Re: [PATCH 5/6] iio: hid-sensors: Added device rotation support

[Jonathan Cameron <jic23@kernel.org>]

On 29/04/14 00:51, Srinivas Pandruvada wrote:
> Added usage id processing for device rotation. This uses IIO
> interfaces for triggered buffer to present data to user
> mode.This uses HID sensor framework for registering callback
> events from the sensor hub.
> Data is exported to user space in the form of quaternion rotation
> format.
>
> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Applied to the togreg branch of iio.git

Thanks,
> ---
>   drivers/iio/orientation/Kconfig               |  12 +
>   drivers/iio/orientation/Makefile              |   1 +
>   drivers/iio/orientation/hid-sensor-rotation.c | 348 ++++++++++++++++++++++++++
>   include/linux/hid-sensor-ids.h                |   1 +
>   4 files changed, 362 insertions(+)
>   create mode 100644 drivers/iio/orientation/hid-sensor-rotation.c
>
> diff --git a/drivers/iio/orientation/Kconfig b/drivers/iio/orientation/Kconfig
> index 58c62c8..e3aa1e5 100644
> --- a/drivers/iio/orientation/Kconfig
> +++ b/drivers/iio/orientation/Kconfig
> @@ -16,4 +16,16 @@ config HID_SENSOR_INCLINOMETER_3D
>   	  Say yes here to build support for the HID SENSOR
>   	  Inclinometer 3D.
>
> +config HID_SENSOR_DEVICE_ROTATION
> +	depends on HID_SENSOR_HUB
> +	select IIO_BUFFER
> +	select IIO_TRIGGERED_BUFFER
> +	select HID_SENSOR_IIO_COMMON
> +	select HID_SENSOR_IIO_TRIGGER
> +	tristate "HID Device Rotation"
> +	help
> +	  Say yes here to build support for the HID SENSOR
> +	  device rotation. The output of a device rotation sensor
> +	  is presented using quaternion format.
> +
>   endmenu
> diff --git a/drivers/iio/orientation/Makefile b/drivers/iio/orientation/Makefile
> index 2c97572..4734dab 100644
> --- a/drivers/iio/orientation/Makefile
> +++ b/drivers/iio/orientation/Makefile
> @@ -4,3 +4,4 @@
>
>   # When adding new entries keep the list in alphabetical order
>   obj-$(CONFIG_HID_SENSOR_INCLINOMETER_3D) += hid-sensor-incl-3d.o
> +obj-$(CONFIG_HID_SENSOR_DEVICE_ROTATION) += hid-sensor-rotation.o
> diff --git a/drivers/iio/orientation/hid-sensor-rotation.c b/drivers/iio/orientation/hid-sensor-rotation.c
> new file mode 100644
> index 0000000..51387bb
> --- /dev/null
> +++ b/drivers/iio/orientation/hid-sensor-rotation.c
> @@ -0,0 +1,348 @@
> +/*
> + * HID Sensors Driver
> + * Copyright (c) 2014, Intel Corporation.
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms and conditions of the GNU General Public License,
> + * version 2, as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope it will be useful, but WITHOUT
> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> + * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
> + * more details.
