[PATCH v7 0/4] iio: Add support for rotation from north

[PATCH v7 0/4] iio: Add support for rotation from north

[Reyad Attiyat]

This series of patches modifies magn-3d driver to handle the rotation
from north usage. This is done by scanning the report and then building
the iio arrays (vals and channels) dynamically.

Changes from V6
Remove sizeof from function hid_sensor_push_data as it is not used or 
passed to iio_push_to_buffer

Reyad Attiyat (4):
  iio: Documentation: Add documentation for rotation from north sensor
    usage attributes
  iio: types: Added support for rotation from north usage attributes
  iio: hid-sensor-magn-3d: Scan for usage attributes before setting up
    iio channels
  iio: hid-sensor-magn-3d: Add support for rotation from north

 Documentation/ABI/testing/sysfs-bus-iio       |  82 +++++++++++
 drivers/iio/industrialio-core.c               |   4 +
 drivers/iio/magnetometer/hid-sensor-magn-3d.c | 199 ++++++++++++++++++++------
 include/linux/iio/types.h                     |   4 +
 4 files changed, 245 insertions(+), 44 deletions(-)

-- 
1.9.3

[PATCH v7 1/4] iio: Documentation: Add documentation for rotation from north sensor usage attributes

[Reyad Attiyat]

Added documentation for the sysfs attributes supported by the rotation from north
sensor.

