mfd: max8925: Support dt for backlight

Add device tree support in max8925 backlight.

Signed-off-by: Qing Xu <qingx@marvell.com>
Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

diff --git a/drivers/video/backlight/max8925_bl.c b/drivers/video/backlight/max8925_bl.c
index 2c9bce0..5ca11b0 100644 (file)
--- a/drivers/video/backlight/max8925_bl.c
+++ b/drivers/video/backlight/max8925_bl.c
@@ -101,6 +101,29 @@ static const struct backlight_ops max8925_backlight_ops = {
        .get_brightness = max8925_backlight_get_brightness,
 };
 
+#ifdef CONFIG_OF
+static int max8925_backlight_dt_init(struct platform_device *pdev,
+                             struct max8925_backlight_pdata *pdata)
+{
+       struct device_node *nproot = pdev->dev.parent->of_node, *np;
+       int dual_string;
+
+       if (!nproot)
+               return -ENODEV;
+       np = of_find_node_by_name(nproot, "backlight");
+       if (!np) {
+               dev_err(&pdev->dev, "failed to find backlight node\n");
+               return -ENODEV;
+       }
+
+       of_property_read_u32(np, "maxim,max8925-dual-string", &dual_string);
+       pdata->dual_string = dual_string;
+       return 0;
+}
+#else
+#define max8925_backlight_dt_init(x, y)        (-1)
+#endif
+
 static int max8925_backlight_probe(struct platform_device *pdev)
 {
        struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
@@ -147,6 +170,13 @@ static int max8925_backlight_probe(struct platform_device *pdev)
        platform_set_drvdata(pdev, bl);
 
        value = 0;
+       if (pdev->dev.parent->of_node && !pdata) {
+               pdata = devm_kzalloc(&pdev->dev,
+                                    sizeof(struct max8925_backlight_pdata),
+                                    GFP_KERNEL);
+               max8925_backlight_dt_init(pdev, pdata);
+       }
+
        if (pdata) {
                if (pdata->lxw_scl)
                        value |= (1 << 7);
@@ -158,7 +188,6 @@ static int max8925_backlight_probe(struct platform_device *pdev)
        ret = max8925_set_bits(chip->i2c, data->reg_mode_cntl, 0xfe, value);
        if (ret < 0)
                goto out_brt;
-
        backlight_update_status(bl);
        return 0;
 out_brt: