From ca8d40ca194dfb573e59a5e42b88da83e63a6630 Mon Sep 17 00:00:00 2001 From: Alex Deucher Date: Thu, 19 Apr 2018 13:56:41 -0500 Subject: [PATCH] drm/amdgpu/pm: document power_dpm_state This is a legacy file and is only provided for backwards compatibility. Acked-by: Felix Kuehling Reviewed-by: Huang Rui Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c | 31 ++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c index ee11e92cc4d2..e33e0f4c4a28 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c @@ -77,6 +77,37 @@ void amdgpu_pm_acpi_event_handler(struct amdgpu_device *adev) } } +/** + * DOC: power_dpm_state + * + * This is a legacy interface and is only provided for backwards compatibility. + * The amdgpu driver provides a sysfs API for adjusting certain power + * related parameters. The file power_dpm_state is used for this. + * It accepts the following arguments: + * - battery + * - balanced + * - performance + * + * battery + * + * On older GPUs, the vbios provided a special power state for battery + * operation. Selecting battery switched to this state. This is no + * longer provided on newer GPUs so the option does nothing in that case. + * + * balanced + * + * On older GPUs, the vbios provided a special power state for balanced + * operation. Selecting balanced switched to this state. This is no + * longer provided on newer GPUs so the option does nothing in that case. + * + * performance + * + * On older GPUs, the vbios provided a special power state for performance + * operation. Selecting performance switched to this state. This is no + * longer provided on newer GPUs so the option does nothing in that case. + * + */ + static ssize_t amdgpu_get_dpm_state(struct device *dev, struct device_attribute *attr, char *buf)