[PATCH v3 1/2] iio: Add channel for Gravity

[PATCH v3 1/2] iio: Add channel for Gravity

[Song Hongyan]

Add new channel types support for gravity sensor.

Gravity sensor provides an application-level or physical collection that
identifies a device that measures exclusively the force of Earth's
gravity along any number of axes.

More information can be found in:
http://www.usb.org/developers/hidpage/HUTRR59_-_Usages_for_Wearables.pdf

Signed-off-by: Song Hongyan <hongyan.song-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
---
changes: patch rebase

 Documentation/ABI/testing/sysfs-bus-iio | 10 ++++++++++
 drivers/iio/industrialio-core.c         |  1 +
 include/uapi/linux/iio/types.h          |  1 +
 tools/iio/iio_event_monitor.c           |  2 ++
 4 files changed, 14 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio
index b8f220f..ed5bc2b 100644
--- a/Documentation/ABI/testing/sysfs-bus-iio
+++ b/Documentation/ABI/testing/sysfs-bus-iio
@@ -170,6 +170,16 @@ Description:
 		Has all of the equivalent parameters as per voltageY. Units
 		after application of scale and offset are m/s^2.
 
+What:		/sys/bus/iio/devices/iio:deviceX/in_gravity_x_raw
+What:		/sys/bus/iio/devices/iio:deviceX/in_gravity_y_raw
+What:		/sys/bus/iio/devices/iio:deviceX/in_gravity_z_raw
+KernelVersion:	4.11
+Contact:	linux-iio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
+Description:
+		Gravity in direction x, y or z (may be arbitrarily assigned
+		but should match other such assignments on device).
+		Units after application of scale and offset are m/s^2.
+
 What:		/sys/bus/iio/devices/iio:deviceX/in_anglvel_x_raw
 What:		/sys/bus/iio/devices/iio:deviceX/in_anglvel_y_raw
 What:		/sys/bus/iio/devices/iio:deviceX/in_anglvel_z_raw
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index aaca428..c601698 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -83,6 +83,7 @@ struct bus_type iio_bus_type = {
 	[IIO_ELECTRICALCONDUCTIVITY] = "electricalconductivity",
 	[IIO_COUNT] = "count",
 	[IIO_INDEX] = "index",
+	[IIO_GRAVITY]  = "gravity",
 };
 
 static const char * const iio_modifier_names[] = {
diff --git a/include/uapi/linux/iio/types.h b/include/uapi/linux/iio/types.h
index e54d14a..ffafd6c 100644
--- a/include/uapi/linux/iio/types.h
+++ b/include/uapi/linux/iio/types.h
@@ -42,6 +42,7 @@ enum iio_chan_type {
 	IIO_ELECTRICALCONDUCTIVITY,
 	IIO_COUNT,
 	IIO_INDEX,
+	IIO_GRAVITY,
 };
 
 enum iio_modifier {
diff --git a/tools/iio/iio_event_monitor.c b/tools/iio/iio_event_monitor.c
index d9b7e0f..b61245e 100644
--- a/tools/iio/iio_event_monitor.c
+++ b/tools/iio/iio_event_monitor.c
@@ -57,6 +57,7 @@
 	[IIO_RESISTANCE] = "resistance",
 	[IIO_PH] = "ph",
 	[IIO_UVINDEX] = "uvindex",
+	[IIO_GRAVITY] = "gravity",
 };
 
 static const char * const iio_ev_type_text[] = {
@@ -149,6 +150,7 @@ static bool event_is_known(struct iio_event_data *event)
 	case IIO_RESISTANCE:
 	case IIO_PH:
 	case IIO_UVINDEX:
+	case IIO_GRAVITY:
 		break;
 	default:
 		return false;
-- 
1.9.1

[PATCH v3 2/2] iio: Add gravity sensor support

[Song Hongyan]

Gravity sensor is a soft sensor, which derives value from
standard accelerometer device by filtering out the acceleration
which is not caused by gravity.