Signed-off-by: Reyad Attiyat <reyad.attiyat@gmail.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 Documentation/ABI/testing/sysfs-bus-iio | 82 +++++++++++++++++++++++++++++++++
 1 file changed, 82 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio
index a9757dc..995642f 100644
--- a/Documentation/ABI/testing/sysfs-bus-iio
+++ b/Documentation/ABI/testing/sysfs-bus-iio
@@ -260,6 +260,10 @@ What:		/sys/bus/iio/devices/iio:deviceX/in_magn_scale
 What:		/sys/bus/iio/devices/iio:deviceX/in_magn_x_scale
 What:		/sys/bus/iio/devices/iio:deviceX/in_magn_y_scale
 What:		/sys/bus/iio/devices/iio:deviceX/in_magn_z_scale
+What:		/sys/bus/iio/devices/iio:deviceX/in_rot_from_north_magnetic_scale
+What:		/sys/bus/iio/devices/iio:deviceX/in_rot_from_north_true_scale
+What:		/sys/bus/iio/devices/iio:deviceX/in_rot_from_north_magnetic_tilt_comp_scale
+What:		/sys/bus/iio/devices/iio:deviceX/in_rot_from_north_true_tilt_comp_scale
 What:		/sys/bus/iio/devices/iio:deviceX/in_pressureY_scale
 What:		/sys/bus/iio/devices/iio:deviceX/in_pressure_scale
 KernelVersion:	2.6.35
@@ -447,6 +451,14 @@ What:		/sys/.../iio:deviceX/events/in_magn_y_thresh_rising_en
 What:		/sys/.../iio:deviceX/events/in_magn_y_thresh_falling_en
 What:		/sys/.../iio:deviceX/events/in_magn_z_thresh_rising_en
 What:		/sys/.../iio:deviceX/events/in_magn_z_thresh_falling_en
+What:		/sys/.../iio:deviceX/events/in_rot_from_north_magnetic_thresh_rising_en
+What:		/sys/.../iio:deviceX/events/in_rot_from_north_magnetic_thresh_falling_en
+What:		/sys/.../iio:deviceX/events/in_rot_from_north_true_thresh_rising_en
+What:		/sys/.../iio:deviceX/events/in_rot_from_north_true_thresh_falling_en
+What:		/sys/.../iio:deviceX/events/in_rot_from_north_magnetic_tilt_comp_thresh_rising_en
+What:		/sys/.../iio:deviceX/events/in_rot_from_north_magnetic_tilt_comp_thresh_falling_en
+What:		/sys/.../iio:deviceX/events/in_rot_from_north_true_tilt_comp_thresh_rising_en
+What:		/sys/.../iio:deviceX/events/in_rot_from_north_true_tilt_comp_thresh_falling_en
 What:		/sys/.../iio:deviceX/events/in_voltageY_supply_thresh_rising_en
 What:		/sys/.../iio:deviceX/events/in_voltageY_supply_thresh_falling_en
 What:		/sys/.../iio:deviceX/events/in_voltageY_thresh_rising_en
@@ -492,6 +504,14 @@ What:		/sys/.../iio:deviceX/events/in_magn_y_roc_rising_en
 What:		/sys/.../iio:deviceX/events/in_magn_y_roc_falling_en
 What:		/sys/.../iio:deviceX/events/in_magn_z_roc_rising_en
 What:		/sys/.../iio:deviceX/events/in_magn_z_roc_falling_en
+What:		/sys/.../iio:deviceX/events/in_rot_from_north_magnetic_roc_rising_en
+What:		/sys/.../iio:deviceX/events/in_rot_from_north_magnetic_roc_falling_en
+What:		/sys/.../iio:deviceX/events/in_rot_from_north_true_roc_rising_en
+What:		/sys/.../iio:deviceX/events/in_rot_from_north_true_roc_falling_en
+What:		/sys/.../iio:deviceX/events/in_rot_from_north_magnetic_tilt_comp_roc_rising_en
+What:		/sys/.../iio:deviceX/events/in_rot_from_north_magnetic_tilt_comp_roc_falling_en
+What:		/sys/.../iio:deviceX/events/in_rot_from_north_true_tilt_comp_roc_rising_en
+What:		/sys/.../iio:deviceX/events/in_rot_from_north_true_tilt_comp_roc_falling_en
 What:		/sys/.../iio:deviceX/events/in_voltageY_supply_roc_rising_en
 What:		/sys/.../iio:deviceX/events/in_voltageY_supply_roc_falling_en
 What:		/sys/.../iio:deviceX/events/in_voltageY_roc_rising_en
@@ -538,6 +558,14 @@ What:		/sys/.../events/in_magn_y_raw_thresh_rising_value
 What:		/sys/.../events/in_magn_y_raw_thresh_falling_value
 What:		/sys/.../events/in_magn_z_raw_thresh_rising_value
 What:		/sys/.../events/in_magn_z_raw_thresh_falling_value
+What:		/sys/.../events/in_rot_from_north_magnetic_raw_thresh_rising_value
+What:		/sys/.../events/in_rot_from_north_magnetic_raw_thresh_falling_value
+What:		/sys/.../events/in_rot_from_north_true_raw_thresh_rising_value
+What:		/sys/.../events/in_rot_from_north_true_raw_thresh_falling_value
+What:		/sys/.../events/in_rot_from_north_magnetic_tilt_comp_raw_thresh_rising_value
+What:		/sys/.../events/in_rot_from_north_magnetic_tilt_comp_raw_thresh_falling_value
+What:		/sys/.../events/in_rot_from_north_true_tilt_comp_raw_thresh_rising_value
+What:		/sys/.../events/in_rot_from_north_true_tilt_comp_raw_thresh_falling_value
 What:		/sys/.../events/in_voltageY_supply_raw_thresh_rising_value
 What:		/sys/.../events/in_voltageY_supply_raw_thresh_falling_value
 What:		/sys/.../events/in_voltageY_raw_thresh_rising_value
@@ -588,6 +616,18 @@ What:		/sys/.../events/in_magn_y_thresh_either_hysteresis
 What:		/sys/.../events/in_magn_z_thresh_rising_hysteresis
 What:		/sys/.../events/in_magn_z_thresh_falling_hysteresis
 What:		/sys/.../events/in_magn_z_thresh_either_hysteresis
+What:		/sys/.../events/in_rot_from_north_magnetic_thresh_rising_hysteresis
+What:		/sys/.../events/in_rot_from_north_magnetic_thresh_falling_hysteresis
+What:		/sys/.../events/in_rot_from_north_magnetic_thresh_either_hysteresis
+What:		/sys/.../events/in_rot_from_north_true_thresh_rising_hysteresis
+What:		/sys/.../events/in_rot_from_north_true_thresh_falling_hysteresis
+What:		/sys/.../events/in_rot_from_north_true_thresh_either_hysteresis
+What:		/sys/.../events/in_rot_from_north_magnetic_tilt_comp_thresh_rising_hysteresis
+What:		/sys/.../events/in_rot_from_north_magnetic_tilt_comp_thresh_falling_hysteresis
