Re: [PATCH v4 4/4] platform/chrome: cros_ec_dev - Register cros-ec sensors

[Jonathan Cameron <jic23@kernel.org>]

On 01/08/16 10:54, Enric Balletbo i Serra wrote:
> Check whether the ChromeOS Embedded Controller is a sensor hub and in
> such case issue a command to get the number of sensors and register them
> all.
> 
> Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
> Reviewed-by: Guenter Roeck <groeck@chromium.org>
> ---
> 
> Changes since v3:
>  - Remove Unnecessary ( ) around 'ret < 0'.
>  - Add Reviewed-by tag
> 
>  .../iio/common/cros_ec_sensors/cros_ec_sensors.c   |   4 +-
>  drivers/platform/chrome/cros_ec_dev.c              | 122 +++++++++++++++++++++
>  2 files changed, 124 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
> index 48edeba..d6c372b 100644
> --- a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
> +++ b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
> @@ -51,7 +51,7 @@ static int cros_ec_sensors_read(struct iio_dev *indio_dev,
>  	s16 data = 0;
>  	s64 val64;
>  	int i;
> -	int ret = IIO_VAL_INT;
> +	int ret;
>  	int idx = chan->scan_index;
>  
>  	mutex_lock(&st->core.cmd_lock);
> @@ -137,7 +137,7 @@ static int cros_ec_sensors_write(struct iio_dev *indio_dev,
>  {
>  	struct cros_ec_sensors_state *st = iio_priv(indio_dev);
>  	int i;
> -	int ret = 0;
> +	int ret;
>  	int idx = chan->scan_index;
*raises eyebrows*

Enough said?

Was wondering why this patch had strayed into the IIO files.


