include/led.h

   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 struct udevice;
  11
  12 enum led_state_t {
  13         LEDST_OFF = 0,
  14         LEDST_ON = 1,
  15         LEDST_TOGGLE,
  16 #ifdef CONFIG_LED_BLINK
  17         LEDST_BLINK,
  18 #endif
  19
  20         LEDST_COUNT,
  21 };
  22
  23 /**
  24  * struct led_uc_plat - Platform data the uclass stores about each device
  25  *
  26  * @label:      LED label
  27  * @default_state:      LED default state
  28  */
  29 struct led_uc_plat {
  30         const char *label;
  31         enum led_state_t default_state;
  32 };
  33
  34 /**
  35  * struct led_uc_priv - Private data the uclass stores about each device
  36  *
  37  * @period_ms:  Flash period in milliseconds
  38  */
  39 struct led_uc_priv {
  40         int period_ms;
  41 };
  42
  43 struct led_ops {
  44         /**
  45          * set_state() - set the state of an LED
  46          *
  47          * @dev:        LED device to change
  48          * @state:      LED state to set
  49          * @return 0 if OK, -ve on error
  50          */
  51         int (*set_state)(struct udevice *dev, enum led_state_t state);
  52
  53         /**
  54          * led_get_state() - get the state of an LED
  55          *
  56          * @dev:        LED device to change
  57          * @return LED state led_state_t, or -ve on error
  58          */
  59         enum led_state_t (*get_state)(struct udevice *dev);
  60
  61 #ifdef CONFIG_LED_BLINK
  62         /**
  63          * led_set_period() - set the blink period of an LED
  64          *
  65          * Thie records the period if supported, or returns -ENOSYS if not.
  66          * To start the LED blinking, use set_state().
  67          *
  68          * @dev:        LED device to change
  69          * @period_ms:  LED blink period in milliseconds
  70          * @return 0 if OK, -ve on error
  71          */
  72         int (*set_period)(struct udevice *dev, int period_ms);
  73 #endif
  74 };
  75
  76 #define led_get_ops(dev)        ((struct led_ops *)(dev)->driver->ops)
  77
  78 /**
  79  * led_get_by_label() - Find an LED device by label
  80  *
  81  * @label:      LED label to look up
  82  * @devp:       Returns the associated device, if found
  83  * Return: 0 if found, -ENODEV if not found, other -ve on error
  84  */
  85 int led_get_by_label(const char *label, struct udevice **devp);
  86
  87 /**
  88  * led_set_state() - set the state of an LED
  89  *
  90  * @dev:        LED device to change
  91  * @state:      LED state to set
  92  * Return: 0 if OK, -ve on error
  93  */
  94 int led_set_state(struct udevice *dev, enum led_state_t state);
  95
  96 /**
  97  * led_get_state() - get the state of an LED
  98  *
  99  * @dev:        LED device to change
 100  * Return: LED state led_state_t, or -ve on error
 101  */
 102 enum led_state_t led_get_state(struct udevice *dev);
 103
 104 /**
 105  * led_set_period() - set the blink period of an LED
 106  *
 107  * @dev:        LED device to change
 108  * @period_ms:  LED blink period in milliseconds
 109  * Return: 0 if OK, -ve on error
 110  */
 111 int led_set_period(struct udevice *dev, int period_ms);
 112
 113 /**
 114  * led_bind_generic() - bind children of parent to given driver
 115  *
 116  * @parent:      Top-level LED device
 117  * @driver_name: Driver for handling individual child nodes
 118  */
 119 int led_bind_generic(struct udevice *parent, const char *driver_name);
 120
 121 #endif