linux-kernel - [PATCH v4 09/12] [media] vivid: Local optimization

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Date:	Mon, 18 Jul 2016 14:42:13 +0200
From:	Ricardo Ribalda Delgado <ricardo.ribalda@...il.com>
To:	Jonathan Corbet <corbet@....net>,
	Mauro Carvalho Chehab <mchehab@...nel.org>,
	Hans Verkuil <hverkuil@...all.nl>,
	Markus Heiser <markus.heiser@...marIT.de>,
	Laurent Pinchart <laurent.pinchart@...asonboard.com>,
	Helen Mae Koike Fornazier <helen.koike@...labora.co.uk>,
	Antti Palosaari <crope@....fi>,
	Philipp Zabel <p.zabel@...gutronix.de>,
	Shuah Khan <shuahkh@....samsung.com>,
	linux-doc@...r.kernel.org, linux-kernel@...r.kernel.org,
	linux-media@...r.kernel.org
Cc:	Ricardo Ribalda Delgado <ricardo.ribalda@...il.com>
Subject: [PATCH v4 09/12] [media] vivid: Local optimization

Avoid duplicated data shifts when possible.

Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@...il.com>
---
 drivers/media/common/v4l2-tpg/v4l2-tpg-core.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c b/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c
index a26172575e56..7f284c591f25 100644
--- a/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c
+++ b/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c
@@ -919,13 +919,14 @@ static void precalculate_color(struct tpg_data *tpg, int k)
 			color_to_ycbcr(tpg, r, g, b, &y, &cb, &cr);
 
 		if (tpg->real_quantization == V4L2_QUANTIZATION_LIM_RANGE) {
-			y = clamp(y, 16 << 4, 235 << 4);
-			cb = clamp(cb, 16 << 4, 240 << 4);
-			cr = clamp(cr, 16 << 4, 240 << 4);
+			y = clamp(y >> 4, 16, 235);
+			cb = clamp(cb >> 4, 16, 240);
+			cr = clamp(cr >> 4, 16, 240);
+		} else {
+			y = clamp(y >> 4, 1, 254);
+			cb = clamp(cb >> 4, 1, 254);
+			cr = clamp(cr >> 4, 1, 254);
 		}
-		y = clamp(y >> 4, 1, 254);
-		cb = clamp(cb >> 4, 1, 254);
-		cr = clamp(cr >> 4, 1, 254);
 		switch (tpg->fourcc) {
 		case V4L2_PIX_FMT_YUV444:
 			y >>= 4;
-- 
2.8.1