ACPI video: support _BQC/_BCL/_BCM methods that use index values (1a7c618a) · Commits · 戴 / test

drivers/acpi/video.c

+70 −21

Original line number	Diff line number	Diff line
		@@ -171,6 +171,9 @@ struct acpi_video_device_cap {
		struct acpi_video_brightness_flags {
		u8 _BCL_no_ac_battery_levels:1; /* no AC/Battery levels in _BCL */
		u8 _BCL_reversed:1; /* _BCL package is in a reversed order*/
		u8 _BCL_use_index:1; /* levels in _BCL are index values */
		u8 _BCM_use_index:1; /* input of _BCM is an index value */
		u8 _BQC_use_index:1; /* _BQC returns an index value */
		};

		struct acpi_video_device_brightness {
		@@ -505,6 +508,7 @@ acpi_video_device_lcd_set_level(struct acpi_video_device *device, int level)
		device->brightness->curr = level;
		for (state = 2; state < device->brightness->count; state++)
		if (level == device->brightness->levels[state]) {
		if (device->backlight)
		device->backlight->props.brightness = state - 2;
		return 0;
		}
		@@ -523,6 +527,13 @@ acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
		status = acpi_evaluate_integer(device->dev->handle, "_BQC",
		NULL, level);
		if (ACPI_SUCCESS(status)) {
		if (device->brightness->flags._BQC_use_index) {
		if (device->brightness->flags._BCL_reversed)
		*level = device->brightness->count
		- 3 - (*level);
		level = device->brightness->levels[level + 2];

		}
		device->brightness->curr = *level;
		return 0;
		} else {
		@@ -689,8 +700,10 @@ acpi_video_init_brightness(struct acpi_video_device *device)
		{
		union acpi_object *obj = NULL;
		int i, max_level = 0, count = 0, level_ac_battery = 0;
		unsigned long long level, level_old;
		union acpi_object *o;
		struct acpi_video_device_brightness *br = NULL;
		int result = -EINVAL;

		if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device, &obj))) {
		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
		@@ -704,13 +717,16 @@ acpi_video_init_brightness(struct acpi_video_device *device)
		br = kzalloc(sizeof(*br), GFP_KERNEL);
		if (!br) {
		printk(KERN_ERR "can't allocate memory\n");
		result = -ENOMEM;
		goto out;
		}

		br->levels = kmalloc((obj->package.count + 2) * sizeof *(br->levels),
		GFP_KERNEL);
		if (!br->levels)
		if (!br->levels) {
		result = -ENOMEM;
		goto out_free;
		}

		for (i = 0; i < obj->package.count; i++) {
		o = (union acpi_object *)&obj->package.elements[i];
		@@ -756,10 +772,55 @@ acpi_video_init_brightness(struct acpi_video_device *device)

		br->count = count;
		device->brightness = br;

		/* Check the input/output of _BQC/_BCL/_BCM */
		if ((max_level < 100) && (max_level <= (count - 2)))
		br->flags._BCL_use_index = 1;

		/*
		* _BCM is always consistent with _BCL,
		* at least for all the laptops we have ever seen.
		*/
		br->flags._BCM_use_index = br->flags._BCL_use_index;

		/* _BQC uses INDEX while _BCL uses VALUE in some laptops */
		br->curr = max_level;
		result = acpi_video_device_lcd_get_level_current(device, &level_old);
		if (result)
		goto out_free_levels;

		result = acpi_video_device_lcd_set_level(device, br->curr);
		if (result)
		goto out_free_levels;

		result = acpi_video_device_lcd_get_level_current(device, &level);
		if (result)
		goto out_free_levels;

		if ((level != level_old) && !br->flags._BCM_use_index) {
		/* Note:
		* This piece of code does not work correctly if the current
		* brightness levels is 0.
		* But I guess boxes that boot with such a dark screen are rare
		* and no more code is needed to cover this specifial case.
		*/

		if (level_ac_battery != 2) {
		/*
		* For now, we don't support the _BCL like this:
		* 16, 15, 0, 1, 2, 3, ..., 14, 15, 16
		* because we may mess up the index returned by _BQC.
		* Plus: we have not got a box like this.
		*/
		ACPI_ERROR((AE_INFO, "_BCL not supported\n"));
		}
		br->flags._BQC_use_index = 1;
		}

		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
		"found %d brightness levels\n", count - 2));
		kfree(obj);
		return max_level;
		return result;

		out_free_levels:
		kfree(br->levels);
		@@ -768,7 +829,7 @@ out_free:
		out:
		device->brightness = NULL;
		kfree(obj);
		return 0;
		return result;
		}

		/*
		@@ -785,7 +846,6 @@ out:
		static void acpi_video_device_find_cap(struct acpi_video_device *device)
		{
		acpi_handle h_dummy1;
		u32 max_level = 0;


		memset(&device->cap, 0, sizeof(device->cap));
		@@ -814,13 +874,14 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device)
		device->cap._DSS = 1;
		}

		if (acpi_video_backlight_support())
		max_level = acpi_video_init_brightness(device);

		if (device->cap._BCL && device->cap._BCM && max_level > 0) {
		if (acpi_video_backlight_support()) {
		int result;
		static int count = 0;
		char *name;

		result = acpi_video_init_brightness(device);
		if (result)
		return;
		name = kzalloc(MAX_NAME_LEN, GFP_KERNEL);
		if (!name)
		return;
		@@ -829,18 +890,6 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device)
		device->backlight = backlight_device_register(name,
		NULL, device, &acpi_backlight_ops);
		device->backlight->props.max_brightness = device->brightness->count-3;
		/*
		* If there exists the _BQC object, the _BQC object will be
		* called to get the current backlight brightness. Otherwise
		* the brightness will be set to the maximum.
		*/
		if (device->cap._BQC)
		device->backlight->props.brightness =
		acpi_video_get_brightness(device->backlight);
		else
		device->backlight->props.brightness =
		device->backlight->props.max_brightness;
		backlight_update_status(device->backlight);
		kfree(name);

		device->cdev = thermal_cooling_device_register("LCD",

Admin message