby\n");
+		return ret;
+	}
+	*mode = 0;
+
+	if (device & KMX61_ACC) {
+		if (ret & KMX61_ACC_STBY_BIT)
+			*mode |= KMX61_ACC_STBY_BIT;
+		else
+			*mode &= ~KMX61_ACC_STBY_BIT;
+	}
+
+	if (device & KMX61_MAG) {
+		if (ret & KMX61_MAG_STBY_BIT)
+			*mode |= KMX61_MAG_STBY_BIT;
+		else
+			*mode &= ~KMX61_MAG_STBY_BIT;
+	}
+
+	return 0;
+}
+
+static int kmx61_set_odr(struct kmx61_data *data, int val, int val2, u8 device)
+{
+	int ret;
+	u8 mode;
+	int lodr_bits, odr_bits;
+
+	ret = kmx61_get_mode(data, &mode, KMX61_ACC | KMX61_MAG);
+	if (ret < 0)
+		return ret;
+
+	lodr_bits = kmx61_convert_freq_to_bit(val, val2);
+	if (lodr_bits < 0)
+		return lodr_bits;
+
+	/* To change ODR, accel and magn must be in STDBY */
+	ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG);
+	if (ret < 0)
+		return ret;
+
+	odr_bits = 0;
+	if (device & KMX61_ACC)
+		odr_bits |= lodr_bits;
+	if (device & KMX61_MAG)
+		odr_bits |= (lodr_bits << KMX61_MAG_ODR_SHIFT);
+
+	ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_ODCNTL,
+					odr_bits);
+	if (ret < 0)
+		return ret;
+
+	ret = kmx61_set_mode(data, mode, KMX61_ACC | KMX61_MAG);
+	if (ret < 0)
+		return ret;
+
+	data->odr_bits = lodr_bits;
+
+	return 0;
+}
+
+static
+int kmx61_get_odr(struct kmx61_data *data, int *val, int *val2, u8 device)
+{	int i;
+	u8 lodr_bits;
+
+	if (device & KMX61_ACC)
+		lodr_bits = (data->odr_bits >> KMX61_ACC_ODR_SHIFT) &
+			     KMX61_ACC_ODR_MASK;
+	else if (device & KMX61_MAG)
+		lodr_bits = (data->odr_bits >> KMX61_MAG_ODR_SHIFT) &
+			     KMX61_MAG_ODR_MASK;
+	else
+		return -EINVAL;
+
+	for (i = 0; i < ARRAY_SIZE(samp_freq_table); i++)
+		if (lodr_bits == samp_freq_table[i].odr_bits) {
+			*val = samp_freq_table[i].val;
+			*val2 = samp_freq_table[i].val2;
+			return 0;
+		}
+	return -EINVAL;
+}
+
+static int kmx61_set_range(struct kmx61_data *data, int range)
+{
+	int ret;
+
+	ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_CTRL1);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error reading reg_ctrl1\n");
+		return ret;
+	}
+
+	ret &= ~(KMX61_REG_CTRL1_GSEL0_MASK | KMX61_REG_CTRL1_GSEL1_MASK);
+	ret |= kmx61_scale_table[range].gsel0 << KMX61_REG_CTRL1_GSEL0_SHIFT;
+	ret |= kmx61_scale_table[range].gsel1 << KMX61_REG_CTRL1_GSEL1_SHIFT;
+
+	ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_CTRL1, ret);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error writing reg_ctrl1\n");
+		return ret;
+	}
+
+	data->range = range;
+
+	return 0;
+}
+
+static int kmx61_set_scale(struct kmx61_data *data, int val)
+{
+	int ret, i;
+	u8  mode;
+
+	for (i = 0; i < ARRAY_SIZE(kmx61_scale_table); i++) {
+		if (kmx61_scale_table[i].scale == val) {
+			ret = kmx61_get_mode(data, &mode,
+					     KMX61_ACC | KMX61_MAG);
+			if (ret < 0)
+				return ret;
+
+			ret = kmx61_set_mode(data, KMX61_ALL_STBY,
+					     KMX61_ACC | KMX61_MAG);
+			if (ret < 0)
+				return ret;
+
+			ret = kmx61_set_range(data, i);
+			if (ret < 0)
+				return ret;
+
+			ret = kmx61_set_mode(data, mode,
+					     KMX61_ACC | KMX61_MAG);
+			if (ret < 0)
+				return ret;
+
+			return 0;
+		}
+	}
+	return -EINVAL;
+}
+
+static int kmx61_chip_init(struct kmx61_data *data)
+{
+	int ret;
+
+	ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_WHO_AM_I);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "Error reading who_am_i\n");
+		return ret;
+	}
+
+	if (ret != KMX61_CHIP_ID) {
+		dev_err(&data->client->dev,
+			"Wrong chip id, got %x expected %x\n",
+			 ret, KMX61_CHIP_ID);
+		return -EINVAL;
+	}
+
+	/* set accel 12bit, 4g range */
+	ret = kmx61_set_range(data, KMX61_RANGE_4G);
+	if (ret < 0)
+		return ret;
+
+	/* put accel and magnetometer in operating mode */
+	ret = kmx61_set_mode(data, 0, KMX61_ACC | KMX61_MAG);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static int kmx61_read_measurement(struct kmx61_data *data, int base, int offset)
+{
+	int ret;
+	u8 reg = base + offset * 2;
+
+	ret = i2c_smbus_read_word_data(data->client, reg);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "failed to read reg at %x\n", reg);
+		return ret;
+	}
+
+	return ret;
+}
+
+static int kmx61_read_raw(struct iio_dev *indio_dev,
+			      struct iio_chan_spec const *chan, int *val,
+			      int *val2, long mask)
+{
+	struct kmx61_data *data = iio_priv(indio_dev);
+	int ret;
+	u8 base_reg;
+	u8 device;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		switch (chan->type) {
+		case IIO_ACCEL: case IIO_MAGN:
+			base_reg = KMX61_ACC_XOUT_L;
+			break;
+		default:
+			return -EINVAL;
+		}
+		ret = kmx61_read_measurement(data, base_reg, chan->scan_index);
+		if (ret < 0)
+			return ret;
+		*val = sign_extend32(ret >> chan->scan_type.shift,
+				     chan->scan_type.realbits - 1);
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SCALE:
+		switch (chan->type) {
+		case IIO_ACCEL:
+			*val = 0;
+			*val2 = kmx61_scale_table[data->range].scale;
+			return IIO_VAL_INT_PLUS_MICRO;
+		case IIO_MAGN:
+			/* 14 bits res, 1465 microGauss per magn count */
+			*val = 0;
+			*val2 = 1465;
+			return IIO_VAL_INT_PLUS_MICRO;
+		default:
+			break;
+		}
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		switch (chan->type) {
+		case IIO_ACCEL:
+			device = KMX61_ACC;
+			break;
+		case IIO_MAGN:
+			device = KMX61_MAG;
+			break;
+		default:
+			return -EINVAL;
+		}
+
+		mutex_lock(&data->lock);
+		ret = kmx61_get_odr(data, val, val2, device);
+		mutex_unlock(&data->lock);
+		if (ret)
+			return -EINVAL;
+		return IIO_VAL_INT_PLUS_MICRO;
+	}
+	return -EINVAL;
+}
+
+static int kmx61_write_raw(struct iio_dev *indio_dev,
+			       struct iio_chan_spec const *chan, int val,
+			       int val2, long mask)
+{
+	struct kmx61_data *data = iio_priv(indio_dev);
+	int ret;
+	u8 device;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		switch (chan->type) {
+		case IIO_ACCEL:
+			device = KMX61_ACC;
+			break;
+		case IIO_MAGN:
+			device = KMX61_MAG;
+			break;
+		default:
+			return -EINVAL;
+		}
+		mutex_lock(&data->lock);
+		ret = kmx61_set_odr(data, val, val2, device);
+		mutex_unlock(&data->lock);
+		break;
+	case IIO_CHAN_INFO_SCALE:
+		switch (chan->type) {
+		case IIO_ACCEL:
+			mutex_lock(&data->lock);
+			ret = kmx61_set_scale(data, val2);
+			mutex_unlock(&data->lock);
+			break;
+		default:
+			ret  = -EINVAL;
+		}
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static const struct iio_info kmx61_info = {
+	.driver_module		= THIS_MODULE,
+	.read_raw		= kmx61_read_raw,
+	.write_raw		= kmx61_write_raw,
+	.attrs			= &kmx61_attribute_group,
+};
+
+static int kmx61_probe(struct i2c_client *client,
+		       const struct i2c_device_id *id)
+{
+	struct kmx61_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;
+
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->info = &kmx61_info;
+	indio_dev->channels = kmx61_channels;
+	indio_dev->num_channels = ARRAY_SIZE(kmx61_channels);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+
+	mutex_init(&data->lock);
+
+	ret = kmx61_chip_init(data);
+	if (ret < 0)
+		return ret;
+
+	return iio_device_register(indio_dev);
+}
+
+static int kmx61_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct kmx61_data *data = iio_priv(indio_dev);
+	int ret;
+
+	iio_device_unregister(indio_dev);
+
+	mutex_lock(&data->lock);
+	ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG);
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static const struct i2c_device_id kmx61_id[] = {
+	{"kmx61", 0},
+	{}
+};
+
+MODULE_DEVICE_TABLE(i2c, kmx61_id);
+
+static struct i2c_driver kmx61_driver = {
+	.driver = {
+		.name = "kmx61",
+	},
+	.probe		= kmx61_probe,
+	.remove		= kmx61_remove,
+	.id_table	= kmx61_id,
+};
+
+module_i2c_driver(kmx61_driver);
+
+MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
+MODULE_DESCRIPTION("KMX61 accelerometer/magnetometer driver");
+MODULE_LICENSE("GPL v2");
-- 
1.9.1


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [PATCH v2] iio: imu: Add support for Kionix KMX61 sensor
  2014-11-10 17:24 [PATCH v2] iio: imu: Add support for Kionix KMX61 sensor Daniel Baluta
@ 2014-11-16 21:10 ` Jonathan Cameron
  2014-11-17 12:12   ` Daniel Baluta
  2014-11-17 13:46 ` Peter Meerwald
  1 sibling, 1 reply; 6+ messages in thread
From: Jonathan Cameron @ 2014-11-16 21:10 UTC (permalink / raw)
  To: Daniel Baluta; +Cc: linux-iio, srinivas.pandruvada, linux-kernel

On 10/11/14 17:24, Daniel Baluta wrote:
> Minimal implementation for KMX61 6-axis accelerometer/magnetometer. It exports
> raw accel/magn readings together with scale and sampling frequency.
> 
> Datasheet will be available at:
> http://www.kionix.com/6-axis-accelerometer-magnetometer/kmx61
> 
> Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Looking very nice.    I made a few more comments inline but only
one was more than a comment - I added a check on val==0 in the obvious
place.  Please take a look at the testing branch of iio.git to make
sure I didn't mess anything up!

Applied to the togreg branch of iio.git - initially pushed out as testing
for the autobuilders to play with it.

