Commit ecc2ca47 authored by Gwendal Grignou's avatar Gwendal Grignou Committed by Lee Jones
Browse files

mfd: cros_ec_dev: Register cros_ec_accel_legacy driver as a subdevice 



With this patch, the cros_ec_ctl driver will register the legacy
accelerometer driver (named cros_ec_accel_legacy) if it fails to
register sensors through the usual path cros_ec_sensors_register().
This legacy device is present on Chromebook devices with older EC
firmware only supporting deprecated EC commands:
- Glimmer based devices [Intel SOC using LPC transport]
- Veyron minnie devices [ARM SOC using SPI transport]

Tested-by: default avatarGwendal Grignou <gwendal@chromium.org>
Signed-off-by: default avatarEnric Balletbo i Serra <enric.balletbo@collabora.com>
Reviewed-by: default avatarAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: default avatarGwendal Grignou <gwendal@chromium.org>
Signed-off-by: default avatarLee Jones <lee.jones@linaro.org>
parent ac195d94

drivers/mfd/cros_ec_dev.c

+69 −0
Original line number Diff line number Diff line
@@ -383,6 +383,72 @@ error: 
	kfree(msg);

}



static struct cros_ec_sensor_platform sensor_platforms[] = {

	{ .sensor_num = 0 },

	{ .sensor_num = 1 }

};



static const struct mfd_cell cros_ec_accel_legacy_cells[] = {

	{

		.name = "cros-ec-accel-legacy",

		.platform_data = &sensor_platforms[0],

		.pdata_size = sizeof(struct cros_ec_sensor_platform),

	},

	{

		.name = "cros-ec-accel-legacy",

		.platform_data = &sensor_platforms[1],

		.pdata_size = sizeof(struct cros_ec_sensor_platform),

	}

};



static void cros_ec_accel_legacy_register(struct cros_ec_dev *ec)

{

	struct cros_ec_device *ec_dev = ec->ec_dev;

	u8 status;

	int ret;



	/*

	 * ECs that need legacy support are the main EC, directly connected to

	 * the AP.

	 */

	if (ec->cmd_offset != 0)

		return;



	/*

	 * Check if EC supports direct memory reads and if EC has

	 * accelerometers.

	 */

	if (ec_dev->cmd_readmem) {

		ret = ec_dev->cmd_readmem(ec_dev, EC_MEMMAP_ACC_STATUS, 1,

					  &status);

		if (ret < 0) {

			dev_warn(ec->dev, "EC direct read error.\n");

			return;

		}



		/* Check if EC has accelerometers. */

		if (!(status & EC_MEMMAP_ACC_STATUS_PRESENCE_BIT)) {

			dev_info(ec->dev, "EC does not have accelerometers.\n");

			return;

		}

	}



	/*

	 * The device may still support accelerometers:

	 * it would be an older ARM based device that do not suppor the

	 * EC_CMD_GET_FEATURES command.

	 *

	 * Register 2 accelerometers, we will fail in the IIO driver if there

	 * are no sensors.

	 */

	ret = mfd_add_devices(ec->dev, PLATFORM_DEVID_AUTO,

			      cros_ec_accel_legacy_cells,

			      ARRAY_SIZE(cros_ec_accel_legacy_cells),

			      NULL, 0, NULL);

	if (ret)

		dev_err(ec_dev->dev, "failed to add EC sensors\n");

}



static const struct mfd_cell cros_ec_cec_cells[] = {

	{ .name = "cros-ec-cec" }

};
@@ -488,6 +554,9 @@ static int ec_device_probe(struct platform_device *pdev) 
	/* check whether this EC is a sensor hub. */

	if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE))

		cros_ec_sensors_register(ec);

	else

		/* Workaroud for older EC firmware */

		cros_ec_accel_legacy_register(ec);



	/* Check whether this EC instance has CEC host command support */

	if (cros_ec_check_features(ec, EC_FEATURE_CEC)) {

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