Re: [PATCH 5/9] drm/doc: Polish docs for drm_mode_object

Archit Taneja
2016-08-25T12:25:52Z

On 08/18/2016 02:26 AM, Daniel Vetter wrote:
> I figured an overview section here is overkill, and better
> to just document the 2 structures themselves well enough.
>
> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> ---
> drivers/gpu/drm/drm_mode_object.c | 9 +++++++
> include/drm/drm_mode_object.h | 50 ++++++++++++++++++++++++++++++++++++---
> 2 files changed, 56 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_mode_object.c b/drivers/gpu/drm/drm_mode_object.c
> index a92aeed51156..a4dd3fa258b4 100644
> --- a/drivers/gpu/drm/drm_mode_object.c
> +++ b/drivers/gpu/drm/drm_mode_object.c
> @@ -222,6 +222,12 @@ EXPORT_SYMBOL(drm_object_attach_property);
> * changes the software state of the property, it does not call into the
> * driver's ->set_property callback.
> *
> + * Note that atomic drivers should not have any need to call this, the core will
> + * ensure consistency of values reported back to userspace through the
> + * appropriate ->atomic_get_property callback. Only legacy drivers should call
> + * this function to update the tracked value (after clamping and other
> + * restrictions have been applied).
> + *
> * Returns:
> * Zero on success, error code on failure.
> */
> @@ -252,6 +258,9 @@ EXPORT_SYMBOL(drm_object_property_set_value);
> * value this might be out of sync with the hardware, depending upon the driver
> * and property.
> *
> + * Atomic drivers should never call this function directly, the core will read
> + * out property values through the various ->atomic_get_property callbacks.
> + *
> * Returns:
> * Zero on success, error code on failure.
> */
> diff --git a/include/drm/drm_mode_object.h b/include/drm/drm_mode_object.h
> index b8adb6425f2a..7967ffeda3c4 100644
> --- a/include/drm/drm_mode_object.h
> +++ b/include/drm/drm_mode_object.h
> @@ -27,6 +27,28 @@
> struct drm_object_properties;
> struct drm_property;
>
> +/**
> + * struct drm_mode_object - base structure for modeset objecst

s/objecst/object

> + * @id: userspace visible identifier
> + * @type: type of the object, one of DRM_MODE_OBJECT\_\*
> + * @properties: properties attached to this object, including values
> + * @refcount: reference count for objects which with dynamic lifetime
> + * @free_cb: free function callback, only set for objects with dynamic lifetime
> + *
> + * Base structure for modeset objects visible to userspace. Objects can be
> + * looked up using drm_mode_object_find(). Besides basic uapi interface
> + * properties like @id and @type it provides two servies:

s/servies/services

> + *
> + * - It tracks attached properties and their values. This is used by &drm_crtc,
> + * &drm_plane and &drm_connector. Properties are attached by calling
> + * drm_object_attach_property() before the object is visible to userspace.
> + *
> + * - For objects with dynamic lifetimes (as indicated by a non-NULL @free_cb) it
> + * provides reference counting through drm_mode_object_reference() and
> + * drm_mode_object_unreference(). This is used by &drm_framebuffer,
> + * &drm_connector and &drm_property_blob. These objects provide specialized
> + * reference counting wrappers.
> + */
> struct drm_mode_object {
> uint32_t id;
> uint32_t type;
> @@ -36,16 +58,38 @@ struct drm_mode_object {
> };
>
> #define DRM_OBJECT_MAX_PROPERTY 24
> +/**
> + * struct drm_object_properties - property tracking for &drm_mode_object
> + */
> struct drm_object_properties {
> + /**
> + * @count: number of valid properties, must be less than or equal to
> + * DRM_OBJECT_MAX_PROPERTY.
> + */
> +
> int count;
> - /* NOTE: if we ever start dynamically destroying properties (ie.
> + /**
> + * @properties: Array of pointers to &drm_property.
> + *
> + * NOTE: if we ever start dynamically destroying properties (ie.
> * not at drm_mode_config_cleanup() time), then we'd have to do
> * a better job of detaching property from mode objects to avoid
> * dangling property pointers:
> */
> struct drm_property *properties[DRM_OBJECT_MAX_PROPERTY];
> - /* do not read/write values directly, but use drm_object_property_get_value()
> - * and drm_object_property_set_value():
> +
> + /**
> + * @values: Array to store the property values, matching @properties. Do
> + * not read/write values directly, but use
> + * drm_object_property_get_value() and drm_object_property_set_value().
> + *
> + * Note that atomic drivers do not store mutable properties in this
> + * aray, but only the decoded values in the corresponding state

s/aray/array

Otherwise:

Reviewed-by: Archit Taneja <architt@codeaurora.org>

Archit

> + * structure. The decoding is done using the ->atomic_get_property and
> + * ->atomic_set_property hooks of the corresponding object. Hence atomic
> + * drivers should not use drm_object_property_set_value() and
> + * drm_object_property_get_value() on mutable objects, i.e. those
> + * without the DRM_MODE_PROP_IMMUTABLE flag set.
> */
> uint64_t values[DRM_OBJECT_MAX_PROPERTY];
> };
>

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