From: Thomas Tuttle <linux-kernel@xxxxxxxxxxx> acpi_video_get_next_level was supposed to implement an algorithm to select a new brightness level based on the old brightness level of an ACPI video device, but it simply says "/* Fix me */" and returns the current brightness. This patch implements acpi_video_get_next_level properly. It had to change a few constants at the top of the file because they were (apparently) wrong, but it appears to work on my Dell Inspiron e1405 (with BIOS A05 only--BIOS A04 doesn't seem to send ACPI video hotkey events). [akpm@xxxxxxxx: cleanups] Cc: Len Brown <len.brown@xxxxxxxxx> Signed-off-by: Thomas Tuttle <linux-kernel@xxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxx> --- drivers/acpi/video.c | 41 ++++++++++++++++++++++++++++++++++------- 1 file changed, 34 insertions(+), 7 deletions(-) diff -puN drivers/acpi/video.c~implementation-of-acpi_video_get_next_level drivers/acpi/video.c --- a/drivers/acpi/video.c~implementation-of-acpi_video_get_next_level +++ a/drivers/acpi/video.c @@ -3,6 +3,7 @@ * * Copyright (C) 2004 Luming Yu <luming.yu@xxxxxxxxx> * Copyright (C) 2004 Bruno Ducrot <ducrot@xxxxxxxxxxxx> + * Copyright (C) 2006 Thomas Tuttle <linux-kernel@xxxxxxxxxxx> * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * @@ -47,11 +48,11 @@ #define ACPI_VIDEO_NOTIFY_NEXT_OUTPUT 0x83 #define ACPI_VIDEO_NOTIFY_PREV_OUTPUT 0x84 -#define ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS 0x82 -#define ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS 0x83 -#define ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS 0x84 -#define ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS 0x85 -#define ACPI_VIDEO_NOTIFY_DISPLAY_OFF 0x86 +#define ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS 0x85 +#define ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS 0x86 +#define ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS 0x87 +#define ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS 0x88 +#define ACPI_VIDEO_NOTIFY_DISPLAY_OFF 0x89 #define ACPI_VIDEO_HEAD_INVALID (~0u - 1) #define ACPI_VIDEO_HEAD_END (~0u) @@ -1502,8 +1503,34 @@ static int acpi_video_get_next_level(struct acpi_video_device *device, u32 level_current, u32 event) { - /*Fix me */ - return level_current; + int min, max, min_above, max_below, i, l; + max = max_below = 0; + min = min_above = 255; + for (i = 0; i < device->brightness->count; i++) { + l = device->brightness->levels[i]; + if (l < min) + min = l; + if (l > max) + max = l; + if (l < min_above && l > level_current) + min_above = l; + if (l > max_below && l < level_current) + max_below = l; + } + + switch (event) { + case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS: + return (level_current < max) ? min_above : min; + case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS: + return (level_current < max) ? min_above : max; + case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS: + return (level_current > min) ? max_below : min; + case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS: + case ACPI_VIDEO_NOTIFY_DISPLAY_OFF: + return 0; + default: + return level_current; + } } static void _ - To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html