From 0a3db1cec5d476804185114ff5d1845aed3936b3 Mon Sep 17 00:00:00 2001 From: Zhao Yakui Date: Mon, 2 Feb 2009 11:33:41 +0800 Subject: [PATCH] ACPI: Skip the first two elements in the _BCL package According to the Spec the first two elements in the _BCL package won't be regarded as the available brightness level. The first is the brightness when full power is connected to the box(It means that the AC adapter is plugged). The second is the brightness level when the box is on battery. If the first two elements are still used while finding the next brightness level, it will fall back to the lowest level when keeping on pressing hotkey. (On some boxes the brightness will be changed twice when hotkey is pressed once. One is in the ACPI video driver. The other is changed by sys I/F. In the ACPI video driver the first two elements will be used while changing the brightness. But the first two elements is skipped while using sys I/F. In such case there exists the inconsistency). So he first two elements had better be skipped while showing the available brightness or finding the next brightness level. http://bugzilla.kernel.org/show_bug.cgi?id=12450 Signed-off-by: Zhao Yakui Signed-off-by: Len Brown --- drivers/acpi/video.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c index f261737636da..c9bfca0d8677 100644 --- a/drivers/acpi/video.c +++ b/drivers/acpi/video.c @@ -1020,7 +1020,7 @@ acpi_video_device_brightness_seq_show(struct seq_file *seq, void *offset) } seq_printf(seq, "levels: "); - for (i = 0; i < dev->brightness->count; i++) + for (i = 2; i < dev->brightness->count; i++) seq_printf(seq, " %d", dev->brightness->levels[i]); seq_printf(seq, "\ncurrent: %d\n", dev->brightness->curr); @@ -1059,7 +1059,7 @@ acpi_video_device_write_brightness(struct file *file, return -EFAULT; /* validate through the list of available levels */ - for (i = 0; i < dev->brightness->count; i++) + for (i = 2; i < dev->brightness->count; i++) if (level == dev->brightness->levels[i]) { if (ACPI_SUCCESS (acpi_video_device_lcd_set_level(dev, level))) @@ -1712,7 +1712,7 @@ acpi_video_get_next_level(struct acpi_video_device *device, max = max_below = 0; min = min_above = 255; /* Find closest level to level_current */ - for (i = 0; i < device->brightness->count; i++) { + for (i = 2; i < device->brightness->count; i++) { l = device->brightness->levels[i]; if (abs(l - level_current) < abs(delta)) { delta = l - level_current; @@ -1722,7 +1722,7 @@ acpi_video_get_next_level(struct acpi_video_device *device, } /* Ajust level_current to closest available level */ level_current += delta; - for (i = 0; i < device->brightness->count; i++) { + for (i = 2; i < device->brightness->count; i++) { l = device->brightness->levels[i]; if (l < min) min = l; -- 2.39.5