diff options
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/acpi/device_pm.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c index c4d0a1c912f0..3d96e4da2d98 100644 --- a/drivers/acpi/device_pm.c +++ b/drivers/acpi/device_pm.c @@ -543,6 +543,7 @@ static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev, unsigned long long ret; int d_min, d_max; bool wakeup = false; + bool has_sxd = false; acpi_status status; /* @@ -581,6 +582,10 @@ static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev, else return -ENODATA; } + + if (status == AE_OK) + has_sxd = true; + d_min = ret; wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid && adev->wakeup.sleep_state >= target_state; @@ -599,7 +604,11 @@ static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev, method[3] = 'W'; status = acpi_evaluate_integer(handle, method, NULL, &ret); if (status == AE_NOT_FOUND) { - if (target_state > ACPI_STATE_S0) + /* No _SxW. In this case, the ACPI spec says that we + * must not go into any power state deeper than the + * value returned from _SxD. + */ + if (has_sxd && target_state > ACPI_STATE_S0) d_max = d_min; } else if (ACPI_SUCCESS(status) && ret <= ACPI_STATE_D3_COLD) { /* Fall back to D3cold if ret is not a valid state. */ |