ACPI: VIDEO: Adjust current level to closest available one.

patch 63f0edfc0b7f8058f9d3f9b572615ec97ae011ba in mainline.

ACPI: VIDEO: Adjust current level to closest available one.

Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
Cc: Tobias Powalowski <t.powa@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index d05891f16282338d96d5cf5a5f3f22d30d6cd5c0..dad84c00ae438a491903b4a8a6f072d75d411cee 100644 (file)
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -1633,9 +1633,20 @@ static int
 acpi_video_get_next_level(struct acpi_video_device *device,
                          u32 level_current, u32 event)
 {
-       int min, max, min_above, max_below, i, l;
+       int min, max, min_above, max_below, i, l, delta = 255;
        max = max_below = 0;
        min = min_above = 255;
+       /* Find closest level to level_current */
+       for (i = 0; i < device->brightness->count; i++) {
+               l = device->brightness->levels[i];
+               if (abs(l - level_current) < abs(delta)) {
+                       delta = l - level_current;
+                       if (!delta)
+                               break;
+               }
+       }
+       /* Ajust level_current to closest available level */
+       level_current += delta;
        for (i = 0; i < device->brightness->count; i++) {
                l = device->brightness->levels[i];
                if (l < min)