Commit ff6c6bc5 authored by Francois Dugast's avatar Francois Dugast Committed by Rodrigo Vivi
Browse files

drm/xe/uapi: Document use of size in drm_xe_device_query 



Document the behavior of the driver for IOCTL DRM_IOCTL_XE_DEVICE_QUERY
depending on the size value provided in struct drm_xe_device_query.

Reviewed-by: default avatarRodrigo Vivi <rodrigo.vivi@intel.com>
Acked-by: default avatarJosé Roberto de Souza <jose.souza@intel.com>
Acked-by: default avatarMateusz Naklicki <mateusz.naklicki@intel.com>
Signed-off-by: default avatarFrancois Dugast <francois.dugast@intel.com>
Signed-off-by: default avatarRodrigo Vivi <rodrigo.vivi@intel.com>
parent 4efaadd3

include/uapi/drm/xe_drm.h

+9 −3
Original line number Diff line number Diff line
@@ -467,9 +467,15 @@ struct drm_xe_query_topology_mask { 
 * struct drm_xe_device_query - Input of &DRM_IOCTL_XE_DEVICE_QUERY - main

 * structure to query device information

 *

 * If size is set to 0, the driver fills it with the required size for the

 * requested type of data to query. If size is equal to the required size,

 * the queried information is copied into data.

 * The user selects the type of data to query among DRM_XE_DEVICE_QUERY_*

 * and sets the value in the query member. This determines the type of

 * the structure provided by the driver in data, among struct drm_xe_query_*.

 *

 * If size is set to 0, the driver fills it with the required size for

 * the requested type of data to query. If size is equal to the required

 * size, the queried information is copied into data. If size is set to

 * a value different from 0 and different from the required size, the

 * IOCTL call returns -EINVAL.

 *

 * For example the following code snippet allows retrieving and printing

 * information about the device engines with DRM_XE_DEVICE_QUERY_ENGINES: