video: zynqmp: Prevent use of uninitialised variables

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@linaro.org>
Link: https://lore.kernel.org/r/20251001-video_zynqmp-v1-1-34f1e59b9c34@linaro.org
Signed-off-by: Michal Simek <michal.simek@amd.com>

diff --git a/drivers/video/zynqmp/zynqmp_dpsub.c b/drivers/video/zynqmp/zynqmp_dpsub.c
index 52af23c..a0efd33 100644 (file)
--- 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));
        }
 }