From bc9b6407bd6df3ab7189e5622816bbc11ae9d2d8 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 17 Jan 2013 14:11:05 +0100 Subject: ACPI / PM: Rework the handling of devices depending on power resources Commit 0090def6 (ACPI: Add interface to register/unregister device to/from power resources) made it possible to indicate to the ACPI core that if the given device depends on any power resources, then it should be resumed as soon as all of the power resources required by it to transition to the D0 power state have been turned on. Unfortunately, however, this was a mistake, because all devices depending on power resources should be treated this way (i.e. they should be resumed when all power resources required by their D0 state have been turned on) and for the majority of those devices the ACPI core can figure out by itself which (physical) devices depend on what power resources. For this reason, replace the code added by commit 0090def6 with a new, much more straightforward, mechanism that will be used internally by the ACPI core and remove all references to that code from kernel subsystems using ACPI. For the cases when there are (physical) devices that should be resumed whenever a not directly related ACPI device node goes into D0 as a result of power resources configuration changes, like in the SATA case, add two new routines, acpi_dev_pm_add_dependent() and acpi_dev_pm_remove_dependent(), allowing subsystems to manage such dependencies. Convert the SATA subsystem to use the new functions accordingly. Signed-off-by: Rafael J. Wysocki --- drivers/acpi/device_pm.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) (limited to 'drivers/acpi/device_pm.c') diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c index 995019063f6..8be4b29e38a 100644 --- a/drivers/acpi/device_pm.c +++ b/drivers/acpi/device_pm.c @@ -665,3 +665,59 @@ void acpi_dev_pm_detach(struct device *dev, bool power_off) } } EXPORT_SYMBOL_GPL(acpi_dev_pm_detach); + +/** + * acpi_dev_pm_add_dependent - Add physical device depending for PM. + * @handle: Handle of ACPI device node. + * @depdev: Device depending on that node for PM. + */ +void acpi_dev_pm_add_dependent(acpi_handle handle, struct device *depdev) +{ + struct acpi_device_physical_node *dep; + struct acpi_device *adev; + + if (!depdev || acpi_bus_get_device(handle, &adev)) + return; + + mutex_lock(&adev->physical_node_lock); + + list_for_each_entry(dep, &adev->power_dependent, node) + if (dep->dev == depdev) + goto out; + + dep = kzalloc(sizeof(*dep), GFP_KERNEL); + if (dep) { + dep->dev = depdev; + list_add_tail(&dep->node, &adev->power_dependent); + } + + out: + mutex_unlock(&adev->physical_node_lock); +} +EXPORT_SYMBOL_GPL(acpi_dev_pm_add_dependent); + +/** + * acpi_dev_pm_remove_dependent - Remove physical device depending for PM. + * @handle: Handle of ACPI device node. + * @depdev: Device depending on that node for PM. + */ +void acpi_dev_pm_remove_dependent(acpi_handle handle, struct device *depdev) +{ + struct acpi_device_physical_node *dep; + struct acpi_device *adev; + + if (!depdev || acpi_bus_get_device(handle, &adev)) + return; + + mutex_lock(&adev->physical_node_lock); + + list_for_each_entry(dep, &adev->power_dependent, node) + if (dep->dev == depdev) { + list_del(&dep->node); + kfree(dep); + break; + } + + mutex_unlock(&adev->physical_node_lock); +} +EXPORT_SYMBOL_GPL(acpi_dev_pm_remove_dependent); -- cgit v1.2.3-70-g09d2 From 9ce4e607111764673f7a59d7bc87a16ade5c7bba Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 17 Jan 2013 14:11:08 +0100 Subject: ACPI / PM: Move device power management functions to device_pm.c Move ACPI device power management functions from drivers/acpi/bus.c to drivers/acpi/device_pm.c. Signed-off-by: Rafael J. Wysocki --- drivers/acpi/bus.c | 293 ----------------------------------------------- drivers/acpi/device_pm.c | 288 ++++++++++++++++++++++++++++++++++++++++++++++ drivers/acpi/internal.h | 1 - include/acpi/acpi_bus.h | 38 ++++++ 4 files changed, 326 insertions(+), 294 deletions(-) (limited to 'drivers/acpi/device_pm.c') diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c index 6c9b16c1666..01708a16536 100644 --- a/drivers/acpi/bus.c +++ b/drivers/acpi/bus.c @@ -178,299 +178,6 @@ int acpi_bus_get_private_data(acpi_handle handle, void **data) } EXPORT_SYMBOL(acpi_bus_get_private_data); -/* -------------------------------------------------------------------------- - Power Management - -------------------------------------------------------------------------- */ - -/** - * acpi_power_state_string - String representation of ACPI device power state. - * @state: ACPI device power state to return the string representation of. - */ -const char *acpi_power_state_string(int state) -{ - switch (state) { - case ACPI_STATE_D0: - return "D0"; - case ACPI_STATE_D1: - return "D1"; - case ACPI_STATE_D2: - return "D2"; - case ACPI_STATE_D3_HOT: - return "D3hot"; - case ACPI_STATE_D3_COLD: - return "D3"; - default: - return "(unknown)"; - } -} - -/** - * acpi_device_get_power - Get power state of an ACPI device. - * @device: Device to get the power state of. - * @state: Place to store the power state of the device. - * - * This function does not update the device's power.state field, but it may - * update its parent's power.state field (when the parent's power state is - * unknown and the device's power state turns out to be D0). - */ -int acpi_device_get_power(struct acpi_device *device, int *state) -{ - int result = ACPI_STATE_UNKNOWN; - - if (!device || !state) - return -EINVAL; - - if (!device->flags.power_manageable) { - /* TBD: Non-recursive algorithm for walking up hierarchy. */ - *state = device->parent ? - device->parent->power.state : ACPI_STATE_D0; - goto out; - } - - /* - * Get the device's power state either directly (via _PSC) or - * indirectly (via power resources). - */ - if (device->power.flags.explicit_get) { - unsigned long long psc; - acpi_status status = acpi_evaluate_integer(device->handle, - "_PSC", NULL, &psc); - if (ACPI_FAILURE(status)) - return -ENODEV; - - result = psc; - } - /* The test below covers ACPI_STATE_UNKNOWN too. */ - if (result <= ACPI_STATE_D2) { - ; /* Do nothing. */ - } else if (device->power.flags.power_resources) { - int error = acpi_power_get_inferred_state(device, &result); - if (error) - return error; - } else if (result == ACPI_STATE_D3_HOT) { - result = ACPI_STATE_D3; - } - - /* - * If we were unsure about the device parent's power state up to this - * point, the fact that the device is in D0 implies that the parent has - * to be in D0 too. - */ - if (device->parent && device->parent->power.state == ACPI_STATE_UNKNOWN - && result == ACPI_STATE_D0) - device->parent->power.state = ACPI_STATE_D0; - - *state = result; - - out: - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n", - device->pnp.bus_id, acpi_power_state_string(*state))); - - return 0; -} - - -/** - * acpi_device_set_power - Set power state of an ACPI device. - * @device: Device to set the power state of. - * @state: New power state to set. - * - * Callers must ensure that the device is power manageable before using this - * function. - */ -int acpi_device_set_power(struct acpi_device *device, int state) -{ - int result = 0; - acpi_status status = AE_OK; - char object_name[5] = { '_', 'P', 'S', '0' + state, '\0' }; - bool cut_power = false; - - if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD)) - return -EINVAL; - - /* Make sure this is a valid target state */ - - if (state == device->power.state) { - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at %s\n", - acpi_power_state_string(state))); - return 0; - } - - if (!device->power.states[state].flags.valid) { - printk(KERN_WARNING PREFIX "Device does not support %s\n", - acpi_power_state_string(state)); - return -ENODEV; - } - if (device->parent && (state < device->parent->power.state)) { - printk(KERN_WARNING PREFIX - "Cannot set device to a higher-powered" - " state than parent\n"); - return -ENODEV; - } - - /* For D3cold we should first transition into D3hot. */ - if (state == ACPI_STATE_D3_COLD - && device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible) { - state = ACPI_STATE_D3_HOT; - object_name[3] = '3'; - cut_power = true; - } - - /* - * Transition Power - * ---------------- - * On transitions to a high-powered state we first apply power (via - * power resources) then evalute _PSx. Conversly for transitions to - * a