> + */
> +
> +#include <linux/device.h>
> +#include <linux/platform_device.h>
> +#include <linux/module.h>
> +#include <linux/interrupt.h>
> +#include <linux/irq.h>
> +#include <linux/slab.h>
> +#include <linux/hid-sensor-hub.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +#include <linux/iio/buffer.h>
> +#include <linux/iio/trigger_consumer.h>
> +#include <linux/iio/triggered_buffer.h>
> +#include "../common/hid-sensors/hid-sensor-trigger.h"
> +
> +struct dev_rot_state {
> +	struct hid_sensor_hub_callbacks callbacks;
> +	struct hid_sensor_common common_attributes;
> +	struct hid_sensor_hub_attribute_info quaternion;
> +	u32 sampled_vals[4];
> +};
> +
> +/* Channel definitions */
> +static const struct iio_chan_spec dev_rot_channels[] = {
> +	{
> +		.type = IIO_ROT,
> +		.modified = 1,
> +		.channel2 = IIO_MOD_QUATERNION,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> +		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
> +					BIT(IIO_CHAN_INFO_HYSTERESIS)
> +	}
> +};
> +
> +/* Adjust channel real bits based on report descriptor */
> +static void dev_rot_adjust_channel_bit_mask(struct iio_chan_spec *chan,
> +						int size)
> +{
> +	chan->scan_type.sign = 's';
> +	/* Real storage bits will change based on the report desc. */
> +	chan->scan_type.realbits = size * 8;
> +	/* Maximum size of a sample to capture is u32 */
> +	chan->scan_type.storagebits = sizeof(u32) * 8;
> +	chan->scan_type.repeat = 4;
> +}
> +
> +/* Channel read_raw handler */
> +static int dev_rot_read_raw(struct iio_dev *indio_dev,
> +				struct iio_chan_spec const *chan,
> +				int size, int *vals, int *val_len,
> +				long mask)
> +{
> +	struct dev_rot_state *rot_state = iio_priv(indio_dev);
> +	int ret_type;
> +	int i;
> +
> +	vals[0] = 0;
> +	vals[1] = 0;
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		if (size >= 4) {
> +			for (i = 0; i < 4; ++i)
> +				vals[i] = rot_state->sampled_vals[i];
> +			ret_type = IIO_VAL_INT_MULTIPLE;
> +			*val_len =  4;
> +		} else
> +			ret_type = -EINVAL;
> +		break;
> +	case IIO_CHAN_INFO_SAMP_FREQ:
> +		ret_type = hid_sensor_read_samp_freq_value(
> +			&rot_state->common_attributes, &vals[0], &vals[1]);
> +		break;
> +	case IIO_CHAN_INFO_HYSTERESIS:
> +		ret_type = hid_sensor_read_raw_hyst_value(
> +			&rot_state->common_attributes, &vals[0], &vals[1]);
> +		break;
> +	default:
> +		ret_type = -EINVAL;
> +		break;
> +	}
> +
> +	return ret_type;
> +}
> +
> +/* Channel write_raw handler */
> +static int dev_rot_write_raw(struct iio_dev *indio_dev,
> +			       struct iio_chan_spec const *chan,
> +			       int val,
> +			       int val2,
> +			       long mask)
> +{
> +	struct dev_rot_state *rot_state = iio_priv(indio_dev);
> +	int ret;
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_SAMP_FREQ:
> +		ret = hid_sensor_write_samp_freq_value(
> +				&rot_state->common_attributes, val, val2);
> +		break;
> +	case IIO_CHAN_INFO_HYSTERESIS:
> +		ret = hid_sensor_write_raw_hyst_value(
> +				&rot_state->common_attributes, val, val2);
> +		break;
> +	default:
> +		ret = -EINVAL;
> +	}
> +
> +	return ret;
> +}
> +
> +static const struct iio_info dev_rot_info = {
> +	.driver_module = THIS_MODULE,
> +	.read_raw_multi = &dev_rot_read_raw,
> +	.write_raw = &dev_rot_write_raw,
> +};
> +
> +/* Function to push data to buffer */
> +static void hid_sensor_push_data(struct iio_dev *indio_dev, u8 *data, int len)
> +{
> +	dev_dbg(&indio_dev->dev, "hid_sensor_push_data >>\n");
> +	iio_push_to_buffers(indio_dev, (u8 *)data);
> +	dev_dbg(&indio_dev->dev, "hid_sensor_push_data <<\n");
> +
> +}
> +
