drm/doc: Polish kerneldoc for encoders
- Move missing bits into struct drm_encoder docs.
- Explain that encoders are 95% internal and only 5% uapi, and that in
general the uapi part is broken.
- Remove verbose comments for functions not exposed to drivers.
v2: Review from Archit:
- Appease checkpatch in the moved code.
- Make it clearer that bridges are not exposed to userspace.
Reviewed-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20160829082757.17913-2-daniel.vetter@ffwll.ch
diff --git a/include/drm/drm_encoder.h b/include/drm/drm_encoder.h
index 2712fd1..3d7350f 100644
--- a/include/drm/drm_encoder.h
+++ b/include/drm/drm_encoder.h
@@ -84,9 +84,6 @@
* @head: list management
* @base: base KMS object
* @name: human readable name, can be overwritten by the driver
- * @encoder_type: one of the DRM_MODE_ENCODER_<foo> types in drm_mode.h
- * @possible_crtcs: bitmask of potential CRTC bindings
- * @possible_clones: bitmask of potential sibling encoders for cloning
* @crtc: currently bound CRTC
* @bridge: bridge associated to the encoder
* @funcs: control functions
@@ -101,6 +98,32 @@
struct drm_mode_object base;
char *name;
+ /**
+ * @encoder_type:
+ *
+ * One of the DRM_MODE_ENCODER_<foo> types in drm_mode.h. The following
+ * encoder types are defined thus far:
+ *
+ * - DRM_MODE_ENCODER_DAC for VGA and analog on DVI-I/DVI-A.
+ *
+ * - DRM_MODE_ENCODER_TMDS for DVI, HDMI and (embedded) DisplayPort.
+ *
+ * - DRM_MODE_ENCODER_LVDS for display panels, or in general any panel
+ * with a proprietary parallel connector.
+ *
+ * - DRM_MODE_ENCODER_TVDAC for TV output (Composite, S-Video,
+ * Component, SCART).
+ *
+ * - DRM_MODE_ENCODER_VIRTUAL for virtual machine displays
+ *
+ * - DRM_MODE_ENCODER_DSI for panels connected using the DSI serial bus.
+ *
+ * - DRM_MODE_ENCODER_DPI for panels connected using the DPI parallel
+ * bus.
+ *
+ * - DRM_MODE_ENCODER_DPMST for special fake encoders used to allow
+ * mutliple DP MST streams to share one physical encoder.
+ */
int encoder_type;
/**
@@ -109,7 +132,34 @@
*/
unsigned index;
+ /**
+ * @possible_crtcs: Bitmask of potential CRTC bindings, using
+ * drm_crtc_index() as the index into the bitfield. The driver must set
+ * the bits for all &drm_crtc objects this encoder can be connected to
+ * before calling drm_encoder_init().
+ *
+ * In reality almost every driver gets this wrong.
+ *
+ * Note that since CRTC objects can't be hotplugged the assigned indices
+ * are stable and hence known before registering all objects.
+ */
uint32_t possible_crtcs;
+
+ /**
+ * @possible_clones: Bitmask of potential sibling encoders for cloning,
+ * using drm_encoder_index() as the index into the bitfield. The driver
+ * must set the bits for all &drm_encoder objects which can clone a
+ * &drm_crtc together with this encoder before calling
+ * drm_encoder_init(). Drivers should set the bit representing the
+ * encoder itself, too. Cloning bits should be set such that when two
+ * encoders can be used in a cloned configuration, they both should have
+ * each another bits set.
+ *
+ * In reality almost every driver gets this wrong.
+ *
+ * Note that since encoder objects can't be hotplugged the assigned indices
+ * are stable and hence known before registering all objects.
+ */
uint32_t possible_clones;
struct drm_crtc *crtc;
@@ -146,7 +196,7 @@
* @encoder: encoder to test
* @crtc: crtc to test
*
- * Return false if @encoder can't be driven by @crtc, true otherwise.
+ * Returns false if @encoder can't be driven by @crtc, true otherwise.
*/
static inline bool drm_encoder_crtc_ok(struct drm_encoder *encoder,
struct drm_crtc *crtc)
@@ -154,11 +204,21 @@
return !!(encoder->possible_crtcs & drm_crtc_mask(crtc));
}
+/**
+ * drm_encoder_find - find a &drm_encoder
+ * @dev: DRM device
+ * @id: encoder id
+ *
+ * Returns the encoder with @id, NULL if it doesn't exist. Simple wrapper around
+ * drm_mode_object_find().
+ */
static inline struct drm_encoder *drm_encoder_find(struct drm_device *dev,
- uint32_t id)
+ uint32_t id)
{
struct drm_mode_object *mo;
+
mo = drm_mode_object_find(dev, id, DRM_MODE_OBJECT_ENCODER);
+
return mo ? obj_to_encoder(mo) : NULL;
}