drm/udl: Add constants for display-mode registers

Add constants for the registers the contain various display-mode
parameters and update the mode-setting function. No functional
changes.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221006095355.23579-13-tzimmermann@suse.de

drivers/gpu/drm/udl/udl_modeset.c

@@ -126,78 +126,40 @@ static char *udl_set_register_lfsr16(char *wrptr, u8 reg, u16 value)
 }
 
 /*
- * This takes a standard fbdev screeninfo struct and all of its monitor mode
- * details and converts them into the DisplayLink equivalent register commands.
-  ERR(vreg(dev,               0x00, (color_depth == 16) ? 0 : 1));
-  ERR(vreg_lfsr16(dev,        0x01, xDisplayStart));
-  ERR(vreg_lfsr16(dev,        0x03, xDisplayEnd));
-  ERR(vreg_lfsr16(dev,        0x05, yDisplayStart));
-  ERR(vreg_lfsr16(dev,        0x07, yDisplayEnd));
-  ERR(vreg_lfsr16(dev,        0x09, xEndCount));
-  ERR(vreg_lfsr16(dev,        0x0B, hSyncStart));
-  ERR(vreg_lfsr16(dev,        0x0D, hSyncEnd));
-  ERR(vreg_big_endian(dev,    0x0F, hPixels));
-  ERR(vreg_lfsr16(dev,        0x11, yEndCount));
-  ERR(vreg_lfsr16(dev,        0x13, vSyncStart));
-  ERR(vreg_lfsr16(dev,        0x15, vSyncEnd));
-  ERR(vreg_big_endian(dev,    0x17, vPixels));
-  ERR(vreg_little_endian(dev, 0x1B, pixelClock5KHz));
-
-  ERR(vreg(dev,               0x1F, 0));
-
-  ERR(vbuf(dev, WRITE_VIDREG_UNLOCK, DSIZEOF(WRITE_VIDREG_UNLOCK)));
+ * Takes a DRM display mode and converts it into the DisplayLink
+ * equivalent register commands.
  */
-static char *udl_set_vid_cmds(char *wrptr, struct drm_display_mode *mode)
+static char *udl_set_display_mode(char *buf, struct drm_display_mode *mode)
 {
-	u16 xds, yds;
-	u16 xde, yde;
-	u16 yec;
+	u16 reg01 = mode->crtc_htotal - mode->crtc_hsync_start;
+	u16 reg03 = reg01 + mode->crtc_hdisplay;
+	u16 reg05 = mode->crtc_vtotal - mode->crtc_vsync_start;
+	u16 reg07 = reg05 + mode->crtc_vdisplay;
+	u16 reg09 = mode->crtc_htotal - 1;
+	u16 reg0b = 1; /* libdlo hardcodes hsync start to 1 */
+	u16 reg0d = mode->crtc_hsync_end - mode->crtc_hsync_start + 1;
+	u16 reg0f = mode->hdisplay;
+	u16 reg11 = mode->crtc_vtotal;
+	u16 reg13 = 0; /* libdlo hardcodes vsync start to 0 */
+	u16 reg15 = mode->crtc_vsync_end - mode->crtc_vsync_start;
+	u16 reg17 = mode->crtc_vdisplay;
+	u16 reg1b = mode->clock / 5;
+
+	buf = udl_set_register_lfsr16(buf, UDL_REG_XDISPLAYSTART, reg01);
+	buf = udl_set_register_lfsr16(buf, UDL_REG_XDISPLAYEND, reg03);
+	buf = udl_set_register_lfsr16(buf, UDL_REG_YDISPLAYSTART, reg05);
+	buf = udl_set_register_lfsr16(buf, UDL_REG_YDISPLAYEND, reg07);
+	buf = udl_set_register_lfsr16(buf, UDL_REG_XENDCOUNT, reg09);
+	buf = udl_set_register_lfsr16(buf, UDL_REG_HSYNCSTART, reg0b);
+	buf = udl_set_register_lfsr16(buf, UDL_REG_HSYNCEND, reg0d);
+	buf = udl_set_register_16(buf, UDL_REG_HPIXELS, reg0f);
+	buf = udl_set_register_lfsr16(buf, UDL_REG_YENDCOUNT, reg11);
+	buf = udl_set_register_lfsr16(buf, UDL_REG_VSYNCSTART, reg13);
+	buf = udl_set_register_lfsr16(buf, UDL_REG_VSYNCEND, reg15);
+	buf = udl_set_register_16(buf, UDL_REG_VPIXELS, reg17);
+	buf = udl_set_register_16be(buf, UDL_REG_PIXELCLOCK5KHZ, reg1b);
 
