drivers/video/backlight/platform_lcd.c: introduce probe callback

Platform LCD devices may need to do some device-specific initialization
before they can be used (regulator or GPIO setup, for example), but
currently the driver does not support any way of doing this.  This patch
adds a probe() callback to plat_lcd_data which platform LCD devices can
set to indicate that device-specific initialization is needed.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 7 insertions, 0 deletions

diff --git a/drivers/video/backlight/platform_lcd.c b/drivers/video/backlight/platform_lcd.c
index 54d94de652b0..056836706708 100644
--- a/drivers/video/backlight/platform_lcd.c
+++ b/drivers/video/backlight/platform_lcd.c
@@ -86,6 +86,12 @@ static int platform_lcd_probe(struct platform_device *pdev)
                 return -EINVAL;
         }
 
+        if (pdata->probe) {
+                err = pdata->probe(pdata);
+                if (err)
+                        return err;
+        }
+
         plcd = devm_kzalloc(&pdev->dev, sizeof(struct platform_lcd),
                             GFP_KERNEL);
         if (!plcd) {
diff --git a/include/video/platform_lcd.h b/include/video/platform_lcd.h
index ad3bdfe743b2..23864b284147 100644
--- a/include/video/platform_lcd.h
+++ b/include/video/platform_lcd.h
@@ -15,6 +15,7 @@ struct plat_lcd_data;
 struct fb_info;
 
 struct plat_lcd_data {
+        int     (*probe)(struct plat_lcd_data *);
         void    (*set_power)(struct plat_lcd_data *, unsigned int power);
         int     (*match_fb)(struct plat_lcd_data *, struct fb_info *);
 };