2 files changed, 78 insertions, 30 deletions

diff --git a/Documentation/fb/modedb.txt b/Documentation/fb/modedb.txt
index ec4dee75a354..16aa08453911 100644
--- a/Documentation/fb/modedb.txt
+++ b/Documentation/fb/modedb.txt
@@ -20,7 +20,7 @@ in a video= option, fbmem considers that to be a global video mode option.
 
 Valid mode specifiers (mode_option argument):
 
-    <xres>x<yres>[M][R][-<bpp>][@<refresh>][i][m]
+    <xres>x<yres>[M][R][-<bpp>][@<refresh>][i][m][eDd]
     <name>[-<bpp>][@<refresh>]
 
 with <xres>, <yres>, <bpp> and <refresh> decimal numbers and <name> a string.
@@ -36,6 +36,21 @@ pixels and 1.8% of yres).
 
        Sample usage: 1024x768M@60m - CVT timing with margins
 
+DRM drivers also add options to enable or disable outputs:
+
+'e' will force the display to be enabled, i.e. it will override the detection
+if a display is connected. 'D' will force the display to be enabled and use
+digital output. This is useful for outputs that have both analog and digital
+signals (e.g. HDMI and DVI-I). For other outputs it behaves like 'e'. If 'd'
+is specified the output is disabled.
+
+You can additionally specify which output the options matches to.
+To force the VGA output to be enabled and drive a specific mode say:
+    video=VGA-1:1280x1024@60me
+
+Specifying the option multiple times for different ports is possible, e.g.:
+    video=LVDS-1:d video=HDMI-1:D
+
 ***** oOo ***** oOo ***** oOo ***** oOo ***** oOo ***** oOo ***** oOo *****
 
 What is the VESA(TM) Coordinated Video Timings (CVT)?
@@ -132,5 +147,5 @@ There may be more modes.
     tridentfb   - Trident (Cyber)blade chipset frame buffer
     vt8623fb    - VIA 8623 frame buffer
 
-BTW, only a few drivers use this at the moment. Others are to follow
-(feel free to send patches).
+BTW, only a few fb drivers use this at the moment. Others are to follow
+(feel free to send patches). The DRM drivers also support this.
diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c
index c2d32f20e2fb..ad74fb4dc542 100644
--- a/drivers/gpu/drm/drm_modes.c
+++ b/drivers/gpu/drm/drm_modes.c
@@ -994,9 +994,10 @@ bool drm_mode_parse_command_line_for_connector(const char *mode_option,
 {
         const char *name;
         unsigned int namelen;
-        int res_specified = 0, bpp_specified = 0, refresh_specified = 0;
+        bool res_specified = false, bpp_specified = false, refresh_specified = false;
         unsigned int xres = 0, yres = 0, bpp = 32, refresh = 0;
-        int yres_specified = 0, cvt = 0, rb = 0, interlace = 0, margins = 0;
+        bool yres_specified = false, cvt = false, rb = false;
+        bool interlace = false, margins = false, was_digit = false;
         int i;
         enum drm_connector_force force = DRM_FORCE_UNSPECIFIED;
 
@@ -1015,54 +1016,65 @@ bool drm_mode_parse_command_line_for_connector(const char *mode_option,
         for (i = namelen-1; i >= 0; i--) {
                 switch (name[i]) {
                 case '@':
-                        namelen = i;
                         if (!refresh_specified && !bpp_specified &&
-                            !yres_specified) {
+                            !yres_specified && !cvt && !rb && was_digit) {
                                 refresh = simple_strtol(&name[i+1], NULL, 10);
-                                refresh_specified = 1;
-                                if (cvt || rb)
-                                        cvt = 0;
+                                refresh_specified = true;
+                                was_digit = false;
                         } else
                                 goto done;
                         break;
                 case '-':
-                        namelen = i;
-                        if (!bpp_specified && !yres_specified) {
+                        if (!bpp_specified && !yres_specified && !cvt &&
+                            !rb && was_digit) {
                                 bpp = simple_strtol(&name[i+1], NULL, 10);
-                                bpp_specified = 1;
-                                if (cvt || rb)
-                                        cvt = 0;
+                                bpp_specified = true;
+                                was_digit = false;
                         } else
                                 goto done;
                         break;
                 case 'x':
-                        if (!yres_specified) {
+                        if (!yres_specified && was_digit) {
                                 yres = simple_strtol(&name[i+1], NULL, 10);
-                                yres_specified = 1;
+                                yres_specified = true;
+                                was_digit = false;
                         } else
                                 goto done;
                 case '0' ... '9':
+                        was_digit = true;
                         break;
                 case 'M':
-                        if (!yres_specified)
-                                cvt = 1;
+                        if (yres_specified || cvt || was_digit)
+                                goto done;
+                        cvt = true;
                         break;
                 case 'R':
-                        if (cvt)
-                                rb = 1;
+                        if (yres_specified || cvt || rb || was_digit)
+                                goto done;
+                        rb = true;
                         break;
                 case 'm':
-                        if (!cvt)
-                                margins = 1;
+                        if (cvt || yres_specified || was_digit)
+                                goto done;
+                        margins = true;
                         break;
                 case 'i':
-                        if (!cvt)
-                                interlace = 1;
+                        if (cvt || yres_specified || was_digit)
+                                goto done;
+                        interlace = true;
                         break;
                 case 'e':
+                        if (yres_specified || bpp_specified || refresh_specified ||
+                            was_digit || (force != DRM_FORCE_UNSPECIFIED))
+                                goto done;
+
                         force = DRM_FORCE_ON;
                         break;
                 case 'D':
+                        if (yres_specified || bpp_specified || refresh_specified ||
+                            was_digit || (force != DRM_FORCE_UNSPECIFIED))
+                                goto done;
+
                         if ((connector->connector_type != DRM_MODE_CONNECTOR_DVII) &&
                             (connector->connector_type != DRM_MODE_CONNECTOR_HDMIB))
                                 force = DRM_FORCE_ON;
@@ -1070,17 +1082,37 @@ bool drm_mode_parse_command_line_for_connector(const char *mode_option,
                                 force = DRM_FORCE_ON_DIGITAL;
                         break;
                 case 'd':
+                        if (yres_specified || bpp_specified || refresh_specified ||
+                            was_digit || (force != DRM_FORCE_UNSPECIFIED))
+                                goto done;
+
                         force = DRM_FORCE_OFF;
                         break;
                 default:
                         goto done;
                 }
         }
+
         if (i < 0 && yres_specified) {
-                xres = simple_strtol(name, NULL, 10);
-                res_specified = 1;
+                char *ch;
+                xres = simple_strtol(name, &ch, 10);
+                if ((ch != NULL) && (*ch == 'x'))
+                        res_specified = true;
+                else
+                        i = ch - name;
+        } else if (!yres_specified && was_digit) {
+                /* catch mode that begins with digits but has no 'x' */
+                i = 0;
         }
 done:
+        if (i >= 0) {
+                printk(KERN_WARNING
+                        "parse error at position %i in video mode '%s'\n",
+                        i, name);
+                mode->specified = false;
+                return false;
+        }
+
         if (res_specified) {
                 mode->specified = true;
                 mode->xres = xres;
@@ -1096,9 +1128,10 @@ done:
                 mode->bpp_specified = true;
                 mode->bpp = bpp;
         }
-        mode->rb = rb ? true : false;
-        mode->cvt = cvt  ? true : false;
-        mode->interlace = interlace ? true : false;
+        mode->rb = rb;
+        mode->cvt = cvt;
+        mode->interlace = interlace;
+        mode->margins = margins;
         mode->force = force;
 
         return true;