-	/* x display start */
-	xds = mode->crtc_htotal - mode->crtc_hsync_start;
-	wrptr = udl_set_register_lfsr16(wrptr, 0x01, xds);
-	/* x display end */
-	xde = xds + mode->crtc_hdisplay;
-	wrptr = udl_set_register_lfsr16(wrptr, 0x03, xde);
-
-	/* y display start */
-	yds = mode->crtc_vtotal - mode->crtc_vsync_start;
-	wrptr = udl_set_register_lfsr16(wrptr, 0x05, yds);
-	/* y display end */
-	yde = yds + mode->crtc_vdisplay;
-	wrptr = udl_set_register_lfsr16(wrptr, 0x07, yde);
-
-	/* x end count is active + blanking - 1 */
-	wrptr = udl_set_register_lfsr16(wrptr, 0x09,
-					mode->crtc_htotal - 1);
-
-	/* libdlo hardcodes hsync start to 1 */
-	wrptr = udl_set_register_lfsr16(wrptr, 0x0B, 1);
-
-	/* hsync end is width of sync pulse + 1 */
-	wrptr = udl_set_register_lfsr16(wrptr, 0x0D,
-					mode->crtc_hsync_end - mode->crtc_hsync_start + 1);
-
-	/* hpixels is active pixels */
-	wrptr = udl_set_register_16(wrptr, 0x0F, mode->hdisplay);
-
-	/* yendcount is vertical active + vertical blanking */
-	yec = mode->crtc_vtotal;
-	wrptr = udl_set_register_lfsr16(wrptr, 0x11, yec);
-
-	/* libdlo hardcodes vsync start to 0 */
-	wrptr = udl_set_register_lfsr16(wrptr, 0x13, 0);
-
-	/* vsync end is width of vsync pulse */
-	wrptr = udl_set_register_lfsr16(wrptr, 0x15, mode->crtc_vsync_end - mode->crtc_vsync_start);
-
-	/* vpixels is active pixels */
-	wrptr = udl_set_register_16(wrptr, 0x17, mode->crtc_vdisplay);
-
-	wrptr = udl_set_register_16be(wrptr, 0x1B,
-				      mode->clock / 5);
-
-	return wrptr;
+	return buf;
 }
 
 static char *udl_dummy_render(char *wrptr)
@@ -362,7 +324,7 @@ static void udl_crtc_helper_atomic_enable(struct drm_crtc *crtc, struct drm_atom
 	buf = udl_set_base16bpp(buf, 0);
 	/* set base for 8bpp segment to end of fb */
 	buf = udl_set_base8bpp(buf, 2 * mode->vdisplay * mode->hdisplay);
-	buf = udl_set_vid_cmds(buf, mode);
+	buf = udl_set_display_mode(buf, mode);
 	buf = udl_set_blank_mode(buf, UDL_BLANKMODE_ON);
 	buf = udl_vidreg_unlock(buf);
 	buf = udl_dummy_render(buf);

drivers/gpu/drm/udl/udl_proto.h

@@ -5,6 +5,21 @@
 
 #define UDL_COLORDEPTH_16BPP		0
 
+/* Display-mode settings */
+#define UDL_REG_XDISPLAYSTART		0x01
+#define UDL_REG_XDISPLAYEND		0x03
+#define UDL_REG_YDISPLAYSTART		0x05
+#define UDL_REG_YDISPLAYEND		0x07
+#define UDL_REG_XENDCOUNT		0x09
+#define UDL_REG_HSYNCSTART		0x0b
+#define UDL_REG_HSYNCEND		0x0d
+#define UDL_REG_HPIXELS			0x0f
+#define UDL_REG_YENDCOUNT		0x11
+#define UDL_REG_VSYNCSTART		0x13
+#define UDL_REG_VSYNCEND		0x15
+#define UDL_REG_VPIXELS			0x17
+#define UDL_REG_PIXELCLOCK5KHZ		0x1b
+
 /* On/Off for driving the DisplayLink framebuffer to the display */
 #define UDL_REG_BLANKMODE		0x1f
 #define UDL_BLANKMODE_ON		0x00 /* hsync and vsync on, visible */