video: amba-clcd: use devm_of_find_backlight

Look up backlight device using devm_of_find_backlight().
This simplifies the code and prevents us from hardcoding
the node name in the driver.

v2:
  - Added Cc: Peter Ujfalusi

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Peter Ujfalusi <peter.ujfalusi@ti.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Douglas Anderson <dianders@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200517190139.740249-2-sam@ravnborg.org

diff --git a/drivers/video/fbdev/amba-clcd.c b/drivers/video/fbdev/amba-clcd.c
index c3d55fc..b7682de 100644 (file)
--- a/drivers/video/fbdev/amba-clcd.c
+++ b/drivers/video/fbdev/amba-clcd.c
@@ -602,20 +602,17 @@ static int clcdfb_snprintf_mode(char *buf, int size, struct fb_videomode *mode)
                        mode->refresh);
 }
 
-static int clcdfb_of_get_backlight(struct device_node *panel,
+static int clcdfb_of_get_backlight(struct device *dev,
                                   struct clcd_panel *clcd_panel)
 {
-       struct device_node *backlight;
+       struct backlight_device *backlight;
 
-       /* Look up the optional backlight phandle */
-       backlight = of_parse_phandle(panel, "backlight", 0);
-       if (backlight) {
-               clcd_panel->backlight = of_find_backlight_by_node(backlight);
-               of_node_put(backlight);
+       /* Look up the optional backlight device */
+       backlight = devm_of_find_backlight(dev);
+       if (IS_ERR(backlight))
+               return PTR_ERR(backlight);
 
-               if (!clcd_panel->backlight)
-                       return -EPROBE_DEFER;
-       }
+       clcd_panel->backlight = backlight;
        return 0;
 }
 
@@ -717,7 +714,7 @@ static int clcdfb_of_init_display(struct clcd_fb *fb)
        if (!panel)
                return -ENODEV;
 
-       err = clcdfb_of_get_backlight(panel, fb->panel);
+       err = clcdfb_of_get_backlight(&fb->dev->dev, fb->panel);
        if (err)
                return err;