>  
>  	mutex_lock(&st->core.cmd_lock);
> diff --git a/drivers/platform/chrome/cros_ec_dev.c b/drivers/platform/chrome/cros_ec_dev.c
> index 7eb5307..47268ec 100644
> --- a/drivers/platform/chrome/cros_ec_dev.c
> +++ b/drivers/platform/chrome/cros_ec_dev.c
> @@ -18,6 +18,7 @@
>   */
>  
>  #include <linux/fs.h>
> +#include <linux/mfd/core.h>
>  #include <linux/module.h>
>  #include <linux/platform_device.h>
>  #include <linux/slab.h>
> @@ -265,6 +266,123 @@ static void __remove(struct device *dev)
>  	kfree(ec);
>  }
>  
> +static void cros_ec_sensors_register(struct cros_ec_dev *ec)
> +{
> +	/*
> +	 * Issue a command to get the number of sensor reported.
> +	 * Build an array of sensors driver and register them all.
> +	 */
> +	int ret, i, id, sensor_num;
> +	struct mfd_cell *sensor_cells;
> +	struct cros_ec_sensor_platform *sensor_platforms;
> +	int sensor_type[MOTIONSENSE_TYPE_MAX];
> +	struct ec_params_motion_sense *params;
> +	struct ec_response_motion_sense *resp;
> +	struct cros_ec_command *msg;
> +
> +	msg = kzalloc(sizeof(struct cros_ec_command) +
> +		      max(sizeof(*params), sizeof(*resp)), GFP_KERNEL);
> +	if (msg == NULL)
> +		return;
> +
> +	msg->version = 2;
> +	msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
> +	msg->outsize = sizeof(*params);
> +	msg->insize = sizeof(*resp);
> +
> +	params = (struct ec_params_motion_sense *)msg->data;
> +	params->cmd = MOTIONSENSE_CMD_DUMP;
> +
> +	ret = cros_ec_cmd_xfer(ec->ec_dev, msg);
> +	if (ret < 0 || msg->result != EC_RES_SUCCESS) {
> +		dev_warn(ec->dev, "cannot get EC sensor information: %d/%d\n",
> +			 ret, msg->result);
> +		goto error;
> +	}
> +
> +	resp = (struct ec_response_motion_sense *)msg->data;
> +	sensor_num = resp->dump.sensor_count;
> +	/* Allocate 2 extra sensors in case lid angle or FIFO are needed */
> +	sensor_cells = kzalloc(sizeof(struct mfd_cell) * (sensor_num + 2),
> +			       GFP_KERNEL);
> +	if (sensor_cells == NULL)
> +		goto error;
> +
> +	sensor_platforms = kzalloc(sizeof(struct cros_ec_sensor_platform) *
> +		  (sensor_num + 1), GFP_KERNEL);
> +	if (sensor_platforms == NULL)
> +		goto error_platforms;
> +
> +	memset(sensor_type, 0, sizeof(sensor_type));
> +	id = 0;
> +	for (i = 0; i < sensor_num; i++) {
> +		params->cmd = MOTIONSENSE_CMD_INFO;
> +		params->info.sensor_num = i;
> +		ret = cros_ec_cmd_xfer(ec->ec_dev, msg);
> +		if (ret < 0 || msg->result != EC_RES_SUCCESS) {
> +			dev_warn(ec->dev, "no info for EC sensor %d : %d/%d\n",
> +				 i, ret, msg->result);
> +			continue;
> +		}
> +		switch (resp->info.type) {
> +		case MOTIONSENSE_TYPE_ACCEL:
> +			sensor_cells[id].name = "cros-ec-accel";
> +			break;
> +		case MOTIONSENSE_TYPE_GYRO:
> +			sensor_cells[id].name = "cros-ec-gyro";
> +			break;
> +		case MOTIONSENSE_TYPE_MAG:
> +			sensor_cells[id].name = "cros-ec-mag";
> +			break;
> +		case MOTIONSENSE_TYPE_PROX:
> +			sensor_cells[id].name = "cros-ec-prox";
> +			break;
> +		case MOTIONSENSE_TYPE_LIGHT:
> +			sensor_cells[id].name = "cros-ec-light";
> +			break;
> +		case MOTIONSENSE_TYPE_ACTIVITY:
> +			sensor_cells[id].name = "cros-ec-activity";
> +			break;
> +		default:
> +			dev_warn(ec->dev, "unknown type %d\n", resp->info.type);
> +			continue;
> +		}
> +		sensor_platforms[id].sensor_num = i;
> +		sensor_cells[id].id = sensor_type[resp->info.type];
> +		sensor_cells[id].platform_data = &sensor_platforms[id];
> +		sensor_cells[id].pdata_size =
> +			sizeof(struct cros_ec_sensor_platform);
> +
> +		sensor_type[resp->info.type]++;
> +		id++;
> +	}
> +	if (sensor_type[MOTIONSENSE_TYPE_ACCEL] >= 2) {
> +		sensor_platforms[id].sensor_num = sensor_num;
> +
> +		sensor_cells[id].name = "cros-ec-angle";
> +		sensor_cells[id].id = 0;
> +		sensor_cells[id].platform_data = &sensor_platforms[id];
> +		sensor_cells[id].pdata_size =
> +			sizeof(struct cros_ec_sensor_platform);
> +		id++;
> +	}
> +	if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) {
> +		sensor_cells[id].name = "cros-ec-ring";
> +		id++;
> +	}
> +
> +	ret = mfd_add_devices(ec->dev, 0, sensor_cells, id,
> +			      NULL, 0, NULL);
> +	if (ret)
> +		dev_err(ec->dev, "failed to add EC sensors\n");
> +
> +	kfree(sensor_platforms);
> +error_platforms:
> +	kfree(sensor_cells);
> +error:
> +	kfree(msg);
> +}
> +
>  static int ec_device_probe(struct platform_device *pdev)
>  {
>  	int retval = -ENOMEM;
> @@ -319,6 +437,10 @@ static int ec_device_probe(struct platform_device *pdev)
>  		goto dev_reg_failed;
>  	}
>  
> +	/* check whether this EC is a sensor hub. */
> +	if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE))
> +		cros_ec_sensors_register(ec);
> +
>  	return 0;
>  
>  dev_reg_failed:
>