diff options
Diffstat (limited to 'drivers/acpi/sleep.c')
| -rw-r--r-- | drivers/acpi/sleep.c | 126 |
1 files changed, 120 insertions, 6 deletions
diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c index a6574d626340..be17664736b2 100644 --- a/drivers/acpi/sleep.c +++ b/drivers/acpi/sleep.c @@ -650,17 +650,108 @@ static const struct platform_suspend_ops acpi_suspend_ops_old = { .recover = acpi_pm_finish, }; +static bool s2idle_in_progress; +static bool s2idle_wakeup; + +/* + * On platforms supporting the Low Power S0 Idle interface there is an ACPI + * device object with the PNP0D80 compatible device ID (System Power Management + * Controller) and a specific _DSM method under it. That method, if present, + * can be used to indicate to the platform that the OS is transitioning into a + * low-power state in which certain types of activity are not desirable or that + * it is leaving such a state, which allows the platform to adjust its operation + * mode accordingly. + */ +static const struct acpi_device_id lps0_device_ids[] = { + {"PNP0D80", }, + {"", }, +}; + +#define ACPI_LPS0_DSM_UUID "c4eb40a0-6cd2-11e2-bcfd-0800200c9a66" + +#define ACPI_LPS0_SCREEN_OFF 3 +#define ACPI_LPS0_SCREEN_ON 4 +#define ACPI_LPS0_ENTRY 5 +#define ACPI_LPS0_EXIT 6 + +#define ACPI_S2IDLE_FUNC_MASK ((1 << ACPI_LPS0_ENTRY) | (1 << ACPI_LPS0_EXIT)) + +static acpi_handle lps0_device_handle; +static guid_t lps0_dsm_guid; +static char lps0_dsm_func_mask; + +static void acpi_sleep_run_lps0_dsm(unsigned int func) +{ + union acpi_object *out_obj; + + if (!(lps0_dsm_func_mask & (1 << func))) + return; + + out_obj = acpi_evaluate_dsm(lps0_device_handle, &lps0_dsm_guid, 1, func, NULL); + ACPI_FREE(out_obj); + + acpi_handle_debug(lps0_device_handle, "_DSM function %u evaluation %s\n", + func, out_obj ? "successful" : "failed"); +} + +static int lps0_device_attach(struct acpi_device *adev, + const struct acpi_device_id *not_used) +{ + union acpi_object *out_obj; + + if (lps0_device_handle) + return 0; + + if (!(acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0)) + return 0; + + guid_parse(ACPI_LPS0_DSM_UUID, &lps0_dsm_guid); + /* Check if the _DSM is present and as expected. */ + out_obj = acpi_evaluate_dsm(adev->handle, &lps0_dsm_guid, 1, 0, NULL); + if (out_obj && out_obj->type == ACPI_TYPE_BUFFER) { + char bitmask = *(char *)out_obj->buffer.pointer; + + if ((bitmask & ACPI_S2IDLE_FUNC_MASK) == ACPI_S2IDLE_FUNC_MASK) { + lps0_dsm_func_mask = bitmask; + lps0_device_handle = adev->handle; + } + + acpi_handle_debug(adev->handle, "_DSM function mask: 0x%x\n", + bitmask); + } else { + acpi_handle_debug(adev->handle, + "_DSM function 0 evaluation failed\n"); + } + ACPI_FREE(out_obj); + return 0; +} + +static struct acpi_scan_handler lps0_handler = { + .ids = lps0_device_ids, + .attach = lps0_device_attach, +}; + static int acpi_freeze_begin(void) { acpi_scan_lock_acquire(); + s2idle_in_progress = true; return 0; } static int acpi_freeze_prepare(void) { - acpi_enable_wakeup_devices(ACPI_STATE_S0); - acpi_enable_all_wakeup_gpes(); - acpi_os_wait_events_complete(); + if (lps0_device_handle) { + acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_OFF); + acpi_sleep_run_lps0_dsm(ACPI_LPS0_ENTRY); + } else { + /* + * The configuration of GPEs is changed here to avoid spurious + * wakeups, but that should not be necessary if this is a + * "low-power S0" platform and the low-power S0 _DSM is present. + */ + acpi_enable_all_wakeup_gpes(); + acpi_os_wait_events_complete(); + } if (acpi_sci_irq_valid()) enable_irq_wake(acpi_sci_irq); @@ -675,8 +766,10 @@ static void acpi_freeze_wake(void) * case it has not been a wakeup event (the GPEs will be checked later). */ if (acpi_sci_irq_valid() && - !irqd_is_wakeup_armed(irq_get_irq_data(acpi_sci_irq))) + !irqd_is_wakeup_armed(irq_get_irq_data(acpi_sci_irq))) { pm_system_cancel_wakeup(); + s2idle_wakeup = true; + } } static void acpi_freeze_sync(void) @@ -689,19 +782,25 @@ static void acpi_freeze_sync(void) */ acpi_os_wait_events_complete(); flush_scheduled_work(); + s2idle_wakeup = false; } static void acpi_freeze_restore(void) { - acpi_disable_wakeup_devices(ACPI_STATE_S0); if (acpi_sci_irq_valid()) disable_irq_wake(acpi_sci_irq); - acpi_enable_all_runtime_gpes(); + if (lps0_device_handle) { + acpi_sleep_run_lps0_dsm(ACPI_LPS0_EXIT); + acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_ON); + } else { + acpi_enable_all_runtime_gpes(); + } } static void acpi_freeze_end(void) { + s2idle_in_progress = false; acpi_scan_lock_release(); } @@ -724,13 +823,28 @@ static void acpi_sleep_suspend_setup(void) suspend_set_ops(old_suspend_ordering ? &acpi_suspend_ops_old : &acpi_suspend_ops); + + acpi_scan_add_handler(&lps0_handler); freeze_set_ops(&acpi_freeze_ops); } #else /* !CONFIG_SUSPEND */ +#define s2idle_in_progress (false) +#define s2idle_wakeup (false) +#define lps0_device_handle (NULL) static inline void acpi_sleep_suspend_setup(void) {} #endif /* !CONFIG_SUSPEND */ +bool acpi_s2idle_wakeup(void) +{ + return s2idle_wakeup; +} + +bool acpi_sleep_no_ec_events(void) +{ + return !s2idle_in_progress || !lps0_device_handle; +} + #ifdef CONFIG_PM_SLEEP static u32 saved_bm_rld; |