backlight: gpio-backlight: Add DT support
Signed-off-by: Denis Carikli <denis@eukrea.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c
index 81fb127..a2eba12 100644
--- a/drivers/video/backlight/gpio_backlight.c
+++ b/drivers/video/backlight/gpio_backlight.c
@@ -13,6 +13,8 @@
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
#include <linux/platform_data/gpio_backlight.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
@@ -23,6 +25,7 @@
int gpio;
int active;
+ int def_value;
};
static int gpio_backlight_update_status(struct backlight_device *bl)
@@ -60,6 +63,29 @@
.check_fb = gpio_backlight_check_fb,
};
+static int gpio_backlight_probe_dt(struct platform_device *pdev,
+ struct gpio_backlight *gbl)
+{
+ struct device_node *np = pdev->dev.of_node;
+ enum of_gpio_flags gpio_flags;
+
+ gbl->gpio = of_get_gpio_flags(np, 0, &gpio_flags);
+
+ if (!gpio_is_valid(gbl->gpio)) {
+ if (gbl->gpio != -EPROBE_DEFER) {
+ dev_err(&pdev->dev,
+ "Error: The gpios parameter is missing or invalid.\n");
+ }
+ return gbl->gpio;
+ }
+
+ gbl->active = (gpio_flags & OF_GPIO_ACTIVE_LOW) ? 0 : 1;
+
+ gbl->def_value = of_property_read_bool(np, "default-on");
+
+ return 0;
+}
+
static int gpio_backlight_probe(struct platform_device *pdev)
{
struct gpio_backlight_platform_data *pdata =
@@ -67,10 +93,12 @@
struct backlight_properties props;
struct backlight_device *bl;
struct gpio_backlight *gbl;
+ struct device_node *np = pdev->dev.of_node;
int ret;
- if (!pdata) {
- dev_err(&pdev->dev, "failed to find platform data\n");
+ if (!pdata && !np) {
+ dev_err(&pdev->dev,
+ "failed to find platform data or device tree node.\n");
return -ENODEV;
}
@@ -79,14 +107,22 @@
return -ENOMEM;
gbl->dev = &pdev->dev;
- gbl->fbdev = pdata->fbdev;
- gbl->gpio = pdata->gpio;
- gbl->active = pdata->active_low ? 0 : 1;
+
+ if (np) {
+ ret = gpio_backlight_probe_dt(pdev, gbl);
+ if (ret)
+ return ret;
+ } else {
+ gbl->fbdev = pdata->fbdev;
+ gbl->gpio = pdata->gpio;
+ gbl->active = pdata->active_low ? 0 : 1;
+ gbl->def_value = pdata->def_value;
+ }
ret = devm_gpio_request_one(gbl->dev, gbl->gpio, GPIOF_DIR_OUT |
(gbl->active ? GPIOF_INIT_LOW
: GPIOF_INIT_HIGH),
- pdata->name);
+ pdata ? pdata->name : "backlight");
if (ret < 0) {
dev_err(&pdev->dev, "unable to request GPIO\n");
return ret;
@@ -103,17 +139,25 @@
return PTR_ERR(bl);
}
- bl->props.brightness = pdata->def_value;
+ bl->props.brightness = gbl->def_value;
backlight_update_status(bl);
platform_set_drvdata(pdev, bl);
return 0;
}
+#ifdef CONFIG_OF
+static struct of_device_id gpio_backlight_of_match[] = {
+ { .compatible = "gpio-backlight" },
+ { /* sentinel */ }
+};
+#endif
+
static struct platform_driver gpio_backlight_driver = {
.driver = {
.name = "gpio-backlight",
.owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(gpio_backlight_of_match),
},
.probe = gpio_backlight_probe,
};