[PATCH] drm/udl: port over blanking code from udlfb.

[Dave Airlie]

From: Dave Airlie <airl...@redhat.com>

This ports over the dpms code from udlfb, and should mean
a better chance of turning on some udl devices.

Signed-off-by: Dave Airlie <airlied at redhat.com>
---
 drivers/gpu/drm/udl/udl_modeset.c |   44 +++++++++++++++++++++++++++++++------
 1 file changed, 37 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/udl/udl_modeset.c 
b/drivers/gpu/drm/udl/udl_modeset.c
index 0d78167..fb2df7f 100644
--- a/drivers/gpu/drm/udl/udl_modeset.c
+++ b/drivers/gpu/drm/udl/udl_modeset.c
@@ -45,12 +45,25 @@ static char *udl_vidreg_unlock(char *buf)
  *  0x01 H and V sync off (screen blank but powered)
  *  0x07 DPMS powerdown (requires modeset to come back)
  */
-static char *udl_enable_hvsync(char *buf, bool enable)
+static char *udl_set_blank(char *buf, int dpms_mode)
 {
-       if (enable)
-               return udl_set_register(buf, 0x1F, 0x00);
-       else
-               return udl_set_register(buf, 0x1F, 0x07);
+       u8 reg;
+       switch (dpms_mode) {
+       case DRM_MODE_DPMS_OFF:
+               reg = 0x07;
+               break;
+       case DRM_MODE_DPMS_STANDBY:
+               reg = 0x05;
+               break;
+       case DRM_MODE_DPMS_SUSPEND:
+               reg = 0x01;
+               break;
+       case DRM_MODE_DPMS_ON:
+               reg = 0x00;
+               break;
+       }
+
+       return udl_set_register(buf, 0x1f, reg);
 }

 static char *udl_set_color_depth(char *buf, u8 selection)
@@ -199,6 +212,20 @@ static char *udl_set_vid_cmds(char *wrptr, struct 
drm_display_mode *mode)
        return wrptr;
 }

+static char *udl_dummy_render(char *wrptr)
+{
+       *wrptr++ = 0xAF;
+       *wrptr++ = 0x6A; /* copy */
+       *wrptr++ = 0x00; /* from addr */
+       *wrptr++ = 0x00;
+       *wrptr++ = 0x00;
+       *wrptr++ = 0x01; /* one pixel */
+       *wrptr++ = 0x00; /* to address */
+       *wrptr++ = 0x00;
+       *wrptr++ = 0x00;
+       return wrptr;
+}
+
 static int udl_crtc_write_mode_to_hw(struct drm_crtc *crtc)
 {
        struct drm_device *dev = crtc->dev;
@@ -235,9 +262,10 @@ static void udl_crtc_dpms(struct drm_crtc *crtc, int mode)

                buf = (char *)urb->transfer_buffer;
                buf = udl_vidreg_lock(buf);
-               buf = udl_enable_hvsync(buf, false);
+               buf = udl_set_blank(buf, mode);
                buf = udl_vidreg_unlock(buf);

+               buf = udl_dummy_render(buf);
                retval = udl_submit_urb(dev, urb, buf - (char *)
                                        urb->transfer_buffer);
        } else {
@@ -306,9 +334,11 @@ static int udl_crtc_mode_set(struct drm_crtc *crtc,
        wrptr = udl_set_base8bpp(wrptr, 2 * mode->vdisplay * mode->hdisplay);

        wrptr = udl_set_vid_cmds(wrptr, adjusted_mode);
-       wrptr = udl_enable_hvsync(wrptr, true);
+       wrptr = udl_set_blank(wrptr, DRM_MODE_DPMS_ON);
        wrptr = udl_vidreg_unlock(wrptr);

+       wrptr = udl_dummy_render(wrptr);
+
        ufb->active_16 = true;
        if (old_fb) {
                struct udl_framebuffer *uold_fb = to_udl_fb(old_fb);
-- 
1.7.10.2