Gravity sensor provides a three dimensional vector indicating
the direction and magnitude of gravity. Typically, this sensor
is used to determine the device's relative orientation in space.
The units and the coordinate system is the same as the one used by
the acceleration sensor.
When a device is at rest, the output of the gravity sensor should
be identical to that of the accelerometer.

More information can be found in:
http://www.usb.org/developers/hidpage/HUTRR59_-_Usages_for_Wearables.pdf

Gravity sensor and accelerometer have similar channels and
share channel usage ids. So the most of the code for accel_3d
can be reused.

Signed-off-by: Song Hongyan <hongyan.song-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
---
no change from v2

 drivers/iio/accel/hid-sensor-accel-3d.c | 74 +++++++++++++++++++++++++++------
 include/linux/hid-sensor-ids.h          |  3 ++
 2 files changed, 64 insertions(+), 13 deletions(-)

diff --git a/drivers/iio/accel/hid-sensor-accel-3d.c b/drivers/iio/accel/hid-sensor-accel-3d.c
index ab1e238..9edd574 100644
--- a/drivers/iio/accel/hid-sensor-accel-3d.c
+++ b/drivers/iio/accel/hid-sensor-accel-3d.c
@@ -90,6 +90,41 @@ struct accel_3d_state {
 	}
 };
 
+/* Channel definitions */
+static const struct iio_chan_spec gravity_channels[] = {
+	{
+		.type = IIO_GRAVITY,
+		.modified = 1,
+		.channel2 = IIO_MOD_X,
+		.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),
+		.scan_index = CHANNEL_SCAN_INDEX_X,
+	}, {
+		.type = IIO_GRAVITY,
+		.modified = 1,
+		.channel2 = IIO_MOD_Y,
+		.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),
+		.scan_index = CHANNEL_SCAN_INDEX_Y,
+	}, {
+		.type = IIO_GRAVITY,
+		.modified = 1,
+		.channel2 = IIO_MOD_Z,
+		.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),
+		.scan_index = CHANNEL_SCAN_INDEX_Z,
+	}
+};
+
 /* Adjust channel real bits based on report descriptor */
 static void accel_3d_adjust_channel_bit_mask(struct iio_chan_spec *channels,
 						int channel, int size)
@@ -111,6 +146,8 @@ static int accel_3d_read_raw(struct iio_dev *indio_dev,
 	int report_id = -1;
 	u32 address;
 	int ret_type;
+	struct hid_sensor_hub_device *hsdev =
+					accel_state->common_attributes.hsdev;
 
 	*val = 0;
 	*val2 = 0;
@@ -122,8 +159,7 @@ static int accel_3d_read_raw(struct iio_dev *indio_dev,
 		if (report_id >= 0)
 			*val = sensor_hub_input_attr_get_raw_value(
 					accel_state->common_attributes.hsdev,
-					HID_USAGE_SENSOR_ACCEL_3D, address,
-					report_id,
+					hsdev->usage, address, report_id,
 					SENSOR_HUB_SYNC);
 		else {
 			*val = 0;
@@ -272,7 +308,7 @@ static int accel_3d_parse_report(struct platform_device *pdev,
 			st->accel[2].index, st->accel[2].report_id);
 
 	st->scale_precision = hid_sensor_format_scale(
-				HID_USAGE_SENSOR_ACCEL_3D,
+				hsdev->usage,
 				&st->accel[CHANNEL_SCAN_INDEX_X],
 				&st->scale_pre_decml, &st->scale_post_decml);
 
@@ -295,9 +331,12 @@ static int accel_3d_parse_report(struct platform_device *pdev,
 static int hid_accel_3d_probe(struct platform_device *pdev)
 {
 	int ret = 0;
-	static const char *name = "accel_3d";
+	static const char *name;
 	struct iio_dev *indio_dev;
 	struct accel_3d_state *accel_state;
+	const struct iio_chan_spec *channel_spec;
+	int channel_size;
+
 	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
 
 	indio_dev = devm_iio_device_alloc(&pdev->dev,
@@ -311,24 +350,30 @@ static int hid_accel_3d_probe(struct platform_device *pdev)
 	accel_state->common_attributes.hsdev = hsdev;
 	accel_state->common_attributes.pdev = pdev;
 
