This parameter allows the set of EDID quirks to be changed at
runtime. The syntax is

        vendor/product/quirks,vendor/product/quirks,...

where vendor is the three-letter EDID vendor value, product is the
EDID product id which may be prefixed with 0x to for hex instead of
decimal values and quirks is the replacement quirks value from the
list in drm_edid.c.

Signed-off-by: Keith Packard <kei...@keithp.com>
---
 drivers/gpu/drm/drm_edid.c | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 5dc742b27ca0..63b4587faddd 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -98,6 +98,12 @@ struct detailed_mode_closure {
 #define LEVEL_GTF2     2
 #define LEVEL_CVT      3
 
+#define EDID_QUIRK_PARAM_LEN   256
+static char edid_quirk_param[EDID_QUIRK_PARAM_LEN];
+module_param_string(edid_quirk_param, edid_quirk_param, 
sizeof(edid_quirk_param), 0644);
+MODULE_PARM_DESC(edid_quirk_param, "Extra EDID quirks, "
+                "format is 'vendor/product/quirks;...' ");
+
 static const struct edid_quirk {
        char vendor[4];
        int product_id;
@@ -1774,8 +1780,24 @@ static bool edid_vendor(const struct edid *edid, const 
char *vendor)
 static u32 edid_get_quirks(const struct edid *edid)
 {
        const struct edid_quirk *quirk;
+       const char *q;
        int i;
 
+       for (q = edid_quirk_param; q && *q; q = strchr(q, ',')) {
+               char    vendor[4];
+               int     product_id;
+               int     quirks;
+
+               while (*q == ',')
+                       q++;
+
+               if (sscanf(q, "%3s/%i/%i", vendor, &product_id, &quirks) == 3) {
+                       if (edid_vendor(edid, vendor) &&
+                           (EDID_PRODUCT_ID(edid) == product_id))
+                               return quirks;
+               }
+       }
+
        for (i = 0; i < ARRAY_SIZE(edid_quirk_list); i++) {
                quirk = &edid_quirk_list[i];
 
-- 
2.18.0

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Reply via email to