OMAP: LCD LS037V7DW01: Add Backlight driver support

Tested on OMAP3EVM for OMAP3530 and AM/DM 3730.

Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com>
[tomi.valkeinen@nokia.com: added slab.h include]
[tomi.valkeinen@nokia.com: added dependency to BACKLIGHT_CLASS_DEVICE]
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@nokia.com>

2 files changed, 79 insertions, 0 deletions

diff --git a/drivers/video/omap2/displays/Kconfig b/drivers/video/omap2/displays/Kconfig
index dfb57ee50861..ea8ccd362c22 100644
--- a/drivers/video/omap2/displays/Kconfig
+++ b/drivers/video/omap2/displays/Kconfig
@@ -10,6 +10,7 @@ config PANEL_GENERIC
 config PANEL_SHARP_LS037V7DW01
         tristate "Sharp LS037V7DW01 LCD Panel"
         depends on OMAP2_DSS
+        select BACKLIGHT_CLASS_DEVICE
         help
           LCD Panel used in TI's SDP3430 and EVM boards
 
diff --git a/drivers/video/omap2/displays/panel-sharp-ls037v7dw01.c b/drivers/video/omap2/displays/panel-sharp-ls037v7dw01.c
index 8d51a5e6341c..7d9eb2b1f5af 100644
--- a/drivers/video/omap2/displays/panel-sharp-ls037v7dw01.c
+++ b/drivers/video/omap2/displays/panel-sharp-ls037v7dw01.c
@@ -20,10 +20,17 @@
 #include <linux/module.h>
 #include <linux/delay.h>
 #include <linux/device.h>
+#include <linux/backlight.h>
+#include <linux/fb.h>
 #include <linux/err.h>
+#include <linux/slab.h>
 
 #include <plat/display.h>
 
+struct sharp_data {
+        struct backlight_device *bl;
+};
+
 static struct omap_video_timings sharp_ls_timings = {
         .x_res = 480,
         .y_res = 640,
@@ -39,18 +46,89 @@ static struct omap_video_timings sharp_ls_timings = {
         .vbp            = 1,
 };
 
+static int sharp_ls_bl_update_status(struct backlight_device *bl)
+{
+        struct omap_dss_device *dssdev = dev_get_drvdata(&bl->dev);
+        int level;
+
+        if (!dssdev->set_backlight)
+                return -EINVAL;
+
+        if (bl->props.fb_blank == FB_BLANK_UNBLANK &&
+                        bl->props.power == FB_BLANK_UNBLANK)
+                level = bl->props.brightness;
+        else
+                level = 0;
+
+        return dssdev->set_backlight(dssdev, level);
+}
+
+static int sharp_ls_bl_get_brightness(struct backlight_device *bl)
+{
+        if (bl->props.fb_blank == FB_BLANK_UNBLANK &&
+                        bl->props.power == FB_BLANK_UNBLANK)
+                return bl->props.brightness;
+
+        return 0;
+}
+
+static const struct backlight_ops sharp_ls_bl_ops = {
+        .get_brightness = sharp_ls_bl_get_brightness,
+        .update_status  = sharp_ls_bl_update_status,
+};
+
+
+
 static int sharp_ls_panel_probe(struct omap_dss_device *dssdev)
 {
+        struct backlight_properties props;
+        struct backlight_device *bl;
+        struct sharp_data *sd;
+        int r;
+
         dssdev->panel.config = OMAP_DSS_LCD_TFT | OMAP_DSS_LCD_IVS |
                 OMAP_DSS_LCD_IHS;
         dssdev->panel.acb = 0x28;
         dssdev->panel.timings = sharp_ls_timings;
 
+        sd = kzalloc(sizeof(*sd), GFP_KERNEL);
+        if (!sd)
+                return -ENOMEM;
+
+        dev_set_drvdata(&dssdev->dev, sd);
+
+        memset(&props, 0, sizeof(struct backlight_properties));
+        props.max_brightness = dssdev->max_backlight_level;
+
+        bl = backlight_device_register("sharp-ls", &dssdev->dev, dssdev,
+                        &sharp_ls_bl_ops, &props);
+        if (IS_ERR(bl)) {
+                r = PTR_ERR(bl);
+                kfree(sd);
+                return r;
+        }
+        sd->bl = bl;
+
+        bl->props.fb_blank = FB_BLANK_UNBLANK;
+        bl->props.power = FB_BLANK_UNBLANK;
+        bl->props.brightness = dssdev->max_backlight_level;
+        r = sharp_ls_bl_update_status(bl);
+        if (r < 0)
+                dev_err(&dssdev->dev, "failed to set lcd brightness\n");
+
         return 0;
 }
 
 static void sharp_ls_panel_remove(struct omap_dss_device *dssdev)
 {
+        struct sharp_data *sd = dev_get_drvdata(&dssdev->dev);
+        struct backlight_device *bl = sd->bl;
+
+        bl->props.power = FB_BLANK_POWERDOWN;
+        sharp_ls_bl_update_status(bl);
+        backlight_device_unregister(bl);
+
+        kfree(sd);
 }
 
 static int sharp_ls_power_on(struct omap_dss_device *dssdev)