-	ret = hid_sensor_parse_common_attributes(hsdev,
-					HID_USAGE_SENSOR_ACCEL_3D,
+	if (hsdev->usage == HID_USAGE_SENSOR_ACCEL_3D) {
+		name = "accel_3d";
+		channel_spec = accel_3d_channels;
+		channel_size = sizeof(accel_3d_channels);
+	} else {
+		name = "gravity";
+		channel_spec = gravity_channels;
+		channel_size = sizeof(gravity_channels);
+	}
+	ret = hid_sensor_parse_common_attributes(hsdev, hsdev->usage,
 					&accel_state->common_attributes);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to setup common attributes\n");
 		return ret;
 	}
+	indio_dev->channels = kmemdup(channel_spec, channel_size, GFP_KERNEL);
 
-	indio_dev->channels = kmemdup(accel_3d_channels,
-				      sizeof(accel_3d_channels), GFP_KERNEL);
 	if (!indio_dev->channels) {
 		dev_err(&pdev->dev, "failed to duplicate channels\n");
 		return -ENOMEM;
 	}
-
 	ret = accel_3d_parse_report(pdev, hsdev,
-				    (struct iio_chan_spec *)indio_dev->channels,
-				    HID_USAGE_SENSOR_ACCEL_3D, accel_state);
+				(struct iio_chan_spec *)indio_dev->channels,
+				hsdev->usage, accel_state);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to setup attributes\n");
 		goto error_free_dev_mem;
@@ -363,7 +408,7 @@ static int hid_accel_3d_probe(struct platform_device *pdev)
 	accel_state->callbacks.send_event = accel_3d_proc_event;
 	accel_state->callbacks.capture_sample = accel_3d_capture_sample;
 	accel_state->callbacks.pdev = pdev;
-	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_ACCEL_3D,
+	ret = sensor_hub_register_callback(hsdev, hsdev->usage,
 					&accel_state->callbacks);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "callback reg failed\n");
@@ -390,7 +435,7 @@ static int hid_accel_3d_remove(struct platform_device *pdev)
 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 	struct accel_3d_state *accel_state = iio_priv(indio_dev);
 
-	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_ACCEL_3D);
+	sensor_hub_remove_callback(hsdev, hsdev->usage);
 	iio_device_unregister(indio_dev);
 	hid_sensor_remove_trigger(&accel_state->common_attributes);
 	iio_triggered_buffer_cleanup(indio_dev);
@@ -404,6 +449,9 @@ static int hid_accel_3d_remove(struct platform_device *pdev)
 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
 		.name = "HID-SENSOR-200073",
 	},
+	{	/* gravity sensor */
+		.name = "HID-SENSOR-20007b",
+	},
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(platform, hid_accel_3d_ids);
diff --git a/include/linux/hid-sensor-ids.h b/include/linux/hid-sensor-ids.h
index f2ee90a..b6778fd2 100644
--- a/include/linux/hid-sensor-ids.h
+++ b/include/linux/hid-sensor-ids.h
@@ -52,6 +52,9 @@
 #define HID_USAGE_SENSOR_ANGL_VELOCITY_Y_AXIS			0x200458
 #define HID_USAGE_SENSOR_ANGL_VELOCITY_Z_AXIS			0x200459
 
+/* Gravity vector */
+#define HID_USAGE_SENSOR_GRAVITY_VECTOR				0x20007B
+
 /* ORIENTATION: Compass 3D: (200083) */
 #define HID_USAGE_SENSOR_COMPASS_3D				0x200083
 #define HID_USAGE_SENSOR_DATA_ORIENTATION			0x200470
-- 
1.9.1

Re: [PATCH v3 1/2] iio: Add channel for Gravity

[Jonathan Cameron]

On 05/01/17 10:24, Song Hongyan wrote:
> Add new channel types support for gravity sensor.
> 
> Gravity sensor provides an application-level or physical collection that
> identifies a device that measures exclusively the force of Earth's
> gravity along any number of axes.
> 
> More information can be found in:
> http://www.usb.org/developers/hidpage/HUTRR59_-_Usages_for_Wearables.pdf
> 
> Signed-off-by: Song Hongyan <hongyan.song-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Applied to the togreg branch of iio.git. Will push out as testing sometime soon when
I have a decent net connection.

