Re: [PATCH 1/2] iio: common: cros_ec_sensors: determine protocol version

[Enric Balletbo i Serra <enric.balletbo@collabora.com>]

Hi,

cc'ing Doug, Gwendal and Enrico that might be interested to give a review.

This patch can be picked alone without 2/2, an is needed to have cros-ec-sensors
legacy support on ARM (see [1] and [2])

Jonathan, as [1] and [2] will go through the chrome-platform tree if you don't
mind I'd also like to carry with this patch once you're fine with it.

Thanks,
~ Enric

[1] https://patchwork.kernel.org/patch/11014329/
[2] https://patchwork.kernel.org/patch/11014327/

On 27/6/19 16:04, Fabien Lahoudere wrote:
> This patch adds a function to determine which version of the
> protocol is used to communicate with EC.
> 
> Signed-off-by: Fabien Lahoudere <fabien.lahoudere@collabora.com>
> Signed-off-by: Nick Vaccaro <nvaccaro@chromium.org>

Tested-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>

> ---
>  .../cros_ec_sensors/cros_ec_sensors_core.c    | 36 ++++++++++++++++++-
>  1 file changed, 35 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c
> index 130362ca421b..2e0f97448e64 100644
> --- a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c
> +++ b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c
> @@ -25,6 +25,31 @@ static char *cros_ec_loc[] = {
>  	[MOTIONSENSE_LOC_MAX] = "unknown",
>  };
>  
> +static int cros_ec_get_host_cmd_version_mask(struct cros_ec_device *ec_dev,
> +					     u16 cmd_offset, u16 cmd, u32 *mask)
> +{
> +	int ret;
> +	struct {
> +		struct cros_ec_command msg;
> +		union {
> +			struct ec_params_get_cmd_versions params;
> +			struct ec_response_get_cmd_versions resp;
> +		};
> +	} __packed buf = {
> +		.msg = {
> +			.command = EC_CMD_GET_CMD_VERSIONS + cmd_offset,
> +			.insize = sizeof(struct ec_response_get_cmd_versions),
> +			.outsize = sizeof(struct ec_params_get_cmd_versions)
> +			},
> +		.params = {.cmd = cmd}
> +	};
> +
> +	ret = cros_ec_cmd_xfer_status(ec_dev, &buf.msg);
> +	if (ret >= 0)
> +		*mask = buf.resp.version_mask;
> +	return ret;
> +}
> +
>  int cros_ec_sensors_core_init(struct platform_device *pdev,
>  			      struct iio_dev *indio_dev,
>  			      bool physical_device)
> @@ -33,6 +58,8 @@ int cros_ec_sensors_core_init(struct platform_device *pdev,
>  	struct cros_ec_sensors_core_state *state = iio_priv(indio_dev);
>  	struct cros_ec_dev *ec = dev_get_drvdata(pdev->dev.parent);
>  	struct cros_ec_sensor_platform *sensor_platform = dev_get_platdata(dev);
> +	u32 ver_mask;
> +	int ret;
>  
>  	platform_set_drvdata(pdev, indio_dev);
>  
> @@ -47,8 +74,15 @@ int cros_ec_sensors_core_init(struct platform_device *pdev,
>  
>  	mutex_init(&state->cmd_lock);
>  
> +	ret = cros_ec_get_host_cmd_version_mask(state->ec,
> +						ec->cmd_offset,
> +						EC_CMD_MOTION_SENSE_CMD,
> +						&ver_mask);
> +	if (ret < 0)
> +		return ret;
> +
>  	/* Set up the host command structure. */
> -	state->msg->version = 2;
> +	state->msg->version = fls(ver_mask) - 1;;
>  	state->msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
>  	state->msg->outsize = sizeof(struct ec_params_motion_sense);
>  
>