> +/* Callback handler to send event after all samples are received and captured */
> +static int dev_rot_proc_event(struct hid_sensor_hub_device *hsdev,
> +				unsigned usage_id,
> +				void *priv)
> +{
> +	struct iio_dev *indio_dev = platform_get_drvdata(priv);
> +	struct dev_rot_state *rot_state = iio_priv(indio_dev);
> +
> +	dev_dbg(&indio_dev->dev, "dev_rot_proc_event [%d]\n",
> +				rot_state->common_attributes.data_ready);
> +
> +	if (rot_state->common_attributes.data_ready)
> +		hid_sensor_push_data(indio_dev,
> +				(u8 *)rot_state->sampled_vals,
> +				sizeof(rot_state->sampled_vals));
> +
> +	return 0;
> +}
> +
> +/* Capture samples in local storage */
> +static int dev_rot_capture_sample(struct hid_sensor_hub_device *hsdev,
> +				unsigned usage_id,
> +				size_t raw_len, char *raw_data,
> +				void *priv)
> +{
> +	struct iio_dev *indio_dev = platform_get_drvdata(priv);
> +	struct dev_rot_state *rot_state = iio_priv(indio_dev);
> +
> +	if (usage_id == HID_USAGE_SENSOR_ORIENT_QUATERNION) {
> +		memcpy(rot_state->sampled_vals, raw_data,
> +					sizeof(rot_state->sampled_vals));
> +		dev_dbg(&indio_dev->dev, "Recd Quat len:%zu::%zu\n", raw_len,
> +					sizeof(rot_state->sampled_vals));
> +	}
> +
> +	return 0;
> +}
> +
> +/* Parse report which is specific to an usage id*/
> +static int dev_rot_parse_report(struct platform_device *pdev,
> +				struct hid_sensor_hub_device *hsdev,
> +				struct iio_chan_spec *channels,
> +				unsigned usage_id,
> +				struct dev_rot_state *st)
> +{
> +	int ret;
> +
> +	ret = sensor_hub_input_get_attribute_info(hsdev,
> +				HID_INPUT_REPORT,
> +				usage_id,
> +				HID_USAGE_SENSOR_ORIENT_QUATERNION,
> +				&st->quaternion);
> +	if (ret)
> +		return ret;
> +
> +	dev_rot_adjust_channel_bit_mask(&channels[0],
> +		st->quaternion.size / 4);
> +
> +	dev_dbg(&pdev->dev, "dev_rot %x:%x\n", st->quaternion.index,
> +		st->quaternion.report_id);
> +
> +	dev_dbg(&pdev->dev, "dev_rot: attrib size %d\n",
> +				st->quaternion.size);
> +
> +	/* Set Sensitivity field ids, when there is no individual modifier */
> +	if (st->common_attributes.sensitivity.index < 0) {
> +		sensor_hub_input_get_attribute_info(hsdev,
> +			HID_FEATURE_REPORT, usage_id,
> +			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
> +			HID_USAGE_SENSOR_DATA_ORIENTATION,
> +			&st->common_attributes.sensitivity);
> +		dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
> +			st->common_attributes.sensitivity.index,
> +			st->common_attributes.sensitivity.report_id);
> +	}
> +
> +	return 0;
> +}
> +
> +/* Function to initialize the processing for usage id */
> +static int hid_dev_rot_probe(struct platform_device *pdev)
> +{
> +	int ret;
> +	static char *name = "dev_rotation";
> +	struct iio_dev *indio_dev;
> +	struct dev_rot_state *rot_state;
> +	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
> +	struct iio_chan_spec *channels;
> +
> +	indio_dev = devm_iio_device_alloc(&pdev->dev,
> +					  sizeof(struct dev_rot_state));
> +	if (indio_dev == NULL)
> +		return -ENOMEM;
> +
> +	platform_set_drvdata(pdev, indio_dev);
> +
> +	rot_state = iio_priv(indio_dev);
> +	rot_state->common_attributes.hsdev = hsdev;
> +	rot_state->common_attributes.pdev = pdev;
> +
> +	ret = hid_sensor_parse_common_attributes(hsdev,
> +				HID_USAGE_SENSOR_DEVICE_ORIENTATION,
> +				&rot_state->common_attributes);
> +	if (ret) {
> +		dev_err(&pdev->dev, "failed to setup common attributes\n");
> +		return ret;
> +	}
> +
> +	channels = devm_kmemdup(&pdev->dev, dev_rot_channels,
> +					sizeof(dev_rot_channels), GFP_KERNEL);
> +	if (!channels) {
