fbdev: when parsing E-EDID blocks, also use SVD entries

Add parsing of E-EDID SVD entries. In this first version only a few
CEA/EIA-861E modes are implemented, more can be added as needed.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 33 insertions, 4 deletions

diff --git a/drivers/video/fbmon.c b/drivers/video/fbmon.c
index b25399abcf49..4f57485f8c54 100644
--- a/drivers/video/fbmon.c
+++ b/drivers/video/fbmon.c
@@ -983,7 +983,8 @@ void fb_edid_add_monspecs(unsigned char *edid, struct fb_monspecs *specs)
         unsigned char *block;
         struct fb_videomode *m;
         int num = 0, i;
-        u8 edt[(128 - 4) / DETAILED_TIMING_DESCRIPTION_SIZE];
+        u8 svd[64], edt[(128 - 4) / DETAILED_TIMING_DESCRIPTION_SIZE];
+        u8 pos = 4, svd_n = 0;
 
         if (!edid)
                 return;
@@ -995,6 +996,21 @@ void fb_edid_add_monspecs(unsigned char *edid, struct fb_monspecs *specs)
             edid[2] < 4 || edid[2] > 128 - DETAILED_TIMING_DESCRIPTION_SIZE)
                 return;
 
+        DPRINTK("  Short Video Descriptors\n");
+
+        while (pos < edid[2]) {
+                u8 len = edid[pos] & 0x1f, type = (edid[pos] >> 5) & 7;
+                pr_debug("Data block %u of %u bytes\n", type, len);
+                if (type == 2)
+                        for (i = pos; i < pos + len; i++) {
+                                u8 idx = edid[pos + i] & 0x7f;
+                                svd[svd_n++] = idx;
+                                pr_debug("N%sative mode #%d\n",
+                                         edid[pos + i] & 0x80 ? "" : "on-n", idx);
+                        }
+                pos += len + 1;
+        }
+
         block = edid + edid[2];
 
         DPRINTK("  Extended Detailed Timings\n");
@@ -1005,10 +1021,10 @@ void fb_edid_add_monspecs(unsigned char *edid, struct fb_monspecs *specs)
                         edt[num++] = block - edid;
 
         /* Yikes, EDID data is totally useless */
-        if (!num)
+        if (!(num + svd_n))
                 return;
 
-        m = kzalloc((specs->modedb_len + num) *
+        m = kzalloc((specs->modedb_len + num + svd_n) *
                        sizeof(struct fb_videomode), GFP_KERNEL);
 
         if (!m)
@@ -1023,9 +1039,22 @@ void fb_edid_add_monspecs(unsigned char *edid, struct fb_monspecs *specs)
                 pr_debug("Adding %ux%u@%u\n", m[i].xres, m[i].yres, m[i].refresh);
         }
 
+        for (i = specs->modedb_len + num; i < specs->modedb_len + num + svd_n; i++) {
+                int idx = svd[i - specs->modedb_len - num];
+                if (!idx || idx > 63) {
+                        pr_warning("Reserved SVD code %d\n", idx);
+                } else if (idx > ARRAY_SIZE(cea_modes) || !cea_modes[idx].xres) {
+                        pr_warning("Unimplemented SVD code %d\n", idx);
+                } else {
+                        memcpy(&m[i], cea_modes + idx, sizeof(m[i]));
+                        pr_debug("Adding SVD #%d: %ux%u@%u\n", idx,
+                                 m[i].xres, m[i].yres, m[i].refresh);
+                }
+        }
+
         kfree(specs->modedb);
         specs->modedb = m;
-        specs->modedb_len = specs->modedb_len + num;
+        specs->modedb_len = specs->modedb_len + num + svd_n;
 }
 
 /*