Re: [PATCH v3] iio: cros_ec_light_prox: add ChromeOS EC Light and Proximity Sensors

[Jonathan Cameron]

On 30/01/17 17:07, Enric Balletbo i Serra wrote:
> From: Gwendal Grignou <gwendal@xxxxxxxxxxxx>
> 
> Handle Light and Proximity sensors presented by the ChromeOS EC Sensor hub.
> Creates an IIO device for each functions.
> 
> Signed-off-by: Gwendal Grignou <gwendal@xxxxxxxxxxxx>
> Signed-off-by: Guenter Roeck <groeck@xxxxxxxxxxxx>
> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx>
Applied to the togreg branch of iio.git and pushed out as testing for the
autobuilders to play with it.

Probably just missed up coming merge window.

Thanks,

Jonathan
> ---
> Changes since v3:
>  - Move to iio/light directory.
>  - Revert a change made in v2. Use PROCESSED for light and RAW for proximity
>    as discussed.
>  - Removed BIT(IIO_CHAN_INFO_SCALE) (Jonathan: 'For the proximity it's normal
>    to provide raw with no known scale')
> Changes since v2:
>  - Depends on IIO_CROS_EC_SENSORS_CORE instead of select
>  - Use PROCESSED for light and proximity, remove SCALE
> 
>  drivers/iio/light/Kconfig              |  10 ++
>  drivers/iio/light/Makefile             |   1 +
>  drivers/iio/light/cros_ec_light_prox.c | 289 +++++++++++++++++++++++++++++++++
>  3 files changed, 300 insertions(+)
>  create mode 100644 drivers/iio/light/cros_ec_light_prox.c
> 
> diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
> index 298ea50..71c93b5e 100644
> --- a/drivers/iio/light/Kconfig
> +++ b/drivers/iio/light/Kconfig
> @@ -126,6 +126,16 @@ config CM36651
>  	 To compile this driver as a module, choose M here:
>  	 the module will be called cm36651.
>  
> +config IIO_CROS_EC_LIGHT_PROX
> +	tristate "ChromeOS EC Light and Proximity Sensors"
> +	depends on IIO_CROS_EC_SENSORS_CORE
> +	help
> +	  Say Y here if you use the light and proximity sensors
> +	  presented by the ChromeOS EC Sensor hub.
> +
> +	  To compile this driver as a module, choose M here:
> +	  the module will be called cros_ec_light_prox.
> +
>  config GP2AP020A00F
>  	tristate "Sharp GP2AP020A00F Proximity/ALS sensor"
>  	depends on I2C
> diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
> index 4de5200..844deeb 100644
> --- a/drivers/iio/light/Makefile
> +++ b/drivers/iio/light/Makefile
> @@ -14,6 +14,7 @@ obj-$(CONFIG_CM32181)		+= cm32181.o
>  obj-$(CONFIG_CM3232)		+= cm3232.o
>  obj-$(CONFIG_CM3323)		+= cm3323.o
>  obj-$(CONFIG_CM36651)		+= cm36651.o
> +obj-$(CONFIG_IIO_CROS_EC_LIGHT_PROX) += cros_ec_light_prox.o
>  obj-$(CONFIG_GP2AP020A00F)	+= gp2ap020a00f.o
>  obj-$(CONFIG_HID_SENSOR_ALS)	+= hid-sensor-als.o
>  obj-$(CONFIG_HID_SENSOR_PROX)	+= hid-sensor-prox.o
> diff --git a/drivers/iio/light/cros_ec_light_prox.c b/drivers/iio/light/cros_ec_light_prox.c
> new file mode 100644
> index 0000000..7217223
> --- /dev/null
> +++ b/drivers/iio/light/cros_ec_light_prox.c
> @@ -0,0 +1,289 @@
> +/*
> + * cros_ec_light_prox - Driver for light and prox sensors behing CrosEC.
> + *
> + * Copyright (C) 2017 Google, Inc
> + *
> + * This software is licensed under the terms of the GNU General Public
> + * License version 2, as published by the Free Software Foundation, and
> + * may be copied, distributed, and modified under those terms.
> + *
> + * This program is distributed in the hope that 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/delay.h>
> +#include <linux/device.h>
> +#include <linux/iio/buffer.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/kfifo_buf.h>
> +#include <linux/iio/trigger.h>
> +#include <linux/iio/triggered_buffer.h>
> +#include <linux/iio/trigger_consumer.h>
> +#include <linux/kernel.h>
> +#include <linux/mfd/cros_ec.h>
> +#include <linux/mfd/cros_ec_commands.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +#include <linux/sysfs.h>