+What:		/sys/.../events/in_rot_from_north_magnetic_tilt_comp_thresh_either_hysteresis
+What:		/sys/.../events/in_rot_from_north_true_tilt_comp_thresh_rising_hysteresis
+What:		/sys/.../events/in_rot_from_north_true_tilt_comp_thresh_falling_hysteresis
+What:		/sys/.../events/in_rot_from_north_true_tilt_comp_thresh_either_hysteresis
 What:		/sys/.../events/in_voltageY_thresh_rising_hysteresis
 What:		/sys/.../events/in_voltageY_thresh_falling_hysteresis
 What:		/sys/.../events/in_voltageY_thresh_either_hysteresis
@@ -635,6 +675,14 @@ What:		/sys/.../events/in_magn_y_raw_roc_rising_value
 What:		/sys/.../events/in_magn_y_raw_roc_falling_value
 What:		/sys/.../events/in_magn_z_raw_roc_rising_value
 What:		/sys/.../events/in_magn_z_raw_roc_falling_value
+What:		/sys/.../events/in_rot_from_north_magnetic_raw_roc_rising_value
+What:		/sys/.../events/in_rot_from_north_magnetic_raw_roc_falling_value
+What:		/sys/.../events/in_rot_from_north_true_raw_roc_rising_value
+What:		/sys/.../events/in_rot_from_north_true_raw_roc_falling_value
+What:		/sys/.../events/in_rot_from_north_magnetic_tilt_comp_raw_roc_rising_value
+What:		/sys/.../events/in_rot_from_north_magnetic_tilt_comp_raw_roc_falling_value
+What:		/sys/.../events/in_rot_from_north_true_tilt_comp_raw_roc_rising_value
+What:		/sys/.../events/in_rot_from_north_true_tilt_comp_raw_roc_falling_value
 What:		/sys/.../events/in_voltageY_supply_raw_roc_rising_value
 What:		/sys/.../events/in_voltageY_supply_raw_roc_falling_value
 What:		/sys/.../events/in_voltageY_raw_roc_rising_value
@@ -690,6 +738,22 @@ What:		/sys/.../events/in_magn_z_thresh_rising_period
 What:		/sys/.../events/in_magn_z_thresh_falling_period
 What:		/sys/.../events/in_magn_z_roc_rising_period
 What:		/sys/.../events/in_magn_z_roc_falling_period
+What:		/sys/.../events/in_rot_from_north_magnetic_thresh_rising_period
+What:		/sys/.../events/in_rot_from_north_magnetic_thresh_falling_period
+What:		/sys/.../events/in_rot_from_north_magnetic_roc_rising_period
+What:		/sys/.../events/in_rot_from_north_magnetic_roc_falling_period
+What:		/sys/.../events/in_rot_from_north_true_thresh_rising_period
+What:		/sys/.../events/in_rot_from_north_true_thresh_falling_period
+What:		/sys/.../events/in_rot_from_north_true_roc_rising_period
+What:		/sys/.../events/in_rot_from_north_true_roc_falling_period
+What:		/sys/.../events/in_rot_from_north_magnetic_tilt_comp_thresh_rising_period
+What:		/sys/.../events/in_rot_from_north_magnetic_tilt_comp_thresh_falling_period
+What:		/sys/.../events/in_rot_from_north_magnetic_tilt_comp_roc_rising_period
+What:		/sys/.../events/in_rot_from_north_magnetic_tilt_comp_roc_falling_period
+What:		/sys/.../events/in_rot_from_north_true_tilt_comp_thresh_rising_period
+What:		/sys/.../events/in_rot_from_north_true_tilt_comp_thresh_falling_period
+What:		/sys/.../events/in_rot_from_north_true_tilt_comp_roc_rising_period
+What:		/sys/.../events/in_rot_from_north_true_tilt_comp_roc_falling_period
 What:		/sys/.../events/in_voltageY_supply_thresh_rising_period
 What:		/sys/.../events/in_voltageY_supply_thresh_falling_period
 What:		/sys/.../events/in_voltageY_supply_roc_rising_period
@@ -787,6 +851,10 @@ What:		/sys/.../iio:deviceX/scan_elements/in_anglvel_z_en
 What:		/sys/.../iio:deviceX/scan_elements/in_magn_x_en
 What:		/sys/.../iio:deviceX/scan_elements/in_magn_y_en
 What:		/sys/.../iio:deviceX/scan_elements/in_magn_z_en
+What:		/sys/.../iio:deviceX/scan_elements/in_rot_from_north_magnetic_en
+What:		/sys/.../iio:deviceX/scan_elements/in_rot_from_north_true_en
+What:		/sys/.../iio:deviceX/scan_elements/in_rot_from_north_magnetic_tilt_comp_en
+What:		/sys/.../iio:deviceX/scan_elements/in_rot_from_north_true_tilt_comp_en
 What:		/sys/.../iio:deviceX/scan_elements/in_timestamp_en
 What:		/sys/.../iio:deviceX/scan_elements/in_voltageY_supply_en
 What:		/sys/.../iio:deviceX/scan_elements/in_voltageY_en
@@ -853,6 +921,10 @@ What:		/sys/.../iio:deviceX/scan_elements/in_anglvel_z_index
 What:		/sys/.../iio:deviceX/scan_elements/in_magn_x_index
 What:		/sys/.../iio:deviceX/scan_elements/in_magn_y_index
 What:		/sys/.../iio:deviceX/scan_elements/in_magn_z_index
+What:		/sys/.../iio:deviceX/scan_elements/in_rot_from_north_magnetic_index
+What:		/sys/.../iio:deviceX/scan_elements/in_rot_from_north_true_index
+What:		/sys/.../iio:deviceX/scan_elements/in_rot_from_north_magnetic_tilt_comp_index
+What:		/sys/.../iio:deviceX/scan_elements/in_rot_from_north_true_tilt_comp_index
 What:		/sys/.../iio:deviceX/scan_elements/in_incli_x_index
 What:		/sys/.../iio:deviceX/scan_elements/in_incli_y_index
 What:		/sys/.../iio:deviceX/scan_elements/in_timestamp_index
@@ -933,3 +1005,13 @@ Description:
 		x y z w. Here x, y, and z component represents the axis about
 		which a rotation will occur and w component represents the
 		amount of rotation.
+
+What:		/sys/bus/iio/devices/iio:deviceX/in_rot_from_north_magnetic_tilt_comp_raw
+What:		/sys/bus/iio/devices/iio:deviceX/in_rot_from_north_true_tilt_comp_raw
+What:		/sys/bus/iio/devices/iio:deviceX/in_rot_from_north_magnetic_raw
+What:		/sys/bus/iio/devices/iio:deviceX/in_rot_from_north_true_raw
+KernelVersion:	3.15
+Contact:	linux-iio@vger.kernel.org
+Description:
+		Raw value of rotation from true/magnetic north measured with
+		or without compensation from tilt sensors.
-- 
1.9.3