Jonathan
> ---
> Changes since v1:
> 	* serialize non-atomic operations with a mutex (set_odr/get_odr, set_scale).
> 	* no need to protect reading info scale because it reduces to reading an u8
> 	which should be atomic on all arches
> 	* *note* - read_measurment is an atomic operation
> 	
>  drivers/iio/imu/Kconfig  |   9 +
>  drivers/iio/imu/Makefile |   2 +
>  drivers/iio/imu/kmx61.c  | 590 +++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 601 insertions(+)
>  create mode 100644 drivers/iio/imu/kmx61.c
> 
> diff --git a/drivers/iio/imu/Kconfig b/drivers/iio/imu/Kconfig
> index 2b0e451..d675f43 100644
> --- a/drivers/iio/imu/Kconfig
> +++ b/drivers/iio/imu/Kconfig
> @@ -25,6 +25,15 @@ config ADIS16480
>  	  Say yes here to build support for Analog Devices ADIS16375, ADIS16480,
>  	  ADIS16485, ADIS16488 inertial sensors.
>  
> +config KMX61
> +	tristate "Kionix KMX61 6-axis accelerometer and magnetometer"
> +	depends on I2C
> +	help
> +	  Say Y here if you want to build a driver for Kionix KMX61 6-axis accelerometer
> +	  and magnetometer.
> +	  To compile this driver as module, choose M here: the module will be called
> +	  kmx61.
> +
>  source "drivers/iio/imu/inv_mpu6050/Kconfig"
>  
>  endmenu
> diff --git a/drivers/iio/imu/Makefile b/drivers/iio/imu/Makefile
> index 114d2c1..e1e6e3d 100644
> --- a/drivers/iio/imu/Makefile
> +++ b/drivers/iio/imu/Makefile
> @@ -14,3 +14,5 @@ adis_lib-$(CONFIG_IIO_ADIS_LIB_BUFFER) += adis_buffer.o
>  obj-$(CONFIG_IIO_ADIS_LIB) += adis_lib.o
>  
>  obj-y += inv_mpu6050/
> +
> +obj-$(CONFIG_KMX61) += kmx61.o
> diff --git a/drivers/iio/imu/kmx61.c b/drivers/iio/imu/kmx61.c
> new file mode 100644
> index 0000000..6135a16
> --- /dev/null
> +++ b/drivers/iio/imu/kmx61.c
> @@ -0,0 +1,590 @@
> +/*
> + * KMX61 - Kionix 6-axis Accelerometer/Magnetometer
> + *
> + * Copyright (c) 2014, Intel Corporation.
> + *
> + * This file is subject to the terms and conditions of version 2 of
> + * the GNU General Public License.  See the file COPYING in the main
> + * directory of this archive for more details.
> + *
> + * IIO driver for KMX61 (7-bit I2C slave address 0x0E or 0x0F).
> + *
> + * TODO: buffer, interrupt, thresholds, acpi, temperature sensor
> + *
> + */
> +
> +#include <linux/module.h>
> +#include <linux/i2c.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +
> +#define KMX61_DRV_NAME "kmx61"
> +
> +#define KMX61_REG_WHO_AM_I		0x00
> +
> +#define KMX61_ACC_XOUT_L		0x0A
> +
> +#define KMX61_ACC_XOUT_H		0x0B
> +#define KMX61_ACC_YOUT_L		0x0C
> +#define KMX61_ACC_YOUT_H		0x0D
> +#define KMX61_ACC_ZOUT_L		0x0E
> +#define KMX61_ACC_ZOUT_H		0x0F
> +
> +#define KMX61_MAG_XOUT_L		0x12
> +
> +#define KMX61_MAG_XOUT_H		0x13
> +#define KMX61_MAG_YOUT_L		0x14
> +#define KMX61_MAG_YOUT_H		0x15
> +#define KMX61_MAG_ZOUT_L		0x16
> +#define KMX61_MAG_ZOUT_H		0x17
> +
> +#define KMX61_REG_ODCNTL		0x2C
> +
> +#define KMX61_REG_STBY			0x29
> +#define KMX61_REG_CTRL1			0x2A
> +
> +#define KMX61_REG_COTR			0x3C
> +
> +#define KMX61_ACC_STBY_BIT	BIT(0)
> +#define KMX61_MAG_STBY_BIT	BIT(1)
> +#define KMX61_ACT_STBY_BIT	BIT(7)
> +
> +#define KMX61_ALL_STBY		(KMX61_ACC_STBY_BIT | KMX61_MAG_STBY_BIT)
> +
> +#define KMX61_REG_CTRL1_GSEL0_SHIFT	0
> +#define KMX61_REG_CTRL1_GSEL1_SHIFT	1
> +#define KMX61_REG_CTRL1_GSEL0_MASK	0x01
> +#define KMX61_REG_CTRL1_GSEL1_MASK	0x02
> +
> +#define KMX61_REG_CTRL1_BIT_RES		BIT(4)
> +
> +#define KMX61_ACC_ODR_SHIFT	0
> +#define KMX61_MAG_ODR_SHIFT	4
> +#define KMX61_ACC_ODR_MASK	0x0F
> +#define KMX61_MAG_ODR_MASK	0xF0
> +
> +#define KMX61_CHIP_ID		0x12
> +
> +struct kmx61_data {
> +	struct i2c_client *client;
> +	/* serialize access to non-atomic ops, e.g set_mode */
> +	struct mutex lock;
> +	u8 range;
> +	u8 odr_bits;
> +};
> +
> +enum kmx61_range {
> +	KMX61_RANGE_2G,
> +	KMX61_RANGE_4G,
> +	KMX61_RANGE_8G,
> +};
> +
> +enum kmx61_scan {
> +	KMX61_SCAN_ACC_X,
> +	KMX61_SCAN_ACC_Y,
> +	KMX61_SCAN_ACC_Z,
> +	KMX61_SCAN_TEMP,
> +	KMX61_SCAN_MAG_X,
> +	KMX61_SCAN_MAG_Y,
> +	KMX61_SCAN_MAG_Z,
> +};
> +
> +static const struct {
> +	u16 scale;
> +	u8 gsel0;
> +	u8 gsel1;
> +} kmx61_scale_table[] = {
> +	{9582, 0, 0},
> +	{19163, 1, 0},
> +	{38326, 0, 1},
> +};
> +
> +/* KMX61 devices */
> +#define KMX61_ACC	0x01
> +#define KMX61_MAG	0x02
> +
> +static const struct {
> +	int val;
> +	int val2;
> +	int odr_bits;
> +} samp_freq_table[] = { {12, 500000, 0x00},
> +			{25, 0, 0x01},
> +			{50, 0, 0x02},
> +			{100, 0, 0x03},
> +			{200, 0, 0x04},
> +			{400, 0, 0x05},
> +			{800, 0, 0x06},
> +			{1600, 0, 0x07},
> +			{0, 781000, 0x08},
> +			{1, 563000, 0x09},
> +			{3, 125000, 0x0A},
> +			{6, 250000, 0x0B} };
> +
> +static IIO_CONST_ATTR(accel_scale_available, "0.009582 0.019163 0.038326");
> +static IIO_CONST_ATTR(magn_scale_available, "0.001465");
> +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
> +	"0.781000 1.563000 3.125000 6.250000 12.500000 25 50 100 200 400 800");
> +
> +static struct attribute *kmx61_attributes[] = {
> +	&iio_const_attr_accel_scale_available.dev_attr.attr,
> +	&iio_const_attr_magn_scale_available.dev_attr.attr,
> +	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
Interesting.  So sampling frequency is controllable seperately for the
two sensing types, but uses a single set of values.  This is a rare
coherent looking bit of dual sensor type hardware ;)
> +	NULL,
> +};
> +
> +static const struct attribute_group kmx61_attribute_group = {
> +	.attrs = kmx61_attributes,
> +};
> +
> +#define KMX61_ACC_CHAN(_axis, _index) { \
> +	.type = IIO_ACCEL, \
> +	.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 = _index, \
> +	.scan_type = { \
> +		.sign = 's', \
> +		.realbits = 12, \
> +		.storagebits = 16, \
> +		.shift = 4, \
> +		.endianness = IIO_BE, \
> +	}, \
> +}
> +
> +#define KMX61_MAG_CHAN(_axis, _index) { \
> +	.type = IIO_MAGN, \
> +	.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 = _index, \
> +	.scan_type = { \
> +		.sign = 's', \
> +		.realbits = 14, \
> +		.storagebits = 16, \
> +		.shift = 2, \
> +		.endianness = IIO_BE, \
> +	}, \
Wouldn't normally expect scan_index and scan_type in a driver
without buffered support, but you do make use of some of the
elements elsewhere and state that buffered support
is on the todo list so lets leave it here.
> +}
> +
> +static const struct iio_chan_spec kmx61_channels[] = {
> +	KMX61_ACC_CHAN(X, KMX61_SCAN_ACC_X),
> +	KMX61_ACC_CHAN(Y, KMX61_SCAN_ACC_Y),
> +	KMX61_ACC_CHAN(Z, KMX61_SCAN_ACC_Z),
> +	KMX61_MAG_CHAN(X, KMX61_SCAN_MAG_X),
> +	KMX61_MAG_CHAN(Y, KMX61_SCAN_MAG_Y),
> +	KMX61_MAG_CHAN(Z, KMX61_SCAN_MAG_Z),
> +};
> +
> +static int kmx61_convert_freq_to_bit(int val, int val2)
> +{
> +	int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(samp_freq_table); i++)
> +		if (val == samp_freq_table[i].val &&
> +		    val2 == samp_freq_table[i].val2)
> +			return samp_freq_table[i].odr_bits;
> +	return -EINVAL;
> +}
> +
> +static int kmx61_set_mode(struct kmx61_data *data, u8 mode, u8 device)
> +{
> +	int ret;
> +
> +	ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_STBY);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error reading reg_stby\n");
> +		return ret;
> +	}
> +	if (device & KMX61_ACC) {
> +		if (mode & KMX61_ACC_STBY_BIT)
> +			ret |= KMX61_ACC_STBY_BIT;
> +		else
> +			ret &= ~KMX61_ACC_STBY_BIT;
> +	}
> +
> +	if (device & KMX61_MAG) {
> +		if (mode & KMX61_MAG_STBY_BIT)
> +			ret |= KMX61_MAG_STBY_BIT;
> +		else
> +			ret &= ~KMX61_MAG_STBY_BIT;
> +	}
> +
> +	ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_STBY, ret);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error writing reg_stby\n");
> +		return ret;
> +	}
> +
> +	return ret;
> +}
> +
> +static int kmx61_get_mode(struct kmx61_data *data, u8 *mode, u8 device)
> +{
> +	int ret;
> +
> +	ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_STBY);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error reading reg_stby\n");
> +		return ret;
> +	}
> +	*mode = 0;
> +
> +	if (device & KMX61_ACC) {
> +		if (ret & KMX61_ACC_STBY_BIT)
> +			*mode |= KMX61_ACC_STBY_BIT;
> +		else
> +			*mode &= ~KMX61_ACC_STBY_BIT;
> +	}
> +
> +	if (device & KMX61_MAG) {
> +		if (ret & KMX61_MAG_STBY_BIT)
> +			*mode |= KMX61_MAG_STBY_BIT;
> +		else
> +			*mode &= ~KMX61_MAG_STBY_BIT;
> +	}
> +
> +	return 0;
> +}
> +
> +static int kmx61_set_odr(struct kmx61_data *data, int val, int val2, u8 device)
> +{
> +	int ret;
> +	u8 mode;
> +	int lodr_bits, odr_bits;
> +
> +	ret = kmx61_get_mode(data, &mode, KMX61_ACC | KMX61_MAG);
> +	if (ret < 0)
> +		return ret;
> +
> +	lodr_bits = kmx61_convert_freq_to_bit(val, val2);
> +	if (lodr_bits < 0)
> +		return lodr_bits;
> +
> +	/* To change ODR, accel and magn must be in STDBY */
> +	ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG);
> +	if (ret < 0)
> +		return ret;
> +
> +	odr_bits = 0;
> +	if (device & KMX61_ACC)
> +		odr_bits |= lodr_bits;
> +	if (device & KMX61_MAG)
> +		odr_bits |= (lodr_bits << KMX61_MAG_ODR_SHIFT);
> +
> +	ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_ODCNTL,
> +					odr_bits);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = kmx61_set_mode(data, mode, KMX61_ACC | KMX61_MAG);
> +	if (ret < 0)
> +		return ret;
> +
> +	data->odr_bits = lodr_bits;
> +
> +	return 0;
> +}
> +
> +static
> +int kmx61_get_odr(struct kmx61_data *data, int *val, int *val2, u8 device)
> +{	int i;
> +	u8 lodr_bits;
> +
> +	if (device & KMX61_ACC)
> +		lodr_bits = (data->odr_bits >> KMX61_ACC_ODR_SHIFT) &
> +			     KMX61_ACC_ODR_MASK;
> +	else if (device & KMX61_MAG)
> +		lodr_bits = (data->odr_bits >> KMX61_MAG_ODR_SHIFT) &
> +			     KMX61_MAG_ODR_MASK;
> +	else
> +		return -EINVAL;
> +
> +	for (i = 0; i < ARRAY_SIZE(samp_freq_table); i++)
> +		if (lodr_bits == samp_freq_table[i].odr_bits) {
> +			*val = samp_freq_table[i].val;
> +			*val2 = samp_freq_table[i].val2;
> +			return 0;
> +		}
> +	return -EINVAL;
> +}
> +
> +static int kmx61_set_range(struct kmx61_data *data, int range)
> +{
> +	int ret;
> +
> +	ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_CTRL1);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error reading reg_ctrl1\n");
> +		return ret;
> +	}
> +
> +	ret &= ~(KMX61_REG_CTRL1_GSEL0_MASK | KMX61_REG_CTRL1_GSEL1_MASK);
> +	ret |= kmx61_scale_table[range].gsel0 << KMX61_REG_CTRL1_GSEL0_SHIFT;
> +	ret |= kmx61_scale_table[range].gsel1 << KMX61_REG_CTRL1_GSEL1_SHIFT;
> +
> +	ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_CTRL1, ret);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error writing reg_ctrl1\n");
> +		return ret;
> +	}
> +
> +	data->range = range;
> +
> +	return 0;
> +}
> +
I'd be tempted to use a parameter name other than val as that
tends to have a fairly specific meaning in iio drivers
(afterall you pass val2 in here!)  scale would work or
maybe microscale or similar?
> +static int kmx61_set_scale(struct kmx61_data *data, int val)
> +{
> +	int ret, i;
> +	u8  mode;
> +
> +	for (i = 0; i < ARRAY_SIZE(kmx61_scale_table); i++) {
> +		if (kmx61_scale_table[i].scale == val) {
> +			ret = kmx61_get_mode(data, &mode,
> +					     KMX61_ACC | KMX61_MAG);
> +			if (ret < 0)
> +				return ret;
> +
> +			ret = kmx61_set_mode(data, KMX61_ALL_STBY,
> +					     KMX61_ACC | KMX61_MAG);
> +			if (ret < 0)
> +				return ret;
> +
> +			ret = kmx61_set_range(data, i);
> +			if (ret < 0)
> +				return ret;
> +
> +			ret = kmx61_set_mode(data, mode,
> +					     KMX61_ACC | KMX61_MAG);
> +			if (ret < 0)
> +				return ret;
> +
> +			return 0;
> +		}
> +	}
> +	return -EINVAL;
> +}
> +
> +static int kmx61_chip_init(struct kmx61_data *data)
> +{
> +	int ret;
> +
> +	ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_WHO_AM_I);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error reading who_am_i\n");
> +		return ret;
> +	}
> +
> +	if (ret != KMX61_CHIP_ID) {
> +		dev_err(&data->client->dev,
> +			"Wrong chip id, got %x expected %x\n",
> +			 ret, KMX61_CHIP_ID);
> +		return -EINVAL;
> +	}
> +
> +	/* set accel 12bit, 4g range */
> +	ret = kmx61_set_range(data, KMX61_RANGE_4G);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* put accel and magnetometer in operating mode */
> +	ret = kmx61_set_mode(data, 0, KMX61_ACC | KMX61_MAG);
> +	if (ret < 0)
> +		return ret;
> +
> +	return 0;
> +}
> +
> +static int kmx61_read_measurement(struct kmx61_data *data, int base, int offset)
> +{
> +	int ret;
> +	u8 reg = base + offset * 2;
> +
> +	ret = i2c_smbus_read_word_data(data->client, reg);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "failed to read reg at %x\n", reg);
> +		return ret;
> +	}
> +
> +	return ret;
> +}
> +
> +static int kmx61_read_raw(struct iio_dev *indio_dev,
> +			      struct iio_chan_spec const *chan, int *val,
> +			      int *val2, long mask)
> +{
> +	struct kmx61_data *data = iio_priv(indio_dev);
> +	int ret;
> +	u8 base_reg;
> +	u8 device;
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		switch (chan->type) {
> +		case IIO_ACCEL: case IIO_MAGN:
> +			base_reg = KMX61_ACC_XOUT_L;
> +			break;
> +		default:
> +			return -EINVAL;
> +		}
> +		ret = kmx61_read_measurement(data, base_reg, chan->scan_index);
> +		if (ret < 0)
> +			return ret;
> +		*val = sign_extend32(ret >> chan->scan_type.shift,
> +				     chan->scan_type.realbits - 1);
> +		return IIO_VAL_INT;
> +	case IIO_CHAN_INFO_SCALE:
> +		switch (chan->type) {
> +		case IIO_ACCEL:
> +			*val = 0;
> +			*val2 = kmx61_scale_table[data->range].scale;
> +			return IIO_VAL_INT_PLUS_MICRO;
> +		case IIO_MAGN:
> +			/* 14 bits res, 1465 microGauss per magn count */
> +			*val = 0;
> +			*val2 = 1465;
> +			return IIO_VAL_INT_PLUS_MICRO;
> +		default:
> +			break;
> +		}
> +	case IIO_CHAN_INFO_SAMP_FREQ:
> +		switch (chan->type) {
> +		case IIO_ACCEL:
> +			device = KMX61_ACC;
> +			break;
> +		case IIO_MAGN:
> +			device = KMX61_MAG;
> +			break;
> +		default:
> +			return -EINVAL;
> +		}
> +
> +		mutex_lock(&data->lock);
> +		ret = kmx61_get_odr(data, val, val2, device);
> +		mutex_unlock(&data->lock);
> +		if (ret)
> +			return -EINVAL;
> +		return IIO_VAL_INT_PLUS_MICRO;
> +	}
> +	return -EINVAL;
> +}
> +
> +static int kmx61_write_raw(struct iio_dev *indio_dev,
> +			       struct iio_chan_spec const *chan, int val,
> +			       int val2, long mask)
> +{
> +	struct kmx61_data *data = iio_priv(indio_dev);
> +	int ret;
> +	u8 device;
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_SAMP_FREQ:
> +		switch (chan->type) {
> +		case IIO_ACCEL:
> +			device = KMX61_ACC;
> +			break;
> +		case IIO_MAGN:
> +			device = KMX61_MAG;
> +			break;
> +		default:
> +			return -EINVAL;
> +		}
> +		mutex_lock(&data->lock);
> +		ret = kmx61_set_odr(data, val, val2, device);
> +		mutex_unlock(&data->lock);
> +		break;
> +	case IIO_CHAN_INFO_SCALE:
> +		switch (chan->type) {
> +		case IIO_ACCEL:

Should verify that val == 0 incase of crazy userspace input.
> +			mutex_lock(&data->lock);
> +			ret = kmx61_set_scale(data, val2);
> +			mutex_unlock(&data->lock);
> +			break;
> +		default:
> +			ret  = -EINVAL;
> +		}
> +		break;
> +	default:
> +		ret = -EINVAL;
> +	}
> +
> +	return ret;
> +}
> +
> +static const struct iio_info kmx61_info = {
> +	.driver_module		= THIS_MODULE,
> +	.read_raw		= kmx61_read_raw,
> +	.write_raw		= kmx61_write_raw,
> +	.attrs			= &kmx61_attribute_group,
> +};
> +
> +static int kmx61_probe(struct i2c_client *client,
> +		       const struct i2c_device_id *id)
> +{
> +	struct kmx61_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;
> +
> +	indio_dev->dev.parent = &client->dev;
> +	indio_dev->info = &kmx61_info;
> +	indio_dev->channels = kmx61_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(kmx61_channels);
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +
> +	mutex_init(&data->lock);
> +
> +	ret = kmx61_chip_init(data);
> +	if (ret < 0)
> +		return ret;
> +
> +	return iio_device_register(indio_dev);
> +}
> +
> +static int kmx61_remove(struct i2c_client *client)
> +{
> +	struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +	struct kmx61_data *data = iio_priv(indio_dev);
> +	int ret;
> +
> +	iio_device_unregister(indio_dev);
> +
> +	mutex_lock(&data->lock);
> +	ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG);
> +	mutex_unlock(&data->lock);
> +
> +	return ret;
> +}
> +
> +static const struct i2c_device_id kmx61_id[] = {
> +	{"kmx61", 0},
> +	{}
> +};
> +
> +MODULE_DEVICE_TABLE(i2c, kmx61_id);
> +
> +static struct i2c_driver kmx61_driver = {
> +	.driver = {
> +		.name = "kmx61",
> +	},
> +	.probe		= kmx61_probe,
> +	.remove		= kmx61_remove,
> +	.id_table	= kmx61_id,
> +};
> +
> +module_i2c_driver(kmx61_driver);
> +
> +MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
> +MODULE_DESCRIPTION("KMX61 accelerometer/magnetometer driver");
> +MODULE_LICENSE("GPL v2");
> 


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v2] iio: imu: Add support for Kionix KMX61 sensor
  2014-11-16 21:10 ` Jonathan Cameron
@ 2014-11-17 12:12   ` Daniel Baluta
  2014-11-22 10:41     ` Jonathan Cameron
  0 siblings, 1 reply; 6+ messages in thread
From: Daniel Baluta @ 2014-11-17 12:12 UTC (permalink / raw)
  To: Jonathan Cameron
  Cc: Daniel Baluta, linux-iio, Srinivas Pandruvada, Linux Kernel Mailing List

On Sun, Nov 16, 2014 at 11:10 PM, Jonathan Cameron <jic23@kernel.org> wrote:
> On 10/11/14 17:24, Daniel Baluta wrote:
>> Minimal implementation for KMX61 6-axis accelerometer/magnetometer. It exports
>> raw accel/magn readings together with scale and sampling frequency.
>>
>> Datasheet will be available at:
>> http://www.kionix.com/6-axis-accelerometer-magnetometer/kmx61
>>
>> Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
> Looking very nice.    I made a few more comments inline but only
> one was more than a comment - I added a check on val==0 in the obvious
> place.  Please take a look at the testing branch of iio.git to make
> sure I didn't mess anything up!

Thanks! It looks good.

