[PATCH] video: zynqmp: Prevent use of uninitialised variables

[Andrew Goodbody]

The variables 'offset_matrix' and 'csc_matrix' will be used
uninitialised if video->is_rgb is false. Correct the logic so the
attempt to use uninitialised variables is not made. Also remove the use
of these variables as they seem to serve no useful purpose just being
aliases for arrays.

This issue was found by Smatch.

Signed-off-by: Andrew Goodbody <andrew.goodbody at linaro.org>
---
 drivers/video/zynqmp/zynqmp_dpsub.c | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/drivers/video/zynqmp/zynqmp_dpsub.c b/drivers/video/zynqmp/zynqmp_dpsub.c
index 52af23c3c83592af4442af4fa7e345b85dabd9d2..a0efd3393f5fe2c3a468caec4ad81deef18dbdbf 100644
--- a/drivers/video/zynqmp/zynqmp_dpsub.c
+++ b/drivers/video/zynqmp/zynqmp_dpsub.c
@@ -240,7 +240,6 @@ static void avbuf_video_select(struct udevice *dev, enum av_buf_video_stream vid
 static void config_gfx_pipeline(struct udevice *dev)
 {
 	struct zynqmp_dpsub_priv *dp_sub = dev_get_priv(dev);
-	u16 *csc_matrix, *offset_matrix;
 	u32 regval = 0, index = 0, *scaling_factors = NULL;
 	u16 rgb_coeffs[] = { 0x1000, 0x0000, 0x0000,
 			     0x0000, 0x1000, 0x0000,
@@ -262,19 +261,18 @@ static void config_gfx_pipeline(struct udevice *dev)
 								video->sampling_en;
 	writel(regval, dp_sub->base_addr + AVBUF_V_BLEND_LAYER1_CONTROL);
 
-	if (video->is_rgb) {
-		csc_matrix = rgb_coeffs;
-		offset_matrix = rgb_offset;
-	}
+	if (!video->is_rgb)
+		return;
+
 	/* Program Colorspace conversion coefficients */
 	for (index = 9; index < 12; index++) {
-		writel(offset_matrix[index - 9], dp_sub->base_addr +
+		writel(rgb_offset[index - 9], dp_sub->base_addr +
 		       AVBUF_V_BLEND_IN2CSC_COEFF0 + (index * 4));
 	}
 
 	/* Program Colorspace conversion matrix */
 	for (index = 0; index < 9; index++) {
-		writel(csc_matrix[index], dp_sub->base_addr +
+		writel(rgb_coeffs[index], dp_sub->base_addr +
 		       AVBUF_V_BLEND_IN2CSC_COEFF0 + (index * 4));
 	}
 }

---
base-commit: b2d5e46c67002e46ac339ef549ea18cf5adfcd87
change-id: 20251001-video_zynqmp-8822d6863aea

Best regards,
-- 
Andrew Goodbody <andrew.goodbody at linaro.org>