[PATCH 05/10] drm/doc: Polish for drm_plane.[hc]

[Archit Taneja]

On 09/19/2016 06:43 PM, Daniel Vetter wrote:
> On Fri, Sep 02, 2016 at 03:00:38PM +0530, Archit Taneja wrote:
>>
>>
>> On 8/31/2016 9:39 PM, Daniel Vetter wrote:
>>> Big thing is untangling and carefully documenting the different uapi
>>> types of planes. I also sprinkled a few more cross references around
>>> to make this easier to discover.
>>>
>>> As usual, remove the kerneldoc for internal functions which are not
>>> exported. Aside: We should probably go OCD on all the ioctl handlers
>>> and consistenly give them an _ioctl postfix.
>>>
>>> Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
>>> ---
>>>   Documentation/gpu/drm-kms.rst |  47 +--------------
>>>   drivers/gpu/drm/drm_crtc.c    |   6 +-
>>>   drivers/gpu/drm/drm_plane.c   | 132 ++++++++----------------------------------
>>>   include/drm/drm_plane.h       |  57 +++++++++++++++++-
>>>   4 files changed, 86 insertions(+), 156 deletions(-)
>>>
>> <snip>
>>
>>> +/**
>>> + * enum drm_plane_type - uapi plane type enumeration
>>> + *
>>> + * For historical reasons not all planes are made the same. This enumeration is
>>> + * used to tell the different types of planes apart to implement the different
>>> + * uapi semantics for them. For userspace which is universal plane aware and
>>> + * which is using that atomic IOCTL there's no difference between these planes
>>> + * (beyong what the driver and hardware can support of course).
>>> + *
>>> + * For compatibility with legacy userspace, only overlay planes are made
>>> + * available to userspace by default. Userspace clients may set the
>>> + * DRM_CLIENT_CAP_UNIVERSAL_PLANES client capability bit to indicate that they
>>> + * wish to receive a universal plane list containing all plane types. See also
>>> + * drm_for_each_legacy_plane().
>>> + */
>>>   enum drm_plane_type {
>>> -	DRM_PLANE_TYPE_OVERLAY,
>>
>> Any reason why you moved this down? I guess there is no harm, but people
>> might be printing plane type while debugging, and they'd assume
>> DRM_PLANE_TYPE_OVERLAY=0
>
> I think starting out with 0 for the primary plane makes a lot more sense,
> and since it's an internal thing we can change it however we want. I also
> think from a documentation pov it reads better if the 2 special planes
> (primary and cursor) are first.
>
> But I'm happy to shuffle it back if you feel strongly the other way round.

No, it's fine. The series looks good too.

Thanks,
Archit

> -Daniel
>
>>
>> Thanks,
>> Archit
>>
>>> +	/**
>>> +	 * @DRM_PLANE_TYPE_PRIMARY:
>>> +	 *
>>> +	 * Primary planes represent a "main" plane for a CRTC.  Primary planes
>>> +	 * are the planes operated upon by CRTC modesetting and flipping
>>> +	 * operations described in the page_flip and set_config hooks in struct
>>> +	 * &drm_crtc_funcs.
>>> +	 */
>>>   	DRM_PLANE_TYPE_PRIMARY,
>>> +
>>> +	/**
>>> +	 * @DRM_PLANE_TYPE_CURSOR:
>>> +	 *
>>> +	 * Cursor planes represent a "cursor" plane for a CRTC.  Cursor planes
>>> +	 * are the planes operated upon by the DRM_IOCTL_MODE_CURSOR and
>>> +	 * DRM_IOCTL_MODE_CURSOR2 IOCTLs.
>>> +	 */
>>>   	DRM_PLANE_TYPE_CURSOR,
>>> +
>>> +	/**
>>> +	 * @DRM_PLANE_TYPE_OVERLAY:
>>> +	 *
>>> +	 * Overlay planes represent all non-primary, non-cursor planes. Some
>>> +	 * drivers refer to these types of planes as "sprites" internally.
>>> +	 */
>>> +	DRM_PLANE_TYPE_OVERLAY,
>>>   };
>>>
>>>
>>> @@ -458,11 +496,26 @@ static inline struct drm_plane *drm_plane_find(struct drm_device *dev,
>>>   	list_for_each_entry((plane), &(dev)->mode_config.plane_list, head) \
>>>   		for_each_if ((plane_mask) & (1 << drm_plane_index(plane)))
>>>
>>> -/* Plane list iterator for legacy (overlay only) planes. */
>>> +/**
>>> + * drm_for_each_legacy_plane - iterate over all planes for legacy userspace
>>> + * @plane: the loop cursor
>>> + * @dev: the DRM device
>>> + *
>>> + * Iterate over all legacy planes of @dev, excluding primary and cursor planes.
>>> + * This is useful for implementing userspace apis when userspace is not
>>> + * universal plane aware. See also enum &drm_plane_type.
>>> + */
>>>   #define drm_for_each_legacy_plane(plane, dev) \
>>>   	list_for_each_entry(plane, &(dev)->mode_config.plane_list, head) \
>>>   		for_each_if (plane->type == DRM_PLANE_TYPE_OVERLAY)
>>>
>>> +/**
>>> + * drm_for_each_plane - iterate over all planes
>>> + * @plane: the loop cursor
>>> + * @dev: the DRM device
>>> + *
>>> + * Iterate over all planes of @dev, include primary and cursor planes.
>>> + */
>>>   #define drm_for_each_plane(plane, dev) \
>>>   	list_for_each_entry(plane, &(dev)->mode_config.plane_list, head)
>>>
>>>
>>
>> --
>> Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
>> a Linux Foundation Collaborative Project
>

-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project