>
> Applied to the togreg branch of iio.git - initially pushed out as testing
> for the autobuilders to play with it.
>
> Jonathan
>> ---
>> Changes since v1:
>>       * serialize non-atomic operations with a mutex (set_odr/get_odr, set_scale).
>>       * no need to protect reading info scale because it reduces to reading an u8
>>       which should be atomic on all arches
>>       * *note* - read_measurment is an atomic operation
>>
>>  drivers/iio/imu/Kconfig  |   9 +
>>  drivers/iio/imu/Makefile |   2 +
>>  drivers/iio/imu/kmx61.c  | 590 +++++++++++++++++++++++++++++++++++++++++++++++
>>  3 files changed, 601 insertions(+)
>>  create mode 100644 drivers/iio/imu/kmx61.c
>>
>> diff --git a/drivers/iio/imu/Kconfig b/drivers/iio/imu/Kconfig
>> index 2b0e451..d675f43 100644
>> --- a/drivers/iio/imu/Kconfig
>> +++ b/drivers/iio/imu/Kconfig
>> @@ -25,6 +25,15 @@ config ADIS16480
>>         Say yes here to build support for Analog Devices ADIS16375, ADIS16480,
>>         ADIS16485, ADIS16488 inertial sensors.
>>
>> +config KMX61
>> +     tristate "Kionix KMX61 6-axis accelerometer and magnetometer"
>> +     depends on I2C
>> +     help
>> +       Say Y here if you want to build a driver for Kionix KMX61 6-axis accelerometer
>> +       and magnetometer.
>> +       To compile this driver as module, choose M here: the module will be called
>> +       kmx61.
>> +
>>  source "drivers/iio/imu/inv_mpu6050/Kconfig"
>>
>>  endmenu
>> diff --git a/drivers/iio/imu/Makefile b/drivers/iio/imu/Makefile
>> index 114d2c1..e1e6e3d 100644
>> --- a/drivers/iio/imu/Makefile
>> +++ b/drivers/iio/imu/Makefile
>> @@ -14,3 +14,5 @@ adis_lib-$(CONFIG_IIO_ADIS_LIB_BUFFER) += adis_buffer.o
>>  obj-$(CONFIG_IIO_ADIS_LIB) += adis_lib.o
>>
>>  obj-y += inv_mpu6050/
>> +
>> +obj-$(CONFIG_KMX61) += kmx61.o
>> diff --git a/drivers/iio/imu/kmx61.c b/drivers/iio/imu/kmx61.c
>> new file mode 100644
>> index 0000000..6135a16
>> --- /dev/null
>> +++ b/drivers/iio/imu/kmx61.c
>> @@ -0,0 +1,590 @@
>> +/*
>> + * KMX61 - Kionix 6-axis Accelerometer/Magnetometer
>> + *
>> + * Copyright (c) 2014, Intel Corporation.
>> + *
>> + * This file is subject to the terms and conditions of version 2 of
>> + * the GNU General Public License.  See the file COPYING in the main
>> + * directory of this archive for more details.
>> + *
>> + * IIO driver for KMX61 (7-bit I2C slave address 0x0E or 0x0F).
>> + *
>> + * TODO: buffer, interrupt, thresholds, acpi, temperature sensor
>> + *
>> + */
>> +
>> +#include <linux/module.h>
>> +#include <linux/i2c.h>
>> +#include <linux/iio/iio.h>
>> +#include <linux/iio/sysfs.h>
>> +
>> +#define KMX61_DRV_NAME "kmx61"
>> +
>> +#define KMX61_REG_WHO_AM_I           0x00
>> +
>> +#define KMX61_ACC_XOUT_L             0x0A
>> +
>> +#define KMX61_ACC_XOUT_H             0x0B
>> +#define KMX61_ACC_YOUT_L             0x0C
>> +#define KMX61_ACC_YOUT_H             0x0D
>> +#define KMX61_ACC_ZOUT_L             0x0E
>> +#define KMX61_ACC_ZOUT_H             0x0F
>> +
>> +#define KMX61_MAG_XOUT_L             0x12
>> +
>> +#define KMX61_MAG_XOUT_H             0x13
>> +#define KMX61_MAG_YOUT_L             0x14
>> +#define KMX61_MAG_YOUT_H             0x15
>> +#define KMX61_MAG_ZOUT_L             0x16
>> +#define KMX61_MAG_ZOUT_H             0x17
>> +
>> +#define KMX61_REG_ODCNTL             0x2C
>> +
>> +#define KMX61_REG_STBY                       0x29
>> +#define KMX61_REG_CTRL1                      0x2A
>> +
>> +#define KMX61_REG_COTR                       0x3C
>> +
>> +#define KMX61_ACC_STBY_BIT   BIT(0)
>> +#define KMX61_MAG_STBY_BIT   BIT(1)
>> +#define KMX61_ACT_STBY_BIT   BIT(7)
>> +
>> +#define KMX61_ALL_STBY               (KMX61_ACC_STBY_BIT | KMX61_MAG_STBY_BIT)
>> +
>> +#define KMX61_REG_CTRL1_GSEL0_SHIFT  0
>> +#define KMX61_REG_CTRL1_GSEL1_SHIFT  1
>> +#define KMX61_REG_CTRL1_GSEL0_MASK   0x01
>> +#define KMX61_REG_CTRL1_GSEL1_MASK   0x02
>> +
>> +#define KMX61_REG_CTRL1_BIT_RES              BIT(4)
>> +
>> +#define KMX61_ACC_ODR_SHIFT  0
>> +#define KMX61_MAG_ODR_SHIFT  4
>> +#define KMX61_ACC_ODR_MASK   0x0F
>> +#define KMX61_MAG_ODR_MASK   0xF0
>> +
>> +#define KMX61_CHIP_ID                0x12
>> +
>> +struct kmx61_data {
>> +     struct i2c_client *client;
>> +     /* serialize access to non-atomic ops, e.g set_mode */
>> +     struct mutex lock;
>> +     u8 range;
>> +     u8 odr_bits;
>> +};
>> +
>> +enum kmx61_range {
>> +     KMX61_RANGE_2G,
>> +     KMX61_RANGE_4G,
>> +     KMX61_RANGE_8G,
>> +};
>> +
>> +enum kmx61_scan {
>> +     KMX61_SCAN_ACC_X,
>> +     KMX61_SCAN_ACC_Y,
>> +     KMX61_SCAN_ACC_Z,
>> +     KMX61_SCAN_TEMP,
>> +     KMX61_SCAN_MAG_X,
>> +     KMX61_SCAN_MAG_Y,
>> +     KMX61_SCAN_MAG_Z,
>> +};
>> +
>> +static const struct {
>> +     u16 scale;
>> +     u8 gsel0;
>> +     u8 gsel1;
>> +} kmx61_scale_table[] = {
>> +     {9582, 0, 0},
>> +     {19163, 1, 0},
>> +     {38326, 0, 1},
>> +};
>> +
>> +/* KMX61 devices */
>> +#define KMX61_ACC    0x01
>> +#define KMX61_MAG    0x02
>> +
>> +static const struct {
>> +     int val;
>> +     int val2;
>> +     int odr_bits;
>> +} samp_freq_table[] = { {12, 500000, 0x00},
>> +                     {25, 0, 0x01},
>> +                     {50, 0, 0x02},
>> +                     {100, 0, 0x03},
>> +                     {200, 0, 0x04},
>> +                     {400, 0, 0x05},
>> +                     {800, 0, 0x06},
>> +                     {1600, 0, 0x07},
>> +                     {0, 781000, 0x08},
>> +                     {1, 563000, 0x09},
>> +                     {3, 125000, 0x0A},
>> +                     {6, 250000, 0x0B} };
>> +
>> +static IIO_CONST_ATTR(accel_scale_available, "0.009582 0.019163 0.038326");
>> +static IIO_CONST_ATTR(magn_scale_available, "0.001465");
>> +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
>> +     "0.781000 1.563000 3.125000 6.250000 12.500000 25 50 100 200 400 800");
>> +
>> +static struct attribute *kmx61_attributes[] = {
>> +     &iio_const_attr_accel_scale_available.dev_attr.attr,
>> +     &iio_const_attr_magn_scale_available.dev_attr.attr,
>> +     &iio_const_attr_sampling_frequency_available.dev_attr.attr,
> Interesting.  So sampling frequency is controllable seperately for the
> two sensing types, but uses a single set of values.  This is a rare
> coherent looking bit of dual sensor type hardware ;)

Yes.

Anyway, when the FIFO hardware buffer is used, it  will be updated
at the faster of the two output data rates

>> +     NULL,
>> +};
>> +
>> +static const struct attribute_group kmx61_attribute_group = {
>> +     .attrs = kmx61_attributes,
>> +};
>> +
>> +#define KMX61_ACC_CHAN(_axis, _index) { \
>> +     .type = IIO_ACCEL, \
>> +     .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 = _index, \
>> +     .scan_type = { \
>> +             .sign = 's', \
>> +             .realbits = 12, \
>> +             .storagebits = 16, \
>> +             .shift = 4, \
>> +             .endianness = IIO_BE, \
>> +     }, \
>> +}
>> +
>> +#define KMX61_MAG_CHAN(_axis, _index) { \
>> +     .type = IIO_MAGN, \
>> +     .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 = _index, \
>> +     .scan_type = { \
>> +             .sign = 's', \
>> +             .realbits = 14, \
>> +             .storagebits = 16, \
>> +             .shift = 2, \
>> +             .endianness = IIO_BE, \
>> +     }, \
> Wouldn't normally expect scan_index and scan_type in a driver
> without buffered support, but you do make use of some of the
> elements elsewhere and state that buffered support
> is on the todo list so lets leave it here.
>> +}
>> +
>> +static const struct iio_chan_spec kmx61_channels[] = {
>> +     KMX61_ACC_CHAN(X, KMX61_SCAN_ACC_X),
>> +     KMX61_ACC_CHAN(Y, KMX61_SCAN_ACC_Y),
>> +     KMX61_ACC_CHAN(Z, KMX61_SCAN_ACC_Z),
>> +     KMX61_MAG_CHAN(X, KMX61_SCAN_MAG_X),
>> +     KMX61_MAG_CHAN(Y, KMX61_SCAN_MAG_Y),
>> +     KMX61_MAG_CHAN(Z, KMX61_SCAN_MAG_Z),
>> +};
>> +
>> +static int kmx61_convert_freq_to_bit(int val, int val2)
>> +{
>> +     int i;
>> +
>> +     for (i = 0; i < ARRAY_SIZE(samp_freq_table); i++)
>> +             if (val == samp_freq_table[i].val &&
>> +                 val2 == samp_freq_table[i].val2)
>> +                     return samp_freq_table[i].odr_bits;
>> +     return -EINVAL;
>> +}
>> +
>> +static int kmx61_set_mode(struct kmx61_data *data, u8 mode, u8 device)
>> +{
>> +     int ret;
>> +
>> +     ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_STBY);
>> +     if (ret < 0) {
>> +             dev_err(&data->client->dev, "Error reading reg_stby\n");
>> +             return ret;
>> +     }
>> +     if (device & KMX61_ACC) {
>> +             if (mode & KMX61_ACC_STBY_BIT)
>> +                     ret |= KMX61_ACC_STBY_BIT;
>> +             else
>> +                     ret &= ~KMX61_ACC_STBY_BIT;
>> +     }
>> +
>> +     if (device & KMX61_MAG) {
>> +             if (mode & KMX61_MAG_STBY_BIT)
>> +                     ret |= KMX61_MAG_STBY_BIT;
>> +             else
>> +                     ret &= ~KMX61_MAG_STBY_BIT;
>> +     }
>> +
>> +     ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_STBY, ret);
>> +     if (ret < 0) {
>> +             dev_err(&data->client->dev, "Error writing reg_stby\n");
>> +             return ret;
>> +     }
>> +
>> +     return ret;
>> +}
>> +
>> +static int kmx61_get_mode(struct kmx61_data *data, u8 *mode, u8 device)
>> +{
>> +     int ret;
>> +
>> +     ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_STBY);
>> +     if (ret < 0) {
>> +             dev_err(&data->client->dev, "Error reading reg_stby\n");
>> +             return ret;
>> +     }
>> +     *mode = 0;
>> +
>> +     if (device & KMX61_ACC) {
>> +             if (ret & KMX61_ACC_STBY_BIT)
>> +                     *mode |= KMX61_ACC_STBY_BIT;
>> +             else
>> +                     *mode &= ~KMX61_ACC_STBY_BIT;
>> +     }
>> +
>> +     if (device & KMX61_MAG) {
>> +             if (ret & KMX61_MAG_STBY_BIT)
>> +                     *mode |= KMX61_MAG_STBY_BIT;
>> +             else
>> +                     *mode &= ~KMX61_MAG_STBY_BIT;
>> +     }
>> +
>> +     return 0;
>> +}
>> +
>> +static int kmx61_set_odr(struct kmx61_data *data, int val, int val2, u8 device)
>> +{
>> +     int ret;
>> +     u8 mode;
>> +     int lodr_bits, odr_bits;
>> +
>> +     ret = kmx61_get_mode(data, &mode, KMX61_ACC | KMX61_MAG);
>> +     if (ret < 0)
>> +             return ret;
>> +
>> +     lodr_bits = kmx61_convert_freq_to_bit(val, val2);
>> +     if (lodr_bits < 0)
>> +             return lodr_bits;
>> +
>> +     /* To change ODR, accel and magn must be in STDBY */
>> +     ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG);
>> +     if (ret < 0)
>> +             return ret;
>> +
>> +     odr_bits = 0;
>> +     if (device & KMX61_ACC)
>> +             odr_bits |= lodr_bits;
>> +     if (device & KMX61_MAG)
>> +             odr_bits |= (lodr_bits << KMX61_MAG_ODR_SHIFT);
>> +
>> +     ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_ODCNTL,
>> +                                     odr_bits);
>> +     if (ret < 0)
>> +             return ret;
>> +
>> +     ret = kmx61_set_mode(data, mode, KMX61_ACC | KMX61_MAG);
>> +     if (ret < 0)
>> +             return ret;
>> +
>> +     data->odr_bits = lodr_bits;
>> +
>> +     return 0;
>> +}
>> +
>> +static
>> +int kmx61_get_odr(struct kmx61_data *data, int *val, int *val2, u8 device)
>> +{    int i;
>> +     u8 lodr_bits;
>> +
>> +     if (device & KMX61_ACC)
>> +             lodr_bits = (data->odr_bits >> KMX61_ACC_ODR_SHIFT) &
>> +                          KMX61_ACC_ODR_MASK;
>> +     else if (device & KMX61_MAG)
>> +             lodr_bits = (data->odr_bits >> KMX61_MAG_ODR_SHIFT) &
>> +                          KMX61_MAG_ODR_MASK;
>> +     else
>> +             return -EINVAL;
>> +
>> +     for (i = 0; i < ARRAY_SIZE(samp_freq_table); i++)
>> +             if (lodr_bits == samp_freq_table[i].odr_bits) {
>> +                     *val = samp_freq_table[i].val;
>> +                     *val2 = samp_freq_table[i].val2;
>> +                     return 0;
>> +             }
>> +     return -EINVAL;
>> +}
>> +
>> +static int kmx61_set_range(struct kmx61_data *data, int range)
>> +{
>> +     int ret;
>> +
>> +     ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_CTRL1);
>> +     if (ret < 0) {
>> +             dev_err(&data->client->dev, "Error reading reg_ctrl1\n");
>> +             return ret;
>> +     }
>> +
>> +     ret &= ~(KMX61_REG_CTRL1_GSEL0_MASK | KMX61_REG_CTRL1_GSEL1_MASK);
>> +     ret |= kmx61_scale_table[range].gsel0 << KMX61_REG_CTRL1_GSEL0_SHIFT;
>> +     ret |= kmx61_scale_table[range].gsel1 << KMX61_REG_CTRL1_GSEL1_SHIFT;
>> +
>> +     ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_CTRL1, ret);
>> +     if (ret < 0) {
>> +             dev_err(&data->client->dev, "Error writing reg_ctrl1\n");
>> +             return ret;
>> +     }
>> +
>> +     data->range = range;
>> +
>> +     return 0;
>> +}
>> +
> I'd be tempted to use a parameter name other than val as that
> tends to have a fairly specific meaning in iio drivers
> (afterall you pass val2 in here!)  scale would work or
> maybe microscale or similar?

'scale' works for me. I will send a cleanup patch.

>> +static int kmx61_set_scale(struct kmx61_data *data, int val)
>> +{
>> +     int ret, i;
>> +     u8  mode;
>> +
>> +     for (i = 0; i < ARRAY_SIZE(kmx61_scale_table); i++) {
>> +             if (kmx61_scale_table[i].scale == val) {
>> +                     ret = kmx61_get_mode(data, &mode,
>> +                                          KMX61_ACC | KMX61_MAG);
>> +                     if (ret < 0)
>> +                             return ret;
>> +
>> +                     ret = kmx61_set_mode(data, KMX61_ALL_STBY,
>> +                                          KMX61_ACC | KMX61_MAG);
>> +                     if (ret < 0)
>> +                             return ret;
>> +
>> +                     ret = kmx61_set_range(data, i);
>> +                     if (ret < 0)
>> +                             return ret;
>> +
>> +                     ret = kmx61_set_mode(data, mode,
>> +                                          KMX61_ACC | KMX61_MAG);
>> +                     if (ret < 0)
>> +                             return ret;
>> +
>> +                     return 0;
>> +             }
>> +     }
>> +     return -EINVAL;
>> +}
>> +
>> +static int kmx61_chip_init(struct kmx61_data *data)
>> +{
>> +     int ret;
>> +
>> +     ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_WHO_AM_I);
>> +     if (ret < 0) {
>> +             dev_err(&data->client->dev, "Error reading who_am_i\n");
>> +             return ret;
>> +     }
>> +
>> +     if (ret != KMX61_CHIP_ID) {
>> +             dev_err(&data->client->dev,
>> +                     "Wrong chip id, got %x expected %x\n",
>> +                      ret, KMX61_CHIP_ID);
>> +             return -EINVAL;
>> +     }
>> +
>> +     /* set accel 12bit, 4g range */
>> +     ret = kmx61_set_range(data, KMX61_RANGE_4G);
>> +     if (ret < 0)
>> +             return ret;
>> +
>> +     /* put accel and magnetometer in operating mode */
>> +     ret = kmx61_set_mode(data, 0, KMX61_ACC | KMX61_MAG);
>> +     if (ret < 0)
>> +             return ret;
>> +
>> +     return 0;
>> +}
>> +
>> +static int kmx61_read_measurement(struct kmx61_data *data, int base, int offset)
>> +{
>> +     int ret;
>> +     u8 reg = base + offset * 2;
>> +
>> +     ret = i2c_smbus_read_word_data(data->client, reg);
>> +     if (ret < 0) {
>> +             dev_err(&data->client->dev, "failed to read reg at %x\n", reg);
>> +             return ret;
>> +     }
>> +
>> +     return ret;
>> +}
>> +
>> +static int kmx61_read_raw(struct iio_dev *indio_dev,
>> +                           struct iio_chan_spec const *chan, int *val,
>> +                           int *val2, long mask)
>> +{
>> +     struct kmx61_data *data = iio_priv(indio_dev);
>> +     int ret;
>> +     u8 base_reg;
>> +     u8 device;
>> +
>> +     switch (mask) {
>> +     case IIO_CHAN_INFO_RAW:
>> +             switch (chan->type) {
>> +             case IIO_ACCEL: case IIO_MAGN:
>> +                     base_reg = KMX61_ACC_XOUT_L;
>> +                     break;
>> +             default:
>> +                     return -EINVAL;
>> +             }
>> +             ret = kmx61_read_measurement(data, base_reg, chan->scan_index);
>> +             if (ret < 0)
>> +                     return ret;
>> +             *val = sign_extend32(ret >> chan->scan_type.shift,
>> +                                  chan->scan_type.realbits - 1);
>> +             return IIO_VAL_INT;
>> +     case IIO_CHAN_INFO_SCALE:
>> +             switch (chan->type) {
>> +             case IIO_ACCEL:
>> +                     *val = 0;
>> +                     *val2 = kmx61_scale_table[data->range].scale;
>> +                     return IIO_VAL_INT_PLUS_MICRO;
>> +             case IIO_MAGN:
>> +                     /* 14 bits res, 1465 microGauss per magn count */
>> +                     *val = 0;
>> +                     *val2 = 1465;
>> +                     return IIO_VAL_INT_PLUS_MICRO;
>> +             default:
>> +                     break;
>> +             }
>> +     case IIO_CHAN_INFO_SAMP_FREQ:
>> +             switch (chan->type) {
>> +             case IIO_ACCEL:
>> +                     device = KMX61_ACC;
>> +                     break;
>> +             case IIO_MAGN:
>> +                     device = KMX61_MAG;
>> +                     break;
>> +             default:
>> +                     return -EINVAL;
>> +             }
>> +
>> +             mutex_lock(&data->lock);
>> +             ret = kmx61_get_odr(data, val, val2, device);
>> +             mutex_unlock(&data->lock);
>> +             if (ret)
>> +                     return -EINVAL;
>> +             return IIO_VAL_INT_PLUS_MICRO;
>> +     }
>> +     return -EINVAL;
>> +}
>> +
>> +static int kmx61_write_raw(struct iio_dev *indio_dev,
>> +                            struct iio_chan_spec const *chan, int val,
>> +                            int val2, long mask)
>> +{
>> +     struct kmx61_data *data = iio_priv(indio_dev);
>> +     int ret;
>> +     u8 device;
>> +
>> +     switch (mask) {
>> +     case IIO_CHAN_INFO_SAMP_FREQ:
>> +             switch (chan->type) {
>> +             case IIO_ACCEL:
>> +                     device = KMX61_ACC;
>> +                     break;
>> +             case IIO_MAGN:
>> +                     device = KMX61_MAG;
>> +                     break;
>> +             default:
>> +                     return -EINVAL;
>> +             }
>> +             mutex_lock(&data->lock);
>> +             ret = kmx61_set_odr(data, val, val2, device);
>> +             mutex_unlock(&data->lock);
>> +             break;
>> +     case IIO_CHAN_INFO_SCALE:
>> +             switch (chan->type) {
>> +             case IIO_ACCEL:
>
> Should verify that val == 0 incase of crazy userspace input.

Looks good. Thanks for updating the patch.

>> +                     mutex_lock(&data->lock);
>> +                     ret = kmx61_set_scale(data, val2);
>> +                     mutex_unlock(&data->lock);
>> +                     break;
>> +             default:
>> +                     ret  = -EINVAL;
>> +             }
>> +             break;
>> +     default:
>> +             ret = -EINVAL;
>> +     }
>> +
>> +     return ret;
>> +}
>> +
>> +static const struct iio_info kmx61_info = {
>> +     .driver_module          = THIS_MODULE,
>> +     .read_raw               = kmx61_read_raw,
>> +     .write_raw              = kmx61_write_raw,
>> +     .attrs                  = &kmx61_attribute_group,
>> +};
>> +
>> +static int kmx61_probe(struct i2c_client *client,
>> +                    const struct i2c_device_id *id)
>> +{
>> +     struct kmx61_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;
>> +
>> +     indio_dev->dev.parent = &client->dev;
>> +     indio_dev->info = &kmx61_info;
>> +     indio_dev->channels = kmx61_channels;
>> +     indio_dev->num_channels = ARRAY_SIZE(kmx61_channels);
>> +     indio_dev->modes = INDIO_DIRECT_MODE;
>> +
>> +     mutex_init(&data->lock);
>> +
>> +     ret = kmx61_chip_init(data);
>> +     if (ret < 0)
>> +             return ret;
>> +
>> +     return iio_device_register(indio_dev);
>> +}
>> +
>> +static int kmx61_remove(struct i2c_client *client)
>> +{
>> +     struct iio_dev *indio_dev = i2c_get_clientdata(client);
>> +     struct kmx61_data *data = iio_priv(indio_dev);
>> +     int ret;
>> +
>> +     iio_device_unregister(indio_dev);
>> +
>> +     mutex_lock(&data->lock);
>> +     ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG);
>> +     mutex_unlock(&data->lock);
>> +
>> +     return ret;
>> +}
>> +
>> +static const struct i2c_device_id kmx61_id[] = {
>> +     {"kmx61", 0},
>> +     {}
>> +};
>> +
>> +MODULE_DEVICE_TABLE(i2c, kmx61_id);
>> +
>> +static struct i2c_driver kmx61_driver = {
>> +     .driver = {
>> +             .name = "kmx61",
>> +     },
>> +     .probe          = kmx61_probe,
>> +     .remove         = kmx61_remove,
>> +     .id_table       = kmx61_id,
>> +};
>> +
>> +module_i2c_driver(kmx61_driver);
>> +
>> +MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
>> +MODULE_DESCRIPTION("KMX61 accelerometer/magnetometer driver");
>> +MODULE_LICENSE("GPL v2");
>>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-iio" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v2] iio: imu: Add support for Kionix KMX61 sensor
  2014-11-10 17:24 [PATCH v2] iio: imu: Add support for Kionix KMX61 sensor Daniel Baluta
  2014-11-16 21:10 ` Jonathan Cameron
@ 2014-11-17 13:46 ` Peter Meerwald
  2014-11-17 15:24   ` Daniel Baluta
  1 sibling, 1 reply; 6+ messages in thread
From: Peter Meerwald @ 2014-11-17 13:46 UTC (permalink / raw)
  To: Daniel Baluta; +Cc: jic23, linux-iio, srinivas.pandruvada, linux-kernel


> Minimal implementation for KMX61 6-axis accelerometer/magnetometer. It exports
> raw accel/magn readings together with scale and sampling frequency.
> 
> Datasheet will be available at:
> http://www.kionix.com/6-axis-accelerometer-magnetometer/kmx61

some trivial comments below
 
> Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
> ---
> Changes since v1:
> 	* serialize non-atomic operations with a mutex (set_odr/get_odr, set_scale).
> 	* no need to protect reading info scale because it reduces to reading an u8
> 	which should be atomic on all arches
> 	* *note* - read_measurment is an atomic operation
> 	
>  drivers/iio/imu/Kconfig  |   9 +
>  drivers/iio/imu/Makefile |   2 +
>  drivers/iio/imu/kmx61.c  | 590 +++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 601 insertions(+)
>  create mode 100644 drivers/iio/imu/kmx61.c
> 
> diff --git a/drivers/iio/imu/Kconfig b/drivers/iio/imu/Kconfig
> index 2b0e451..d675f43 100644
> --- a/drivers/iio/imu/Kconfig
> +++ b/drivers/iio/imu/Kconfig
> @@ -25,6 +25,15 @@ config ADIS16480
>  	  Say yes here to build support for Analog Devices ADIS16375, ADIS16480,
>  	  ADIS16485, ADIS16488 inertial sensors.
>  
> +config KMX61
> +	tristate "Kionix KMX61 6-axis accelerometer and magnetometer"
> +	depends on I2C
> +	help
> +	  Say Y here if you want to build a driver for Kionix KMX61 6-axis accelerometer
> +	  and magnetometer.
> +	  To compile this driver as module, choose M here: the module will be called
> +	  kmx61.
> +
>  source "drivers/iio/imu/inv_mpu6050/Kconfig"
>  
>  endmenu
> diff --git a/drivers/iio/imu/Makefile b/drivers/iio/imu/Makefile
> index 114d2c1..e1e6e3d 100644
> --- a/drivers/iio/imu/Makefile
> +++ b/drivers/iio/imu/Makefile
> @@ -14,3 +14,5 @@ adis_lib-$(CONFIG_IIO_ADIS_LIB_BUFFER) += adis_buffer.o
>  obj-$(CONFIG_IIO_ADIS_LIB) += adis_lib.o
>  
>  obj-y += inv_mpu6050/
> +
> +obj-$(CONFIG_KMX61) += kmx61.o
> diff --git a/drivers/iio/imu/kmx61.c b/drivers/iio/imu/kmx61.c
> new file mode 100644
> index 0000000..6135a16
> --- /dev/null
> +++ b/drivers/iio/imu/kmx61.c
> @@ -0,0 +1,590 @@
> +/*
> + * KMX61 - Kionix 6-axis Accelerometer/Magnetometer
> + *
> + * Copyright (c) 2014, Intel Corporation.
> + *
> + * This file is subject to the terms and conditions of version 2 of
> + * the GNU General Public License.  See the file COPYING in the main
> + * directory of this archive for more details.
> + *
> + * IIO driver for KMX61 (7-bit I2C slave address 0x0E or 0x0F).
> + *
> + * TODO: buffer, interrupt, thresholds, acpi, temperature sensor
> + *
> + */
> +
> +#include <linux/module.h>
> +#include <linux/i2c.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +
> +#define KMX61_DRV_NAME "kmx61"
> +
> +#define KMX61_REG_WHO_AM_I		0x00
> +
> +#define KMX61_ACC_XOUT_L		0x0A
> +
> +#define KMX61_ACC_XOUT_H		0x0B
> +#define KMX61_ACC_YOUT_L		0x0C
> +#define KMX61_ACC_YOUT_H		0x0D
> +#define KMX61_ACC_ZOUT_L		0x0E
> +#define KMX61_ACC_ZOUT_H		0x0F
> +
> +#define KMX61_MAG_XOUT_L		0x12
> +
> +#define KMX61_MAG_XOUT_H		0x13
> +#define KMX61_MAG_YOUT_L		0x14
> +#define KMX61_MAG_YOUT_H		0x15
> +#define KMX61_MAG_ZOUT_L		0x16
> +#define KMX61_MAG_ZOUT_H		0x17

only the XOUT_L #defines are actually used, there is extra whitespace

I'd suggest to drop the other defines and maybe add a comment 
saying that we have 3 16-bit LSB values for X/Y/Z

> +
> +#define KMX61_REG_ODCNTL		0x2C
> +
> +#define KMX61_REG_STBY			0x29
> +#define KMX61_REG_CTRL1			0x2A
> +
> +#define KMX61_REG_COTR			0x3C
> +
> +#define KMX61_ACC_STBY_BIT	BIT(0)
> +#define KMX61_MAG_STBY_BIT	BIT(1)
> +#define KMX61_ACT_STBY_BIT	BIT(7)
> +
> +#define KMX61_ALL_STBY		(KMX61_ACC_STBY_BIT | KMX61_MAG_STBY_BIT)
> +
> +#define KMX61_REG_CTRL1_GSEL0_SHIFT	0
> +#define KMX61_REG_CTRL1_GSEL1_SHIFT	1
> +#define KMX61_REG_CTRL1_GSEL0_MASK	0x01
> +#define KMX61_REG_CTRL1_GSEL1_MASK	0x02
> +
> +#define KMX61_REG_CTRL1_BIT_RES		BIT(4)
> +
> +#define KMX61_ACC_ODR_SHIFT	0
> +#define KMX61_MAG_ODR_SHIFT	4
> +#define KMX61_ACC_ODR_MASK	0x0F
> +#define KMX61_MAG_ODR_MASK	0xF0
> +
> +#define KMX61_CHIP_ID		0x12
> +
> +struct kmx61_data {
> +	struct i2c_client *client;
> +	/* serialize access to non-atomic ops, e.g set_mode */
> +	struct mutex lock;
> +	u8 range;
> +	u8 odr_bits;
> +};
> +
> +enum kmx61_range {
> +	KMX61_RANGE_2G,
> +	KMX61_RANGE_4G,
> +	KMX61_RANGE_8G,
> +};
> +
> +enum kmx61_scan {
> +	KMX61_SCAN_ACC_X,
> +	KMX61_SCAN_ACC_Y,
> +	KMX61_SCAN_ACC_Z,
> +	KMX61_SCAN_TEMP,
> +	KMX61_SCAN_MAG_X,
> +	KMX61_SCAN_MAG_Y,
> +	KMX61_SCAN_MAG_Z,
> +};
> +
> +static const struct {
> +	u16 scale;
> +	u8 gsel0;
> +	u8 gsel1;
> +} kmx61_scale_table[] = {
> +	{9582, 0, 0},
> +	{19163, 1, 0},
> +	{38326, 0, 1},
> +};
> +
> +/* KMX61 devices */
> +#define KMX61_ACC	0x01
> +#define KMX61_MAG	0x02
> +
> +static const struct {
> +	int val;
> +	int val2;
> +	int odr_bits;

odr_bits should probably be u8

> +} samp_freq_table[] = { {12, 500000, 0x00},

no kmx16_ prefix

> +			{25, 0, 0x01},
> +			{50, 0, 0x02},
> +			{100, 0, 0x03},
> +			{200, 0, 0x04},
> +			{400, 0, 0x05},
> +			{800, 0, 0x06},
> +			{1600, 0, 0x07},
> +			{0, 781000, 0x08},
> +			{1, 563000, 0x09},
> +			{3, 125000, 0x0A},
> +			{6, 250000, 0x0B} };
> +
> +static IIO_CONST_ATTR(accel_scale_available, "0.009582 0.019163 0.038326");
> +static IIO_CONST_ATTR(magn_scale_available, "0.001465");
> +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
> +	"0.781000 1.563000 3.125000 6.250000 12.500000 25 50 100 200 400 800");
> +
> +static struct attribute *kmx61_attributes[] = {
> +	&iio_const_attr_accel_scale_available.dev_attr.attr,
> +	&iio_const_attr_magn_scale_available.dev_attr.attr,
> +	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
> +	NULL,
> +};
> +
> +static const struct attribute_group kmx61_attribute_group = {
> +	.attrs = kmx61_attributes,
> +};
> +
> +#define KMX61_ACC_CHAN(_axis, _index) { \
> +	.type = IIO_ACCEL, \
> +	.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 = _index, \
> +	.scan_type = { \
> +		.sign = 's', \
> +		.realbits = 12, \
> +		.storagebits = 16, \
> +		.shift = 4, \
> +		.endianness = IIO_BE, \

the data registers are LSB, so it should be IIO_LE
buffering is not implemented, so it doesn't matter; but IIO_BE is 
definitely wrong

