1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
4  * Author: Patrick Delaunay <patrick.delaunay@st.com>
5  */
6 
7 #include <common.h>
8 #include <dm.h>
9 #include <backlight.h>
10 #include <asm/gpio.h>
11 
12 struct gpio_backlight_priv {
13 	struct gpio_desc gpio;
14 	bool def_value;
15 };
16 
17 static int gpio_backlight_enable(struct udevice *dev)
18 {
19 	struct gpio_backlight_priv *priv = dev_get_priv(dev);
20 
21 	dm_gpio_set_value(&priv->gpio, 1);
22 
23 	return 0;
24 }
25 
26 static int gpio_backlight_ofdata_to_platdata(struct udevice *dev)
27 {
28 	struct gpio_backlight_priv *priv = dev_get_priv(dev);
29 	int ret;
30 
31 	ret = gpio_request_by_name(dev, "gpios", 0, &priv->gpio,
32 				   GPIOD_IS_OUT);
33 	if (ret) {
34 		debug("%s: Warning: cannot get GPIO: ret=%d\n",
35 		      __func__, ret);
36 		return ret;
37 	}
38 
39 	priv->def_value = dev_read_bool(dev, "default-on");
40 
41 	return 0;
42 }
43 
44 static int gpio_backlight_probe(struct udevice *dev)
45 {
46 	struct gpio_backlight_priv *priv = dev_get_priv(dev);
47 
48 	if (priv->def_value)
49 		gpio_backlight_enable(dev);
50 
51 	return 0;
52 }
53 
54 static const struct backlight_ops gpio_backlight_ops = {
55 	.enable	= gpio_backlight_enable,
56 };
57 
58 static const struct udevice_id gpio_backlight_ids[] = {
59 	{ .compatible = "gpio-backlight" },
60 	{ }
61 };
62 
63 U_BOOT_DRIVER(gpio_backlight) = {
64 	.name	= "gpio_backlight",
65 	.id	= UCLASS_PANEL_BACKLIGHT,
66 	.of_match = gpio_backlight_ids,
67 	.ops	= &gpio_backlight_ops,
68 	.ofdata_to_platdata	= gpio_backlight_ofdata_to_platdata,
69 	.probe		= gpio_backlight_probe,
70 	.priv_auto_alloc_size	= sizeof(struct gpio_backlight_priv),
71 };
72