[2/3] drm/amdgpu: fall back to INPUT power for AVG power via INFO IOCTL

[Mario Limonciello]

On 10/2/2023 13:49, Alex Deucher wrote:
> For backwards compatibility with userspace.
> 
> Fixes: 47f1724db4fe ("drm/amd: Introduce `AMDGPU_PP_SENSOR_GPU_INPUT_POWER`")
> Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2897
> Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 7 ++++++-
>   1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> index 081bd28e2443..ce71f853931a 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> @@ -1077,7 +1077,12 @@ int amdgpu_info_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
>   			if (amdgpu_dpm_read_sensor(adev,
>   						   AMDGPU_PP_SENSOR_GPU_AVG_POWER,
>   						   (void *)&ui32, &ui32_size)) {
> -				return -EINVAL;

In order to encourage userspace software to move to the new dedicated 
IOCTL, what do you think about having a dev_warn_once() here?

> +				/* fall back to input power for backwards compat */
> +				if (amdgpu_dpm_read_sensor(adev,
> +							   AMDGPU_PP_SENSOR_GPU_INPUT_POWER,
> +							   (void *)&ui32, &ui32_size)) {
> +					return -EINVAL;
> +				}
>   			}
>   			ui32 >>= 8;
>   			break;