> +	}, \
> +}
> +
> +#define KMX61_MAG_CHAN(_axis, _index) { \
> +	.type = IIO_MAGN, \
> +	.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 = _index, \
> +	.scan_type = { \
> +		.sign = 's', \
> +		.realbits = 14, \
> +		.storagebits = 16, \
> +		.shift = 2, \
> +		.endianness = IIO_BE, \
> +	}, \
> +}
> +
> +static const struct iio_chan_spec kmx61_channels[] = {
> +	KMX61_ACC_CHAN(X, KMX61_SCAN_ACC_X),
> +	KMX61_ACC_CHAN(Y, KMX61_SCAN_ACC_Y),
> +	KMX61_ACC_CHAN(Z, KMX61_SCAN_ACC_Z),
> +	KMX61_MAG_CHAN(X, KMX61_SCAN_MAG_X),
> +	KMX61_MAG_CHAN(Y, KMX61_SCAN_MAG_Y),
> +	KMX61_MAG_CHAN(Z, KMX61_SCAN_MAG_Z),
> +};
> +
> +static int kmx61_convert_freq_to_bit(int val, int val2)
> +{
> +	int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(samp_freq_table); i++)
> +		if (val == samp_freq_table[i].val &&
> +		    val2 == samp_freq_table[i].val2)
> +			return samp_freq_table[i].odr_bits;
> +	return -EINVAL;
> +}
> +
> +static int kmx61_set_mode(struct kmx61_data *data, u8 mode, u8 device)
> +{
> +	int ret;
> +
> +	ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_STBY);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error reading reg_stby\n");
> +		return ret;
> +	}
> +	if (device & KMX61_ACC) {
> +		if (mode & KMX61_ACC_STBY_BIT)
> +			ret |= KMX61_ACC_STBY_BIT;
> +		else
> +			ret &= ~KMX61_ACC_STBY_BIT;
> +	}
> +
> +	if (device & KMX61_MAG) {
> +		if (mode & KMX61_MAG_STBY_BIT)
> +			ret |= KMX61_MAG_STBY_BIT;
> +		else
> +			ret &= ~KMX61_MAG_STBY_BIT;
> +	}
> +
> +	ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_STBY, ret);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error writing reg_stby\n");
> +		return ret;
> +	}
> +
> +	return ret;
> +}
> +
> +static int kmx61_get_mode(struct kmx61_data *data, u8 *mode, u8 device)
> +{
> +	int ret;
> +
> +	ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_STBY);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error reading reg_stby\n");
> +		return ret;
> +	}
> +	*mode = 0;
> +
> +	if (device & KMX61_ACC) {
> +		if (ret & KMX61_ACC_STBY_BIT)
> +			*mode |= KMX61_ACC_STBY_BIT;
> +		else
> +			*mode &= ~KMX61_ACC_STBY_BIT;
> +	}
> +
> +	if (device & KMX61_MAG) {
> +		if (ret & KMX61_MAG_STBY_BIT)
> +			*mode |= KMX61_MAG_STBY_BIT;
> +		else
> +			*mode &= ~KMX61_MAG_STBY_BIT;
> +	}
> +
> +	return 0;
> +}
> +
> +static int kmx61_set_odr(struct kmx61_data *data, int val, int val2, u8 device)
> +{
> +	int ret;
> +	u8 mode;
> +	int lodr_bits, odr_bits;
> +
> +	ret = kmx61_get_mode(data, &mode, KMX61_ACC | KMX61_MAG);
> +	if (ret < 0)
> +		return ret;
> +
> +	lodr_bits = kmx61_convert_freq_to_bit(val, val2);
> +	if (lodr_bits < 0)
> +		return lodr_bits;
> +
> +	/* To change ODR, accel and magn must be in STDBY */
> +	ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG);
> +	if (ret < 0)
> +		return ret;
> +
> +	odr_bits = 0;
> +	if (device & KMX61_ACC)
> +		odr_bits |= lodr_bits;
> +	if (device & KMX61_MAG)
> +		odr_bits |= (lodr_bits << KMX61_MAG_ODR_SHIFT);
> +
> +	ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_ODCNTL,
> +					odr_bits);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = kmx61_set_mode(data, mode, KMX61_ACC | KMX61_MAG);
> +	if (ret < 0)
> +		return ret;
> +
> +	data->odr_bits = lodr_bits;
> +
> +	return 0;
> +}
> +
> +static
> +int kmx61_get_odr(struct kmx61_data *data, int *val, int *val2, u8 device)
> +{	int i;
> +	u8 lodr_bits;
> +
> +	if (device & KMX61_ACC)
> +		lodr_bits = (data->odr_bits >> KMX61_ACC_ODR_SHIFT) &
> +			     KMX61_ACC_ODR_MASK;
> +	else if (device & KMX61_MAG)
> +		lodr_bits = (data->odr_bits >> KMX61_MAG_ODR_SHIFT) &
> +			     KMX61_MAG_ODR_MASK;
> +	else
> +		return -EINVAL;
> +
> +	for (i = 0; i < ARRAY_SIZE(samp_freq_table); i++)
> +		if (lodr_bits == samp_freq_table[i].odr_bits) {
> +			*val = samp_freq_table[i].val;
> +			*val2 = samp_freq_table[i].val2;
> +			return 0;
> +		}
> +	return -EINVAL;
> +}
> +
> +static int kmx61_set_range(struct kmx61_data *data, int range)
> +{
> +	int ret;
> +
> +	ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_CTRL1);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error reading reg_ctrl1\n");
> +		return ret;
> +	}
> +
> +	ret &= ~(KMX61_REG_CTRL1_GSEL0_MASK | KMX61_REG_CTRL1_GSEL1_MASK);
> +	ret |= kmx61_scale_table[range].gsel0 << KMX61_REG_CTRL1_GSEL0_SHIFT;
> +	ret |= kmx61_scale_table[range].gsel1 << KMX61_REG_CTRL1_GSEL1_SHIFT;
> +
> +	ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_CTRL1, ret);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error writing reg_ctrl1\n");
> +		return ret;
> +	}
> +
> +	data->range = range;
> +
> +	return 0;
> +}
> +
> +static int kmx61_set_scale(struct kmx61_data *data, int val)
> +{
> +	int ret, i;
> +	u8  mode;
> +
> +	for (i = 0; i < ARRAY_SIZE(kmx61_scale_table); i++) {
> +		if (kmx61_scale_table[i].scale == val) {
> +			ret = kmx61_get_mode(data, &mode,
> +					     KMX61_ACC | KMX61_MAG);
> +			if (ret < 0)
> +				return ret;
> +
> +			ret = kmx61_set_mode(data, KMX61_ALL_STBY,
> +					     KMX61_ACC | KMX61_MAG);
> +			if (ret < 0)
> +				return ret;
> +
> +			ret = kmx61_set_range(data, i);
> +			if (ret < 0)
> +				return ret;
> +
> +			ret = kmx61_set_mode(data, mode,
> +					     KMX61_ACC | KMX61_MAG);

simply return here

> +			if (ret < 0)
> +				return ret;
> +
> +			return 0;
> +		}
> +	}
> +	return -EINVAL;
> +}
> +
> +static int kmx61_chip_init(struct kmx61_data *data)
> +{
> +	int ret;
> +
> +	ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_WHO_AM_I);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "Error reading who_am_i\n");
> +		return ret;
> +	}
> +
> +	if (ret != KMX61_CHIP_ID) {
> +		dev_err(&data->client->dev,
> +			"Wrong chip id, got %x expected %x\n",
> +			 ret, KMX61_CHIP_ID);
> +		return -EINVAL;
> +	}
> +
> +	/* set accel 12bit, 4g range */
> +	ret = kmx61_set_range(data, KMX61_RANGE_4G);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* put accel and magnetometer in operating mode */
> +	ret = kmx61_set_mode(data, 0, KMX61_ACC | KMX61_MAG);
> +	if (ret < 0)
> +		return ret;
> +
> +	return 0;
> +}
> +
> +static int kmx61_read_measurement(struct kmx61_data *data, int base, int offset)
> +{
> +	int ret;
> +	u8 reg = base + offset * 2;
> +
> +	ret = i2c_smbus_read_word_data(data->client, reg);
> +	if (ret < 0) {
> +		dev_err(&data->client->dev, "failed to read reg at %x\n", reg);
> +		return ret;
> +	}
> +
> +	return ret;
> +}
> +
> +static int kmx61_read_raw(struct iio_dev *indio_dev,
> +			      struct iio_chan_spec const *chan, int *val,
> +			      int *val2, long mask)
> +{
> +	struct kmx61_data *data = iio_priv(indio_dev);
> +	int ret;
> +	u8 base_reg;
> +	u8 device;
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		switch (chan->type) {
> +		case IIO_ACCEL: case IIO_MAGN:

cases on separate lines would be more readable

> +			base_reg = KMX61_ACC_XOUT_L;
> +			break;
> +		default:
> +			return -EINVAL;
> +		}
> +		ret = kmx61_read_measurement(data, base_reg, chan->scan_index);
> +		if (ret < 0)
> +			return ret;
> +		*val = sign_extend32(ret >> chan->scan_type.shift,
> +				     chan->scan_type.realbits - 1);
> +		return IIO_VAL_INT;
> +	case IIO_CHAN_INFO_SCALE:
> +		switch (chan->type) {
> +		case IIO_ACCEL:
> +			*val = 0;
> +			*val2 = kmx61_scale_table[data->range].scale;
> +			return IIO_VAL_INT_PLUS_MICRO;
> +		case IIO_MAGN:
> +			/* 14 bits res, 1465 microGauss per magn count */
> +			*val = 0;
> +			*val2 = 1465;
> +			return IIO_VAL_INT_PLUS_MICRO;
> +		default:

could just return -EINVAL here

> +			break;
> +		}
> +	case IIO_CHAN_INFO_SAMP_FREQ:
> +		switch (chan->type) {
> +		case IIO_ACCEL:
> +			device = KMX61_ACC;
> +			break;
> +		case IIO_MAGN:
> +			device = KMX61_MAG;
> +			break;
> +		default:
> +			return -EINVAL;
> +		}
> +
> +		mutex_lock(&data->lock);
> +		ret = kmx61_get_odr(data, val, val2, device);
> +		mutex_unlock(&data->lock);
> +		if (ret)
> +			return -EINVAL;
> +		return IIO_VAL_INT_PLUS_MICRO;
> +	}
> +	return -EINVAL;
> +}
> +
> +static int kmx61_write_raw(struct iio_dev *indio_dev,
> +			       struct iio_chan_spec const *chan, int val,
> +			       int val2, long mask)
> +{
> +	struct kmx61_data *data = iio_priv(indio_dev);
> +	int ret;
> +	u8 device;
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_SAMP_FREQ:

you could use chan->address to store the device type (ACC or MAG) and save 
the switch block (here and in other places)

> +		switch (chan->type) {
> +		case IIO_ACCEL:
> +			device = KMX61_ACC;
> +			break;
> +		case IIO_MAGN:
> +			device = KMX61_MAG;
> +			break;
> +		default:
> +			return -EINVAL;
> +		}
> +		mutex_lock(&data->lock);
> +		ret = kmx61_set_odr(data, val, val2, device);
> +		mutex_unlock(&data->lock);

follow edits are a matter of taste :)

return ret;

> +		break;
> +	case IIO_CHAN_INFO_SCALE:
> +		switch (chan->type) {
> +		case IIO_ACCEL:
> +			mutex_lock(&data->lock);
> +			ret = kmx61_set_scale(data, val2);
> +			mutex_unlock(&data->lock);
> +			break;
> +		default:
> +			ret  = -EINVAL;

return -EINVAL

> +		}

return ret;

> +		break;
> +	default:

return -EINVAL;


> +		ret = -EINVAL;
> +	}
> +
> +	return ret;
> +}
> +
> +static const struct iio_info kmx61_info = {
> +	.driver_module		= THIS_MODULE,
> +	.read_raw		= kmx61_read_raw,
> +	.write_raw		= kmx61_write_raw,
> +	.attrs			= &kmx61_attribute_group,
> +};
> +
> +static int kmx61_probe(struct i2c_client *client,
> +		       const struct i2c_device_id *id)
> +{
> +	struct kmx61_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;
> +
> +	indio_dev->dev.parent = &client->dev;
> +	indio_dev->info = &kmx61_info;

set indio_dev->name?

> +	indio_dev->channels = kmx61_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(kmx61_channels);
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +
> +	mutex_init(&data->lock);
> +
> +	ret = kmx61_chip_init(data);
> +	if (ret < 0)
> +		return ret;
> +
> +	return iio_device_register(indio_dev);
> +}
> +
> +static int kmx61_remove(struct i2c_client *client)
> +{
> +	struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +	struct kmx61_data *data = iio_priv(indio_dev);
> +	int ret;
> +
> +	iio_device_unregister(indio_dev);
> +
> +	mutex_lock(&data->lock);
> +	ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG);
> +	mutex_unlock(&data->lock);
> +
> +	return ret;
> +}
> +
> +static const struct i2c_device_id kmx61_id[] = {
> +	{"kmx61", 0},
> +	{}
> +};
> +
> +MODULE_DEVICE_TABLE(i2c, kmx61_id);
> +
> +static struct i2c_driver kmx61_driver = {
> +	.driver = {
> +		.name = "kmx61",
> +	},
> +	.probe		= kmx61_probe,
> +	.remove		= kmx61_remove,
> +	.id_table	= kmx61_id,
> +};
> +
> +module_i2c_driver(kmx61_driver);
> +
> +MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
> +MODULE_DESCRIPTION("KMX61 accelerometer/magnetometer driver");
> +MODULE_LICENSE("GPL v2");
> 

-- 

Peter Meerwald
+43-664-2444418 (mobile)

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v2] iio: imu: Add support for Kionix KMX61 sensor
  2014-11-17 13:46 ` Peter Meerwald
@ 2014-11-17 15:24   ` Daniel Baluta
  0 siblings, 0 replies; 6+ messages in thread
From: Daniel Baluta @ 2014-11-17 15:24 UTC (permalink / raw)
  To: Peter Meerwald
  Cc: Daniel Baluta, Jonathan Cameron, linux-iio, Srinivas Pandruvada,
	Linux Kernel Mailing List

On Mon, Nov 17, 2014 at 3:46 PM, Peter Meerwald <pmeerw@pmeerw.net> wrote:
>
>> Minimal implementation for KMX61 6-axis accelerometer/magnetometer. It exports
>> raw accel/magn readings together with scale and sampling frequency.
>>
>> Datasheet will be available at:
>> http://www.kionix.com/6-axis-accelerometer-magnetometer/kmx61
>
> some trivial comments below
>
>> Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
>> ---
>> Changes since v1:
>>       * serialize non-atomic operations with a mutex (set_odr/get_odr, set_scale).
>>       * no need to protect reading info scale because it reduces to reading an u8
>>       which should be atomic on all arches
>>       * *note* - read_measurment is an atomic operation
>>
>>  drivers/iio/imu/Kconfig  |   9 +
>>  drivers/iio/imu/Makefile |   2 +
>>  drivers/iio/imu/kmx61.c  | 590 +++++++++++++++++++++++++++++++++++++++++++++++
>>  3 files changed, 601 insertions(+)
>>  create mode 100644 drivers/iio/imu/kmx61.c
>>
>> diff --git a/drivers/iio/imu/Kconfig b/drivers/iio/imu/Kconfig
>> index 2b0e451..d675f43 100644
>> --- a/drivers/iio/imu/Kconfig
>> +++ b/drivers/iio/imu/Kconfig
>> @@ -25,6 +25,15 @@ config ADIS16480
>>         Say yes here to build support for Analog Devices ADIS16375, ADIS16480,
>>         ADIS16485, ADIS16488 inertial sensors.
>>
>> +config KMX61
>> +     tristate "Kionix KMX61 6-axis accelerometer and magnetometer"
>> +     depends on I2C
>> +     help
>> +       Say Y here if you want to build a driver for Kionix KMX61 6-axis accelerometer
>> +       and magnetometer.
>> +       To compile this driver as module, choose M here: the module will be called
>> +       kmx61.
>> +
>>  source "drivers/iio/imu/inv_mpu6050/Kconfig"
>>
>>  endmenu
>> diff --git a/drivers/iio/imu/Makefile b/drivers/iio/imu/Makefile
>> index 114d2c1..e1e6e3d 100644
>> --- a/drivers/iio/imu/Makefile
>> +++ b/drivers/iio/imu/Makefile
>> @@ -14,3 +14,5 @@ adis_lib-$(CONFIG_IIO_ADIS_LIB_BUFFER) += adis_buffer.o
>>  obj-$(CONFIG_IIO_ADIS_LIB) += adis_lib.o
>>
>>  obj-y += inv_mpu6050/
>> +
>> +obj-$(CONFIG_KMX61) += kmx61.o
>> diff --git a/drivers/iio/imu/kmx61.c b/drivers/iio/imu/kmx61.c
>> new file mode 100644
>> index 0000000..6135a16
>> --- /dev/null
>> +++ b/drivers/iio/imu/kmx61.c
>> @@ -0,0 +1,590 @@
>> +/*
>> + * KMX61 - Kionix 6-axis Accelerometer/Magnetometer
>> + *
>> + * Copyright (c) 2014, Intel Corporation.
>> + *
>> + * This file is subject to the terms and conditions of version 2 of
>> + * the GNU General Public License.  See the file COPYING in the main
>> + * directory of this archive for more details.
>> + *
>> + * IIO driver for KMX61 (7-bit I2C slave address 0x0E or 0x0F).
>> + *
>> + * TODO: buffer, interrupt, thresholds, acpi, temperature sensor
>> + *
>> + */
>> +
>> +#include <linux/module.h>
>> +#include <linux/i2c.h>
>> +#include <linux/iio/iio.h>
>> +#include <linux/iio/sysfs.h>
>> +
>> +#define KMX61_DRV_NAME "kmx61"
>> +
>> +#define KMX61_REG_WHO_AM_I           0x00
>> +
>> +#define KMX61_ACC_XOUT_L             0x0A
>> +
>> +#define KMX61_ACC_XOUT_H             0x0B
>> +#define KMX61_ACC_YOUT_L             0x0C
>> +#define KMX61_ACC_YOUT_H             0x0D
>> +#define KMX61_ACC_ZOUT_L             0x0E
>> +#define KMX61_ACC_ZOUT_H             0x0F
>> +
>> +#define KMX61_MAG_XOUT_L             0x12
>> +
>> +#define KMX61_MAG_XOUT_H             0x13
>> +#define KMX61_MAG_YOUT_L             0x14
>> +#define KMX61_MAG_YOUT_H             0x15
>> +#define KMX61_MAG_ZOUT_L             0x16
>> +#define KMX61_MAG_ZOUT_H             0x17
>
> only the XOUT_L #defines are actually used, there is extra whitespace
>
> I'd suggest to drop the other defines and maybe add a comment
> saying that we have 3 16-bit LSB values for X/Y/Z

I added all these defines for documentation, in the same way
accel/kxcjk-1013.c did.

I think its better to add a comment making this clear.

>
>> +
>> +#define KMX61_REG_ODCNTL             0x2C
>> +
>> +#define KMX61_REG_STBY                       0x29
>> +#define KMX61_REG_CTRL1                      0x2A
>> +
>> +#define KMX61_REG_COTR                       0x3C
>> +
>> +#define KMX61_ACC_STBY_BIT   BIT(0)
>> +#define KMX61_MAG_STBY_BIT   BIT(1)
>> +#define KMX61_ACT_STBY_BIT   BIT(7)
>> +
>> +#define KMX61_ALL_STBY               (KMX61_ACC_STBY_BIT | KMX61_MAG_STBY_BIT)
>> +
>> +#define KMX61_REG_CTRL1_GSEL0_SHIFT  0
>> +#define KMX61_REG_CTRL1_GSEL1_SHIFT  1
>> +#define KMX61_REG_CTRL1_GSEL0_MASK   0x01
>> +#define KMX61_REG_CTRL1_GSEL1_MASK   0x02
>> +
>> +#define KMX61_REG_CTRL1_BIT_RES              BIT(4)
>> +
>> +#define KMX61_ACC_ODR_SHIFT  0
>> +#define KMX61_MAG_ODR_SHIFT  4
>> +#define KMX61_ACC_ODR_MASK   0x0F
>> +#define KMX61_MAG_ODR_MASK   0xF0
>> +
>> +#define KMX61_CHIP_ID                0x12
>> +
>> +struct kmx61_data {
>> +     struct i2c_client *client;
>> +     /* serialize access to non-atomic ops, e.g set_mode */
>> +     struct mutex lock;
>> +     u8 range;
>> +     u8 odr_bits;
>> +};
>> +
>> +enum kmx61_range {
>> +     KMX61_RANGE_2G,
>> +     KMX61_RANGE_4G,
>> +     KMX61_RANGE_8G,
>> +};
>> +
>> +enum kmx61_scan {
>> +     KMX61_SCAN_ACC_X,
>> +     KMX61_SCAN_ACC_Y,
>> +     KMX61_SCAN_ACC_Z,
>> +     KMX61_SCAN_TEMP,
>> +     KMX61_SCAN_MAG_X,
>> +     KMX61_SCAN_MAG_Y,
>> +     KMX61_SCAN_MAG_Z,
>> +};
>> +
>> +static const struct {
>> +     u16 scale;
>> +     u8 gsel0;
>> +     u8 gsel1;
>> +} kmx61_scale_table[] = {
>> +     {9582, 0, 0},
>> +     {19163, 1, 0},
>> +     {38326, 0, 1},
>> +};
>> +
>> +/* KMX61 devices */
>> +#define KMX61_ACC    0x01
>> +#define KMX61_MAG    0x02
>> +
>> +static const struct {
>> +     int val;
>> +     int val2;
>> +     int odr_bits;
>
> odr_bits should probably be u8
>
>> +} samp_freq_table[] = { {12, 500000, 0x00},
>
> no kmx16_ prefix

Correct. Will fix.

>
>> +                     {25, 0, 0x01},
>> +                     {50, 0, 0x02},
>> +                     {100, 0, 0x03},
>> +                     {200, 0, 0x04},
>> +                     {400, 0, 0x05},
>> +                     {800, 0, 0x06},
>> +                     {1600, 0, 0x07},
>> +                     {0, 781000, 0x08},
>> +                     {1, 563000, 0x09},
>> +                     {3, 125000, 0x0A},
>> +                     {6, 250000, 0x0B} };
>> +
>> +static IIO_CONST_ATTR(accel_scale_available, "0.009582 0.019163 0.038326");
>> +static IIO_CONST_ATTR(magn_scale_available, "0.001465");
>> +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
>> +     "0.781000 1.563000 3.125000 6.250000 12.500000 25 50 100 200 400 800");
>> +
>> +static struct attribute *kmx61_attributes[] = {
>> +     &iio_const_attr_accel_scale_available.dev_attr.attr,
>> +     &iio_const_attr_magn_scale_available.dev_attr.attr,
>> +     &iio_const_attr_sampling_frequency_available.dev_attr.attr,
>> +     NULL,
>> +};
>> +
>> +static const struct attribute_group kmx61_attribute_group = {
>> +     .attrs = kmx61_attributes,
>> +};
>> +
>> +#define KMX61_ACC_CHAN(_axis, _index) { \
>> +     .type = IIO_ACCEL, \
>> +     .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 = _index, \
>> +     .scan_type = { \
>> +             .sign = 's', \
>> +             .realbits = 12, \
>> +             .storagebits = 16, \
>> +             .shift = 4, \
>> +             .endianness = IIO_BE, \
>
> the data registers are LSB, so it should be IIO_LE
> buffering is not implemented, so it doesn't matter; but IIO_BE is
> definitely wrong
>
Ok. Will fix.

>> +     }, \
>> +}
>> +
>> +#define KMX61_MAG_CHAN(_axis, _index) { \
>> +     .type = IIO_MAGN, \
>> +     .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 = _index, \
>> +     .scan_type = { \
>> +             .sign = 's', \
>> +             .realbits = 14, \
>> +             .storagebits = 16, \
>> +             .shift = 2, \
>> +             .endianness = IIO_BE, \
>> +     }, \
>> +}
>> +
>> +static const struct iio_chan_spec kmx61_channels[] = {
>> +     KMX61_ACC_CHAN(X, KMX61_SCAN_ACC_X),
>> +     KMX61_ACC_CHAN(Y, KMX61_SCAN_ACC_Y),
>> +     KMX61_ACC_CHAN(Z, KMX61_SCAN_ACC_Z),
>> +     KMX61_MAG_CHAN(X, KMX61_SCAN_MAG_X),
>> +     KMX61_MAG_CHAN(Y, KMX61_SCAN_MAG_Y),
>> +     KMX61_MAG_CHAN(Z, KMX61_SCAN_MAG_Z),
>> +};
>> +
>> +static int kmx61_convert_freq_to_bit(int val, int val2)
>> +{
>> +     int i;
>> +
>> +     for (i = 0; i < ARRAY_SIZE(samp_freq_table); i++)
>> +             if (val == samp_freq_table[i].val &&
>> +                 val2 == samp_freq_table[i].val2)
>> +                     return samp_freq_table[i].odr_bits;
>> +     return -EINVAL;
>> +}
>> +
>> +static int kmx61_set_mode(struct kmx61_data *data, u8 mode, u8 device)
>> +{
>> +     int ret;
>> +
>> +     ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_STBY);
>> +     if (ret < 0) {
>> +             dev_err(&data->client->dev, "Error reading reg_stby\n");
>> +             return ret;
>> +     }
>> +     if (device & KMX61_ACC) {
>> +             if (mode & KMX61_ACC_STBY_BIT)
>> +                     ret |= KMX61_ACC_STBY_BIT;
>> +             else
>> +                     ret &= ~KMX61_ACC_STBY_BIT;
>> +     }
>> +
>> +     if (device & KMX61_MAG) {
>> +             if (mode & KMX61_MAG_STBY_BIT)
>> +                     ret |= KMX61_MAG_STBY_BIT;
>> +             else
>> +                     ret &= ~KMX61_MAG_STBY_BIT;
>> +     }
>> +
>> +     ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_STBY, ret);
>> +     if (ret < 0) {
>> +             dev_err(&data->client->dev, "Error writing reg_stby\n");
>> +             return ret;
>> +     }
>> +
>> +     return ret;
>> +}
>> +
>> +static int kmx61_get_mode(struct kmx61_data *data, u8 *mode, u8 device)
>> +{
>> +     int ret;
>> +
>> +     ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_STBY);
>> +     if (ret < 0) {
>> +             dev_err(&data->client->dev, "Error reading reg_stby\n");
>> +             return ret;
>> +     }
>> +     *mode = 0;
>> +
>> +     if (device & KMX61_ACC) {
>> +             if (ret & KMX61_ACC_STBY_BIT)
>> +                     *mode |= KMX61_ACC_STBY_BIT;
>> +             else
>> +                     *mode &= ~KMX61_ACC_STBY_BIT;
>> +     }
>> +
>> +     if (device & KMX61_MAG) {
>> +             if (ret & KMX61_MAG_STBY_BIT)
>> +                     *mode |= KMX61_MAG_STBY_BIT;
>> +             else
>> +                     *mode &= ~KMX61_MAG_STBY_BIT;
>> +     }
>> +
>> +     return 0;
>> +}
>> +
>> +static int kmx61_set_odr(struct kmx61_data *data, int val, int val2, u8 device)
>> +{
>> +     int ret;
>> +     u8 mode;
>> +     int lodr_bits, odr_bits;
>> +
>> +     ret = kmx61_get_mode(data, &mode, KMX61_ACC | KMX61_MAG);
>> +     if (ret < 0)
>> +             return ret;
>> +
>> +     lodr_bits = kmx61_convert_freq_to_bit(val, val2);
>> +     if (lodr_bits < 0)
>> +             return lodr_bits;
>> +
>> +     /* To change ODR, accel and magn must be in STDBY */
>> +     ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG);
>> +     if (ret < 0)
>> +             return ret;
>> +
>> +     odr_bits = 0;
>> +     if (device & KMX61_ACC)
>> +             odr_bits |= lodr_bits;
>> +     if (device & KMX61_MAG)
>> +             odr_bits |= (lodr_bits << KMX61_MAG_ODR_SHIFT);
>> +
>> +     ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_ODCNTL,
>> +                                     odr_bits);
>> +     if (ret < 0)
>> +             return ret;
>> +
>> +     ret = kmx61_set_mode(data, mode, KMX61_ACC | KMX61_MAG);
>> +     if (ret < 0)
>> +             return ret;
>> +
>> +     data->odr_bits = lodr_bits;
>> +
>> +     return 0;
>> +}
>> +
>> +static
>> +int kmx61_get_odr(struct kmx61_data *data, int *val, int *val2, u8 device)
>> +{    int i;
>> +     u8 lodr_bits;
>> +
>> +     if (device & KMX61_ACC)
>> +             lodr_bits = (data->odr_bits >> KMX61_ACC_ODR_SHIFT) &
>> +                          KMX61_ACC_ODR_MASK;
>> +     else if (device & KMX61_MAG)
>> +             lodr_bits = (data->odr_bits >> KMX61_MAG_ODR_SHIFT) &
>> +                          KMX61_MAG_ODR_MASK;
>> +     else
>> +             return -EINVAL;
>> +
>> +     for (i = 0; i < ARRAY_SIZE(samp_freq_table); i++)
>> +             if (lodr_bits == samp_freq_table[i].odr_bits) {
>> +                     *val = samp_freq_table[i].val;
>> +                     *val2 = samp_freq_table[i].val2;
>> +                     return 0;
>> +             }
>> +     return -EINVAL;
>> +}
>> +
>> +static int kmx61_set_range(struct kmx61_data *data, int range)
>> +{
>> +     int ret;
>> +
>> +     ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_CTRL1);
>> +     if (ret < 0) {
>> +             dev_err(&data->client->dev, "Error reading reg_ctrl1\n");
>> +             return ret;
>> +     }
>> +
>> +     ret &= ~(KMX61_REG_CTRL1_GSEL0_MASK | KMX61_REG_CTRL1_GSEL1_MASK);
>> +     ret |= kmx61_scale_table[range].gsel0 << KMX61_REG_CTRL1_GSEL0_SHIFT;
>> +     ret |= kmx61_scale_table[range].gsel1 << KMX61_REG_CTRL1_GSEL1_SHIFT;
>> +
>> +     ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_CTRL1, ret);
>> +     if (ret < 0) {
>> +             dev_err(&data->client->dev, "Error writing reg_ctrl1\n");
>> +             return ret;
>> +     }
>> +
>> +     data->range = range;
>> +
>> +     return 0;
>> +}
>> +
>> +static int kmx61_set_scale(struct kmx61_data *data, int val)
>> +{
>> +     int ret, i;
>> +     u8  mode;
>> +
>> +     for (i = 0; i < ARRAY_SIZE(kmx61_scale_table); i++) {
>> +             if (kmx61_scale_table[i].scale == val) {
>> +                     ret = kmx61_get_mode(data, &mode,
>> +                                          KMX61_ACC | KMX61_MAG);
>> +                     if (ret < 0)
>> +                             return ret;
>> +
>> +                     ret = kmx61_set_mode(data, KMX61_ALL_STBY,
>> +                                          KMX61_ACC | KMX61_MAG);
>> +                     if (ret < 0)
>> +                             return ret;
>> +
>> +                     ret = kmx61_set_range(data, i);
>> +                     if (ret < 0)
>> +                             return ret;
>> +
>> +                     ret = kmx61_set_mode(data, mode,
>> +                                          KMX61_ACC | KMX61_MAG);
>
> simply return here

Agree. Will fix.

