xref: /openbmc/u-boot/include/led.h (revision 861b85c4)
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 #ifndef __LED_H
8 #define __LED_H
9 
10 /**
11  * struct led_uc_plat - Platform data the uclass stores about each device
12  *
13  * @label:	LED label
14  */
15 struct led_uc_plat {
16 	const char *label;
17 };
18 
19 /**
20  * struct led_uc_priv - Private data the uclass stores about each device
21  *
22  * @period_ms:	Flash period in milliseconds
23  */
24 struct led_uc_priv {
25 	int period_ms;
26 };
27 
28 enum led_state_t {
29 	LEDST_OFF = 0,
30 	LEDST_ON = 1,
31 	LEDST_TOGGLE,
32 #ifdef CONFIG_LED_BLINK
33 	LEDST_BLINK,
34 #endif
35 
36 	LEDST_COUNT,
37 };
38 
39 struct led_ops {
40 	/**
41 	 * set_state() - set the state of an LED
42 	 *
43 	 * @dev:	LED device to change
44 	 * @state:	LED state to set
45 	 * @return 0 if OK, -ve on error
46 	 */
47 	int (*set_state)(struct udevice *dev, enum led_state_t state);
48 
49 	/**
50 	 * led_get_state() - get the state of an LED
51 	 *
52 	 * @dev:	LED device to change
53 	 * @return LED state led_state_t, or -ve on error
54 	 */
55 	enum led_state_t (*get_state)(struct udevice *dev);
56 
57 #ifdef CONFIG_LED_BLINK
58 	/**
59 	 * led_set_period() - set the blink period of an LED
60 	 *
61 	 * Thie records the period if supported, or returns -ENOSYS if not.
62 	 * To start the LED blinking, use set_state().
63 	 *
64 	 * @dev:	LED device to change
65 	 * @period_ms:	LED blink period in milliseconds
66 	 * @return 0 if OK, -ve on error
67 	 */
68 	int (*set_period)(struct udevice *dev, int period_ms);
69 #endif
70 };
71 
72 #define led_get_ops(dev)	((struct led_ops *)(dev)->driver->ops)
73 
74 /**
75  * led_get_by_label() - Find an LED device by label
76  *
77  * @label:	LED label to look up
78  * @devp:	Returns the associated device, if found
79  * @return 0 if found, -ENODEV if not found, other -ve on error
80  */
81 int led_get_by_label(const char *label, struct udevice **devp);
82 
83 /**
84  * led_set_state() - set the state of an LED
85  *
86  * @dev:	LED device to change
87  * @state:	LED state to set
88  * @return 0 if OK, -ve on error
89  */
90 int led_set_state(struct udevice *dev, enum led_state_t state);
91 
92 /**
93  * led_get_state() - get the state of an LED
94  *
95  * @dev:	LED device to change
96  * @return LED state led_state_t, or -ve on error
97  */
98 enum led_state_t led_get_state(struct udevice *dev);
99 
100 /**
101  * led_set_period() - set the blink period of an LED
102  *
103  * @dev:	LED device to change
104  * @period_ms:	LED blink period in milliseconds
105  * @return 0 if OK, -ve on error
106  */
107 int led_set_period(struct udevice *dev, int period_ms);
108 
109 /**
110  * led_default_state() - set the default state for all the LED
111  *
112  * This enables all leds which have default state.
113  * see Documentation/devicetree/bindings/leds/common.txt
114  *
115  */
116 int led_default_state(void);
117 
118 #endif
119