Commit 2d8251d9 authored by Gwendal Grignou's avatar Gwendal Grignou Committed by Tzung-Bi Shih
Browse files

platform/chrome: lightbar: Report number of segments 



Add attribue `num_segments` to return the number of exposed LED segments
in the lightbar. It can be smaller than the number of physical leds in
the lightbar.

Test: Check the attribute is present and returns a value when read.

Signed-off-by: default avatarGwendal Grignou <gwendal@google.com>
Link: https://lore.kernel.org/r/20260130081351.487517-1-gwendal@google.com


Signed-off-by: default avatarTzung-Bi Shih <tzungbi@kernel.org>
parent ec0dd36d

drivers/platform/chrome/cros_ec_lightbar.c

+43 −0
Original line number Diff line number Diff line
@@ -180,6 +180,47 @@ static ssize_t version_show(struct device *dev, 
	return sysfs_emit(buf, "%d %d\n", version, flags);

}



static ssize_t num_segments_show(struct device *dev,

				 struct device_attribute *attr, char *buf)

{

	struct ec_params_lightbar *param;

	struct ec_response_lightbar *resp;

	struct cros_ec_command *msg;

	struct cros_ec_dev *ec = to_cros_ec_dev(dev);

	uint32_t num = 0;

	int ret;



	ret = lb_throttle();

	if (ret)

		return ret;



	msg = alloc_lightbar_cmd_msg(ec);

	if (!msg)

		return -ENOMEM;



	param = (struct ec_params_lightbar *)msg->data;

	param->cmd = LIGHTBAR_CMD_GET_PARAMS_V3;

	msg->outsize = sizeof(param->cmd);

	msg->insize = sizeof(resp->get_params_v3);

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

	if (ret < 0 && ret != -EINVAL)

		goto exit;



	if (msg->result == EC_RES_SUCCESS) {

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

		num = resp->get_params_v3.reported_led_num;

	}



	/*

	 * Anything else (ie, EC_RES_INVALID_COMMAND) - no direct control over

	 * LEDs, return that no leds are supported.

	 */

	ret = sysfs_emit(buf, "%u\n", num);

exit:

	kfree(msg);

	return ret;

}



static ssize_t brightness_store(struct device *dev,

				struct device_attribute *attr,

				const char *buf, size_t count)
@@ -512,6 +553,7 @@ static ssize_t userspace_control_store(struct device *dev, 
/* Module initialization */



static DEVICE_ATTR_RW(interval_msec);

static DEVICE_ATTR_RO(num_segments);

static DEVICE_ATTR_RO(version);

static DEVICE_ATTR_WO(brightness);

static DEVICE_ATTR_WO(led_rgb);
@@ -521,6 +563,7 @@ static DEVICE_ATTR_RW(userspace_control); 


static struct attribute *__lb_cmds_attrs[] = {

	&dev_attr_interval_msec.attr,

	&dev_attr_num_segments.attr,

	&dev_attr_version.attr,

	&dev_attr_brightness.attr,

	&dev_attr_led_rgb.attr,

include/linux/platform_data/cros_ec_commands.h

+11 −0
Original line number Diff line number Diff line
@@ -2005,6 +2005,14 @@ struct lightbar_params_v2_colors { 
	struct rgb_s color[8];			/* 0-3 are Google colors */

} __ec_todo_packed;



struct lightbar_params_v3 {

	/*

	 *  Number of LEDs reported by the EC.

	 *  May be less than the actual number of LEDs in the lightbar.

	 */

	uint8_t reported_led_num;

} __ec_todo_packed;



/* Lightbar program. */

#define EC_LB_PROG_LEN 192

struct lightbar_program {
@@ -2086,6 +2094,8 @@ struct ec_response_lightbar { 
		struct lightbar_params_v2_thresholds get_params_v2_thlds;

		struct lightbar_params_v2_colors get_params_v2_colors;



		struct lightbar_params_v3 get_params_v3;



		struct __ec_todo_unpacked {

			uint32_t num;

			uint32_t flags;
@@ -2143,6 +2153,7 @@ enum lightbar_command { 
	LIGHTBAR_CMD_SET_PARAMS_V2_THRESHOLDS = 31,

	LIGHTBAR_CMD_GET_PARAMS_V2_COLORS = 32,

	LIGHTBAR_CMD_SET_PARAMS_V2_COLORS = 33,

	LIGHTBAR_CMD_GET_PARAMS_V3 = 34,

	LIGHTBAR_NUM_CMDS

};