From 9630bdd9b15d2f489c646d8bc04b60e53eb5ec78 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 17 Feb 2010 23:41:07 +0100 Subject: ACPI: Use GPE reference counting to support shared GPEs ACPI GPEs may map to multiple devices. The current GPE interface only provides a mechanism for enabling and disabling GPEs, making it difficult to change the state of GPEs at runtime without extensive cooperation between devices. Add an API to allow devices to indicate whether or not they want their device's GPE to be enabled for both runtime and wakeup events. Remove the old GPE type handling entirely, which gets rid of various quirks, like the implicit disabling with GPE type setting. This requires a small amount of rework in order to ensure that non-wake GPEs are enabled by default to preserve existing behaviour. Based on patches from Matthew Garrett . Signed-off-by: Matthew Garrett Signed-off-by: Rafael J. Wysocki Signed-off-by: Jesse Barnes --- drivers/acpi/sleep.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) (limited to 'drivers/acpi/sleep.c') diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c index 79d33d908b5..3bde594a997 100644 --- a/drivers/acpi/sleep.c +++ b/drivers/acpi/sleep.c @@ -745,9 +745,18 @@ int acpi_pm_device_sleep_wake(struct device *dev, bool enable) return -ENODEV; } - error = enable ? - acpi_enable_wakeup_device_power(adev, acpi_target_sleep_state) : - acpi_disable_wakeup_device_power(adev); + if (enable) { + error = acpi_enable_wakeup_device_power(adev, + acpi_target_sleep_state); + if (!error) + acpi_enable_gpe(adev->wakeup.gpe_device, + adev->wakeup.gpe_number, + ACPI_GPE_TYPE_WAKE); + } else { + acpi_disable_gpe(adev->wakeup.gpe_device, adev->wakeup.gpe_number, + ACPI_GPE_TYPE_WAKE); + error = acpi_disable_wakeup_device_power(adev); + } if (!error) dev_info(dev, "wake-up capability %s by ACPI\n", enable ? "enabled" : "disabled"); -- cgit v1.2.3-70-g09d2 From f6bb13aa1ea3bb26a4c783822347873f085b9000 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 4 Mar 2010 01:52:58 +0100 Subject: ACPI / EC / PM: Close race between EC and resume from hibernation There is a race between resume from hibernation and the EC driver that may result in restoring the hibernation image in the middle of an EC transaction in progress, which in turn may lead to unpredictable behavior of the platform. To remove that race condition, add a helpers for suspending and resuming EC transactions in a safe way to be executed by the ACPI platform hibernate pre-restore and restore cleanup callbacks. http://bugzilla.kernel.org/show_bug.cgi?id=14668 Signed-off-by: Rafael J. Wysocki Reported-and-tested-by: Maxim Levitsky Signed-off-by: Len Brown --- drivers/acpi/ec.c | 33 ++++++++++++++++++++++++++++++++- drivers/acpi/internal.h | 2 ++ drivers/acpi/sleep.c | 19 ++++++++++++++----- 3 files changed, 48 insertions(+), 6 deletions(-) (limited to 'drivers/acpi/sleep.c') diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c index d6471bb6852..19f93e11422 100644 --- a/drivers/acpi/ec.c +++ b/drivers/acpi/ec.c @@ -76,8 +76,9 @@ enum ec_command { enum { EC_FLAGS_QUERY_PENDING, /* Query is pending */ EC_FLAGS_GPE_STORM, /* GPE storm detected */ - EC_FLAGS_HANDLERS_INSTALLED /* Handlers for GPE and + EC_FLAGS_HANDLERS_INSTALLED, /* Handlers for GPE and * OpReg are installed */ + EC_FLAGS_FROZEN, /* Transactions are suspended */ }; /* If we find an EC via the ECDT, we need to keep a ptr to its context */ @@ -291,6 +292,10 @@ static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) if (t->rdata) memset(t->rdata, 0, t->rlen); mutex_lock(&ec->lock); + if (test_bit(EC_FLAGS_FROZEN, &ec->flags)) { + status = -EINVAL; + goto unlock; + } if (ec->global_lock) { status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk); if (ACPI_FAILURE(status)) { @@ -445,6 +450,32 @@ int ec_transaction(u8 command, EXPORT_SYMBOL(ec_transaction); +void acpi_ec_suspend_transactions(void) +{ + struct acpi_ec *ec = first_ec; + + if (!ec) + return; + + mutex_lock(&ec->lock); + /* Prevent transactions from being carried out */ + set_bit(EC_FLAGS_FROZEN, &ec->flags); + mutex_unlock(&ec->lock); +} + +void acpi_ec_resume_transactions(void) +{ + struct acpi_ec *ec = first_ec; + + if (!ec) + return; + + mutex_lock(&ec->lock); + /* Allow transactions to be carried out again */ + clear_bit(EC_FLAGS_FROZEN, &ec->flags); + mutex_unlock(&ec->lock); +} + static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data) { int result; diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h index cb28e0502ac..78742460f1f 100644 --- a/drivers/acpi/internal.h +++ b/drivers/acpi/internal.h @@ -51,6 +51,8 @@ void acpi_early_processor_set_pdc(void); int acpi_ec_init(void); int acpi_ec_ecdt_probe(void); int acpi_boot_ec_enable(void); +void acpi_ec_suspend_transactions(void); +void acpi_ec_resume_transactions(void); /*-------------------------------------------------------------------------- Suspend/Resume diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c index 79d33d908b5..f01f8e84fd3 100644 --- a/drivers/acpi/sleep.c +++ b/drivers/acpi/sleep.c @@ -552,8 +552,17 @@ static void acpi_hibernation_leave(void) hibernate_nvs_restore(); } -static void acpi_pm_enable_gpes(void) +static int acpi_pm_pre_restore(void) { + acpi_disable_all_gpes(); + acpi_os_wait_events_complete(NULL); + acpi_ec_suspend_transactions(); + return 0; +} + +static void acpi_pm_restore_cleanup(void) +{ + acpi_ec_resume_transactions(); acpi_enable_all_runtime_gpes(); } @@ -565,8 +574,8 @@ static struct platform_hibernation_ops acpi_hibernation_ops = { .prepare = acpi_pm_prepare, .enter = acpi_hibernation_enter, .leave = acpi_hibernation_leave, - .pre_restore = acpi_pm_disable_gpes, - .restore_cleanup = acpi_pm_enable_gpes, + .pre_restore = acpi_pm_pre_restore, + .restore_cleanup = acpi_pm_restore_cleanup, }; /** @@ -618,8 +627,8 @@ static struct platform_hibernation_ops acpi_hibernation_ops_old = { .prepare = acpi_pm_disable_gpes, .enter = acpi_hibernation_enter, .leave = acpi_hibernation_leave, - .pre_restore = acpi_pm_disable_gpes, - .restore_cleanup = acpi_pm_enable_gpes, + .pre_restore = acpi_pm_pre_restore, + .restore_cleanup = acpi_pm_restore_cleanup, .recover = acpi_pm_finish, }; #endif /* CONFIG_HIBERNATION */ -- cgit v1.2.3-70-g09d2