[PATCH 15/16] drm/udl: Add register constants for framebuffer scanout addresses

[Thomas Zimmermann]

Add register constants for the framebuffer scanout addresses and
update the related helper functions. No functional changes.

Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
---
 drivers/gpu/drm/udl/udl_modeset.c | 28 ++++++++++++++++++++--------
 drivers/gpu/drm/udl/udl_proto.h   |  8 ++++++++
 2 files changed, 28 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/udl/udl_modeset.c b/drivers/gpu/drm/udl/udl_modeset.c
index b6aebfaae03d..df0b70f3ddf1 100644
--- a/drivers/gpu/drm/udl/udl_modeset.c
+++ b/drivers/gpu/drm/udl/udl_modeset.c
@@ -59,23 +59,35 @@ static char *udl_set_color_depth(char *buf, u8 selection)
 	return udl_set_register(buf, UDL_REG_COLORDEPTH, selection);
 }
 
-static char *udl_set_base16bpp(char *wrptr, u32 base)
+static char *udl_set_base16bpp(char *buf, u32 base)
 {
 	/* the base pointer is 16 bits wide, 0x20 is hi byte. */
-	wrptr = udl_set_register(wrptr, 0x20, base >> 16);
-	wrptr = udl_set_register(wrptr, 0x21, base >> 8);
-	return udl_set_register(wrptr, 0x22, base);
+	u8 reg20 = (base & 0xff0000) >> 16;
+	u8 reg21 = (base & 0x00ff00) >> 8;
+	u8 reg22 = (base & 0x0000ff);
+
+	buf = udl_set_register(buf, UDL_REG_BASE16BPP_ADDR2, reg20);
+	buf = udl_set_register(buf, UDL_REG_BASE16BPP_ADDR1, reg21);
+	buf = udl_set_register(buf, UDL_REG_BASE16BPP_ADDR0, reg22);
+
+	return buf;
 }
 
 /*
  * DisplayLink HW has separate 16bpp and 8bpp framebuffers.
  * In 24bpp modes, the low 323 RGB bits go in the 8bpp framebuffer
  */
-static char *udl_set_base8bpp(char *wrptr, u32 base)
+static char *udl_set_base8bpp(char *buf, u32 base)
 {
-	wrptr = udl_set_register(wrptr, 0x26, base >> 16);
-	wrptr = udl_set_register(wrptr, 0x27, base >> 8);
-	return udl_set_register(wrptr, 0x28, base);
+	u8 reg26 = (base & 0xff0000) >> 16;
+	u8 reg27 = (base & 0x00ff00) >> 8;
+	u8 reg28 = (base & 0x0000ff);
+
+	buf = udl_set_register(buf, UDL_REG_BASE8BPP_ADDR2, reg26);
+	buf = udl_set_register(buf, UDL_REG_BASE8BPP_ADDR1, reg27);
+	buf = udl_set_register(buf, UDL_REG_BASE8BPP_ADDR0, reg28);
+
+	return buf;
 }
 
 static char *udl_set_register_16(char *wrptr, u8 reg, u16 value)
diff --git a/drivers/gpu/drm/udl/udl_proto.h b/drivers/gpu/drm/udl/udl_proto.h
index 8e7d1a090644..3e7fcb43cb04 100644
--- a/drivers/gpu/drm/udl/udl_proto.h
+++ b/drivers/gpu/drm/udl/udl_proto.h
@@ -31,6 +31,14 @@
 #define UDL_BLANKMODE_HSYNC_OFF		0x05 /* hsync off, blanked */
 #define UDL_BLANKMODE_POWERDOWN		0x07 /* powered off; requires modeset */
 
+/* Framebuffer address */
+#define UDL_REG_BASE16BPP_ADDR2		0x20
+#define UDL_REG_BASE16BPP_ADDR1		0x21
+#define UDL_REG_BASE16BPP_ADDR0		0x22
+#define UDL_REG_BASE8BPP_ADDR2		0x26
+#define UDL_REG_BASE8BPP_ADDR1		0x27
+#define UDL_REG_BASE8BPP_ADDR0		0x28
+
 /* Lock/unlock video registers */
 #define UDL_REG_VIDREG			0xff
 #define UDL_VIDREG_LOCK			0x00
-- 
2.37.3