> +		dev_err(&pdev->dev, "failed to duplicate channels\n");
> +		return -ENOMEM;
> +	}
> +
> +	ret = dev_rot_parse_report(pdev, hsdev, channels,
> +			HID_USAGE_SENSOR_DEVICE_ORIENTATION, rot_state);
> +	if (ret) {
> +		dev_err(&pdev->dev, "failed to setup attributes\n");
> +		return ret;
> +	}
> +
> +	indio_dev->channels = channels;
> +	indio_dev->num_channels = ARRAY_SIZE(dev_rot_channels);
> +	indio_dev->dev.parent = &pdev->dev;
> +	indio_dev->info = &dev_rot_info;
> +	indio_dev->name = name;
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +
> +	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
> +		NULL, NULL);
> +	if (ret) {
> +		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
> +		return ret;
> +	}
> +	rot_state->common_attributes.data_ready = false;
> +	ret = hid_sensor_setup_trigger(indio_dev, name,
> +					&rot_state->common_attributes);
> +	if (ret) {
> +		dev_err(&pdev->dev, "trigger setup failed\n");
> +		goto error_unreg_buffer_funcs;
> +	}
> +
> +	ret = iio_device_register(indio_dev);
> +	if (ret) {
> +		dev_err(&pdev->dev, "device register failed\n");
> +		goto error_remove_trigger;
> +	}
> +
> +	rot_state->callbacks.send_event = dev_rot_proc_event;
> +	rot_state->callbacks.capture_sample = dev_rot_capture_sample;
> +	rot_state->callbacks.pdev = pdev;
> +	ret = sensor_hub_register_callback(hsdev,
> +					HID_USAGE_SENSOR_DEVICE_ORIENTATION,
> +					&rot_state->callbacks);
> +	if (ret) {
> +		dev_err(&pdev->dev, "callback reg failed\n");
> +		goto error_iio_unreg;
> +	}
> +
> +	return 0;
> +
> +error_iio_unreg:
> +	iio_device_unregister(indio_dev);
> +error_remove_trigger:
> +	hid_sensor_remove_trigger(&rot_state->common_attributes);
> +error_unreg_buffer_funcs:
> +	iio_triggered_buffer_cleanup(indio_dev);
> +	return ret;
> +}
> +
> +/* Function to deinitialize the processing for usage id */
> +static int hid_dev_rot_remove(struct platform_device *pdev)
> +{
> +	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
> +	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
> +	struct dev_rot_state *rot_state = iio_priv(indio_dev);
> +
> +	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_DEVICE_ORIENTATION);
> +	iio_device_unregister(indio_dev);
> +	hid_sensor_remove_trigger(&rot_state->common_attributes);
> +	iio_triggered_buffer_cleanup(indio_dev);
> +
> +	return 0;
> +}
> +
> +static struct platform_device_id hid_dev_rot_ids[] = {
> +	{
> +		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
> +		.name = "HID-SENSOR-20008a",
> +	},
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(platform, hid_dev_rot_ids);
> +
> +static struct platform_driver hid_dev_rot_platform_driver = {
> +	.id_table = hid_dev_rot_ids,
> +	.driver = {
> +		.name	= KBUILD_MODNAME,
> +		.owner	= THIS_MODULE,
> +	},
> +	.probe		= hid_dev_rot_probe,
> +	.remove		= hid_dev_rot_remove,
> +};
> +module_platform_driver(hid_dev_rot_platform_driver);
> +
> +MODULE_DESCRIPTION("HID Sensor Device Rotation");
> +MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
> +MODULE_LICENSE("GPL");
> diff --git a/include/linux/hid-sensor-ids.h b/include/linux/hid-sensor-ids.h
> index 14ead9e..109f0e6 100644
> --- a/include/linux/hid-sensor-ids.h
> +++ b/include/linux/hid-sensor-ids.h
> @@ -76,6 +76,7 @@
>   #define HID_USAGE_SENSOR_ORIENT_TILT_Y				0x200480
>   #define HID_USAGE_SENSOR_ORIENT_TILT_Z				0x200481
>
> +#define HID_USAGE_SENSOR_DEVICE_ORIENTATION			0x20008A
>   #define HID_USAGE_SENSOR_ORIENT_ROTATION_MATRIX			0x200482
>   #define HID_USAGE_SENSOR_ORIENT_QUATERNION			0x200483
>   #define HID_USAGE_SENSOR_ORIENT_MAGN_FLUX			0x200484
>