[PATCH v3 1/3] drm/edid: Add drm_edid_get_monitor_name()

Jim Bride
2016-04-11T16:14:20Z

In order to include monitor name information in debugfs
output we needed to add a function that would extract the
monitor name from the EDID, and that function needed to
reside in the file where the rest of the EDID helper
functions are implemented.

v2: Refactor to have drm_edid_get_monitor_name() and drm_edid_to_eld()
use a common helper function to extract the monitor name from the
edid. [Jani] + rebase.

v3: Minor changes suggested by Jani + rebase.

cc: dri-devel@lists.freedesktop.org
cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Jim Bride <jim.bride@linux.intel.com>
---
drivers/gpu/drm/drm_edid.c | 51 ++++++++++++++++++++++++++++++++++++++--------
include/drm/drm_crtc.h | 2 ++
2 files changed, 44 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 558ef9f..da30ce3 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -3293,6 +3293,46 @@ monitor_name(struct detailed_timing *t, void *data)
*(u8 **)data = t->data.other_data.data.str.str;
}

+static int get_monitor_name(struct edid *edid, char name[13])
+{
+ char *edid_name = NULL;
+ int mnl;
+
+ if (!edid || !name)
+ return 0;
+
+ drm_for_each_detailed_block((u8 *)edid, monitor_name, &edid_name);
+ for (mnl = 0; edid_name && mnl < 13; mnl++) {
+ if (edid_name[mnl] == 0x0a)
+ break;
+
+ name[mnl] = edid_name[mnl];
+ }
+
+ return mnl;
+}
+
+/**
+ * drm_edid_get_monitor_name - fetch the monitor name from the edid
+ * @edid: monitor EDID information
+ * @name: pointer to a character array to hold the name of the monitor
+ * @bufsize: The size of the name buffer (should be at least 13 chars.)
+ *
+ */
+void drm_edid_get_monitor_name(struct edid *edid, char *name, int bufsize)
+{
+ int name_length = -1;
+ char buf[13];
+
+ if (bufsize <= 0)
+ return;
+
+ name_length = min(get_monitor_name(edid, buf), bufsize - 1);
+ memcpy(name, buf, name_length);
+ name[name_length] = '\0';
+}
+EXPORT_SYMBOL(drm_edid_get_monitor_name);
+
/**
* drm_edid_to_eld - build ELD from EDID
* @connector: connector corresponding to the HDMI/DP sink
@@ -3306,7 +3346,6 @@ void drm_edid_to_eld(struct drm_connector *connector, struct edid *edid)
{
uint8_t *eld = connector->eld;
u8 *cea;
- u8 *name;
u8 *db;
int total_sad_count = 0;
int mnl;
@@ -3320,14 +3359,8 @@ void drm_edid_to_eld(struct drm_connector *connector, struct edid *edid)
return;
}

- name = NULL;
- drm_for_each_detailed_block((u8 *)edid, monitor_name, &name);
- /* max: 13 bytes EDID, 16 bytes ELD */
- for (mnl = 0; name && mnl < 13; mnl++) {
- if (name[mnl] == 0x0a)
- break;
- eld[20 + mnl] = name[mnl];
- }
+ mnl = get_monitor_name(edid, eld + 20);
+
eld[4] = (cea[1] << 5) | mnl;
DRM_DEBUG_KMS("ELD monitor %s\n", eld + 20);

diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 8cb377c..6d46842 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -2500,6 +2500,8 @@ extern int drm_edid_header_is_valid(const u8 *raw_edid);
extern bool drm_edid_block_valid(u8 *raw_edid, int block, bool print_bad_edid,
bool *edid_corrupt);
extern bool drm_edid_is_valid(struct edid *edid);
+extern void drm_edid_get_monitor_name(struct edid *edid, char *name,
+ int buflen);

extern struct drm_tile_group *drm_mode_create_tile_group(struct drm_device *dev,
char topology[8]);
--
2.5.0