linux-kernel - [PATCH] drm/kms/atomic: Used existing func for checking fb geometry

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Message-Id: <20180727083812epcas5p39f97180e85def2b4b4c1b68af2e83b41~FLPg9mkWQ2043620436epcas5p3U@epcas5p3.samsung.com>
Date:   Fri, 27 Jul 2018 14:08:02 +0530
From:   Satendra Singh Thakur <satendra.t@...sung.com>
To:     Gustavo Padovan <gustavo@...ovan.org>,
        Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
        Sean Paul <seanpaul@...omium.org>,
        David Airlie <airlied@...ux.ie>,
        dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org
Cc:     vineet.j@...sung.com, hemanshu.s@...sung.com, sst2005@...il.com,
        Satendra Singh Thakur <satendra.t@...sung.com>
Subject: [PATCH] drm/kms/atomic: Used existing func for checking fb geometry

1.In the func drm_atomic_plane_check, the fb geometry checking code
can be replaced by func drm_framebuffer_check_src_coords, this will
remove several redundant lines of code.
2. Currently, in the func drm_atomic_plane_check;
there are 3 if statements in the beginning with total 5 conditions.
these conditions are
crtc is NULL but fb is non-NULL
if (state->crtc && !state->fb)
crtc is non-NULL but fb is NULL
if (state->fb && !state->crtc)
crtc is NULL (and fb is also NULL)
if (!state->crtc)

The same code can be re-written using 2 if statements and 4 conditions.
first we check whether crtc and fb both are NULL
if (!state->crtc && !state->fb)
then we check either crtc or fb is NULL
if (!state->crtc || !state->fb)

Signed-off-by: Satendra Singh Thakur <satendra.t@...sung.com>
---
 drivers/gpu/drm/drm_atomic.c | 37 +++++++++----------------------------
 1 file changed, 9 insertions(+), 28 deletions(-)

diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 895741e..1cddab8 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -909,22 +909,16 @@ plane_switching_crtc(struct drm_atomic_state *state,
 static int drm_atomic_plane_check(struct drm_plane *plane,
 		struct drm_plane_state *state)
 {
-	unsigned int fb_width, fb_height;
 	int ret;
 
-	/* either *both* CRTC and FB must be set, or neither */
-	if (state->crtc && !state->fb) {
-		DRM_DEBUG_ATOMIC("CRTC set but no FB\n");
-		return -EINVAL;
-	} else if (state->fb && !state->crtc) {
-		DRM_DEBUG_ATOMIC("FB set but no CRTC\n");
-		return -EINVAL;
-	}
-
 	/* if disabled, we don't care about the rest of the state: */
-	if (!state->crtc)
+	if (!state->crtc && !state->fb)
 		return 0;
-
+	/* both CRTC and FB must be set*/
+	if (!state->crtc || !state->fb) {
+		DRM_DEBUG_ATOMIC("Either no CRTC or no FB\n");
+		return -EINVAL;
+	}
 	/* Check whether this plane is usable on this CRTC */
 	if (!(plane->possible_crtcs & drm_crtc_mask(state->crtc))) {
 		DRM_DEBUG_ATOMIC("Invalid crtc for plane\n");
@@ -954,24 +948,11 @@ static int drm_atomic_plane_check(struct drm_plane *plane,
 		return -ERANGE;
 	}
 
-	fb_width = state->fb->width << 16;
-	fb_height = state->fb->height << 16;
-
 	/* Make sure source coordinates are inside the fb. */
-	if (state->src_w > fb_width ||
-	    state->src_x > fb_width - state->src_w ||
-	    state->src_h > fb_height ||
-	    state->src_y > fb_height - state->src_h) {
-		DRM_DEBUG_ATOMIC("Invalid source coordinates "
-				 "%u.%06ux%u.%06u+%u.%06u+%u.%06u (fb %ux%u)\n",
-				 state->src_w >> 16, ((state->src_w & 0xffff) * 15625) >> 10,
-				 state->src_h >> 16, ((state->src_h & 0xffff) * 15625) >> 10,
-				 state->src_x >> 16, ((state->src_x & 0xffff) * 15625) >> 10,
-				 state->src_y >> 16, ((state->src_y & 0xffff) * 15625) >> 10,
-				 state->fb->width, state->fb->height);
+	ret = drm_framebuffer_check_src_coords(state->src_x, state->src_y,
+		state->src_w, state->src_h, state->fb);
+	if (ret)
 		return -ENOSPC;
-	}
-
 	if (plane_switching_crtc(state->state, plane, state)) {
 		DRM_DEBUG_ATOMIC("[PLANE:%d:%s] switching CRTC directly\n",
 				 plane->base.id, plane->name);
-- 
2.7.4