[PATCH v7 2/4] iio: types: Added support for rotation from north usage attributes

[Reyad Attiyat]

Added the rotation from north usage attributes to the iio modifier enum and to the iio modifier names array.

Signed-off-by: Reyad Attiyat <reyad.attiyat@gmail.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 drivers/iio/industrialio-core.c | 4 ++++
 include/linux/iio/types.h       | 4 ++++
 2 files changed, 8 insertions(+)

diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index 4b1f375..af3e76d 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -87,6 +87,10 @@ static const char * const iio_modifier_names[] = {
 	[IIO_MOD_QUATERNION] = "quaternion",
 	[IIO_MOD_TEMP_AMBIENT] = "ambient",
 	[IIO_MOD_TEMP_OBJECT] = "object",
+	[IIO_MOD_NORTH_MAGN] = "from_north_magnetic",
+	[IIO_MOD_NORTH_TRUE] = "from_north_true",
+	[IIO_MOD_NORTH_MAGN_TILT_COMP] = "from_north_magnetic_tilt_comp",
+	[IIO_MOD_NORTH_TRUE_TILT_COMP] = "from_north_true_tilt_comp",
 };
 
 /* relies on pairs of these shared then separate */
diff --git a/include/linux/iio/types.h b/include/linux/iio/types.h
index d480631..d09c40d 100644
--- a/include/linux/iio/types.h
+++ b/include/linux/iio/types.h
@@ -56,6 +56,10 @@ enum iio_modifier {
 	IIO_MOD_QUATERNION,
 	IIO_MOD_TEMP_AMBIENT,
 	IIO_MOD_TEMP_OBJECT,
+	IIO_MOD_NORTH_MAGN,
+	IIO_MOD_NORTH_TRUE,
+	IIO_MOD_NORTH_MAGN_TILT_COMP,
+	IIO_MOD_NORTH_TRUE_TILT_COMP
 };
 
 enum iio_event_type {
-- 
1.9.3

[PATCH v7 3/4] iio: hid-sensor-magn-3d: Scan for usage attributes before setting up iio channels

[Reyad Attiyat]

Scan for and count the HID usage attributes supported by the driver.
This allows for the driver to only setup the IIO channels for the
sensor usages present in the HID USB reports.

Changes from v6
- Fix kernel build error for invalid sizeof by removing the parameter
from the hid_sensor_push_data

Signed-off-by: Reyad Attiyat <reyad.attiyat@gmail.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 drivers/iio/magnetometer/hid-sensor-magn-3d.c | 152 ++++++++++++++++++--------
 1 file changed, 105 insertions(+), 47 deletions(-)

diff --git a/drivers/iio/magnetometer/hid-sensor-magn-3d.c b/drivers/iio/magnetometer/hid-sensor-magn-3d.c
index b2b0937..161fbd4 100644
--- a/drivers/iio/magnetometer/hid-sensor-magn-3d.c
+++ b/drivers/iio/magnetometer/hid-sensor-magn-3d.c
@@ -42,7 +42,12 @@ struct magn_3d_state {
 	struct hid_sensor_hub_callbacks callbacks;
 	struct hid_sensor_common common_attributes;
 	struct hid_sensor_hub_attribute_info magn[MAGN_3D_CHANNEL_MAX];
-	u32 magn_val[MAGN_3D_CHANNEL_MAX];
+
+	/* dynamically sized array to hold sensor values */
+	u32 *iio_vals;
+	/* array of pointers to sensor value */
+	u32 *magn_val_addr[MAGN_3D_CHANNEL_MAX];
+
 	int scale_pre_decml;
 	int scale_post_decml;
 	int scale_precision;
@@ -66,7 +71,6 @@ static const struct iio_chan_spec magn_3d_channels[] = {
 		BIT(IIO_CHAN_INFO_SCALE) |
 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
 		BIT(IIO_CHAN_INFO_HYSTERESIS),
-		.scan_index = CHANNEL_SCAN_INDEX_X,
 	}, {
 		.type = IIO_MAGN,
 		.modified = 1,
@@ -76,7 +80,6 @@ static const struct iio_chan_spec magn_3d_channels[] = {
 		BIT(IIO_CHAN_INFO_SCALE) |
 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
 		BIT(IIO_CHAN_INFO_HYSTERESIS),
-		.scan_index = CHANNEL_SCAN_INDEX_Y,
 	}, {
 		.type = IIO_MAGN,
 		.modified = 1,
@@ -86,7 +89,6 @@ static const struct iio_chan_spec magn_3d_channels[] = {
 		BIT(IIO_CHAN_INFO_SCALE) |
 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
 		BIT(IIO_CHAN_INFO_HYSTERESIS),
-		.scan_index = CHANNEL_SCAN_INDEX_Z,
 	}
 };
 
@@ -126,8 +128,8 @@ static int magn_3d_read_raw(struct iio_dev *indio_dev,
 		msleep_interruptible(poll_value * 2);
 
 		report_id =
-			magn_state->magn[chan->scan_index].report_id;
-		address = magn_3d_addresses[chan->scan_index];
+			magn_state->magn[chan->address].report_id;
+		address = magn_3d_addresses[chan->address];
 		if (report_id >= 0)
 			*val = sensor_hub_input_attr_get_raw_value(
 				magn_state->common_attributes.hsdev,
@@ -200,8 +202,7 @@ static const struct iio_info magn_3d_info = {
 };
 
 /* Function to push data to buffer */
-static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
-	int len)
+static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data)
 {
 	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
 	iio_push_to_buffers(indio_dev, data);
@@ -217,9 +218,7 @@ static int magn_3d_proc_event(struct hid_sensor_hub_device *hsdev,
 
 	dev_dbg(&indio_dev->dev, "magn_3d_proc_event\n");
 	if (atomic_read(&magn_state->common_attributes.data_ready))
-		hid_sensor_push_data(indio_dev,
-				magn_state->magn_val,
-				sizeof(magn_state->magn_val));
+		hid_sensor_push_data(indio_dev, magn_state->iio_vals);
 
 	return 0;
 }
@@ -233,52 +232,119 @@ static int magn_3d_capture_sample(struct hid_sensor_hub_device *hsdev,
 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
 	struct magn_3d_state *magn_state = iio_priv(indio_dev);
 	int offset;
-	int ret = -EINVAL;
+	int ret = 0;
+	u32 *iio_val = NULL;
 
 	switch (usage_id) {
 	case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS:
 	case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Y_AXIS:
 	case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Z_AXIS:
-		offset = usage_id - HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS;
-		magn_state->magn_val[CHANNEL_SCAN_INDEX_X + offset] =
-						*(u32 *)raw_data;
-		ret = 0;
+		offset = (usage_id - HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS)
+				+ CHANNEL_SCAN_INDEX_X;
 	break;
 	default:
-		break;
+		return -EINVAL;
 	}
 
