[PATCH v2 16/25] drm/mediatek: add ddp write register common api

[<yongqiang.niu@mediatek.com>]

From: Yongqiang Niu <yongqiang.niu@mediatek.com>

This patch add ddp write register common api
this is preparation patch for ovl/ovl_2l direct link
usecase.
in that case, we need this funtion to set one bit of ovl_2l
register

Signed-off-by: Yongqiang Niu <yongqiang.niu@mediatek.com>
---
 drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c | 11 +++++++++++
 drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h |  4 ++++
 2 files changed, 15 insertions(+)

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
index afd6ca2..72288b4 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
@@ -84,6 +84,17 @@
 #define DITHER_ADD_LSHIFT_G(x)			(((x) & 0x7) << 4)
 #define DITHER_ADD_RSHIFT_G(x)			(((x) & 0x7) << 0)
 
+void mtk_ddp_write_mask(unsigned int value,
+			struct mtk_ddp_comp *comp,
+			unsigned int offset,
+			unsigned int mask)
+{
+	unsigned int tmp = readl(comp->regs + offset);
+
+	tmp = (tmp & ~mask) | (value & mask);
+	writel(tmp, comp->regs + offset);
+}
+
 void mtk_dither_set(struct mtk_ddp_comp *comp, unsigned int bpc,
 		    unsigned int CFG)
 {
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h
index 20e8061..ed715ff 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h
+++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h
@@ -198,5 +198,9 @@ int mtk_ddp_comp_init(struct device *dev, struct device_node *comp_node,
 void mtk_ddp_comp_unregister(struct drm_device *drm, struct mtk_ddp_comp *comp);
 void mtk_dither_set(struct mtk_ddp_comp *comp, unsigned int bpc,
 		    unsigned int CFG);
+void mtk_ddp_write_mask(unsigned int value,
+			struct mtk_ddp_comp *comp,
+			unsigned int offset,
+			unsigned int mask);
 
 #endif /* MTK_DRM_DDP_COMP_H */
-- 
1.8.1.1.dirty