lower-powered state. - */ - if (state < device->power.state) { - if (device->power.state >= ACPI_STATE_D3_HOT && - state != ACPI_STATE_D0) { - printk(KERN_WARNING PREFIX - "Cannot transition to non-D0 state from D3\n"); - return -ENODEV; - } - if (device->power.flags.power_resources) { - result = acpi_power_transition(device, state); - if (result) - goto end; - } - if (device->power.states[state].flags.explicit_set) { - status = acpi_evaluate_object(device->handle, - object_name, NULL, NULL); - if (ACPI_FAILURE(status)) { - result = -ENODEV; - goto end; - } - } - } else { - if (device->power.states[state].flags.explicit_set) { - status = acpi_evaluate_object(device->handle, - object_name, NULL, NULL); - if (ACPI_FAILURE(status)) { - result = -ENODEV; - goto end; - } - } - if (device->power.flags.power_resources) { - result = acpi_power_transition(device, state); - if (result) - goto end; - } - } - - if (cut_power) - result = acpi_power_transition(device, ACPI_STATE_D3_COLD); - - end: - if (result) - printk(KERN_WARNING PREFIX - "Device [%s] failed to transition to %s\n", - device->pnp.bus_id, - acpi_power_state_string(state)); - else { - device->power.state = state; - ACPI_DEBUG_PRINT((ACPI_DB_INFO, - "Device [%s] transitioned to %s\n", - device->pnp.bus_id, - acpi_power_state_string(state))); - } - - return result; -} -EXPORT_SYMBOL(acpi_device_set_power); - - -int acpi_bus_set_power(acpi_handle handle, int state) -{ - struct acpi_device *device; - int result; - - result = acpi_bus_get_device(handle, &device); - if (result) - return result; - - if (!device->flags.power_manageable) { - ACPI_DEBUG_PRINT((ACPI_DB_INFO, - "Device [%s] is not power manageable\n", - dev_name(&device->dev))); - return -ENODEV; - } - - return acpi_device_set_power(device, state); -} -EXPORT_SYMBOL(acpi_bus_set_power); - - -int acpi_bus_init_power(struct acpi_device *device) -{ - int state; - int result; - - if (!device) - return -EINVAL; - - device->power.state = ACPI_STATE_UNKNOWN; - - result = acpi_device_get_power(device, &state); - if (result) - return result; - - if (device->power.flags.power_resources) - result = acpi_power_on_resources(device, state); - - if (!result) - device->power.state = state; - - return result; -} - - -int acpi_bus_update_power(acpi_handle handle, int *state_p) -{ - struct acpi_device *device; - int state; - int result; - - result = acpi_bus_get_device(handle, &device); - if (result) - return result; - - result = acpi_device_get_power(device, &state); - if (result) - return result; - - result = acpi_device_set_power(device, state); - if (!result && state_p) - *state_p = state; - - return result; -} -EXPORT_SYMBOL_GPL(acpi_bus_update_power); - - -bool acpi_bus_power_manageable(acpi_handle handle) -{ - struct acpi_device *device; - int result; - - result = acpi_bus_get_device(handle, &device); - return result ? false : device->flags.power_manageable; -} - -EXPORT_SYMBOL(acpi_bus_power_manageable); - -bool acpi_bus_can_wakeup(acpi_handle handle) -{ - struct acpi_device *device; - int result; - - result = acpi_bus_get_device(handle, &device); - return result ? false : device->wakeup.flags.valid; -} - -EXPORT_SYMBOL(acpi_bus_can_wakeup); - static void acpi_print_osc_error(acpi_handle handle, struct acpi_osc_context *context, char *error) { diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c index 8be4b29e38a..8bca7465c78 100644 --- a/drivers/acpi/device_pm.c +++ b/drivers/acpi/device_pm.c @@ -30,6 +30,12 @@ #include #include +#include + +#include "internal.h" + +#define _COMPONENT ACPI_POWER_COMPONENT +ACPI_MODULE_NAME("device_pm"); static DEFINE_MUTEX(acpi_pm_notifier_lock); @@ -93,6 +99,288 @@ acpi_status acpi_remove_pm_notifier(struct acpi_device *adev, return status; } +/** + * acpi_power_state_string - String representation of ACPI device power state. + * @state: ACPI device power state to return the string representation of. + */ +const char *acpi_power_state_string(int state) +{ + switch (state) { + case ACPI_STATE_D0: + return "D0"; + case ACPI_STATE_D1: + return "D1"; + case ACPI_STATE_D2: + return "D2"; + case ACPI_STATE_D3_HOT: + return "D3hot"; + case ACPI_STATE_D3_COLD: + return "D3"; + default: + return "(unknown)"; + } +} + +/** + * acpi_device_get_power - Get power state of an ACPI device. + * @device: Device to get the power state of. + * @state: Place to store the power state of the device. + * + * This function does not update the device's power.state field, but it may + * update its parent's power.state field (when the parent's power state is + * unknown and the device's power state turns out to be D0). + */ +int acpi_device_get_power(struct acpi_device *device, int *state) +{ + int result = ACPI_STATE_UNKNOWN; + + if (!device || !state) + return -EINVAL; + + if (!device->flags.power_manageable) { + /* TBD: Non-recursive algorithm for walking up hierarchy. */ + *state = device->parent ? + device->parent->power.state : ACPI_STATE_D0; + goto out; + } + + /* + * Get the device's power state either directly (via _PSC) or + * indirectly (via power resources). + */ + if (device->power.flags.explicit_get) { + unsigned long long psc; + acpi_status status = acpi_evaluate_integer(device->handle, + "_PSC", NULL, &psc); + if (ACPI_FAILURE(status)) + return -ENODEV; + + result = psc; + } + /* The test below covers ACPI_STATE_UNKNOWN too. */ + if (result <= ACPI_STATE_D2) { + ; /* Do nothing. */ + } else if (device->power.flags.power_resources) { + int error = acpi_power_get_inferred_state(device, &result); + if (error) + return error; + } else if (result == ACPI_STATE_D3_HOT) { + result = ACPI_STATE_D3; + } + + /* + * If we were unsure about the device parent's power state up to this + * point, the fact that the device is in D0 implies that the parent has + * to be in D0 too. + */ + if (device->parent && device->parent->power.state == ACPI_STATE_UNKNOWN + && result == ACPI_STATE_D0) + device->parent->power.state = ACPI_STATE_D0; + + *state = result; + + out: + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n", + device->pnp.bus_id, acpi_power_state_string(*state))); + + return 0; +} + +/** + * acpi_device_set_power - Set power state of an ACPI device. + * @device: Device to set the power state of. + * @state: New power state to set. + * + * Callers must ensure that the device is power manageable before using this + * function. + */ +int acpi_device_set_power(struct acpi_device *device, int state) +{ + int result = 0; + acpi_status status = AE_OK; + char object_name[5] = { '_', 'P', 'S', '0' + state, '\0' }; + bool cut_power = false; + + if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD)) + return -EINVAL; + + /* Make sure this is a valid target state */ + + if (state == device->power.state) { + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at %s\n", + acpi_power_state_string(state))); + return 0; + } + + if (!device->power.states[state].flags.valid) { + printk(KERN_WARNING PREFIX "Device does not support %s\n", + acpi_power_state_string(state)); + return -ENODEV; + } + if (device->parent && (state < device->parent->power.state)) { + printk(KERN_WARNING PREFIX + "Cannot set device to a higher-powered" + " state than parent\n"); + return -ENODEV; + } + + /* For D3cold we should first transition into D3hot. */ + if (state == ACPI_STATE_D3_COLD + && device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible) { + state = ACPI_STATE_D3_HOT; + object_name[3] = '3'; + cut_power = true; + } + + /* + * Transition Power + * ---------------- + * On transitions to a high-powered state we first apply power (via + * power resources) then evalute _PSx. Conversly for transitions to + * a lower-powered state. + */ + if (state < device->power.state) { + if (device->power.state >= ACPI_STATE_D3_HOT && + state != ACPI_STATE_D0) { + printk(KERN_WARNING PREFIX + "Cannot transition to non-D0 state from D3\n"); + return -ENODEV; + } + if (device->power.flags.power_resources) { + result = acpi_power_transition(device, state); + if (result) + goto end; + } + if (device->power.states[state].flags.explicit_set) { + status = acpi_evaluate_object(device->handle, + object_name, NULL, NULL); + if (ACPI_FAILURE(status)) { + result = -ENODEV; + goto end; + } + } + } else { + if (device->power.states[state].flags.explicit_set) { + status = acpi_evaluate_object(device->handle, + object_name, NULL, NULL); + if (ACPI_FAILURE(status)) { + result = -ENODEV; + goto end; + } + } + if (device->power.flags.power_resources) { + result = acpi_power_transition(device, state); + if (result) + goto end; + } + } + + if (cut_power) + result = acpi_power_transition(device, ACPI_STATE_D3_COLD); + + end: + if (result) + printk(KERN_WARNING PREFIX + "Device [%s] failed to transition to %s\n", + device->pnp.bus_id, + acpi_power_state_string(state)); + else { + device->power.state = state; + ACPI_DEBUG_PRINT((ACPI_DB_INFO, + "Device [%s] transitioned to %s\n", + device->pnp.bus_id, + acpi_power_state_string(state))); + } + + return result; +} +EXPORT_SYMBOL(acpi_device_set_power); + +int acpi_bus_set_power(acpi_handle handle, int state) +{ + struct acpi_device *device; + int result; + + result = acpi_bus_get_device(handle, &device); + if (result) + return result; + + if (!device->flags.power_manageable) { + ACPI_DEBUG_PRINT((ACPI_DB_INFO, + "Device [%s] is not power manageable\n", + dev_name(&device->dev))); + return -ENODEV; + } + + return acpi_device_set_power(device, state); +} +EXPORT_SYMBOL(acpi_bus_set_power); + +int acpi_bus_init_power(struct acpi_device *device) +{ + int state; + int result; + + if (!device) + return -EINVAL; + + device->power.state = ACPI_STATE_UNKNOWN; + + result = acpi_device_get_power(device, &state); + if (result) + return result; + + if (device->power.flags.power_resources) + result = acpi_power_on_resources(device, state); + + if (!result) + device->power.state = state; + + return result; +} + +int acpi_bus_update_power(acpi_handle handle, int *state_p) +{ + struct acpi_device *device; + int state; + int result; + + result = acpi_bus_get_device(handle, &device); + if (result) + return result; + + result = acpi_device_get_power(device, &state); + if (result) + return result; + + result = acpi_device_set_power(device, state); + if (!result && state_p) + *state_p = state; + + return result; +} +EXPORT_SYMBOL_GPL(acpi_bus_update_power); + +bool acpi_bus_power_manageable(acpi_handle handle) +{ + struct acpi_device *device; + int result; + + result = acpi_bus_get_device(handle, &device); + return result ? false : device->flags.power_manageable; +} +EXPORT_SYMBOL(acpi_bus_power_manageable); + +bool acpi_bus_can_wakeup(acpi_handle handle) +{ + struct acpi_device *device; + int result; + + result = acpi_bus_get_device(handle, &device); + return result ? false : device->wakeup.flags.valid; +} +EXPORT_SYMBOL(acpi_bus_can_wakeup); + /** * acpi_device_power_state - Get preferred power state of ACPI device. * @dev: Device whose preferred target power state to return. diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h index 07f61dbd813..1f004f35bc6 100644 --- a/drivers/acpi/internal.h +++ b/drivers/acpi/internal.h @@ -61,7 +61,6 @@ int acpi_device_sleep_wake(struct acpi_device *dev, int acpi_power_get_inferred_state(struct acpi_device *device, int *state); int acpi_power_on_resources(struct acpi_device *device, int state); int acpi_power_transition(struct acpi_device *device, int state); -int acpi_bus_init_power(struct acpi_device *device); int acpi_wakeup_device_init(void); void acpi_early_processor_set_pdc(void); diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h index 71eceb99d41..fca1b9cb27d 100644 --- a/include/acpi/acpi_bus.h +++ b/include/acpi/acpi_bus.h @@ -330,13 +330,51 @@ void acpi_bus_data_handler(acpi_handle handle, void *context); acpi_status acpi_bus_get_status_handle(acpi_handle handle, unsigned long long *sta); int acpi_bus_get_status(struct acpi_device *device); + +#ifdef CONFIG_PM int acpi_bus_set_power(acpi_handle handle, int state); const char *acpi_power_state_string(int state); int acpi_device_get_power(struct acpi_device *device, int *state); int acpi_device_set_power(struct acpi_device *device, int state); +int acpi_bus_init_power(struct acpi_device *device); int acpi_bus_update_power(acpi_handle handle, int *state_p); bool acpi_bus_power_manageable(acpi_handle handle); bool acpi_bus_can_wakeup(acpi_handle handle); +#else /* !CONFIG_PM */ +static inline int acpi_bus_set_power(acpi_handle handle, int state) +{ + return 0; +} +static inline const char *acpi_power_state_string(int state) +{ + return "D0"; +} +static inline int acpi_device_get_power(struct acpi_device *device, int *state) +{ + return 0; +} +static inline int acpi_device_set_power(struct acpi_device *device, int state) +{ + return 0; +} +static inline int acpi_bus_init_power(struct acpi_device *device) +{ + return 0; +} +static inline int acpi_bus_update_power(acpi_handle handle, int *state_p) +{ + return 0; +} +static inline bool acpi_bus_power_manageable(acpi_handle handle) +{ + return false; +} +static inline bool acpi_bus_can_wakeup(acpi_handle handle) +{ + return false; +} +#endif /* !CONFIG_PM */ + #ifdef CONFIG_ACPI_PROC_EVENT int acpi_bus_generate_proc_event(struct acpi_device *device, u8 type, int data); int acpi_bus_generate_proc_event4(const char *class, const char *bid, u8 type, int data); -- cgit v1.2.3-70-g09d2 From 4d56410b955c3f4f7651a088e1c7a19a0d5d4e4c Mon Sep 17 00:00:00 2001 From: Mika Westerberg Date: Mon, 14 Jan 2013 20:13:37 +0000 Subject: ACPI / PM: remove leading whitespace from #ifdef It is there probably due to an accident, get rid of it so that the format is consistent across the file. Signed-off-by: Mika Westerberg Signed-off-by: Rafael J. Wysocki --- drivers/acpi/device_pm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/acpi/device_pm.c') diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c index 8bca7465c78..43116cdbabf 100644 --- a/drivers/acpi/device_pm.c +++ b/drivers/acpi/device_pm.c @@ -592,7 +592,7 @@ static inline void acpi_wakeup_device(acpi_handle handle, u32 event, void *context) {} #endif /* CONFIG_PM_RUNTIME */ - #ifdef CONFIG_PM_SLEEP +#ifdef CONFIG_PM_SLEEP /** * __acpi_device_sleep_wake - Enable or disable device to wake up the system. * @dev: Device to enable/desible to wake up the system. -- cgit v1.2.3-70-g09d2 From a2367807b8d2c0aca5afb92fead2537dcd3d10b0 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 22 Jan 2013 12:54:38 +0100 Subject: ACPI / PM: Make acpi_bus_init_power() more robust The ACPI specification requires the _PSC method to be present under a device object if its power state cannot be inferred from the states of power resources used by it (ACPI 5, Section 7.6.2). However, it also requires that (for power states D0-D2 and D3hot) if the _PSn (n = 0, 1, 2, 3) method is present under the device object, it also must be executed after the power resources have been set appropriately for the device to go into power state Dn (D3 means D3hot in this case). Thus it is not clear from the specification whether or not the _PSn method should be executed if the initial configuraion of power resources used by the device indicates power state Dn and the _PSC method is not present. The current implementation of acpi_bus_init_power() is based on the assumption that it should not be necessary to execute _PSn in the above situation, but experience shows that in fact that assumption need not be satisfied. For this reason, make acpi_bus_init_power() always execute _PSn if the initial configuration of device power resources indicates power state Dn. Reported-and-tested-by: Mika Westerberg Signed-off-by: Rafael J. Wysocki --- drivers/acpi/device_pm.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) (limited to 'drivers/acpi/device_pm.c') diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c index 43116cdbabf..c87853f583d 100644 --- a/drivers/acpi/device_pm.c +++ b/drivers/acpi/device_pm.c @@ -330,13 +330,23 @@ int acpi_bus_init_power(struct acpi_device *device) if (result) return result; - if (device->power.flags.power_resources) + if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) { result = acpi_power_on_resources(device, state); + if (result) + return result; - if (!result) - device->power.state = state; + if (device->power.states[state].flags.explicit_set) { + char method[5] = { '_', 'P', 'S', '0' + state, '\0' }; + acpi_status status; - return result; + status = acpi_evaluate_object(device->handle, method, + NULL, NULL); + if (ACPI_FAILURE(status)) + return -ENODEV; + } + } + device->power.state = state; + return 0; } int acpi_bus_update_power(acpi_handle handle, int *state_p) -- cgit v1.2.3-70-g09d2 From 9c0f45e388fb9f9003ea22f98b84ffbab65ba554 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 22 Jan 2013 12:55:52 +0100 Subject: ACPI / PM: Introduce helper for executing _PSn