drm: Export the command-line mode parser

In the absence of configuration data for providing the fixed mode for
a panel, I would like to be able to pass such modes along a separate
module paramenter. To do so, I then need to parse a modeline from a
string, which drm is already capable of. Export that capability to the
drivers.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 154 insertions, 0 deletions

diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c
index 25bf87390f53..207b7ebf8150 100644
--- a/drivers/gpu/drm/drm_modes.c
+++ b/drivers/gpu/drm/drm_modes.c
@@ -974,3 +974,157 @@ void drm_mode_connector_list_update(struct drm_connector *connector)
         }
 }
 EXPORT_SYMBOL(drm_mode_connector_list_update);
+
+/**
+ * drm_mode_parse_command_line_for_connector - parse command line for connector
+ * @mode_option - per connector mode option
+ * @connector - connector to parse line for
+ *
+ * This parses the connector specific then generic command lines for
+ * modes and options to configure the connector.
+ *
+ * This uses the same parameters as the fb modedb.c, except for extra
+ *      <xres>x<yres>[M][R][-<bpp>][@<refresh>][i][m][eDd]
+ *
+ * enable/enable Digital/disable bit at the end
+ */
+bool drm_mode_parse_command_line_for_connector(const char *mode_option,
+                                               struct drm_connector *connector,
+                                               struct drm_cmdline_mode *mode)
+{
+        const char *name;
+        unsigned int namelen;
+        int res_specified = 0, bpp_specified = 0, refresh_specified = 0;
+        unsigned int xres = 0, yres = 0, bpp = 32, refresh = 0;
+        int yres_specified = 0, cvt = 0, rb = 0, interlace = 0, margins = 0;
+        int i;
+        enum drm_connector_force force = DRM_FORCE_UNSPECIFIED;
+
+        if (!mode_option)
+                mode_option = fb_mode_option;
+
+        if (!mode_option) {
+                mode->specified = false;
+                return false;
+        }
+
+        name = mode_option;
+        namelen = strlen(name);
+        for (i = namelen-1; i >= 0; i--) {
+                switch (name[i]) {
+                case '@':
+                        namelen = i;
+                        if (!refresh_specified && !bpp_specified &&
+                            !yres_specified) {
+                                refresh = simple_strtol(&name[i+1], NULL, 10);
+                                refresh_specified = 1;
+                                if (cvt || rb)
+                                        cvt = 0;
+                        } else
+                                goto done;
+                        break;
+                case '-':
+                        namelen = i;
+                        if (!bpp_specified && !yres_specified) {
+                                bpp = simple_strtol(&name[i+1], NULL, 10);
+                                bpp_specified = 1;
+                                if (cvt || rb)
+                                        cvt = 0;
+                        } else
+                                goto done;
+                        break;
+                case 'x':
+                        if (!yres_specified) {
+                                yres = simple_strtol(&name[i+1], NULL, 10);
+                                yres_specified = 1;
+                        } else
+                                goto done;
+                case '0' ... '9':
+                        break;
+                case 'M':
+                        if (!yres_specified)
+                                cvt = 1;
+                        break;
+                case 'R':
+                        if (cvt)
+                                rb = 1;
+                        break;
+                case 'm':
+                        if (!cvt)
+                                margins = 1;
+                        break;
+                case 'i':
+                        if (!cvt)
+                                interlace = 1;
+                        break;
+                case 'e':
+                        force = DRM_FORCE_ON;
+                        break;
+                case 'D':
+                        if ((connector->connector_type != DRM_MODE_CONNECTOR_DVII) &&
+                            (connector->connector_type != DRM_MODE_CONNECTOR_HDMIB))
+                                force = DRM_FORCE_ON;
+                        else
+                                force = DRM_FORCE_ON_DIGITAL;
+                        break;
+                case 'd':
+                        force = DRM_FORCE_OFF;
+                        break;
+                default:
+                        goto done;
+                }
+        }
+        if (i < 0 && yres_specified) {
+                xres = simple_strtol(name, NULL, 10);
+                res_specified = 1;
+        }
+done:
+        if (res_specified) {
+                mode->specified = true;
+                mode->xres = xres;
+                mode->yres = yres;
+        }
+
+        if (refresh_specified) {
+                mode->refresh_specified = true;
+                mode->refresh = refresh;
+        }
+
+        if (bpp_specified) {
+                mode->bpp_specified = true;
+                mode->bpp = bpp;
+        }
+        mode->rb = rb ? true : false;
+        mode->cvt = cvt  ? true : false;
+        mode->interlace = interlace ? true : false;
+        mode->force = force;
+
+        return true;
+}
+EXPORT_SYMBOL(drm_mode_parse_command_line_for_connector);
+
+struct drm_display_mode *
+drm_mode_create_from_cmdline_mode(struct drm_device *dev,
+                                  struct drm_cmdline_mode *cmd)
+{
+        struct drm_display_mode *mode;
+
+        if (cmd->cvt)
+                mode = drm_cvt_mode(dev,
+                                    cmd->xres, cmd->yres,
+                                    cmd->refresh_specified ? cmd->refresh : 60,
+                                    cmd->rb, cmd->interlace,
+                                    cmd->margins);
+        else
+                mode = drm_gtf_mode(dev,
+                                    cmd->xres, cmd->yres,
+                                    cmd->refresh_specified ? cmd->refresh : 60,
+                                    cmd->interlace,
+                                    cmd->margins);
+        if (!mode)
+                return NULL;
+
+        drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);
+        return mode;
+}
+EXPORT_SYMBOL(drm_mode_create_from_cmdline_mode);