Commit a16b2e28 authored by Gwendal Grignou's avatar Gwendal Grignou Committed by Enric Balletbo i Serra
Browse files

mfd / platform: cros_ec: Add sensor_count and make check_features public 



Add a new function to return the number of MEMS sensors available in a
ChromeOS Embedded Controller. It uses MOTIONSENSE_CMD_DUMP if available
or a specific memory map ACPI registers to find out.

Also, make check_features public as it can be useful for other drivers
to know what the Embedded Controller supports.

Signed-off-by: default avatarGwendal Grignou <gwendal@chromium.org>
Acked-by: default avatarLee Jones <lee.jones@linaro.org>
Signed-off-by: default avatarEnric Balletbo i Serra <enric.balletbo@collabora.com>
parent c9b46568

drivers/mfd/cros_ec_dev.c

+0 −32
Original line number Diff line number Diff line
@@ -112,38 +112,6 @@ static const struct mfd_cell cros_ec_vbc_cells[] = { 
	{ .name = "cros-ec-vbc", }

};



static int cros_ec_check_features(struct cros_ec_dev *ec, int feature)

{

	struct cros_ec_command *msg;

	int ret;



	if (ec->features[0] == -1U && ec->features[1] == -1U) {

		/* features bitmap not read yet */

		msg = kzalloc(sizeof(*msg) + sizeof(ec->features), GFP_KERNEL);

		if (!msg)

			return -ENOMEM;



		msg->command = EC_CMD_GET_FEATURES + ec->cmd_offset;

		msg->insize = sizeof(ec->features);



		ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);

		if (ret < 0) {

			dev_warn(ec->dev, "cannot get EC features: %d/%d\n",

				 ret, msg->result);

			memset(ec->features, 0, sizeof(ec->features));

		} else {

			memcpy(ec->features, msg->data, sizeof(ec->features));

		}



		dev_dbg(ec->dev, "EC features %08x %08x\n",

			ec->features[0], ec->features[1]);



		kfree(msg);

	}



	return ec->features[feature / 32] & EC_FEATURE_MASK_0(feature);

}



static void cros_ec_class_release(struct device *dev)

{

	kfree(to_cros_ec_dev(dev));

drivers/platform/chrome/cros_ec_proto.c

+117 −0
Original line number Diff line number Diff line
@@ -717,3 +717,120 @@ u32 cros_ec_get_host_event(struct cros_ec_device *ec_dev) 
	return host_event;

}

EXPORT_SYMBOL(cros_ec_get_host_event);



/**

 * cros_ec_check_features() - Test for the presence of EC features

 *

 * @ec: EC device, does not have to be connected directly to the AP,

 *      can be daisy chained through another device.

 * @feature: One of ec_feature_code bit.

 *

 * Call this function to test whether the ChromeOS EC supports a feature.

 *

 * Return: 1 if supported, 0 if not

 */

int cros_ec_check_features(struct cros_ec_dev *ec, int feature)

{

	struct cros_ec_command *msg;

	int ret;



	if (ec->features[0] == -1U && ec->features[1] == -1U) {

		/* features bitmap not read yet */

		msg = kzalloc(sizeof(*msg) + sizeof(ec->features), GFP_KERNEL);

		if (!msg)

			return -ENOMEM;



		msg->command = EC_CMD_GET_FEATURES + ec->cmd_offset;

		msg->insize = sizeof(ec->features);



		ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);

		if (ret < 0) {

			dev_warn(ec->dev, "cannot get EC features: %d/%d\n",

				 ret, msg->result);

			memset(ec->features, 0, sizeof(ec->features));

		} else {

			memcpy(ec->features, msg->data, sizeof(ec->features));

		}



		dev_dbg(ec->dev, "EC features %08x %08x\n",

			ec->features[0], ec->features[1]);



		kfree(msg);

	}



	return ec->features[feature / 32] & EC_FEATURE_MASK_0(feature);

}

EXPORT_SYMBOL_GPL(cros_ec_check_features);



/**

 * cros_ec_get_sensor_count() - Return the number of MEMS sensors supported.

 *

 * @ec: EC device, does not have to be connected directly to the AP,

 *      can be daisy chained through another device.

 * Return: < 0 in case of error.

 */

int cros_ec_get_sensor_count(struct cros_ec_dev *ec)

{

	/*

	 * Issue a command to get the number of sensor reported.

	 * If not supported, check for legacy mode.

	 */

	int ret, sensor_count;

	struct ec_params_motion_sense *params;

	struct ec_response_motion_sense *resp;

	struct cros_ec_command *msg;

	struct cros_ec_device *ec_dev = ec->ec_dev;

	u8 status;



	msg = kzalloc(sizeof(*msg) + max(sizeof(*params), sizeof(*resp)),

		      GFP_KERNEL);

	if (!msg)

		return -ENOMEM;



	msg->version = 1;

	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) {

		sensor_count = ret;

	} else if (msg->result != EC_RES_SUCCESS) {

		sensor_count = -EPROTO;

	} else {

		resp = (struct ec_response_motion_sense *)msg->data;

		sensor_count = resp->dump.sensor_count;

	}

	kfree(msg);



	/*

	 * Check legacy mode: Let's find out if sensors are accessible

	 * via LPC interface.

	 */

	if (sensor_count == -EPROTO &&

	    ec->cmd_offset == 0 &&

	    ec_dev->cmd_readmem) {

		ret = ec_dev->cmd_readmem(ec_dev, EC_MEMMAP_ACC_STATUS,

				1, &status);

		if (ret >= 0 &&

		    (status & EC_MEMMAP_ACC_STATUS_PRESENCE_BIT)) {

			/*

			 * We have 2 sensors, one in the lid, one in the base.

			 */

			sensor_count = 2;

		} else {

			/*

			 * EC uses LPC interface and no sensors are presented.

			 */

			sensor_count = 0;

		}

	} else if (sensor_count == -EPROTO) {

		/* EC responded, but does not understand DUMP command. */

		sensor_count = 0;

	}

	return sensor_count;

}

EXPORT_SYMBOL_GPL(cros_ec_get_sensor_count);

include/linux/platform_data/cros_ec_proto.h

+5 −0
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ 
#include <linux/mutex.h>

#include <linux/notifier.h>



#include <linux/mfd/cros_ec.h>

#include <linux/platform_data/cros_ec_commands.h>



#define CROS_EC_DEV_NAME	"cros_ec"
@@ -213,4 +214,8 @@ int cros_ec_get_next_event(struct cros_ec_device *ec_dev, bool *wake_event); 


u32 cros_ec_get_host_event(struct cros_ec_device *ec_dev);



int cros_ec_check_features(struct cros_ec_dev *ec, int feature);



int cros_ec_get_sensor_count(struct cros_ec_dev *ec);



#endif /* __LINUX_CROS_EC_PROTO_H */

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