methods To reduce code duplication between acpi_device_set_power() and acpi_bus_init_power(), introduce a new helper function for executing ACPI devices' _PSn (n = 0..3) methods, acpi_dev_pm_explicit_set(). Signed-off-by: Rafael J. Wysocki --- drivers/acpi/device_pm.c | 51 ++++++++++++++++++++++-------------------------- 1 file changed, 23 insertions(+), 28 deletions(-) (limited to 'drivers/acpi/device_pm.c') diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c index c87853f583d..d7f3908c2e8 100644 --- a/drivers/acpi/device_pm.c +++ b/drivers/acpi/device_pm.c @@ -186,6 +186,19 @@ int acpi_device_get_power(struct acpi_device *device, int *state) return 0; } +static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state) +{ + if (adev->power.states[state].flags.explicit_set) { + char method[5] = { '_', 'P', 'S', '0' + state, '\0' }; + acpi_status status; + + status = acpi_evaluate_object(adev->handle, method, NULL, NULL); + if (ACPI_FAILURE(status)) + return -ENODEV; + } + return 0; +} + /** * acpi_device_set_power - Set power state of an ACPI device. * @device: Device to set the power state of. @@ -197,8 +210,6 @@ int acpi_device_get_power(struct acpi_device *device, int *state) int acpi_device_set_power(struct acpi_device *device, int state) { int result = 0; - acpi_status status = AE_OK; - char object_name[5] = { '_', 'P', 'S', '0' + state, '\0' }; bool cut_power = false; if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD)) @@ -228,7 +239,6 @@ int acpi_device_set_power(struct acpi_device *device, int state) if (state == ACPI_STATE_D3_COLD && device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible) { state = ACPI_STATE_D3_HOT; - object_name[3] = '3'; cut_power = true; } @@ -251,23 +261,14 @@ int acpi_device_set_power(struct acpi_device *device, int state) if (result) goto end; } - if (device->power.states[state].flags.explicit_set) { - status = acpi_evaluate_object(device->handle, - object_name, NULL, NULL); - if (ACPI_FAILURE(status)) { - result = -ENODEV; - goto end; - } - } + result = acpi_dev_pm_explicit_set(device, state); + if (result) + goto end; } else { - if (device->power.states[state].flags.explicit_set) { - status = acpi_evaluate_object(device->handle, - object_name, NULL, NULL); - if (ACPI_FAILURE(status)) { - result = -ENODEV; - goto end; - } - } + result = acpi_dev_pm_explicit_set(device, state); + if (result) + goto end; + if (device->power.flags.power_resources) { result = acpi_power_transition(device, state); if (result) @@ -335,15 +336,9 @@ int acpi_bus_init_power(struct acpi_device *device) if (result) return result; - if (device->power.states[state].flags.explicit_set) { - char method[5] = { '_', 'P', 'S', '0' + state, '\0' }; - acpi_status status; - - status = acpi_evaluate_object(device->handle, method, - NULL, NULL); - if (ACPI_FAILURE(status)) - return -ENODEV; - } + result = acpi_dev_pm_explicit_set(device, state); + if (result) + return result; } device->power.state = state; return 0; -- cgit v1.2.3-70-g09d2 From e78adb7595a9d585c60a7497345cb6eaeaaacefb Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 22 Jan 2013 12:56:04 +0100 Subject: ACPI / PM: Always evaluate _PSn after setting power resources The ACPI specitication (ACPI 5, Sections 7.2.8 - 7.2.11) requires that the _PSn (n = 0..3) method, if present, be executed after the power resources for the given device power state have been set appropriately. However, acpi_device_set_power() does that only if the new power state is going to be higher-power (lower-number) than the power state the device is in already. Otherwise, the ordering is reverse to protect against situations in which _PSn might access device registers unavailable after configuring the power resources for power state Dn (D3 meaning D3hot). Such situations are very unlikely to happen, though, and _PSn may actually be implemented with the assumption that power resources have been configured for power state Dn in advance, so change the code to follow the specification literally. This change was previously porposed in a different form by Lv Zheng. Signed-off-by: Rafael J. Wysocki --- drivers/acpi/device_pm.c | 46 +++++++++++++++++----------------------------- 1 file changed, 