suspend.c

  1#include <stdbool.h>
  2#include <avr/sleep.h>
  3#include <avr/wdt.h>
  4#include <avr/interrupt.h>
  5#include "suspend.h"
  6#include "action.h"
  7#include "timer.h"
  8
  9#ifdef PROTOCOL_LUFA
 10#    include "lufa.h"
 11#endif
 12#ifdef PROTOCOL_VUSB
 13#    include "vusb.h"
 14#endif
 15
 16// TODO: This needs some cleanup
 17
 18#if !defined(NO_SUSPEND_POWER_DOWN) && defined(WDT_vect)
 19
 20// clang-format off
 21#define wdt_intr_enable(value) \
 22__asm__ __volatile__ ( \
 23    "in __tmp_reg__,__SREG__" "\n\t" \
 24    "cli" "\n\t" \
 25    "wdr" "\n\t" \
 26    "sts %0,%1" "\n\t" \
 27    "out __SREG__,__tmp_reg__" "\n\t" \
 28    "sts %0,%2" "\n\t" \
 29    : /* no outputs */ \
 30    : "M" (_SFR_MEM_ADDR(_WD_CONTROL_REG)), \
 31    "r" (_BV(_WD_CHANGE_BIT) | _BV(WDE)), \
 32    "r" ((uint8_t) ((value & 0x08 ? _WD_PS3_MASK : 0x00) | _BV(WDIE) | (value & 0x07))) \
 33    : "r0" \
 34)
 35// clang-format on
 36
 37/** \brief Power down MCU with watchdog timer
 38 *
 39 * wdto: watchdog timer timeout defined in <avr/wdt.h>
 40 *          WDTO_15MS
 41 *          WDTO_30MS
 42 *          WDTO_60MS
 43 *          WDTO_120MS
 44 *          WDTO_250MS
 45 *          WDTO_500MS
 46 *          WDTO_1S
 47 *          WDTO_2S
 48 *          WDTO_4S
 49 *          WDTO_8S
 50 */
 51static uint8_t wdt_timeout = 0;
 52
 53/** \brief Power down
 54 *
 55 * FIXME: needs doc
 56 */
 57static void power_down(uint8_t wdto) {
 58    wdt_timeout = wdto;
 59
 60    // Watchdog Interrupt Mode
 61    wdt_intr_enable(wdto);
 62
 63    // TODO: more power saving
 64    // See PicoPower application note
 65    // - I/O port input with pullup
 66    // - prescale clock
 67    // - BOD disable
 68    // - Power Reduction Register PRR
 69    set_sleep_mode(SLEEP_MODE_PWR_DOWN);
 70    sleep_enable();
 71    sei();
 72    sleep_cpu();
 73    sleep_disable();
 74
 75    // Disable watchdog after sleep
 76    wdt_disable();
 77}
 78
 79/* watchdog timeout */
 80ISR(WDT_vect) {
 81    // compensate timer for sleep
 82    switch (wdt_timeout) {
 83        case WDTO_15MS:
 84            timer_count += 15 + 2; // WDTO_15MS + 2(from observation)
 85            break;
 86        default:;
 87    }
 88}
 89
 90#endif
 91
 92/** \brief Suspend power down
 93 *
 94 * FIXME: needs doc
 95 */
 96void suspend_power_down(void) {
 97#ifdef PROTOCOL_LUFA
 98    if (USB_DeviceState == DEVICE_STATE_Configured) return;
 99#endif
100#ifdef PROTOCOL_VUSB
101    if (!vusb_suspended) return;
102#endif
103
104    suspend_power_down_quantum();
105
106#ifndef NO_SUSPEND_POWER_DOWN
107    // Enter sleep state if possible (ie, the MCU has a watchdog timeout interrupt)
108#    if defined(WDT_vect)
109    power_down(WDTO_15MS);
110#    endif
111#endif
112}
113
114/** \brief run immediately after wakeup
115 *
116 * FIXME: needs doc
117 */
118void suspend_wakeup_init(void) {
119    // clear keyboard state
120    clear_keyboard();
121
122    suspend_wakeup_init_quantum();
123}