ACPI: thinkpad-acpi: add sysfs led class support to thinkpad leds (v3.2) (af116101) · Commits · e / devices / android_kernel_xiaomi_markw

Documentation/laptops/thinkpad-acpi.txt

+41 −6

Original line number	Diff line number	Diff line
		@@ -876,28 +876,63 @@ The cmos command interface is prone to firmware split-brain problems, as
		in newer ThinkPads it is just a compatibility layer. Do not use it, it is
		exported just as a debug tool.

		LED control -- /proc/acpi/ibm/led
		---------------------------------
		LED control
		-----------

		Some of the LED indicators can be controlled through this feature. The
		available commands are:
		procfs: /proc/acpi/ibm/led
		sysfs attributes: as per led class, see below for names

		Some of the LED indicators can be controlled through this feature. On
		some older ThinkPad models, it is possible to query the status of the
		LED indicators as well. Newer ThinkPads cannot query the real status
		of the LED indicators.

		procfs notes:

		The available commands are:

		echo '<led number> on' >/proc/acpi/ibm/led
		echo '<led number> off' >/proc/acpi/ibm/led
		echo '<led number> blink' >/proc/acpi/ibm/led

		The <led number> range is 0 to 7. The set of LEDs that can be
		controlled varies from model to model. Here is the mapping on the X40:
		controlled varies from model to model. Here is the common ThinkPad
		mapping:

		0 - power
		1 - battery (orange)
		2 - battery (green)
		3 - UltraBase
		3 - UltraBase/dock
		4 - UltraBay
		5 - UltraBase battery slot
		6 - (unknown)
		7 - standby

		All of the above can be turned on and off and can be made to blink.

		sysfs notes:

		The ThinkPad LED sysfs interface is described in detail by the led class
		documentation, in Documentation/leds-class.txt.

		The leds are named (in LED ID order, from 0 to 7):
		"tpacpi::power", "tpacpi:orange:batt", "tpacpi:green:batt",
		"tpacpi::dock_active", "tpacpi::bay_active", "tpacpi::dock_batt",
		"tpacpi::unknown_led", "tpacpi::standby".

		Due to limitations in the sysfs led class, if the status of the LED
		indicators cannot be read due to an error, thinkpad-acpi will report it as
		a brightness of zero (same as LED off).

		If the thinkpad firmware doesn't support reading the current status,
		trying to read the current LED brightness will just return whatever
		brightness was last written to that attribute.

		These LEDs can blink using hardware acceleration. To request that a
		ThinkPad indicator LED should blink in hardware accelerated mode, use the
		"timer" trigger, and leave the delay_on and delay_off parameters set to
		zero (to request hardware acceleration autodetection).

		ACPI sounds -- /proc/acpi/ibm/beep
		----------------------------------

drivers/misc/thinkpad_acpi.c

+135 −1

Original line number	Diff line number	Diff line
		@@ -277,6 +277,7 @@ struct tpacpi_led_classdev {
		struct led_classdev led_classdev;
		struct work_struct work;
		enum led_brightness new_brightness;
		unsigned int led;
		};

		/****************************************************************************
		@@ -3814,20 +3815,38 @@ TPACPI_HANDLE(led, ec, "SLED", /* 570 */
		"LED", /* all others */
		); /* R30, R31 */

		#define TPACPI_LED_NUMLEDS 8
		static struct tpacpi_led_classdev *tpacpi_leds;
		static enum led_status_t tpacpi_led_state_cache[TPACPI_LED_NUMLEDS];
		static const char const *tpacpi_led_names[TPACPI_LED_NUMLEDS] = {
		/* there's a limit of 19 chars + NULL before 2.6.26 */
		"tpacpi::power",
		"tpacpi:orange:batt",
		"tpacpi:green:batt",
		"tpacpi::dock_active",
		"tpacpi::bay_active",
		"tpacpi::dock_batt",
		"tpacpi::unknown_led",
		"tpacpi::standby",
		};

		static int led_get_status(unsigned int led)
		{
		int status;
		enum led_status_t led_s;

		switch (led_supported) {
		case TPACPI_LED_570:
		if (!acpi_evalf(ec_handle,
		&status, "GLED", "dd", 1 << led))
		return -EIO;
		return (status == 0)?
		led_s = (status == 0)?
		TPACPI_LED_OFF :
		((status == 1)?
		TPACPI_LED_ON :
		TPACPI_LED_BLINK);
		tpacpi_led_state_cache[led] = led_s;
		return led_s;
		default:
		return -ENXIO;
		}
		@@ -3874,11 +3893,96 @@ static int led_set_status(unsigned int led, enum led_status_t ledstatus)
		rc = -ENXIO;
		}

