xref: /openbmc/u-boot/drivers/led/led_gpio.c (revision 61a4392a)
1 /*
2  * Copyright (c) 2015 Google, Inc
3  * Written by Simon Glass <sjg@chromium.org>
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #include <common.h>
9 #include <dm.h>
10 #include <errno.h>
11 #include <led.h>
12 #include <asm/gpio.h>
13 #include <dm/lists.h>
14 
15 DECLARE_GLOBAL_DATA_PTR;
16 
17 struct led_gpio_priv {
18 	struct gpio_desc gpio;
19 };
20 
21 static int gpio_led_set_on(struct udevice *dev, int on)
22 {
23 	struct led_gpio_priv *priv = dev_get_priv(dev);
24 
25 	if (!dm_gpio_is_valid(&priv->gpio))
26 		return -EREMOTEIO;
27 
28 	return dm_gpio_set_value(&priv->gpio, on);
29 }
30 
31 static int led_gpio_probe(struct udevice *dev)
32 {
33 	struct led_uclass_plat *uc_plat = dev_get_uclass_platdata(dev);
34 	struct led_gpio_priv *priv = dev_get_priv(dev);
35 
36 	/* Ignore the top-level LED node */
37 	if (!uc_plat->label)
38 		return 0;
39 	return gpio_request_by_name(dev, "gpios", 0, &priv->gpio, GPIOD_IS_OUT);
40 }
41 
42 static int led_gpio_remove(struct udevice *dev)
43 {
44 	/*
45 	 * The GPIO driver may have already been removed. We will need to
46 	 * address this more generally.
47 	 */
48 #ifndef CONFIG_SANDBOX
49 	struct led_gpio_priv *priv = dev_get_priv(dev);
50 
51 	if (dm_gpio_is_valid(&priv->gpio))
52 		dm_gpio_free(dev, &priv->gpio);
53 #endif
54 
55 	return 0;
56 }
57 
58 static int led_gpio_bind(struct udevice *parent)
59 {
60 	const void *blob = gd->fdt_blob;
61 	struct udevice *dev;
62 	int node;
63 	int ret;
64 
65 	for (node = fdt_first_subnode(blob, parent->of_offset);
66 	     node > 0;
67 	     node = fdt_next_subnode(blob, node)) {
68 		struct led_uclass_plat *uc_plat;
69 		const char *label;
70 
71 		label = fdt_getprop(blob, node, "label", NULL);
72 		if (!label) {
73 			debug("%s: node %s has no label\n", __func__,
74 			      fdt_get_name(blob, node, NULL));
75 			return -EINVAL;
76 		}
77 		ret = device_bind_driver_to_node(parent, "gpio_led",
78 						 fdt_get_name(blob, node, NULL),
79 						 node, &dev);
80 		if (ret)
81 			return ret;
82 		uc_plat = dev_get_uclass_platdata(dev);
83 		uc_plat->label = label;
84 	}
85 
86 	return 0;
87 }
88 
89 static const struct led_ops gpio_led_ops = {
90 	.set_on		= gpio_led_set_on,
91 };
92 
93 static const struct udevice_id led_gpio_ids[] = {
94 	{ .compatible = "gpio-leds" },
95 	{ }
96 };
97 
98 U_BOOT_DRIVER(led_gpio) = {
99 	.name	= "gpio_led",
100 	.id	= UCLASS_LED,
101 	.of_match = led_gpio_ids,
102 	.ops	= &gpio_led_ops,
103 	.priv_auto_alloc_size = sizeof(struct led_gpio_priv),
104 	.bind	= led_gpio_bind,
105 	.probe	= led_gpio_probe,
106 	.remove	= led_gpio_remove,
107 };
108