17 insertions(+), 29 deletions(-) (limited to 'drivers/acpi/device_pm.c') diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c index d7f3908c2e8..2ce07cee043 100644 --- a/drivers/acpi/device_pm.c +++ b/drivers/acpi/device_pm.c @@ -242,50 +242,38 @@ int acpi_device_set_power(struct acpi_device *device, int state) cut_power = true; } + if (state < device->power.state && state != ACPI_STATE_D0 + && device->power.state >= ACPI_STATE_D3_HOT) { + printk(KERN_WARNING PREFIX + "Cannot transition to non-D0 state from D3\n"); + return -ENODEV; + } + /* * Transition Power * ---------------- - * On transitions to a high-powered state we first apply power (via - * power resources) then evalute _PSx. Conversly for transitions to - * a lower-powered state. + * In accordance with the ACPI specification first apply power (via + * power resources) and then evalute _PSx. */ - if (state < device->power.state) { - if (device->power.state >= ACPI_STATE_D3_HOT && - state != ACPI_STATE_D0) { - printk(KERN_WARNING PREFIX - "Cannot transition to non-D0 state from D3\n"); - return -ENODEV; - } - if (device->power.flags.power_resources) { - result = acpi_power_transition(device, state); - if (result) - goto end; - } - result = acpi_dev_pm_explicit_set(device, state); + if (device->power.flags.power_resources) { + result = acpi_power_transition(device, state); if (result) goto end; - } else { - result = acpi_dev_pm_explicit_set(device, state); - if (result) - goto end; - - if (device->power.flags.power_resources) { - result = acpi_power_transition(device, state); - if (result) - goto end; - } } + result = acpi_dev_pm_explicit_set(device, state); + if (result) + goto end; if (cut_power) result = acpi_power_transition(device, ACPI_STATE_D3_COLD); - end: - if (result) + end: + if (result) { printk(KERN_WARNING PREFIX "Device [%s] failed to transition to %s\n", device->pnp.bus_id, acpi_power_state_string(state)); - else { + } else { device->power.state = state; ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] transitioned to %s\n", -- cgit v1.2.3-70-g09d2 From 898fee4f6ed52b5b5dd159b221d2ad7ce40ae2dd Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 22 Jan 2013 12:56:26 +0100 Subject: ACPI / PM: Use string "D3cold" to represent ACPI_STATE_D3_COLD Make acpi_power_state_string() return "D3cold" as the string representation of ACPI power state D3cold instead of "D3" returned currently, which is confusing. Signed-off-by: Rafael J. Wysocki --- drivers/acpi/device_pm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/acpi/device_pm.c') diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c index 2ce07cee043..61ae99b09f1 100644 --- a/drivers/acpi/device_pm.c +++ b/drivers/acpi/device_pm.c @@ -115,7 +115,7 @@ const char *acpi_power_state_string(int state) case ACPI_STATE_D3_HOT: return "D3hot"; case ACPI_STATE_D3_COLD: - return "D3"; + return "D3cold"; default: return "(unknown)"; } -- cgit v1.2.3-70-g09d2 From e5656271b0221a53e9f74856385112fdcec0dd60 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 22 Jan 2013 12:56:35 +0100 Subject: ACPI / PM: Fix device power state value after transitions to D3cold When a transition to the D3cold power state is requested, acpi_device_set_power() first carries out a transition to D3hot and then turns off the device's power resources. However, it fails to update the device's power.state field appropriately and D3hot is stored in it as a result. Fix this, but make sure that the device's power state will be D3hot if its power resources cannot be turned off in the final step. Signed-off-by: Rafael J. Wysocki --- drivers/acpi/device_pm.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'drivers/acpi/device_pm.c') diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c index 61ae99b09f1..4cbc9505b36 100644 --- a/drivers/acpi/device_pm.c +++ b/drivers/acpi/device_pm.c @@ -264,8 +264,11 @@ int acpi_device_set_power(struct acpi_device *device, int state) if (result) goto end; - if (cut_power) - result = acpi_power_transition(device, ACPI_STATE_D3_COLD); + if (cut_power) { + device->power.state = state; + state = ACPI_STATE_D3_COLD; + result = acpi_power_transition(device, state); + } end: if (result) { -- cgit v1.2.3-70-g09d2