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 <asm/gpio.h>
12 #include <dm/lists.h>
13
14 struct led_gpio_priv {
15 struct gpio_desc gpio;
16 };
17
gpio_led_set_state(struct udevice * dev,enum led_state_t state)18 static int gpio_led_set_state(struct udevice *dev, enum led_state_t state)
19 {
20 struct led_gpio_priv *priv = dev_get_priv(dev);
21 int ret;
22
23 if (!dm_gpio_is_valid(&priv->gpio))
24 return -EREMOTEIO;
25 switch (state) {
26 case LEDST_OFF:
27 case LEDST_ON:
28 break;
29 case LEDST_TOGGLE:
30 ret = dm_gpio_get_value(&priv->gpio);
31 if (ret < 0)
32 return ret;
33 state = !ret;
34 break;
35 default:
36 return -ENOSYS;
37 }
38
39 return dm_gpio_set_value(&priv->gpio, state);
40 }
41
gpio_led_get_state(struct udevice * dev)42 static enum led_state_t gpio_led_get_state(struct udevice *dev)
43 {
44 struct led_gpio_priv *priv = dev_get_priv(dev);
45 int ret;
46
47 if (!dm_gpio_is_valid(&priv->gpio))
48 return -EREMOTEIO;
49 ret = dm_gpio_get_value(&priv->gpio);
50 if (ret < 0)
51 return ret;
52
53 return ret ? LEDST_ON : LEDST_OFF;
54 }
55
led_gpio_probe(struct udevice * dev)56 static int led_gpio_probe(struct udevice *dev)
57 {
58 struct led_uc_plat *uc_plat = dev_get_uclass_platdata(dev);
59 struct led_gpio_priv *priv = dev_get_priv(dev);
60 int ret;
61
62 /* Ignore the top-level LED node */
63 if (!uc_plat->label)
64 return 0;
65
66 ret = gpio_request_by_name(dev, "gpios", 0, &priv->gpio, GPIOD_IS_OUT);
67 if (ret)
68 return ret;
69
70 return 0;
71 }
72
led_gpio_remove(struct udevice * dev)73 static int led_gpio_remove(struct udevice *dev)
74 {
75 /*
76 * The GPIO driver may have already been removed. We will need to
77 * address this more generally.
78 */
79 #ifndef CONFIG_SANDBOX
80 struct led_gpio_priv *priv = dev_get_priv(dev);
81
82 if (dm_gpio_is_valid(&priv->gpio))
83 dm_gpio_free(dev, &priv->gpio);
84 #endif
85
86 return 0;
87 }
88
led_gpio_bind(struct udevice * parent)89 static int led_gpio_bind(struct udevice *parent)
90 {
91 struct udevice *dev;
92 ofnode node;
93 int ret;
94
95 dev_for_each_subnode(node, parent) {
96 struct led_uc_plat *uc_plat;
97 const char *label;
98
99 label = ofnode_read_string(node, "label");
100 if (!label) {
101 debug("%s: node %s has no label\n", __func__,
102 ofnode_get_name(node));
103 return -EINVAL;
104 }
105 ret = device_bind_driver_to_node(parent, "gpio_led",
106 ofnode_get_name(node),
107 node, &dev);
108 if (ret)
109 return ret;
110 uc_plat = dev_get_uclass_platdata(dev);
111 uc_plat->label = label;
112 }
113
114 return 0;
115 }
116
117 static const struct led_ops gpio_led_ops = {
118 .set_state = gpio_led_set_state,
119 .get_state = gpio_led_get_state,
120 };
121
122 static const struct udevice_id led_gpio_ids[] = {
123 { .compatible = "gpio-leds" },
124 { }
125 };
126
127 U_BOOT_DRIVER(led_gpio) = {
128 .name = "gpio_led",
129 .id = UCLASS_LED,
130 .of_match = led_gpio_ids,
131 .ops = &gpio_led_ops,
132 .priv_auto_alloc_size = sizeof(struct led_gpio_priv),
133 .bind = led_gpio_bind,
134 .probe = led_gpio_probe,
135 .remove = led_gpio_remove,
136 };
137