diff options
Diffstat (limited to 'drivers/video/backlight/gpio_backlight.c')
| -rw-r--r-- | drivers/video/backlight/gpio_backlight.c | 76 |
1 files changed, 57 insertions, 19 deletions
diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c index 5fa217f9f44..1cea68848f1 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 @@ struct gpio_backlight { int gpio; int active; + int def_value; }; static int gpio_backlight_update_status(struct backlight_device *bl) @@ -35,7 +38,8 @@ static int gpio_backlight_update_status(struct backlight_device *bl) bl->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK)) brightness = 0; - gpio_set_value(gbl->gpio, brightness ? gbl->active : !gbl->active); + gpio_set_value_cansleep(gbl->gpio, + brightness ? gbl->active : !gbl->active); return 0; } @@ -60,16 +64,42 @@ static const struct backlight_ops gpio_backlight_ops = { .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 = pdev->dev.platform_data; + struct gpio_backlight_platform_data *pdata = + dev_get_platdata(&pdev->dev); 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; } @@ -78,14 +108,22 @@ static int gpio_backlight_probe(struct platform_device *pdev) 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; @@ -94,35 +132,35 @@ static int gpio_backlight_probe(struct platform_device *pdev) memset(&props, 0, sizeof(props)); props.type = BACKLIGHT_RAW; props.max_brightness = 1; - bl = backlight_device_register(dev_name(&pdev->dev), &pdev->dev, gbl, - &gpio_backlight_ops, &props); + bl = devm_backlight_device_register(&pdev->dev, dev_name(&pdev->dev), + &pdev->dev, gbl, &gpio_backlight_ops, + &props); if (IS_ERR(bl)) { dev_err(&pdev->dev, "failed to register backlight\n"); 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; } -static int gpio_backlight_remove(struct platform_device *pdev) -{ - struct backlight_device *bl = platform_get_drvdata(pdev); - - backlight_device_unregister(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, - .remove = gpio_backlight_remove, }; module_platform_driver(gpio_backlight_driver); |