+	iio_val = magn_state->magn_val_addr[offset];
+
+	if (iio_val != NULL)
+		*iio_val = *((u32 *)raw_data);
+	else
+		ret = -EINVAL;
+
 	return ret;
 }
 
 /* Parse report which is specific to an usage id*/
 static int magn_3d_parse_report(struct platform_device *pdev,
 				struct hid_sensor_hub_device *hsdev,
-				struct iio_chan_spec *channels,
+				struct iio_chan_spec **channels,
+				int *chan_count,
 				unsigned usage_id,
 				struct magn_3d_state *st)
 {
-	int ret;
 	int i;
+	int attr_count = 0;
+	struct iio_chan_spec *_channels;
+
+	/* Scan for each usage attribute supported */
+	for (i = 0; i < MAGN_3D_CHANNEL_MAX; i++) {
+		int status;
+		u32 address = magn_3d_addresses[i];
+
+		/* Check if usage attribute exists in the sensor hub device */
+		status = sensor_hub_input_get_attribute_info(hsdev,
+			HID_INPUT_REPORT,
+			usage_id,
+			address,
+			&(st->magn[i]));
+		if (!status)
+			attr_count++;
+	}
 
-	for (i = 0; i <= CHANNEL_SCAN_INDEX_Z; ++i) {
-		ret = sensor_hub_input_get_attribute_info(hsdev,
-				HID_INPUT_REPORT,
-				usage_id,
-				HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS + i,
-				&st->magn[CHANNEL_SCAN_INDEX_X + i]);
-		if (ret < 0)
-			break;
-		magn_3d_adjust_channel_bit_mask(channels,
-				CHANNEL_SCAN_INDEX_X + i,
-				st->magn[CHANNEL_SCAN_INDEX_X + i].size);
+	if (attr_count <= 0) {
+		dev_err(&pdev->dev,
+			"failed to find any supported usage attributes in report\n");
+		return  -EINVAL;
 	}
-	dev_dbg(&pdev->dev, "magn_3d %x:%x, %x:%x, %x:%x\n",
+
+	dev_dbg(&pdev->dev, "magn_3d Found %d usage attributes\n",
+			attr_count);
+	dev_dbg(&pdev->dev, "magn_3d X: %x:%x Y: %x:%x Z: %x:%x\n",
 			st->magn[0].index,
 			st->magn[0].report_id,
 			st->magn[1].index, st->magn[1].report_id,
 			st->magn[2].index, st->magn[2].report_id);
 
+	/* Setup IIO channel array */
+	_channels = devm_kcalloc(&pdev->dev, attr_count,
+				sizeof(struct iio_chan_spec),
+				GFP_KERNEL);
+	if (!_channels) {
+		dev_err(&pdev->dev,
+			"failed to allocate space for iio channels\n");
+		return -ENOMEM;
+	}
+
+	st->iio_vals = devm_kcalloc(&pdev->dev, attr_count,
+				sizeof(u32),
+				GFP_KERNEL);
+	if (!st->iio_vals) {
+		dev_err(&pdev->dev,
+			"failed to allocate space for iio values array\n");
+		return -ENOMEM;
+	}
+
+	for (i = 0, *chan_count = 0;
+	i < MAGN_3D_CHANNEL_MAX && *chan_count < attr_count;
+	i++){
+		if (st->magn[i].index >= 0) {
+			/* Setup IIO channel struct */
+			(_channels[*chan_count]) = magn_3d_channels[i];
+			(_channels[*chan_count]).scan_index = *chan_count;
+			(_channels[*chan_count]).address = i;
+
+			/* Set magn_val_addr to iio value address */
+			st->magn_val_addr[i] = &(st->iio_vals[*chan_count]);
+			magn_3d_adjust_channel_bit_mask(_channels,
+							*chan_count,
+							st->magn[i].size);
+			(*chan_count)++;
+		}
+	}
+
+	if (*chan_count <= 0) {
+		dev_err(&pdev->dev,
+			"failed to find any magnetic channels setup\n");
+		return -EINVAL;
+	}
+
+	*channels = _channels;
+
+	dev_dbg(&pdev->dev, "magn_3d Setup %d IIO channels\n",
+			*chan_count);
+
 	st->scale_precision = hid_sensor_format_scale(
 				HID_USAGE_SENSOR_COMPASS_3D,
 				&st->magn[CHANNEL_SCAN_INDEX_X],
@@ -296,7 +362,7 @@ static int magn_3d_parse_report(struct platform_device *pdev,
 			st->common_attributes.sensitivity.report_id);
 	}
 
