drm/modes: Parse overscan properties

Properly configuring the overscan properties might be needed for the
initial setup of the framebuffer for display that still have overscan.
Let's allow for more properties on the kernel command line to setup each
margin.

Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/e481f1628e3768ca49226ec2115cfa4dfcbd5e4c.1560783090.git-series.maxime.ripard@bootlin.com

diff --git a/Documentation/fb/modedb.txt b/Documentation/fb/modedb.txt
index 52418c6..1dd5a52 100644 (file)
--- a/Documentation/fb/modedb.txt
+++ b/Documentation/fb/modedb.txt
@@ -57,6 +57,8 @@ Options can also be passed after the mode, using commas as separator.
 
 Valid options are:
 
+  - margin_top, margin_bottom, margin_left, margin_right (integer):
+    Number of pixels in the margins, typically to deal with overscan on TVs
   - reflect_x (boolean): Perform an axial symmetry on the X axis
   - reflect_y (boolean): Perform an axial symmetry on the Y axis
   - rotate (integer): Rotate the initial framebuffer by x

diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c
index dc6d112..57e6408 100644 (file)
--- a/drivers/gpu/drm/drm_modes.c
+++ b/drivers/gpu/drm/drm_modes.c
@@ -1609,6 +1609,50 @@ static int drm_mode_parse_cmdline_options(char *str, size_t len,
                } else if (!strncmp(option, "reflect_y", delim - option)) {
                        rotation |= DRM_MODE_REFLECT_Y;
                        sep = delim;
+               } else if (!strncmp(option, "margin_right", delim - option)) {
+                       const char *value = delim + 1;
+                       unsigned int margin;
+
+                       margin = simple_strtol(value, &sep, 10);
+
+                       /* Make sure we have parsed something */
+                       if (sep == value)
+                               return -EINVAL;
+
+                       mode->tv_margins.right = margin;
+               } else if (!strncmp(option, "margin_left", delim - option)) {
+                       const char *value = delim + 1;
+                       unsigned int margin;
+
+                       margin = simple_strtol(value, &sep, 10);
+
+                       /* Make sure we have parsed something */
+                       if (sep == value)
+                               return -EINVAL;
+
+                       mode->tv_margins.left = margin;
+               } else if (!strncmp(option, "margin_top", delim - option)) {
+                       const char *value = delim + 1;
+                       unsigned int margin;
+
+                       margin = simple_strtol(value, &sep, 10);
+
+                       /* Make sure we have parsed something */
+                       if (sep == value)
+                               return -EINVAL;
+
+                       mode->tv_margins.top = margin;
+               } else if (!strncmp(option, "margin_bottom", delim - option)) {
+                       const char *value = delim + 1;
+                       unsigned int margin;
+
+                       margin = simple_strtol(value, &sep, 10);
+
+                       /* Make sure we have parsed something */
+                       if (sep == value)
+                               return -EINVAL;
+
+                       mode->tv_margins.bottom = margin;
                } else {
                        return -EINVAL;
                }

diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index b22e315..ca745d9 100644 (file)
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -1054,6 +1054,11 @@ struct drm_cmdline_mode {
         * DRM_MODE_ROTATE_0 and DRM_MODE_ROTATE_180.
         */
        unsigned int rotation_reflection;
+
+       /**
+        * @tv_margins: TV margins to apply to the mode.
+        */
+       struct drm_connector_tv_margins tv_margins;
 };
 
 /**