drivers/video/backlight/aat2870_bl.c: fix setting max_current

 - Current implementation tests wrong value for setting
   aat2870_bl->max_current.

 - In the current implementation, we cannot differentiate between 2 cases:

   a) if pdata->max_current is not set , or

   b) pdata->max_current is set to AAT2870_CURRENT_0_45 (which is also 0).

   Fix it by setting AAT2870_CURRENT_0_45 to be 1 and adjust the equation in
   aat2870_brightness() accordingly.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Tested-by: Jin Park <jinyoungp@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/video/backlight/aat2870_bl.c b/drivers/video/backlight/aat2870_bl.c
index f13a3f7e2e8..331f1ef1dad 100644
--- a/drivers/video/backlight/aat2870_bl.c
+++ b/drivers/video/backlight/aat2870_bl.c
@@ -44,7 +44,7 @@ static inline int aat2870_brightness(struct aat2870_bl_driver_data *aat2870_bl,
         struct backlight_device *bd = aat2870_bl->bd;
         int val;
 
-        val = brightness * aat2870_bl->max_current;
+        val = brightness * (aat2870_bl->max_current - 1);
         val /= bd->props.max_brightness;
 
         return val;
@@ -175,7 +175,7 @@ static int aat2870_bl_probe(struct platform_device *pdev)
         else
                 aat2870_bl->channels = AAT2870_BL_CH_ALL;
 
-        if (pdata->max_brightness > 0)
+        if (pdata->max_current > 0)
                 aat2870_bl->max_current = pdata->max_current;
         else
                 aat2870_bl->max_current = AAT2870_CURRENT_27_9;