include/button.h

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2 /*
   3  * Copyright (C) 2020 Philippe Reynes <philippe.reynes@softathome.com>
   4  */
   5
   6 #ifndef __BUTTON_H
   7 #define __BUTTON_H
   8
   9 struct udevice;
  10
  11 /**
  12  * struct button_uc_plat - Platform data the uclass stores about each device
  13  *
  14  * @label:      Button label
  15  */
  16 struct button_uc_plat {
  17         const char *label;
  18 };
  19
  20 /**
  21  * enum button_state_t - State used for button
  22  * - BUTTON_OFF - Button is not pressed
  23  * - BUTTON_ON - Button is pressed
  24  * - BUTTON_COUNT - Number of button state
  25  */
  26 enum button_state_t {
  27         BUTTON_OFF = 0,
  28         BUTTON_ON = 1,
  29         BUTTON_COUNT,
  30 };
  31
  32 struct button_ops {
  33         /**
  34          * get_state() - get the state of a button
  35          *
  36          * @dev:        button device to change
  37          * @return button state button_state_t, or -ve on error
  38          */
  39         enum button_state_t (*get_state)(struct udevice *dev);
  40
  41         /**
  42          * get_code() - get linux event code of a button
  43          *
  44          * @dev:        button device to change
  45          * @return button code, or -ENODATA on error
  46          */
  47         int (*get_code)(struct udevice *dev);
  48 };
  49
  50 #define button_get_ops(dev)     ((struct button_ops *)(dev)->driver->ops)
  51
  52 /**
  53  * button_get_by_label() - Find a button device by label
  54  *
  55  * @label:      button label to look up
  56  * @devp:       Returns the associated device, if found
  57  * Return: 0 if found, -ENODEV if not found, other -ve on error
  58  */
  59 int button_get_by_label(const char *label, struct udevice **devp);
  60
  61 /**
  62  * button_get_state() - get the state of a button
  63  *
  64  * @dev:        button device to change
  65  * Return: button state button_state_t, or -ve on error
  66  */
  67 enum button_state_t button_get_state(struct udevice *dev);
  68
  69 /**
  70  * button_get_code() - get linux event code of a button
  71  *
  72  * @dev:        button device to change
  73  * @return button code, or -ve on error
  74  */
  75 int button_get_code(struct udevice *dev);
  76
  77 #endif