-	return ret;
+	return 0;
 }
 
 /* Function to initialize the processing for usage id */
@@ -308,6 +374,7 @@ static int hid_magn_3d_probe(struct platform_device *pdev)
 	struct magn_3d_state *magn_state;
 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 	struct iio_chan_spec *channels;
+	int chan_count = 0;
 
 	indio_dev = devm_iio_device_alloc(&pdev->dev,
 					  sizeof(struct magn_3d_state));
@@ -328,22 +395,16 @@ static int hid_magn_3d_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	channels = kmemdup(magn_3d_channels, sizeof(magn_3d_channels),
-			   GFP_KERNEL);
-	if (!channels) {
-		dev_err(&pdev->dev, "failed to duplicate channels\n");
-		return -ENOMEM;
-	}
-
-	ret = magn_3d_parse_report(pdev, hsdev, channels,
+	ret = magn_3d_parse_report(pdev, hsdev,
+				&channels, &chan_count,
 				HID_USAGE_SENSOR_COMPASS_3D, magn_state);
 	if (ret) {
-		dev_err(&pdev->dev, "failed to setup attributes\n");
-		goto error_free_dev_mem;
+		dev_err(&pdev->dev, "failed to parse report\n");
+		return ret;
 	}
 
 	indio_dev->channels = channels;
-	indio_dev->num_channels = ARRAY_SIZE(magn_3d_channels);
+	indio_dev->num_channels = chan_count;
 	indio_dev->dev.parent = &pdev->dev;
 	indio_dev->info = &magn_3d_info;
 	indio_dev->name = name;
@@ -353,7 +414,7 @@ static int hid_magn_3d_probe(struct platform_device *pdev)
 		NULL, NULL);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
-		goto error_free_dev_mem;
+		return ret;
 	}
 	atomic_set(&magn_state->common_attributes.data_ready, 0);
 	ret = hid_sensor_setup_trigger(indio_dev, name,
@@ -387,8 +448,6 @@ error_remove_trigger:
 	hid_sensor_remove_trigger(&magn_state->common_attributes);
 error_unreg_buffer_funcs:
 	iio_triggered_buffer_cleanup(indio_dev);
-error_free_dev_mem:
-	kfree(indio_dev->channels);
 	return ret;
 }
 
@@ -403,7 +462,6 @@ static int hid_magn_3d_remove(struct platform_device *pdev)
 	iio_device_unregister(indio_dev);
 	hid_sensor_remove_trigger(&magn_state->common_attributes);
 	iio_triggered_buffer_cleanup(indio_dev);
-	kfree(indio_dev->channels);
 
 	return 0;
 }
-- 
1.9.3

[PATCH v7 4/4] iio: hid-sensor-magn-3d: Add support for rotation from north

[Reyad Attiyat]

Add the HID usage attribute ID's and IIO channel info for rotation
from north support.

Signed-off-by: Reyad Attiyat <reyad.attiyat@gmail.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 drivers/iio/magnetometer/hid-sensor-magn-3d.c | 53 ++++++++++++++++++++++++++-
 1 file changed, 52 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/magnetometer/hid-sensor-magn-3d.c b/drivers/iio/magnetometer/hid-sensor-magn-3d.c
index 161fbd4..1e717c7 100644
--- a/drivers/iio/magnetometer/hid-sensor-magn-3d.c
+++ b/drivers/iio/magnetometer/hid-sensor-magn-3d.c
@@ -35,6 +35,10 @@ enum magn_3d_channel {
 	CHANNEL_SCAN_INDEX_X,
 	CHANNEL_SCAN_INDEX_Y,
 	CHANNEL_SCAN_INDEX_Z,
+	CHANNEL_SCAN_INDEX_NORTH_MAGN_TILT_COMP,
+	CHANNEL_SCAN_INDEX_NORTH_TRUE_TILT_COMP,
+	CHANNEL_SCAN_INDEX_NORTH_MAGN,
+	CHANNEL_SCAN_INDEX_NORTH_TRUE,
 	MAGN_3D_CHANNEL_MAX,
 };
 