>
>> +                     if (ret < 0)
>> +                             return ret;
>> +
>> +                     return 0;
>> +             }
>> +     }
>> +     return -EINVAL;
>> +}
>> +
>> +static int kmx61_chip_init(struct kmx61_data *data)
>> +{
>> +     int ret;
>> +
>> +     ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_WHO_AM_I);
>> +     if (ret < 0) {
>> +             dev_err(&data->client->dev, "Error reading who_am_i\n");
>> +             return ret;
>> +     }
>> +
>> +     if (ret != KMX61_CHIP_ID) {
>> +             dev_err(&data->client->dev,
>> +                     "Wrong chip id, got %x expected %x\n",
>> +                      ret, KMX61_CHIP_ID);
>> +             return -EINVAL;
>> +     }
>> +
>> +     /* set accel 12bit, 4g range */
>> +     ret = kmx61_set_range(data, KMX61_RANGE_4G);
>> +     if (ret < 0)
>> +             return ret;
>> +
>> +     /* put accel and magnetometer in operating mode */
>> +     ret = kmx61_set_mode(data, 0, KMX61_ACC | KMX61_MAG);
>> +     if (ret < 0)
>> +             return ret;
>> +
>> +     return 0;
>> +}
>> +
>> +static int kmx61_read_measurement(struct kmx61_data *data, int base, int offset)
>> +{
>> +     int ret;
>> +     u8 reg = base + offset * 2;
>> +
>> +     ret = i2c_smbus_read_word_data(data->client, reg);
>> +     if (ret < 0) {
>> +             dev_err(&data->client->dev, "failed to read reg at %x\n", reg);
>> +             return ret;
>> +     }
>> +
>> +     return ret;
>> +}
>> +
>> +static int kmx61_read_raw(struct iio_dev *indio_dev,
>> +                           struct iio_chan_spec const *chan, int *val,
>> +                           int *val2, long mask)
>> +{
>> +     struct kmx61_data *data = iio_priv(indio_dev);
>> +     int ret;
>> +     u8 base_reg;
>> +     u8 device;
>> +
>> +     switch (mask) {
>> +     case IIO_CHAN_INFO_RAW:
>> +             switch (chan->type) {
>> +             case IIO_ACCEL: case IIO_MAGN:
>
> cases on separate lines would be more readable
Ok.
>
>> +                     base_reg = KMX61_ACC_XOUT_L;
>> +                     break;
>> +             default:
>> +                     return -EINVAL;
>> +             }
>> +             ret = kmx61_read_measurement(data, base_reg, chan->scan_index);
>> +             if (ret < 0)
>> +                     return ret;
>> +             *val = sign_extend32(ret >> chan->scan_type.shift,
>> +                                  chan->scan_type.realbits - 1);
>> +             return IIO_VAL_INT;
>> +     case IIO_CHAN_INFO_SCALE:
>> +             switch (chan->type) {
>> +             case IIO_ACCEL:
>> +                     *val = 0;
>> +                     *val2 = kmx61_scale_table[data->range].scale;
>> +                     return IIO_VAL_INT_PLUS_MICRO;
>> +             case IIO_MAGN:
>> +                     /* 14 bits res, 1465 microGauss per magn count */
>> +                     *val = 0;
>> +                     *val2 = 1465;
>> +                     return IIO_VAL_INT_PLUS_MICRO;
>> +             default:
>
> could just return -EINVAL here
>
>> +                     break;
>> +             }
>> +     case IIO_CHAN_INFO_SAMP_FREQ:
>> +             switch (chan->type) {
>> +             case IIO_ACCEL:
>> +                     device = KMX61_ACC;
>> +                     break;
>> +             case IIO_MAGN:
>> +                     device = KMX61_MAG;
>> +                     break;
>> +             default:
>> +                     return -EINVAL;
>> +             }
>> +
>> +             mutex_lock(&data->lock);
>> +             ret = kmx61_get_odr(data, val, val2, device);
>> +             mutex_unlock(&data->lock);
>> +             if (ret)
>> +                     return -EINVAL;
>> +             return IIO_VAL_INT_PLUS_MICRO;
>> +     }
>> +     return -EINVAL;
>> +}
>> +
>> +static int kmx61_write_raw(struct iio_dev *indio_dev,
>> +                            struct iio_chan_spec const *chan, int val,
>> +                            int val2, long mask)
>> +{
>> +     struct kmx61_data *data = iio_priv(indio_dev);
>> +     int ret;
>> +     u8 device;
>> +
>> +     switch (mask) {
>> +     case IIO_CHAN_INFO_SAMP_FREQ:
>
> you could use chan->address to store the device type (ACC or MAG) and save
> the switch block (here and in other places)
>
>> +             switch (chan->type) {
>> +             case IIO_ACCEL:
>> +                     device = KMX61_ACC;
>> +                     break;
>> +             case IIO_MAGN:
>> +                     device = KMX61_MAG;
>> +                     break;
>> +             default:
>> +                     return -EINVAL;
>> +             }
>> +             mutex_lock(&data->lock);
>> +             ret = kmx61_set_odr(data, val, val2, device);
>> +             mutex_unlock(&data->lock);
>
> follow edits are a matter of taste :)
>
> return ret;
>
>> +             break;
>> +     case IIO_CHAN_INFO_SCALE:
>> +             switch (chan->type) {
>> +             case IIO_ACCEL:
>> +                     mutex_lock(&data->lock);
>> +                     ret = kmx61_set_scale(data, val2);
>> +                     mutex_unlock(&data->lock);
>> +                     break;
>> +             default:
>> +                     ret  = -EINVAL;
>
> return -EINVAL
>
>> +             }
>
> return ret;
>
>> +             break;
>> +     default:
>
> return -EINVAL;
>
>
>> +             ret = -EINVAL;
>> +     }
>> +
>> +     return ret;
>> +}
>> +
>> +static const struct iio_info kmx61_info = {
>> +     .driver_module          = THIS_MODULE,
>> +     .read_raw               = kmx61_read_raw,
>> +     .write_raw              = kmx61_write_raw,
>> +     .attrs                  = &kmx61_attribute_group,
>> +};
>> +
>> +static int kmx61_probe(struct i2c_client *client,
>> +                    const struct i2c_device_id *id)
>> +{
>> +     struct kmx61_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;
>> +
>> +     indio_dev->dev.parent = &client->dev;
>> +     indio_dev->info = &kmx61_info;
>
> set indio_dev->name?

Will fix. What is this used for anyway?  :)

>
>> +     indio_dev->channels = kmx61_channels;
>> +     indio_dev->num_channels = ARRAY_SIZE(kmx61_channels);
>> +     indio_dev->modes = INDIO_DIRECT_MODE;
>> +
>> +     mutex_init(&data->lock);
>> +
>> +     ret = kmx61_chip_init(data);
>> +     if (ret < 0)
>> +             return ret;
>> +
>> +     return iio_device_register(indio_dev);
>> +}
>> +
>> +static int kmx61_remove(struct i2c_client *client)
>> +{
>> +     struct iio_dev *indio_dev = i2c_get_clientdata(client);
>> +     struct kmx61_data *data = iio_priv(indio_dev);
>> +     int ret;
>> +
>> +     iio_device_unregister(indio_dev);
>> +
>> +     mutex_lock(&data->lock);
>> +     ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG);
>> +     mutex_unlock(&data->lock);
>> +
>> +     return ret;
>> +}
>> +
>> +static const struct i2c_device_id kmx61_id[] = {
>> +     {"kmx61", 0},
>> +     {}
>> +};
>> +
>> +MODULE_DEVICE_TABLE(i2c, kmx61_id);
>> +
>> +static struct i2c_driver kmx61_driver = {
>> +     .driver = {
>> +             .name = "kmx61",
>> +     },
>> +     .probe          = kmx61_probe,
>> +     .remove         = kmx61_remove,
>> +     .id_table       = kmx61_id,
>> +};
>> +
>> +module_i2c_driver(kmx61_driver);
>> +
>> +MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
>> +MODULE_DESCRIPTION("KMX61 accelerometer/magnetometer driver");
>> +MODULE_LICENSE("GPL v2");
>>

Thanks a lot Peter!

Daniel.

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v2] iio: imu: Add support for Kionix KMX61 sensor
  2014-11-17 12:12   ` Daniel Baluta
@ 2014-11-22 10:41     ` Jonathan Cameron
  0 siblings, 0 replies; 6+ messages in thread
From: Jonathan Cameron @ 2014-11-22 10:41 UTC (permalink / raw)
  To: Daniel Baluta; +Cc: linux-iio, Srinivas Pandruvada, Linux Kernel Mailing List

