include/sysreset.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 __SYSRESET_H
   8 #define __SYSRESET_H
   9
  10 struct udevice;
  11
  12 /**
  13  * enum sysreset_t - system reset types
  14  */
  15 enum sysreset_t {
  16         /** @SYSRESET_WARM: reset CPU, keep GPIOs active */
  17         SYSRESET_WARM,
  18         /** @SYSRESET_COLD: reset CPU and GPIOs */
  19         SYSRESET_COLD,
  20         /** @SYSRESET_POWER: reset PMIC (remove and restore power) */
  21         SYSRESET_POWER,
  22         /** @SYSRESET_POWER_OFF: turn off power */
  23         SYSRESET_POWER_OFF,
  24         /** @SYSRESET_COUNT: number of available reset types */
  25         SYSRESET_COUNT,
  26 };
  27
  28 /**
  29  * struct sysreset_ops - operations of system reset drivers
  30  */
  31 struct sysreset_ops {
  32         /**
  33          * @request:    request a sysreset of the given type
  34          *
  35          * Note that this function may return before the reset takes effect.
  36          *
  37          * @dev:        Device to be used for system reset
  38          * @type:       Reset type to request
  39          * Return:
  40          * -EINPROGRESS if the reset has been started and
  41          * will complete soon, -EPROTONOSUPPORT if not supported
  42          * by this device, 0 if the reset has already happened
  43          * (in which case this method will not actually return)
  44          */
  45         int (*request)(struct udevice *dev, enum sysreset_t type);
  46         /**
  47          * @get_status: get printable reset status information
  48          *
  49          * @dev:        Device to check
  50          * @buf:        Buffer to receive the textual reset information
  51          * @size:       Size of the passed buffer
  52          * Return:      0 if OK, -ve on error
  53          */
  54         int (*get_status)(struct udevice *dev, char *buf, int size);
  55
  56         /**
  57          * @get_last:   get information on the last reset
  58          *
  59          * @dev:        Device to check
  60          * Return:      last reset state (enum :enum:`sysreset_t`) or -ve error
  61          */
  62         int (*get_last)(struct udevice *dev);
  63 };
  64
  65 #define sysreset_get_ops(dev)        ((struct sysreset_ops *)(dev)->driver->ops)
  66
  67 /**
  68  * sysreset_request() - request a sysreset
  69  *
  70  * @dev:        Device to be used for system reset
  71  * @type:       Reset type to request
  72  * Return:      0 if OK, -EPROTONOSUPPORT if not supported by this device
  73  */
  74 int sysreset_request(struct udevice *dev, enum sysreset_t type);
  75
  76 /**
  77  * sysreset_get_status() - get printable reset status information
  78  *
  79  * @dev:        Device to check
  80  * @buf:        Buffer to receive the textual reset information
  81  * @size:       Size of the passed buffer
  82  * Return:       0 if OK, -ve on error
  83  */
  84 int sysreset_get_status(struct udevice *dev, char *buf, int size);
  85
  86 /**
  87  * sysreset_get_last() - get information on the last reset
  88  *
  89  * @dev:        Device to check
  90  * Return:      last reset state (enum sysreset_t) or -ve error
  91  */
  92 int sysreset_get_last(struct udevice *dev);
  93
  94 /**
  95  * sysreset_walk() - cause a system reset
  96  *
  97  * This works through the available sysreset devices until it finds one that can
  98  * perform a reset. If the provided sysreset type is not available, the next one
  99  * will be tried.
 100  *
 101  * If this function fails to reset, it will display a message and halt
 102  *
 103  * @type:       Reset type to request
 104  * Return:      -EINPROGRESS if a reset is in progress, -ENOSYS if not available
 105  */
 106 int sysreset_walk(enum sysreset_t type);
 107
 108 /**
 109  * sysreset_get_last_walk() - get information on the last reset
 110  *
 111  * This works through the available sysreset devices until it finds one that can
 112  * perform a reset. If the provided sysreset type is not available, the next one
 113  * will be tried.
 114  *
 115  * If no device prives the information, this function returns -ENOENT
 116  *
 117  * Return:      last reset state (enum sysreset_t) or -ve error
 118  */
 119 int sysreset_get_last_walk(void);
 120
 121 /**
 122  * sysreset_walk_halt() - try to reset, otherwise halt
 123  *
 124  * This calls sysreset_walk(). If it returns, indicating that reset is not
 125  * supported, it prints a message and halts.
 126  *
 127  * @type:       Reset type to request
 128  */
 129 void sysreset_walk_halt(enum sysreset_t type);
 130
 131 /**
 132  * reset_cpu() - calls sysreset_walk(SYSRESET_WARM)
 133  */
 134 void reset_cpu(void);
 135
 136 /**
 137  * sysreset_register_wdt() - register a watchdog for use with sysreset
 138  *
 139  * This registers the given watchdog timer to be used to reset the system.
 140  *
 141  * @dev:        WDT device
 142  * @return:     0 if OK, -errno if error
 143  */
 144 int sysreset_register_wdt(struct udevice *dev);
 145
 146 #endif