> +
> +#include "../common/cros_ec_sensors/cros_ec_sensors_core.h"
> +
> +/*
> + * We only represent one entry for light or proximity. EC is merging different
> + * light sensors to return the what the eye would see. For proximity, we
> + * currently support only one light source.
> + */
> +#define CROS_EC_LIGHT_PROX_MAX_CHANNELS (1 + 1)
> +
> +/* State data for ec_sensors iio driver. */
> +struct cros_ec_light_prox_state {
> +	/* Shared by all sensors */
> +	struct cros_ec_sensors_core_state core;
> +
> +	struct iio_chan_spec channels[CROS_EC_LIGHT_PROX_MAX_CHANNELS];
> +};
> +
> +static int cros_ec_light_prox_read(struct iio_dev *indio_dev,
> +				   struct iio_chan_spec const *chan,
> +				   int *val, int *val2, long mask)
> +{
> +	struct cros_ec_light_prox_state *st = iio_priv(indio_dev);
> +	u16 data = 0;
> +	s64 val64;
> +	int ret = IIO_VAL_INT;
> +	int idx = chan->scan_index;
> +
> +	mutex_lock(&st->core.cmd_lock);
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		if (chan->type == IIO_PROXIMITY) {
> +			if (cros_ec_sensors_read_cmd(indio_dev, 1 << idx,
> +						     (s16 *)&data) < 0) {
> +				ret = -EIO;
> +				break;
> +			}
> +			*val = data;
> +		} else {
> +			ret = -EINVAL;
> +		}
> +		break;
> +	case IIO_CHAN_INFO_PROCESSED:
> +		if (chan->type == IIO_LIGHT) {
> +			if (cros_ec_sensors_read_cmd(indio_dev, 1 << idx,
> +						     (s16 *)&data) < 0) {
> +				ret = -EIO;
> +				break;
> +			}
> +			/*
> +			 * The data coming from the light sensor is
> +			 * pre-processed and represents the ambient light
> +			 * illuminance reading expressed in lux.
> +			 */
> +			*val = data;
> +			ret = IIO_VAL_INT;
> +		} else {
> +			ret = -EINVAL;
> +		}
> +		break;
> +	case IIO_CHAN_INFO_CALIBBIAS:
> +		st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_OFFSET;
> +		st->core.param.sensor_offset.flags = 0;
> +
> +		if (cros_ec_motion_send_host_cmd(&st->core, 0)) {
> +			ret = -EIO;
> +			break;
> +		}
> +
> +		/* Save values */
> +		st->core.calib[0] = st->core.resp->sensor_offset.offset[0];
> +
> +		*val = st->core.calib[idx];
> +		break;
> +	case IIO_CHAN_INFO_CALIBSCALE:
> +		/*
> +		 * RANGE is used for calibration
> +		 * scale is a number x.y, where x is coded on 16 bits,
> +		 * y coded on 16 bits, between 0 and 9999.
> +		 */
> +		st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_RANGE;
> +		st->core.param.sensor_range.data = EC_MOTION_SENSE_NO_VALUE;
> +
> +		if (cros_ec_motion_send_host_cmd(&st->core, 0)) {
> +			ret = -EIO;
> +			break;
> +		}
> +
> +		val64 = st->core.resp->sensor_range.ret;
> +		*val = val64 >> 16;
> +		*val2 = (val64 & 0xffff) * 100;
> +		ret = IIO_VAL_INT_PLUS_MICRO;
> +		break;
> +	default:
> +		ret = cros_ec_sensors_core_read(&st->core, chan, val, val2,
> +						mask);
> +		break;
> +	}
> +
> +	mutex_unlock(&st->core.cmd_lock);
> +
> +	return ret;
> +}
> +
> +static int cros_ec_light_prox_write(struct iio_dev *indio_dev,
> +			       struct iio_chan_spec const *chan,
> +			       int val, int val2, long mask)
> +{
> +	struct cros_ec_light_prox_state *st = iio_priv(indio_dev);
> +	int ret = 0;
> +	int idx = chan->scan_index;
> +
> +	mutex_lock(&st->core.cmd_lock);
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_CALIBBIAS:
> +		st->core.calib[idx] = val;
> +		/* Send to EC for each axis, even if not complete */
> +		st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_OFFSET;
> +		st->core.param.sensor_offset.flags = MOTION_SENSE_SET_OFFSET;
> +		st->core.param.sensor_offset.offset[0] = st->core.calib[0];
> +		st->core.param.sensor_offset.temp =
> +					EC_MOTION_SENSE_INVALID_CALIB_TEMP;
> +		if (cros_ec_motion_send_host_cmd(&st->core, 0))
> +			ret = -EIO;
> +		break;
> +	case IIO_CHAN_INFO_CALIBSCALE:
> +		st->core.param.cmd = MOTIONSENSE_CMD_SENSOR_RANGE;
> +		st->core.param.sensor_range.data = (val << 16) | (val2 / 100);
> +		if (cros_ec_motion_send_host_cmd(&st->core, 0))
> +			ret = -EIO;
> +		break;
> +	default:
> +		ret = cros_ec_sensors_core_write(&st->core, chan, val, val2,
> +						 mask);
> +		break;
> +	}
> +
> +	mutex_unlock(&st->core.cmd_lock);
> +
> +	return ret;
> +}
> +
> +static const struct iio_info cros_ec_light_prox_info = {
> +	.read_raw = &cros_ec_light_prox_read,
> +	.write_raw = &cros_ec_light_prox_write,
> +	.driver_module = THIS_MODULE,
> +};
> +
> +static int cros_ec_light_prox_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct cros_ec_dev *ec_dev = dev_get_drvdata(dev->parent);
> +	struct cros_ec_device *ec_device;
> +	struct iio_dev *indio_dev;
> +	struct cros_ec_light_prox_state *state;
> +	struct iio_chan_spec *channel;
> +	int ret;
> +
> +	if (!ec_dev || !ec_dev->ec_dev) {
> +		dev_warn(dev, "No CROS EC device found.\n");
> +		return -EINVAL;
> +	}
> +	ec_device = ec_dev->ec_dev;
> +
> +	indio_dev = devm_iio_device_alloc(dev, sizeof(*state));
> +	if (!indio_dev)
> +		return -ENOMEM;
> +
> +	ret = cros_ec_sensors_core_init(pdev, indio_dev, true);
> +	if (ret)
> +		return ret;
> +
> +	indio_dev->info = &cros_ec_light_prox_info;
> +	state = iio_priv(indio_dev);
> +	state->core.type = state->core.resp->info.type;
> +	state->core.loc = state->core.resp->info.location;
> +	channel = state->channels;
> +
> +	/* Common part */
> +	channel->info_mask_shared_by_all =
> +		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
> +		BIT(IIO_CHAN_INFO_FREQUENCY);
> +	channel->scan_type.realbits = CROS_EC_SENSOR_BITS;
> +	channel->scan_type.storagebits = CROS_EC_SENSOR_BITS;
> +	channel->scan_type.shift = 0;
> +	channel->scan_index = 0;
> +	channel->ext_info = cros_ec_sensors_ext_info;
> +	channel->scan_type.sign = 'u';
> +
> +	state->core.calib[0] = 0;
> +
> +	/* Sensor specific */
> +	switch (state->core.type) {
> +	case MOTIONSENSE_TYPE_LIGHT:
> +		channel->type = IIO_LIGHT;
> +		channel->info_mask_separate =
> +			BIT(IIO_CHAN_INFO_PROCESSED) |
> +			BIT(IIO_CHAN_INFO_CALIBBIAS) |
> +			BIT(IIO_CHAN_INFO_CALIBSCALE);
> +		break;
> +	case MOTIONSENSE_TYPE_PROX:
> +		channel->type = IIO_PROXIMITY;
> +		channel->info_mask_separate =
> +			BIT(IIO_CHAN_INFO_RAW) |
> +			BIT(IIO_CHAN_INFO_CALIBBIAS) |
> +			BIT(IIO_CHAN_INFO_CALIBSCALE);
> +		break;
> +	default:
> +		dev_warn(dev, "Unknown motion sensor\n");
> +		return -EINVAL;
> +	}
> +
> +	/* Timestamp */
> +	channel++;
> +	channel->type = IIO_TIMESTAMP;
> +	channel->channel = -1;
> +	channel->scan_index = 1;
> +	channel->scan_type.sign = 's';
> +	channel->scan_type.realbits = 64;
> +	channel->scan_type.storagebits = 64;
> +
> +	indio_dev->channels = state->channels;
> +
> +	indio_dev->num_channels = CROS_EC_LIGHT_PROX_MAX_CHANNELS;
> +
> +	state->core.read_ec_sensors_data = cros_ec_sensors_read_cmd;
> +
> +	ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
> +					      cros_ec_sensors_capture, NULL);
> +	if (ret)
> +		return ret;
> +
> +	return devm_iio_device_register(dev, indio_dev);
> +}
> +
> +static const struct platform_device_id cros_ec_light_prox_ids[] = {
> +	{
> +		.name = "cros-ec-prox",
> +	},
> +	{
> +		.name = "cros-ec-light",
> +	},
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(platform, cros_ec_light_prox_ids);
> +
> +static struct platform_driver cros_ec_light_prox_platform_driver = {
> +	.driver = {
> +		.name	= "cros-ec-light-prox",
> +	},
> +	.probe		= cros_ec_light_prox_probe,
> +	.id_table	= cros_ec_light_prox_ids,
> +};
> +module_platform_driver(cros_ec_light_prox_platform_driver);
> +
> +MODULE_DESCRIPTION("ChromeOS EC light/proximity sensors driver");
> +MODULE_LICENSE("GPL v2");
>