drm/edid: Remove arbitrary EDID extension limit

Signed-off-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

5 files changed, 15 insertions, 24 deletions

diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index d91fb8c0b7b..aa24f2f9dc0 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -33,6 +33,7 @@
 #include "drm.h"
 #include "drmP.h"
 #include "drm_crtc.h"
+#include "drm_edid.h"
 
 struct drm_prop_enum_list {
         int type;
@@ -2349,7 +2350,7 @@ int drm_mode_connector_update_edid_property(struct drm_connector *connector,
                                             struct edid *edid)
 {
         struct drm_device *dev = connector->dev;
-        int ret = 0;
+        int ret = 0, size;
 
         if (connector->edid_blob_ptr)
                 drm_property_destroy_blob(dev, connector->edid_blob_ptr);
@@ -2361,7 +2362,9 @@ int drm_mode_connector_update_edid_property(struct drm_connector *connector,
                 return ret;
         }
 
-        connector->edid_blob_ptr = drm_property_create_blob(connector->dev, 128, edid);
+        size = EDID_LENGTH * (1 + edid->extensions);
+        connector->edid_blob_ptr = drm_property_create_blob(connector->dev,
+                                                            size, edid);
 
         ret = drm_connector_property_set_value(connector,
                                                dev->mode_config.edid_property,
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 58b67932f04..cf24ecab6a4 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -1325,7 +1325,6 @@ static int add_detailed_info_eedid(struct drm_connector *connector,
         int i, modes = 0;
         char *edid_ext = NULL;
         struct detailed_timing *timing;
-        int edid_ext_num;
         int start_offset, end_offset;
         int timing_level;
 
@@ -1342,19 +1341,15 @@ static int add_detailed_info_eedid(struct drm_connector *connector,
                 return 0;
         }
 
-        /* Chose real EDID extension number */
-        edid_ext_num = edid->extensions > DRM_MAX_EDID_EXT_NUM ?
-                DRM_MAX_EDID_EXT_NUM : edid->extensions;
-
         /* Find CEA extension */
-        for (i = 0; i < edid_ext_num; i++) {
+        for (i = 0; i < edid->extensions; i++) {
                 edid_ext = (char *)edid + EDID_LENGTH * (i + 1);
                 /* This block is CEA extension */
                 if (edid_ext[0] == 0x02)
                         break;
         }
 
-        if (i == edid_ext_num) {
+        if (i == edid->extensions) {
                 /* if there is no additional timing EDID block, return */
                 return 0;
         }
@@ -1393,7 +1388,7 @@ static int add_detailed_info_eedid(struct drm_connector *connector,
 bool drm_detect_hdmi_monitor(struct edid *edid)
 {
         char *edid_ext = NULL;
-        int i, hdmi_id, edid_ext_num;
+        int i, hdmi_id;
         int start_offset, end_offset;
         bool is_hdmi = false;
 
@@ -1401,19 +1396,15 @@ bool drm_detect_hdmi_monitor(struct edid *edid)
         if (edid == NULL || edid->extensions == 0)
                 goto end;
 
-        /* Chose real EDID extension number */
-        edid_ext_num = edid->extensions > DRM_MAX_EDID_EXT_NUM ?
-                       DRM_MAX_EDID_EXT_NUM : edid->extensions;
-
         /* Find CEA extension */
-        for (i = 0; i < edid_ext_num; i++) {
+        for (i = 0; i < edid->extensions; i++) {
                 edid_ext = (char *)edid + EDID_LENGTH * (i + 1);
                 /* This block is CEA extension */
                 if (edid_ext[0] == 0x02)
                         break;
         }
 
-        if (i == edid_ext_num)
+        if (i == edid->extensions)
                 goto end;
 
         /* Data block offset in CEA extension block */
diff --git a/drivers/gpu/drm/drm_sysfs.c b/drivers/gpu/drm/drm_sysfs.c
index 014ce24761b..7b7c83f6041 100644
--- a/drivers/gpu/drm/drm_sysfs.c
+++ b/drivers/gpu/drm/drm_sysfs.c
@@ -332,7 +332,7 @@ static struct device_attribute connector_attrs_opt1[] = {
 static struct bin_attribute edid_attr = {
         .attr.name = "edid",
         .attr.mode = 0444,
-        .size = 128,
+        .size = 0,
         .read = edid_show,
 };
 
diff --git a/drivers/gpu/drm/radeon/radeon_combios.c b/drivers/gpu/drm/radeon/radeon_combios.c
index 2becdeda68a..20f38b85c70 100644
--- a/drivers/gpu/drm/radeon/radeon_combios.c
+++ b/drivers/gpu/drm/radeon/radeon_combios.c
@@ -450,17 +450,17 @@ bool radeon_combios_check_hardcoded_edid(struct radeon_device *rdev)
 {
         int edid_info;
         struct edid *edid;
+        unsigned char *raw;
         edid_info = combios_get_table_offset(rdev->ddev, COMBIOS_HARDCODED_EDID_TABLE);
         if (!edid_info)
                 return false;
 
-        edid = kmalloc(EDID_LENGTH * (DRM_MAX_EDID_EXT_NUM + 1),
-                       GFP_KERNEL);
+        raw = rdev->bios + edid_info;
+        edid = kmalloc(EDID_LENGTH * (raw[0x7e] + 1), GFP_KERNEL);
         if (edid == NULL)
                 return false;
 
-        memcpy((unsigned char *)edid,
-               (unsigned char *)(rdev->bios + edid_info), EDID_LENGTH);
+        memcpy((unsigned char *)edid, raw, EDID_LENGTH * (raw[0x7e] + 1));
 
         if (!drm_edid_is_valid(edid)) {
                 kfree(edid);
diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h
index b4209898f11..d33c3e03860 100644
--- a/include/drm/drm_edid.h
+++ b/include/drm/drm_edid.h
@@ -201,7 +201,4 @@ struct edid {
 
 #define EDID_PRODUCT_ID(e) ((e)->prod_code[0] | ((e)->prod_code[1] << 8))
 
-/* define the number of Extension EDID block */
-#define DRM_MAX_EDID_EXT_NUM 4
-
 #endif /* __DRM_EDID_H__ */