Thanks,

Jonathan
> ---
> changes: patch rebase
> 
>  Documentation/ABI/testing/sysfs-bus-iio | 10 ++++++++++
>  drivers/iio/industrialio-core.c         |  1 +
>  include/uapi/linux/iio/types.h          |  1 +
>  tools/iio/iio_event_monitor.c           |  2 ++
>  4 files changed, 14 insertions(+)
> 
> diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio
> index b8f220f..ed5bc2b 100644
> --- a/Documentation/ABI/testing/sysfs-bus-iio
> +++ b/Documentation/ABI/testing/sysfs-bus-iio
> @@ -170,6 +170,16 @@ Description:
>  		Has all of the equivalent parameters as per voltageY. Units
>  		after application of scale and offset are m/s^2.
>  
> +What:		/sys/bus/iio/devices/iio:deviceX/in_gravity_x_raw
> +What:		/sys/bus/iio/devices/iio:deviceX/in_gravity_y_raw
> +What:		/sys/bus/iio/devices/iio:deviceX/in_gravity_z_raw
> +KernelVersion:	4.11
> +Contact:	linux-iio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
> +Description:
> +		Gravity in direction x, y or z (may be arbitrarily assigned
> +		but should match other such assignments on device).
> +		Units after application of scale and offset are m/s^2.
> +
>  What:		/sys/bus/iio/devices/iio:deviceX/in_anglvel_x_raw
>  What:		/sys/bus/iio/devices/iio:deviceX/in_anglvel_y_raw
>  What:		/sys/bus/iio/devices/iio:deviceX/in_anglvel_z_raw
> diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
> index aaca428..c601698 100644
> --- a/drivers/iio/industrialio-core.c
> +++ b/drivers/iio/industrialio-core.c
> @@ -83,6 +83,7 @@ struct bus_type iio_bus_type = {
>  	[IIO_ELECTRICALCONDUCTIVITY] = "electricalconductivity",
>  	[IIO_COUNT] = "count",
>  	[IIO_INDEX] = "index",
> +	[IIO_GRAVITY]  = "gravity",
>  };
>  
>  static const char * const iio_modifier_names[] = {
> diff --git a/include/uapi/linux/iio/types.h b/include/uapi/linux/iio/types.h
> index e54d14a..ffafd6c 100644
> --- a/include/uapi/linux/iio/types.h
> +++ b/include/uapi/linux/iio/types.h
> @@ -42,6 +42,7 @@ enum iio_chan_type {
>  	IIO_ELECTRICALCONDUCTIVITY,
>  	IIO_COUNT,
>  	IIO_INDEX,
> +	IIO_GRAVITY,
j>  };
>  
>  enum iio_modifier {
> diff --git a/tools/iio/iio_event_monitor.c b/tools/iio/iio_event_monitor.c
> index d9b7e0f..b61245e 100644
> --- a/tools/iio/iio_event_monitor.c
> +++ b/tools/iio/iio_event_monitor.c
> @@ -57,6 +57,7 @@
>  	[IIO_RESISTANCE] = "resistance",
>  	[IIO_PH] = "ph",
>  	[IIO_UVINDEX] = "uvindex",
> +	[IIO_GRAVITY] = "gravity",
>  };
>  
>  static const char * const iio_ev_type_text[] = {
> @@ -149,6 +150,7 @@ static bool event_is_known(struct iio_event_data *event)
>  	case IIO_RESISTANCE:
>  	case IIO_PH:
>  	case IIO_UVINDEX:
> +	case IIO_GRAVITY:
>  		break;
>  	default:
>  		return false;
>