Commit c35923bc authored by Alexey Starikovskiy's avatar Alexey Starikovskiy Committed by Len Brown
Browse files

ACPI: power: don't cache power resource state 



ACPI may change power resource state behind our back, so don't
keep our local copy, which may not be valid.

Signed-off-by: default avatarAlexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
parent 95b937e3

drivers/acpi/bus.c

+2 −4
Original line number Diff line number Diff line
@@ -198,10 +198,8 @@ int acpi_bus_set_power(acpi_handle handle, int state) 
		return -ENODEV;

	}

	/*

	 * Get device's current power state if it's unknown

	 * This means device power state isn't initialized or previous setting failed

	 * Get device's current power state

	 */

	if ((device->power.state == ACPI_STATE_UNKNOWN) || device->flags.force_power_state)

	acpi_bus_get_power(device->handle, &device->power.state);

	if ((state == device->power.state) && !device->flags.force_power_state) {

		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at D%d\n",

drivers/acpi/power.c

+24 −39
Original line number Diff line number Diff line
@@ -86,7 +86,6 @@ struct acpi_power_resource { 
	acpi_bus_id name;

	u32 system_level;

	u32 order;

	int state;

	struct mutex resource_lock;

	struct list_head reference;

};
@@ -128,33 +127,31 @@ acpi_power_get_context(acpi_handle handle, 
	return 0;

}



static int acpi_power_get_state(struct acpi_power_resource *resource)

static int acpi_power_get_state(struct acpi_power_resource *resource, int *state)

{

	acpi_status status = AE_OK;

	unsigned long sta = 0;





	if (!resource)

	if (!resource || !state)

		return -EINVAL;



	status = acpi_evaluate_integer(resource->device->handle, "_STA", NULL, &sta);

	if (ACPI_FAILURE(status))

		return -ENODEV;



	if (sta & 0x01)

		resource->state = ACPI_POWER_RESOURCE_STATE_ON;

	else

		resource->state = ACPI_POWER_RESOURCE_STATE_OFF;

	*state = (sta & 0x01)?ACPI_POWER_RESOURCE_STATE_ON:

			      ACPI_POWER_RESOURCE_STATE_OFF;



	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n",

			  resource->name, resource->state ? "on" : "off"));

			  resource->name, state ? "on" : "off"));



	return 0;

}



static int acpi_power_get_list_state(struct acpi_handle_list *list, int *state)

{

	int result = 0;

	int result = 0, state1;

	struct acpi_power_resource *resource = NULL;

	u32 i = 0;
@@ -168,11 +165,11 @@ static int acpi_power_get_list_state(struct acpi_handle_list *list, int *state) 
		result = acpi_power_get_context(list->handles[i], &resource);

		if (result)

			return result;

		result = acpi_power_get_state(resource);

		result = acpi_power_get_state(resource, &state1);

		if (result)

			return result;



		*state = resource->state;

		*state = state1;



		if (*state != ACPI_POWER_RESOURCE_STATE_ON)

			break;
@@ -186,7 +183,7 @@ static int acpi_power_get_list_state(struct acpi_handle_list *list, int *state) 


static int acpi_power_on(acpi_handle handle, struct acpi_device *dev)

{

	int result = 0;

	int result = 0, state;

	int found = 0;

	acpi_status status = AE_OK;

	struct acpi_power_resource *resource = NULL;
@@ -224,20 +221,14 @@ static int acpi_power_on(acpi_handle handle, struct acpi_device *dev) 
	}

	mutex_unlock(&resource->resource_lock);



	if (resource->state == ACPI_POWER_RESOURCE_STATE_ON) {

		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] already on\n",

				  resource->name));

		return 0;

	}



	status = acpi_evaluate_object(resource->device->handle, "_ON", NULL, NULL);

	if (ACPI_FAILURE(status))

		return -ENODEV;



	result = acpi_power_get_state(resource);

	result = acpi_power_get_state(resource, &state);

	if (result)

		return result;

	if (resource->state != ACPI_POWER_RESOURCE_STATE_ON)

	if (state != ACPI_POWER_RESOURCE_STATE_ON)

		return -ENOEXEC;



	/* Update the power resource's _device_ power state */
@@ -250,7 +241,7 @@ static int acpi_power_on(acpi_handle handle, struct acpi_device *dev) 


static int acpi_power_off_device(acpi_handle handle, struct acpi_device *dev)

{

	int result = 0;

	int result = 0, state;

	acpi_status status = AE_OK;

	struct acpi_power_resource *resource = NULL;

	struct list_head *node, *next;
@@ -281,20 +272,14 @@ static int acpi_power_off_device(acpi_handle handle, struct acpi_device *dev) 
	}

	mutex_unlock(&resource->resource_lock);



	if (resource->state == ACPI_POWER_RESOURCE_STATE_OFF) {

		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] already off\n",

				  resource->name));

		return 0;

	}



	status = acpi_evaluate_object(resource->device->handle, "_OFF", NULL, NULL);

	if (ACPI_FAILURE(status))

		return -ENODEV;



	result = acpi_power_get_state(resource);

	result = acpi_power_get_state(resource, &state);

	if (result)

		return result;

	if (resource->state != ACPI_POWER_RESOURCE_STATE_OFF)

	if (state != ACPI_POWER_RESOURCE_STATE_OFF)

		return -ENOEXEC;



	/* Update the power resource's _device_ power state */
@@ -494,7 +479,7 @@ static struct proc_dir_entry *acpi_power_dir; 
static int acpi_power_seq_show(struct seq_file *seq, void *offset)

{

	int count = 0;

	int result = 0;

	int result = 0, state;

	struct acpi_power_resource *resource = NULL;

	struct list_head *node, *next;

	struct acpi_power_reference *ref;
@@ -505,12 +490,12 @@ static int acpi_power_seq_show(struct seq_file *seq, void *offset) 
	if (!resource)

		goto end;



	result = acpi_power_get_state(resource);

	result = acpi_power_get_state(resource, &state);

	if (result)

		goto end;



	seq_puts(seq, "state:                   ");

	switch (resource->state) {

	switch (state) {

	case ACPI_POWER_RESOURCE_STATE_ON:

		seq_puts(seq, "on\n");

		break;
@@ -591,7 +576,7 @@ static int acpi_power_remove_fs(struct acpi_device *device) 


static int acpi_power_add(struct acpi_device *device)

{

	int result = 0;

	int result = 0, state;

	acpi_status status = AE_OK;

	struct acpi_power_resource *resource = NULL;

	union acpi_object acpi_object;
@@ -622,11 +607,11 @@ static int acpi_power_add(struct acpi_device *device) 
	resource->system_level = acpi_object.power_resource.system_level;

	resource->order = acpi_object.power_resource.resource_order;



	result = acpi_power_get_state(resource);

	result = acpi_power_get_state(resource, &state);

	if (result)

		goto end;



	switch (resource->state) {

	switch (state) {

	case ACPI_POWER_RESOURCE_STATE_ON:

		device->power.state = ACPI_STATE_D0;

		break;
@@ -643,7 +628,7 @@ static int acpi_power_add(struct acpi_device *device) 
		goto end;



	printk(KERN_INFO PREFIX "%s [%s] (%s)\n", acpi_device_name(device),

	       acpi_device_bid(device), resource->state ? "on" : "off");

	       acpi_device_bid(device), state ? "on" : "off");



      end:

	if (result)
@@ -680,7 +665,7 @@ static int acpi_power_remove(struct acpi_device *device, int type) 


static int acpi_power_resume(struct acpi_device *device)

{

	int result = 0;

	int result = 0, state;

	struct acpi_power_resource *resource = NULL;

	struct acpi_power_reference *ref;
@@ -689,12 +674,12 @@ static int acpi_power_resume(struct acpi_device *device) 


	resource = (struct acpi_power_resource *)acpi_driver_data(device);



	result = acpi_power_get_state(resource);

	result = acpi_power_get_state(resource, &state);

	if (result)

		return result;



	mutex_lock(&resource->resource_lock);

	if ((resource->state == ACPI_POWER_RESOURCE_STATE_OFF) &&

	if (state == ACPI_POWER_RESOURCE_STATE_OFF &&

	    !list_empty(&resource->reference)) {

		ref = container_of(resource->reference.next, struct acpi_power_reference, node);

		mutex_unlock(&resource->resource_lock);