1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (c) 2015 Google, Inc
4 * Written by Simon Glass <sjg@chromium.org>
5 */
6
7 #include <common.h>
8 #include <dm.h>
9 #include <errno.h>
10 #include <led.h>
11 #include <log.h>
12 #include <malloc.h>
13 #include <asm/gpio.h>
14 #include <dm/lists.h>
15
16 struct led_gpio_priv {
17 struct gpio_desc gpio;
18 };
19
gpio_led_set_state(struct udevice * dev,enum led_state_t state)20 static int gpio_led_set_state(struct udevice *dev, enum led_state_t state)
21 {
22 struct led_gpio_priv *priv = dev_get_priv(dev);
23 int ret;
24
25 if (!dm_gpio_is_valid(&priv->gpio))
26 return -EREMOTEIO;
27 switch (state) {
28 case LEDST_OFF:
29 case LEDST_ON:
30 break;
31 case LEDST_TOGGLE:
32 ret = dm_gpio_get_value(&priv->gpio);
33 if (ret < 0)
34 return ret;
35 state = !ret;
36 break;
37 default:
38 return -ENOSYS;
39 }
40
41 return dm_gpio_set_value(&priv->gpio, state);
42 }
43
gpio_led_get_state(struct udevice * dev)44 static enum led_state_t gpio_led_get_state(struct udevice *dev)
45 {
46 struct led_gpio_priv *priv = dev_get_priv(dev);
47 int ret;
48
49 if (!dm_gpio_is_valid(&priv->gpio))
50 return -EREMOTEIO;
51 ret = dm_gpio_get_value(&priv->gpio);
52 if (ret < 0)
53 return ret;
54
55 return ret ? LEDST_ON : LEDST_OFF;
56 }
57
led_gpio_probe(struct udevice * dev)58 static int led_gpio_probe(struct udevice *dev)
59 {
60 struct led_uc_plat *uc_plat = dev_get_uclass_plat(dev);
61 struct led_gpio_priv *priv = dev_get_priv(dev);
62 int ret;
63
64 /* Ignore the top-level LED node */
65 if (!uc_plat->label)
66 return 0;
67
68 ret = gpio_request_by_name(dev, "gpios", 0, &priv->gpio, GPIOD_IS_OUT);
69 if (ret)
70 return ret;
71
72 return 0;
73 }
74
led_gpio_remove(struct udevice * dev)75 static int led_gpio_remove(struct udevice *dev)
76 {
77 /*
78 * The GPIO driver may have already been removed. We will need to
79 * address this more generally.
80 */
81 #ifndef CONFIG_SANDBOX
82 struct led_gpio_priv *priv = dev_get_priv(dev);
83
84 if (dm_gpio_is_valid(&priv->gpio))
85 dm_gpio_free(dev, &priv->gpio);
86 #endif
87
88 return 0;
89 }
90
led_gpio_bind(struct udevice * parent)91 static int led_gpio_bind(struct udevice *parent)
92 {
93 struct udevice *dev;
94 ofnode node;
95 int ret;
96
97 dev_for_each_subnode(node, parent) {
98 struct led_uc_plat *uc_plat;
99 const char *label;
100
101 label = ofnode_read_string(node, "label");
102 if (!label)
103 label = ofnode_get_name(node);
104 ret = device_bind_driver_to_node(parent, "gpio_led",
105 ofnode_get_name(node),
106 node, &dev);
107 if (ret)
108 return ret;
109 uc_plat = dev_get_uclass_plat(dev);
110 uc_plat->label = label;
111 }
112
113 return 0;
114 }
115
116 static const struct led_ops gpio_led_ops = {
117 .set_state = gpio_led_set_state,
118 .get_state = gpio_led_get_state,
119 };
120
121 static const struct udevice_id led_gpio_ids[] = {
122 { .compatible = "gpio-leds" },
123 { }
124 };
125
126 U_BOOT_DRIVER(led_gpio) = {
127 .name = "gpio_led",
128 .id = UCLASS_LED,
129 .of_match = led_gpio_ids,
130 .ops = &gpio_led_ops,
131 .priv_auto = sizeof(struct led_gpio_priv),
132 .bind = led_gpio_bind,
133 .probe = led_gpio_probe,
134 .remove = led_gpio_remove,
135 };
136