On 17/11/14 12:12, Daniel Baluta wrote:
> On Sun, Nov 16, 2014 at 11:10 PM, Jonathan Cameron <jic23@kernel.org> wrote:
>> On 10/11/14 17:24, Daniel Baluta wrote:
>>> Minimal implementation for KMX61 6-axis accelerometer/magnetometer. It exports
>>> raw accel/magn readings together with scale and sampling frequency.
>>>
>>> Datasheet will be available at:
>>> http://www.kionix.com/6-axis-accelerometer-magnetometer/kmx61
>>>
>>> Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
>> Looking very nice.    I made a few more comments inline but only
>> one was more than a comment - I added a check on val==0 in the obvious
>> place.  Please take a look at the testing branch of iio.git to make
>> sure I didn't mess anything up!
> 
> Thanks! It looks good.
Dropped this version as discussed. Will take a look at V3 in a few mins.
> 
>>
>> Applied to the togreg branch of iio.git - initially pushed out as testing
>> for the autobuilders to play with it.
>>
>> Jonathan
>>> ---
>>> Changes since v1:
>>>       * serialize non-atomic operations with a mutex (set_odr/get_odr, set_scale).
>>>       * no need to protect reading info scale because it reduces to reading an u8
>>>       which should be atomic on all arches
>>>       * *note* - read_measurment is an atomic operation
>>>
>>>  drivers/iio/imu/Kconfig  |   9 +
>>>  drivers/iio/imu/Makefile |   2 +
>>>  drivers/iio/imu/kmx61.c  | 590 +++++++++++++++++++++++++++++++++++++++++++++++
>>>  3 files changed, 601 insertions(+)
>>>  create mode 100644 drivers/iio/imu/kmx61.c
>>>
>>> diff --git a/drivers/iio/imu/Kconfig b/drivers/iio/imu/Kconfig
>>> index 2b0e451..d675f43 100644
>>> --- a/drivers/iio/imu/Kconfig
>>> +++ b/drivers/iio/imu/Kconfig
>>> @@ -25,6 +25,15 @@ config ADIS16480
>>>         Say yes here to build support for Analog Devices ADIS16375, ADIS16480,
>>>         ADIS16485, ADIS16488 inertial sensors.
>>>
>>> +config KMX61
>>> +     tristate "Kionix KMX61 6-axis accelerometer and magnetometer"
>>> +     depends on I2C
>>> +     help
>>> +       Say Y here if you want to build a driver for Kionix KMX61 6-axis accelerometer
>>> +       and magnetometer.
>>> +       To compile this driver as module, choose M here: the module will be called
>>> +       kmx61.
>>> +
>>>  source "drivers/iio/imu/inv_mpu6050/Kconfig"
>>>
>>>  endmenu
>>> diff --git a/drivers/iio/imu/Makefile b/drivers/iio/imu/Makefile
>>> index 114d2c1..e1e6e3d 100644
>>> --- a/drivers/iio/imu/Makefile
>>> +++ b/drivers/iio/imu/Makefile
>>> @@ -14,3 +14,5 @@ adis_lib-$(CONFIG_IIO_ADIS_LIB_BUFFER) += adis_buffer.o
>>>  obj-$(CONFIG_IIO_ADIS_LIB) += adis_lib.o
>>>
>>>  obj-y += inv_mpu6050/
>>> +
>>> +obj-$(CONFIG_KMX61) += kmx61.o
>>> diff --git a/drivers/iio/imu/kmx61.c b/drivers/iio/imu/kmx61.c
>>> new file mode 100644
>>> index 0000000..6135a16
>>> --- /dev/null
>>> +++ b/drivers/iio/imu/kmx61.c
>>> @@ -0,0 +1,590 @@
>>> +/*
>>> + * KMX61 - Kionix 6-axis Accelerometer/Magnetometer
>>> + *
>>> + * Copyright (c) 2014, Intel Corporation.
>>> + *
>>> + * This file is subject to the terms and conditions of version 2 of
>>> + * the GNU General Public License.  See the file COPYING in the main
>>> + * directory of this archive for more details.
>>> + *
>>> + * IIO driver for KMX61 (7-bit I2C slave address 0x0E or 0x0F).
>>> + *
>>> + * TODO: buffer, interrupt, thresholds, acpi, temperature sensor
>>> + *
>>> + */
>>> +
>>> +#include <linux/module.h>
>>> +#include <linux/i2c.h>
>>> +#include <linux/iio/iio.h>
>>> +#include <linux/iio/sysfs.h>
>>> +
>>> +#define KMX61_DRV_NAME "kmx61"
>>> +
>>> +#define KMX61_REG_WHO_AM_I           0x00
>>> +
>>> +#define KMX61_ACC_XOUT_L             0x0A
>>> +
>>> +#define KMX61_ACC_XOUT_H             0x0B
>>> +#define KMX61_ACC_YOUT_L             0x0C
>>> +#define KMX61_ACC_YOUT_H             0x0D
>>> +#define KMX61_ACC_ZOUT_L             0x0E
>>> +#define KMX61_ACC_ZOUT_H             0x0F
>>> +
>>> +#define KMX61_MAG_XOUT_L             0x12
>>> +
>>> +#define KMX61_MAG_XOUT_H             0x13
>>> +#define KMX61_MAG_YOUT_L             0x14
>>> +#define KMX61_MAG_YOUT_H             0x15
>>> +#define KMX61_MAG_ZOUT_L             0x16
>>> +#define KMX61_MAG_ZOUT_H             0x17
>>> +
>>> +#define KMX61_REG_ODCNTL             0x2C
>>> +
>>> +#define KMX61_REG_STBY                       0x29
>>> +#define KMX61_REG_CTRL1                      0x2A
>>> +
>>> +#define KMX61_REG_COTR                       0x3C
>>> +
>>> +#define KMX61_ACC_STBY_BIT   BIT(0)
>>> +#define KMX61_MAG_STBY_BIT   BIT(1)
>>> +#define KMX61_ACT_STBY_BIT   BIT(7)
>>> +
>>> +#define KMX61_ALL_STBY               (KMX61_ACC_STBY_BIT | KMX61_MAG_STBY_BIT)
>>> +
>>> +#define KMX61_REG_CTRL1_GSEL0_SHIFT  0
>>> +#define KMX61_REG_CTRL1_GSEL1_SHIFT  1
>>> +#define KMX61_REG_CTRL1_GSEL0_MASK   0x01
>>> +#define KMX61_REG_CTRL1_GSEL1_MASK   0x02
>>> +
>>> +#define KMX61_REG_CTRL1_BIT_RES              BIT(4)
>>> +
>>> +#define KMX61_ACC_ODR_SHIFT  0
>>> +#define KMX61_MAG_ODR_SHIFT  4
>>> +#define KMX61_ACC_ODR_MASK   0x0F
>>> +#define KMX61_MAG_ODR_MASK   0xF0
>>> +
>>> +#define KMX61_CHIP_ID                0x12
>>> +
>>> +struct kmx61_data {
>>> +     struct i2c_client *client;
>>> +     /* serialize access to non-atomic ops, e.g set_mode */
>>> +     struct mutex lock;
>>> +     u8 range;
>>> +     u8 odr_bits;
>>> +};
>>> +
>>> +enum kmx61_range {
>>> +     KMX61_RANGE_2G,
>>> +     KMX61_RANGE_4G,
>>> +     KMX61_RANGE_8G,
>>> +};
>>> +
>>> +enum kmx61_scan {
>>> +     KMX61_SCAN_ACC_X,
>>> +     KMX61_SCAN_ACC_Y,
>>> +     KMX61_SCAN_ACC_Z,
>>> +     KMX61_SCAN_TEMP,
>>> +     KMX61_SCAN_MAG_X,
>>> +     KMX61_SCAN_MAG_Y,
>>> +     KMX61_SCAN_MAG_Z,
>>> +};
>>> +
>>> +static const struct {
>>> +     u16 scale;
>>> +     u8 gsel0;
>>> +     u8 gsel1;
>>> +} kmx61_scale_table[] = {
>>> +     {9582, 0, 0},
>>> +     {19163, 1, 0},
>>> +     {38326, 0, 1},
>>> +};
>>> +
>>> +/* KMX61 devices */
>>> +#define KMX61_ACC    0x01
>>> +#define KMX61_MAG    0x02
>>> +
>>> +static const struct {
>>> +     int val;
>>> +     int val2;
>>> +     int odr_bits;
>>> +} samp_freq_table[] = { {12, 500000, 0x00},
>>> +                     {25, 0, 0x01},
>>> +                     {50, 0, 0x02},
>>> +                     {100, 0, 0x03},
>>> +                     {200, 0, 0x04},
>>> +                     {400, 0, 0x05},
>>> +                     {800, 0, 0x06},
>>> +                     {1600, 0, 0x07},
>>> +                     {0, 781000, 0x08},
>>> +                     {1, 563000, 0x09},
>>> +                     {3, 125000, 0x0A},
>>> +                     {6, 250000, 0x0B} };
>>> +
>>> +static IIO_CONST_ATTR(accel_scale_available, "0.009582 0.019163 0.038326");
>>> +static IIO_CONST_ATTR(magn_scale_available, "0.001465");
>>> +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
>>> +     "0.781000 1.563000 3.125000 6.250000 12.500000 25 50 100 200 400 800");
>>> +
>>> +static struct attribute *kmx61_attributes[] = {
>>> +     &iio_const_attr_accel_scale_available.dev_attr.attr,
>>> +     &iio_const_attr_magn_scale_available.dev_attr.attr,
>>> +     &iio_const_attr_sampling_frequency_available.dev_attr.attr,
>> Interesting.  So sampling frequency is controllable seperately for the
>> two sensing types, but uses a single set of values.  This is a rare
>> coherent looking bit of dual sensor type hardware ;)
> 
> Yes.
> 
> Anyway, when the FIFO hardware buffer is used, it  will be updated
> at the faster of the two output data rates
> 
>>> +     NULL,
>>> +};
>>> +
>>> +static const struct attribute_group kmx61_attribute_group = {
>>> +     .attrs = kmx61_attributes,
>>> +};
>>> +
>>> +#define KMX61_ACC_CHAN(_axis, _index) { \
>>> +     .type = IIO_ACCEL, \
>>> +     .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 = _index, \
>>> +     .scan_type = { \
>>> +             .sign = 's', \
>>> +             .realbits = 12, \
>>> +             .storagebits = 16, \
>>> +             .shift = 4, \
>>> +             .endianness = IIO_BE, \
>>> +     }, \
>>> +}
>>> +
>>> +#define KMX61_MAG_CHAN(_axis, _index) { \
>>> +     .type = IIO_MAGN, \
>>> +     .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 = _index, \
>>> +     .scan_type = { \
>>> +             .sign = 's', \
>>> +             .realbits = 14, \
>>> +             .storagebits = 16, \
>>> +             .shift = 2, \
>>> +             .endianness = IIO_BE, \
>>> +     }, \
>> Wouldn't normally expect scan_index and scan_type in a driver
>> without buffered support, but you do make use of some of the
>> elements elsewhere and state that buffered support
>> is on the todo list so lets leave it here.
>>> +}
>>> +
>>> +static const struct iio_chan_spec kmx61_channels[] = {
>>> +     KMX61_ACC_CHAN(X, KMX61_SCAN_ACC_X),
>>> +     KMX61_ACC_CHAN(Y, KMX61_SCAN_ACC_Y),
>>> +     KMX61_ACC_CHAN(Z, KMX61_SCAN_ACC_Z),
>>> +     KMX61_MAG_CHAN(X, KMX61_SCAN_MAG_X),
>>> +     KMX61_MAG_CHAN(Y, KMX61_SCAN_MAG_Y),
>>> +     KMX61_MAG_CHAN(Z, KMX61_SCAN_MAG_Z),
>>> +};
>>> +
>>> +static int kmx61_convert_freq_to_bit(int val, int val2)
>>> +{
>>> +     int i;
>>> +
>>> +     for (i = 0; i < ARRAY_SIZE(samp_freq_table); i++)
>>> +             if (val == samp_freq_table[i].val &&
>>> +                 val2 == samp_freq_table[i].val2)
>>> +                     return samp_freq_table[i].odr_bits;
>>> +     return -EINVAL;
>>> +}
>>> +
>>> +static int kmx61_set_mode(struct kmx61_data *data, u8 mode, u8 device)
>>> +{
>>> +     int ret;
>>> +
>>> +     ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_STBY);
>>> +     if (ret < 0) {
>>> +             dev_err(&data->client->dev, "Error reading reg_stby\n");
>>> +             return ret;
>>> +     }
>>> +     if (device & KMX61_ACC) {
>>> +             if (mode & KMX61_ACC_STBY_BIT)
>>> +                     ret |= KMX61_ACC_STBY_BIT;
>>> +             else
>>> +                     ret &= ~KMX61_ACC_STBY_BIT;
>>> +     }
>>> +
>>> +     if (device & KMX61_MAG) {
>>> +             if (mode & KMX61_MAG_STBY_BIT)
>>> +                     ret |= KMX61_MAG_STBY_BIT;
>>> +             else
>>> +                     ret &= ~KMX61_MAG_STBY_BIT;
>>> +     }
>>> +
>>> +     ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_STBY, ret);
>>> +     if (ret < 0) {
>>> +             dev_err(&data->client->dev, "Error writing reg_stby\n");
>>> +             return ret;
>>> +     }
>>> +
>>> +     return ret;
>>> +}
>>> +
>>> +static int kmx61_get_mode(struct kmx61_data *data, u8 *mode, u8 device)
>>> +{
>>> +     int ret;
>>> +
>>> +     ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_STBY);
>>> +     if (ret < 0) {
>>> +             dev_err(&data->client->dev, "Error reading reg_stby\n");
>>> +             return ret;
>>> +     }
>>> +     *mode = 0;
>>> +
>>> +     if (device & KMX61_ACC) {
>>> +             if (ret & KMX61_ACC_STBY_BIT)
>>> +                     *mode |= KMX61_ACC_STBY_BIT;
>>> +             else
>>> +                     *mode &= ~KMX61_ACC_STBY_BIT;
>>> +     }
>>> +
>>> +     if (device & KMX61_MAG) {
>>> +             if (ret & KMX61_MAG_STBY_BIT)
>>> +                     *mode |= KMX61_MAG_STBY_BIT;
>>> +             else
>>> +                     *mode &= ~KMX61_MAG_STBY_BIT;
>>> +     }
>>> +
>>> +     return 0;
>>> +}
>>> +
>>> +static int kmx61_set_odr(struct kmx61_data *data, int val, int val2, u8 device)
>>> +{
>>> +     int ret;
>>> +     u8 mode;
>>> +     int lodr_bits, odr_bits;
>>> +
>>> +     ret = kmx61_get_mode(data, &mode, KMX61_ACC | KMX61_MAG);
>>> +     if (ret < 0)
>>> +             return ret;
>>> +
>>> +     lodr_bits = kmx61_convert_freq_to_bit(val, val2);
>>> +     if (lodr_bits < 0)
>>> +             return lodr_bits;
>>> +
>>> +     /* To change ODR, accel and magn must be in STDBY */
>>> +     ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG);
>>> +     if (ret < 0)
>>> +             return ret;
>>> +
>>> +     odr_bits = 0;
>>> +     if (device & KMX61_ACC)
>>> +             odr_bits |= lodr_bits;
>>> +     if (device & KMX61_MAG)
>>> +             odr_bits |= (lodr_bits << KMX61_MAG_ODR_SHIFT);
>>> +
>>> +     ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_ODCNTL,
>>> +                                     odr_bits);
>>> +     if (ret < 0)
>>> +             return ret;
>>> +
>>> +     ret = kmx61_set_mode(data, mode, KMX61_ACC | KMX61_MAG);
>>> +     if (ret < 0)
>>> +             return ret;
>>> +
>>> +     data->odr_bits = lodr_bits;
>>> +
>>> +     return 0;
>>> +}
>>> +
>>> +static
>>> +int kmx61_get_odr(struct kmx61_data *data, int *val, int *val2, u8 device)
>>> +{    int i;
>>> +     u8 lodr_bits;
>>> +
>>> +     if (device & KMX61_ACC)
>>> +             lodr_bits = (data->odr_bits >> KMX61_ACC_ODR_SHIFT) &
>>> +                          KMX61_ACC_ODR_MASK;
>>> +     else if (device & KMX61_MAG)
>>> +             lodr_bits = (data->odr_bits >> KMX61_MAG_ODR_SHIFT) &
>>> +                          KMX61_MAG_ODR_MASK;
>>> +     else
>>> +             return -EINVAL;
>>> +
>>> +     for (i = 0; i < ARRAY_SIZE(samp_freq_table); i++)
>>> +             if (lodr_bits == samp_freq_table[i].odr_bits) {
>>> +                     *val = samp_freq_table[i].val;
>>> +                     *val2 = samp_freq_table[i].val2;
>>> +                     return 0;
>>> +             }
>>> +     return -EINVAL;
>>> +}
>>> +
>>> +static int kmx61_set_range(struct kmx61_data *data, int range)
>>> +{
>>> +     int ret;
>>> +
>>> +     ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_CTRL1);
>>> +     if (ret < 0) {
>>> +             dev_err(&data->client->dev, "Error reading reg_ctrl1\n");
>>> +             return ret;
>>> +     }
>>> +
>>> +     ret &= ~(KMX61_REG_CTRL1_GSEL0_MASK | KMX61_REG_CTRL1_GSEL1_MASK);
>>> +     ret |= kmx61_scale_table[range].gsel0 << KMX61_REG_CTRL1_GSEL0_SHIFT;
>>> +     ret |= kmx61_scale_table[range].gsel1 << KMX61_REG_CTRL1_GSEL1_SHIFT;
>>> +
>>> +     ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_CTRL1, ret);
>>> +     if (ret < 0) {
>>> +             dev_err(&data->client->dev, "Error writing reg_ctrl1\n");
>>> +             return ret;
>>> +     }
>>> +
>>> +     data->range = range;
>>> +
>>> +     return 0;
>>> +}
>>> +
>> I'd be tempted to use a parameter name other than val as that
>> tends to have a fairly specific meaning in iio drivers
>> (afterall you pass val2 in here!)  scale would work or
>> maybe microscale or similar?
> 
> 'scale' works for me. I will send a cleanup patch.
> 
>>> +static int kmx61_set_scale(struct kmx61_data *data, int val)
>>> +{
>>> +     int ret, i;
>>> +     u8  mode;
>>> +
>>> +     for (i = 0; i < ARRAY_SIZE(kmx61_scale_table); i++) {
>>> +             if (kmx61_scale_table[i].scale == val) {
>>> +                     ret = kmx61_get_mode(data, &mode,
>>> +                                          KMX61_ACC | KMX61_MAG);
>>> +                     if (ret < 0)
>>> +                             return ret;
>>> +
>>> +                     ret = kmx61_set_mode(data, KMX61_ALL_STBY,
>>> +                                          KMX61_ACC | KMX61_MAG);
>>> +                     if (ret < 0)
>>> +                             return ret;
>>> +
>>> +                     ret = kmx61_set_range(data, i);
>>> +                     if (ret < 0)
>>> +                             return ret;
>>> +
>>> +                     ret = kmx61_set_mode(data, mode,
>>> +                                          KMX61_ACC | KMX61_MAG);
>>> +                     if (ret < 0)
>>> +                             return ret;
>>> +
>>> +                     return 0;
>>> +             }
>>> +     }
>>> +     return -EINVAL;
>>> +}
>>> +
>>> +static int kmx61_chip_init(struct kmx61_data *data)
>>> +{
>>> +     int ret;
>>> +
>>> +     ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_WHO_AM_I);
>>> +     if (ret < 0) {
>>> +             dev_err(&data->client->dev, "Error reading who_am_i\n");
>>> +             return ret;
>>> +     }
>>> +
>>> +     if (ret != KMX61_CHIP_ID) {
>>> +             dev_err(&data->client->dev,
>>> +                     "Wrong chip id, got %x expected %x\n",
>>> +                      ret, KMX61_CHIP_ID);
>>> +             return -EINVAL;
>>> +     }
>>> +
>>> +     /* set accel 12bit, 4g range */
>>> +     ret = kmx61_set_range(data, KMX61_RANGE_4G);
>>> +     if (ret < 0)
>>> +             return ret;
>>> +
>>> +     /* put accel and magnetometer in operating mode */
>>> +     ret = kmx61_set_mode(data, 0, KMX61_ACC | KMX61_MAG);
>>> +     if (ret < 0)
>>> +             return ret;
>>> +
>>> +     return 0;
>>> +}
>>> +
>>> +static int kmx61_read_measurement(struct kmx61_data *data, int base, int offset)
>>> +{
>>> +     int ret;
>>> +     u8 reg = base + offset * 2;
>>> +
>>> +     ret = i2c_smbus_read_word_data(data->client, reg);
>>> +     if (ret < 0) {
>>> +             dev_err(&data->client->dev, "failed to read reg at %x\n", reg);
>>> +             return ret;
>>> +     }
>>> +
>>> +     return ret;
>>> +}
>>> +
>>> +static int kmx61_read_raw(struct iio_dev *indio_dev,
>>> +                           struct iio_chan_spec const *chan, int *val,
>>> +                           int *val2, long mask)
>>> +{
>>> +     struct kmx61_data *data = iio_priv(indio_dev);
>>> +     int ret;
>>> +     u8 base_reg;
>>> +     u8 device;
>>> +
>>> +     switch (mask) {
>>> +     case IIO_CHAN_INFO_RAW:
>>> +             switch (chan->type) {
>>> +             case IIO_ACCEL: case IIO_MAGN:
>>> +                     base_reg = KMX61_ACC_XOUT_L;
>>> +                     break;
>>> +             default:
>>> +                     return -EINVAL;
>>> +             }
>>> +             ret = kmx61_read_measurement(data, base_reg, chan->scan_index);
>>> +             if (ret < 0)
>>> +                     return ret;
>>> +             *val = sign_extend32(ret >> chan->scan_type.shift,
>>> +                                  chan->scan_type.realbits - 1);
>>> +             return IIO_VAL_INT;
>>> +     case IIO_CHAN_INFO_SCALE:
>>> +             switch (chan->type) {
>>> +             case IIO_ACCEL:
>>> +                     *val = 0;
>>> +                     *val2 = kmx61_scale_table[data->range].scale;
>>> +                     return IIO_VAL_INT_PLUS_MICRO;
>>> +             case IIO_MAGN:
>>> +                     /* 14 bits res, 1465 microGauss per magn count */
>>> +                     *val = 0;
>>> +                     *val2 = 1465;
>>> +                     return IIO_VAL_INT_PLUS_MICRO;
>>> +             default:
>>> +                     break;
>>> +             }
>>> +     case IIO_CHAN_INFO_SAMP_FREQ:
>>> +             switch (chan->type) {
>>> +             case IIO_ACCEL:
>>> +                     device = KMX61_ACC;
>>> +                     break;
>>> +             case IIO_MAGN:
>>> +                     device = KMX61_MAG;
>>> +                     break;
>>> +             default:
>>> +                     return -EINVAL;
>>> +             }
>>> +
>>> +             mutex_lock(&data->lock);
>>> +             ret = kmx61_get_odr(data, val, val2, device);
>>> +             mutex_unlock(&data->lock);
>>> +             if (ret)
>>> +                     return -EINVAL;
>>> +             return IIO_VAL_INT_PLUS_MICRO;
>>> +     }
>>> +     return -EINVAL;
>>> +}
>>> +
>>> +static int kmx61_write_raw(struct iio_dev *indio_dev,
>>> +                            struct iio_chan_spec const *chan, int val,
>>> +                            int val2, long mask)
>>> +{
>>> +     struct kmx61_data *data = iio_priv(indio_dev);
>>> +     int ret;
>>> +     u8 device;
>>> +
>>> +     switch (mask) {
>>> +     case IIO_CHAN_INFO_SAMP_FREQ:
>>> +             switch (chan->type) {
>>> +             case IIO_ACCEL:
>>> +                     device = KMX61_ACC;
>>> +                     break;
>>> +             case IIO_MAGN:
>>> +                     device = KMX61_MAG;
>>> +                     break;
>>> +             default:
>>> +                     return -EINVAL;
>>> +             }
>>> +             mutex_lock(&data->lock);
>>> +             ret = kmx61_set_odr(data, val, val2, device);
>>> +             mutex_unlock(&data->lock);
>>> +             break;
>>> +     case IIO_CHAN_INFO_SCALE:
>>> +             switch (chan->type) {
>>> +             case IIO_ACCEL:
>>
>> Should verify that val == 0 incase of crazy userspace input.
> 
> Looks good. Thanks for updating the patch.
> 
>>> +                     mutex_lock(&data->lock);
>>> +                     ret = kmx61_set_scale(data, val2);
>>> +                     mutex_unlock(&data->lock);
>>> +                     break;
>>> +             default:
>>> +                     ret  = -EINVAL;
>>> +             }
>>> +             break;
>>> +     default:
>>> +             ret = -EINVAL;
>>> +     }
>>> +
>>> +     return ret;
>>> +}
>>> +
>>> +static const struct iio_info kmx61_info = {
>>> +     .driver_module          = THIS_MODULE,
>>> +     .read_raw               = kmx61_read_raw,
>>> +     .write_raw              = kmx61_write_raw,
>>> +     .attrs                  = &kmx61_attribute_group,
>>> +};
>>> +
>>> +static int kmx61_probe(struct i2c_client *client,
>>> +                    const struct i2c_device_id *id)
>>> +{
>>> +     struct kmx61_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;
>>> +
>>> +     indio_dev->dev.parent = &client->dev;
>>> +     indio_dev->info = &kmx61_info;
>>> +     indio_dev->channels = kmx61_channels;
>>> +     indio_dev->num_channels = ARRAY_SIZE(kmx61_channels);
>>> +     indio_dev->modes = INDIO_DIRECT_MODE;
>>> +
>>> +     mutex_init(&data->lock);
>>> +
>>> +     ret = kmx61_chip_init(data);
>>> +     if (ret < 0)
>>> +             return ret;
>>> +
>>> +     return iio_device_register(indio_dev);
>>> +}
>>> +
>>> +static int kmx61_remove(struct i2c_client *client)
>>> +{
>>> +     struct iio_dev *indio_dev = i2c_get_clientdata(client);
>>> +     struct kmx61_data *data = iio_priv(indio_dev);
>>> +     int ret;
>>> +
>>> +     iio_device_unregister(indio_dev);
>>> +
>>> +     mutex_lock(&data->lock);
>>> +     ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG);
>>> +     mutex_unlock(&data->lock);
>>> +
>>> +     return ret;
>>> +}
>>> +
>>> +static const struct i2c_device_id kmx61_id[] = {
>>> +     {"kmx61", 0},
>>> +     {}
>>> +};
>>> +
>>> +MODULE_DEVICE_TABLE(i2c, kmx61_id);
>>> +
>>> +static struct i2c_driver kmx61_driver = {
>>> +     .driver = {
>>> +             .name = "kmx61",
>>> +     },
>>> +     .probe          = kmx61_probe,
>>> +     .remove         = kmx61_remove,
>>> +     .id_table       = kmx61_id,
>>> +};
>>> +
>>> +module_i2c_driver(kmx61_driver);
>>> +
>>> +MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
>>> +MODULE_DESCRIPTION("KMX61 accelerometer/magnetometer driver");
>>> +MODULE_LICENSE("GPL v2");
>>>
>>
>> --
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> --
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> 


^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2014-11-22 10:41 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2014-11-10 17:24 [PATCH v2] iio: imu: Add support for Kionix KMX61 sensor Daniel Baluta
2014-11-16 21:10 ` Jonathan Cameron
2014-11-17 12:12   ` Daniel Baluta
2014-11-22 10:41     ` Jonathan Cameron
2014-11-17 13:46 ` Peter Meerwald
2014-11-17 15:24   ` Daniel Baluta

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