drm/mediatek: gamma: Use bitfield macros

Make the code more robust and improve readability by using bitfield
macros instead of open coding bit operations.

Reviewed-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20231012095736.100784-7-angelogioacchino.delregno@collabora.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
index 9a8f9306f0762cef23681523306c3faac9580970..b0180b746b5aa01e8c6de108ef0e478c8cd3777e 100644 (file)
--- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
@@ -3,6 +3,7 @@
  * Copyright (c) 2021 MediaTek Inc.
  */
 
+#include <linux/bitfield.h>
 #include <linux/clk.h>
 #include <linux/component.h>
 #include <linux/module.h>
@@ -21,8 +22,14 @@
 #define GAMMA_LUT_EN                                   BIT(1)
 #define GAMMA_DITHERING                                        BIT(2)
 #define DISP_GAMMA_SIZE                                0x0030
+#define DISP_GAMMA_SIZE_HSIZE                          GENMASK(28, 16)
+#define DISP_GAMMA_SIZE_VSIZE                          GENMASK(12, 0)
 #define DISP_GAMMA_LUT                         0x0700
 
+#define DISP_GAMMA_LUT_10BIT_R                 GENMASK(29, 20)
+#define DISP_GAMMA_LUT_10BIT_G                 GENMASK(19, 10)
+#define DISP_GAMMA_LUT_10BIT_B                 GENMASK(9, 0)
+
 struct mtk_disp_gamma_data {
        bool has_dither;
        bool lut_diff;
@@ -97,9 +104,9 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs, struct drm_crt
                hwlut.blue = drm_color_lut_extract(lut[i].blue, 10);
 
                if (!lut_diff || (i % 2 == 0)) {
-                       word = (hwlut.red << 20) +
-                              (hwlut.green << 10) +
-                              hwlut.red;
+                       word = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, hwlut.red);
+                       word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, hwlut.green);
+                       word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, hwlut.blue);
                } else {
                        diff.red = lut[i].red - lut[i - 1].red;
                        diff.red = drm_color_lut_extract(diff.red, 10);
@@ -110,9 +117,9 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs, struct drm_crt
                        diff.blue = lut[i].blue - lut[i - 1].blue;
                        diff.blue = drm_color_lut_extract(diff.blue, 10);
 
-                       word = (diff.blue << 20) +
-                              (diff.green << 10) +
-                              diff.red;
+                       word = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R, diff.red);
+                       word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G, diff.green);
+                       word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B, diff.blue);
                }
                writel(word, lut_base + i * 4);
        }
@@ -120,7 +127,7 @@ void mtk_gamma_set_common(struct device *dev, void __iomem *regs, struct drm_crt
        cfg_val = readl(regs + DISP_GAMMA_CFG);
 
        /* Enable the gamma table */
-       cfg_val |= GAMMA_LUT_EN;
+       cfg_val |= FIELD_PREP(GAMMA_LUT_EN, 1);
 
        writel(cfg_val, regs + DISP_GAMMA_CFG);
 }
@@ -137,9 +144,12 @@ void mtk_gamma_config(struct device *dev, unsigned int w,
                      unsigned int bpc, struct cmdq_pkt *cmdq_pkt)
 {
        struct mtk_disp_gamma *gamma = dev_get_drvdata(dev);
+       u32 sz;
+
+       sz = FIELD_PREP(DISP_GAMMA_SIZE_HSIZE, w);
+       sz |= FIELD_PREP(DISP_GAMMA_SIZE_VSIZE, h);
 
-       mtk_ddp_write(cmdq_pkt, h << 16 | w, &gamma->cmdq_reg, gamma->regs,
-                     DISP_GAMMA_SIZE);
+       mtk_ddp_write(cmdq_pkt, sz, &gamma->cmdq_reg, gamma->regs, DISP_GAMMA_SIZE);
        if (gamma->data && gamma->data->has_dither)
                mtk_dither_set_common(gamma->regs, &gamma->cmdq_reg, bpc,
                                      DISP_GAMMA_CFG, GAMMA_DITHERING, cmdq_pkt);