From 26ff2762108010976e2785c605cdc7ac6882da11 Mon Sep 17 00:00:00 2001 From: Ander Conselvan de Oliveira Date: Tue, 28 Oct 2014 15:10:12 +0200 Subject: [PATCH] drm/i915: Add kerneldoc for intel_pipe_update_{start, end} Note that a later patch will use these functions in some other file and drop the static. Hence the kerneldoc looks appropriate. Signed-off-by: Ander Conselvan de Oliveira Reviewed-by: Paulo Zanoni [danvet: Add comment that the functions will become non-static shortly.] Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_sprite.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_sprite.c b/drivers/gpu/drm/i915/intel_sprite.c index 8c70c54e048d..c692adea4332 100644 --- a/drivers/gpu/drm/i915/intel_sprite.c +++ b/drivers/gpu/drm/i915/intel_sprite.c @@ -60,6 +60,22 @@ static int usecs_to_scanlines(const struct drm_display_mode *mode, int usecs) return DIV_ROUND_UP(usecs * mode->crtc_clock, 1000 * mode->crtc_htotal); } +/** + * intel_pipe_update_start() - start update of a set of display registers + * @crtc: the crtc of which the registers are going to be updated + * @start_vbl_count: vblank counter return pointer used for error checking + * + * Mark the start of an update to pipe registers that should be updated + * atomically regarding vblank. If the next vblank will happens within + * the next 100 us, this function waits until the vblank passes. + * + * After a successful call to this function, interrupts will be disabled + * until a subsequent call to intel_pipe_update_end(). That is done to + * avoid random delays. The value written to @start_vbl_count should be + * supplied to intel_pipe_update_end() for error checking. + * + * Return: true if the call was successful + */ static bool intel_pipe_update_start(struct intel_crtc *crtc, uint32_t *start_vbl_count) { struct drm_device *dev = crtc->base.dev; @@ -126,6 +142,15 @@ static bool intel_pipe_update_start(struct intel_crtc *crtc, uint32_t *start_vbl return true; } +/** + * intel_pipe_update_end() - end update of a set of display registers + * @crtc: the crtc of which the registers were updated + * @start_vbl_count: start vblank counter (used for error checking) + * + * Mark the end of an update started with intel_pipe_update_start(). This + * re-enables interrupts and verifies the update was actually completed + * before a vblank using the value of @start_vbl_count. + */ static void intel_pipe_update_end(struct intel_crtc *crtc, u32 start_vbl_count) { struct drm_device *dev = crtc->base.dev;