@@ -57,7 +61,11 @@ struct magn_3d_state {
 static const u32 magn_3d_addresses[MAGN_3D_CHANNEL_MAX] = {
 	HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS,
 	HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Y_AXIS,
-	HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Z_AXIS
+	HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Z_AXIS,
+	HID_USAGE_SENSOR_ORIENT_COMP_MAGN_NORTH,
+	HID_USAGE_SENSOR_ORIENT_COMP_TRUE_NORTH,
+	HID_USAGE_SENSOR_ORIENT_MAGN_NORTH,
+	HID_USAGE_SENSOR_ORIENT_TRUE_NORTH,
 };
 
 /* Channel definitions */
@@ -89,6 +97,42 @@ static const struct iio_chan_spec magn_3d_channels[] = {
 		BIT(IIO_CHAN_INFO_SCALE) |
 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
 		BIT(IIO_CHAN_INFO_HYSTERESIS),
+	}, {
+		.type = IIO_ROT,
+		.modified = 1,
+		.channel2 = IIO_MOD_NORTH_MAGN_TILT_COMP,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
+		BIT(IIO_CHAN_INFO_SCALE) |
+		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+		BIT(IIO_CHAN_INFO_HYSTERESIS),
+	}, {
+		.type = IIO_ROT,
+		.modified = 1,
+		.channel2 = IIO_MOD_NORTH_TRUE_TILT_COMP,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
+		BIT(IIO_CHAN_INFO_SCALE) |
+		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+		BIT(IIO_CHAN_INFO_HYSTERESIS),
+	}, {
+		.type = IIO_ROT,
+		.modified = 1,
+		.channel2 = IIO_MOD_NORTH_MAGN,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
+		BIT(IIO_CHAN_INFO_SCALE) |
+		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+		BIT(IIO_CHAN_INFO_HYSTERESIS),
+	}, {
+		.type = IIO_ROT,
+		.modified = 1,
+		.channel2 = IIO_MOD_NORTH_TRUE,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
+		BIT(IIO_CHAN_INFO_SCALE) |
+		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+		BIT(IIO_CHAN_INFO_HYSTERESIS),
 	}
 };
 
@@ -242,6 +286,13 @@ static int magn_3d_capture_sample(struct hid_sensor_hub_device *hsdev,
 		offset = (usage_id - HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS)
 				+ CHANNEL_SCAN_INDEX_X;
 	break;
+	case HID_USAGE_SENSOR_ORIENT_COMP_MAGN_NORTH:
+	case HID_USAGE_SENSOR_ORIENT_COMP_TRUE_NORTH:
+	case HID_USAGE_SENSOR_ORIENT_MAGN_NORTH:
+	case HID_USAGE_SENSOR_ORIENT_TRUE_NORTH:
+		offset = (usage_id - HID_USAGE_SENSOR_ORIENT_COMP_MAGN_NORTH)
+				+ CHANNEL_SCAN_INDEX_NORTH_MAGN_TILT_COMP;
+	break;
 	default:
 		return -EINVAL;
 	}
-- 
1.9.3

Re: [PATCH v7 0/4] iio: Add support for rotation from north

[Jonathan Cameron]

On 20/07/14 18:57, Reyad Attiyat wrote:
> This series of patches modifies magn-3d driver to handle the rotation
> from north usage. This is done by scanning the report and then building
> the iio arrays (vals and channels) dynamically.
>
> Changes from V6
> Remove sizeof from function hid_sensor_push_data as it is not used or
> passed to iio_push_to_buffer
>
Thanks.  Another zero day bug fix notched up to the Autobuilders before
it went out.

Anyhow, v7 applied and pushed out as testing (again - just in case ;)

J


> Reyad Attiyat (4):
>    iio: Documentation: Add documentation for rotation from north sensor
>      usage attributes
>    iio: types: Added support for rotation from north usage attributes
>    iio: hid-sensor-magn-3d: Scan for usage attributes before setting up
>      iio channels
>    iio: hid-sensor-magn-3d: Add support for rotation from north
>
>   Documentation/ABI/testing/sysfs-bus-iio       |  82 +++++++++++
>   drivers/iio/industrialio-core.c               |   4 +
>   drivers/iio/magnetometer/hid-sensor-magn-3d.c | 199 ++++++++++++++++++++------
>   include/linux/iio/types.h                     |   4 +
>   4 files changed, 245 insertions(+), 44 deletions(-)
>