diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c index 9bd1b6044b5..95fedbdf4fb 100644 --- a/drivers/acpi/power.c +++ b/drivers/acpi/power.c @@ -266,6 +266,35 @@ static int acpi_power_off_device(acpi_handle handle) return result; } +static void __acpi_power_off_list(struct acpi_handle_list *list, int num_res) +{ + int i; + + for (i = num_res - 1; i >= 0 ; i--) + acpi_power_off_device(list->handles[i]); +} + +static void acpi_power_off_list(struct acpi_handle_list *list) +{ + __acpi_power_off_list(list, list->count); +} + +static int acpi_power_on_list(struct acpi_handle_list *list) +{ + int result = 0; + int i; + + for (i = 0; i < list->count; i++) { + result = acpi_power_on(list->handles[i]); + if (result) { + __acpi_power_off_list(list, i); + break; + } + } + + return result; +} + /** * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in * ACPI 3.0) _PSW (Power State Wake) @@ -458,10 +487,7 @@ int acpi_power_get_inferred_state(struct acpi_device *device, int *state) int acpi_power_transition(struct acpi_device *device, int state) { - int result = 0; - struct acpi_handle_list *cl = NULL; /* Current Resources */ - struct acpi_handle_list *tl = NULL; /* Target Resources */ - int i = 0; + int result; if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3)) return -EINVAL; @@ -473,37 +499,20 @@ int acpi_power_transition(struct acpi_device *device, int state) || (device->power.state > ACPI_STATE_D3)) return -ENODEV; - cl = &device->power.states[device->power.state].resources; - tl = &device->power.states[state].resources; - /* TBD: Resources must be ordered. */ /* * First we reference all power resources required in the target list - * (e.g. so the device doesn't lose power while transitioning). + * (e.g. so the device doesn't lose power while transitioning). Then, + * we dereference all power resources used in the current list. */ - for (i = 0; i < tl->count; i++) { - result = acpi_power_on(tl->handles[i]); - if (result) - goto end; - } + result = acpi_power_on_list(&device->power.states[state].resources); + if (!result) + acpi_power_off_list( + &device->power.states[device->power.state].resources); - /* - * Then we dereference all power resources used in the current list. - */ - for (i = 0; i < cl->count; i++) { - result = acpi_power_off_device(cl->handles[i]); - if (result) - goto end; - } - - end: - if (result) - device->power.state = ACPI_STATE_UNKNOWN; - else { - /* We shouldn't change the state till all above operations succeed */ - device->power.state = state; - } + /* We shouldn't change the state unless the above operations succeed. */ + device->power.state = result ? ACPI_STATE_UNKNOWN : state; return result; }