		if (!rc)
		tpacpi_led_state_cache[led] = ledstatus;

		return rc;
		}

		static void led_sysfs_set_status(unsigned int led,
		enum led_brightness brightness)
		{
		led_set_status(led,
		(brightness == LED_OFF) ?
		TPACPI_LED_OFF :
		(tpacpi_led_state_cache[led] == TPACPI_LED_BLINK) ?
		TPACPI_LED_BLINK : TPACPI_LED_ON);
		}

		static void led_set_status_worker(struct work_struct *work)
		{
		struct tpacpi_led_classdev *data =
		container_of(work, struct tpacpi_led_classdev, work);

		if (likely(tpacpi_lifecycle == TPACPI_LIFE_RUNNING))
		led_sysfs_set_status(data->led, data->new_brightness);
		}

		static void led_sysfs_set(struct led_classdev *led_cdev,
		enum led_brightness brightness)
		{
		struct tpacpi_led_classdev *data = container_of(led_cdev,
		struct tpacpi_led_classdev, led_classdev);

		data->new_brightness = brightness;
		schedule_work(&data->work);
		}

		static int led_sysfs_blink_set(struct led_classdev *led_cdev,
		unsigned long delay_on, unsigned long delay_off)
		{
		struct tpacpi_led_classdev *data = container_of(led_cdev,
		struct tpacpi_led_classdev, led_classdev);

		/* Can we choose the flash rate? */
		if (delay_on == 0 && delay_off == 0) {
		/* yes. set them to the hardware blink rate (1 Hz) */
		delay_on = 500; / ms */
		delay_off = 500; / ms */
		} else if ((delay_on != 500) \|\| (delay_off != 500))
		return -EINVAL;

		data->new_brightness = TPACPI_LED_BLINK;
		schedule_work(&data->work);

		return 0;
		}

		static enum led_brightness led_sysfs_get(struct led_classdev *led_cdev)
		{
		int rc;

		struct tpacpi_led_classdev *data = container_of(led_cdev,
		struct tpacpi_led_classdev, led_classdev);

		rc = led_get_status(data->led);

		if (rc == TPACPI_LED_OFF \|\| rc < 0)
		rc = LED_OFF; /* no error handling in led class :( */
		else
		rc = LED_FULL;

		return rc;
		}

		static void led_exit(void)
		{
		unsigned int i;

		for (i = 0; i < TPACPI_LED_NUMLEDS; i++) {
		if (tpacpi_leds[i].led_classdev.name)
		led_classdev_unregister(&tpacpi_leds[i].led_classdev);
		}

		kfree(tpacpi_leds);
		tpacpi_leds = NULL;
		}

		static int __init led_init(struct ibm_init_struct *iibm)
		{
		unsigned int i;
		int rc;

		vdbg_printk(TPACPI_DBG_INIT, "initializing LED subdriver\n");

		TPACPI_ACPIHANDLE_INIT(led);
		@@ -3899,6 +4003,35 @@ static int __init led_init(struct ibm_init_struct *iibm)
		vdbg_printk(TPACPI_DBG_INIT, "LED commands are %s, mode %d\n",
		str_supported(led_supported), led_supported);

		tpacpi_leds = kzalloc(sizeof(tpacpi_leds) TPACPI_LED_NUMLEDS,
		GFP_KERNEL);
		if (!tpacpi_leds) {
		printk(TPACPI_ERR "Out of memory for LED data\n");
		return -ENOMEM;
		}

		for (i = 0; i < TPACPI_LED_NUMLEDS; i++) {
		tpacpi_leds[i].led = i;

		tpacpi_leds[i].led_classdev.brightness_set = &led_sysfs_set;
		tpacpi_leds[i].led_classdev.blink_set = &led_sysfs_blink_set;
		if (led_supported == TPACPI_LED_570)
		tpacpi_leds[i].led_classdev.brightness_get =
		&led_sysfs_get;

		tpacpi_leds[i].led_classdev.name = tpacpi_led_names[i];

		INIT_WORK(&tpacpi_leds[i].work, led_set_status_worker);

		rc = led_classdev_register(&tpacpi_pdev->dev,
		&tpacpi_leds[i].led_classdev);
		if (rc < 0) {
		tpacpi_leds[i].led_classdev.name = NULL;
		led_exit();
		return rc;
		}
		}

		return (led_supported != TPACPI_LED_NONE)? 0 : 1;
		}

		@@ -3969,6 +4102,7 @@ static struct ibm_struct led_driver_data = {
		.name = "led",
		.read = led_read,
		.write = led_write,
		.exit = led_exit,
		};

		/*************************************************************************