- monitor-get-edid:

  o minimal support for getting EDID from different DDC port
    (experimental, need testing before using it in monitor-edid)

this is inspired from SuSE's hwinfo. note:
- we may need to not redo vbe_check_vbe_info() for each vbe_get_edid_info() if
  we want to get many ports. It would need a little re-architecturing
  (since returning list in C is not great fun)
- hwinfo is probing ports 0,1 by default,
  (hwinfo says: some BIOSes crash when you try more)
  and 0,1,2 on Dell and nvidia-based laptops

4 files changed, 19 insertions, 14 deletions

diff --git a/NEWS b/NEWS
index d611931..73f6bf0 100644
--- a/NEWS
+++ b/NEWS
@@ -1,2 +1,4 @@
-- monitor-get-edid: skip /proc/acpi/video/**/EDID files which can't be valid
-  (#34417)
+- monitor-get-edid: 
+  o skip /proc/acpi/video/**/EDID files which can't be valid (#34417)
+  o minimal support for getting EDID from different DDC port
+    (experimental, need testing before using it in monitor-edid)
diff --git a/get-edid.h b/get-edid.h
index eb45d11..9de1cd9 100644
--- a/get-edid.h
+++ b/get-edid.h
@@ -1,4 +1,4 @@
 int verbose;
 
 struct hd_data_struct;
-int get_edid(struct hd_data_struct *hd_data, char *edid);
+int get_edid(struct hd_data_struct *hd_data, char *edid, int port);
diff --git a/monitor-get-edid-using-vbe.c b/monitor-get-edid-using-vbe.c
index 1b5a470..822820a 100644
--- a/monitor-get-edid-using-vbe.c
+++ b/monitor-get-edid-using-vbe.c
@@ -18,6 +18,7 @@ int main(int argc, char **argv)
 {
   char edid[256];
   int try_in_console = 0;
+  int port = 0;
   int i;
 
   /* Hardware Data defaults */
@@ -32,18 +33,19 @@ int main(int argc, char **argv)
   for (i = 1; i < argc; i++) {
 	const char *arg = argv[i];
     if (strcmp(arg, "-v") == 0) verbose = 1;
+    else if (strcmp(arg, "--port") == 0 && i+1 < argc) port = atoi(argv[++i]);
     else if (strcmp(arg, "--try-in-console") == 0) try_in_console = 1;
     else if (strcmp(arg, "--map-bios-vram") == 0) hd_data.flags.biosvram = 1;
 	else if (strcmp(arg, "--check-bios-crc") == 0) hd_data.flags.nobioscrc = 0;
 	else if (strcmp(arg, "--use-cpuemu") == 0) hd_data.flags.cpuemu = 1;
     else if (strcmp(arg, "-h") == 0 ||
 	     strcmp(arg, "--help") == 0) {
-      printf("usage: monitor-get-edid [-v]\n");
+      printf("usage: monitor-get-edid [-v] [--port <0-3>]\n");
       exit(1);
     }
   }
 
-  int size = get_edid(&hd_data, edid);
+  int size = get_edid(&hd_data, edid, port);
 
   if (!size && try_in_console) {
     int non_X_console = 1;
@@ -56,7 +58,7 @@ int main(int argc, char **argv)
 	ioctl(fd, VT_ACTIVATE, non_X_console) == 0 &&
 	ioctl(fd, VT_WAITACTIVE, non_X_console) == 0) {
       /* retrying */
-      size = get_edid(&hd_data, edid);
+      size = get_edid(&hd_data, edid, port);
 
       /* restore */
       ioctl(fd, VT_ACTIVATE, current.v_active) == 0 &&
diff --git a/vbe.c b/vbe.c
index 413ae2a..534dd0e 100644
--- a/vbe.c
+++ b/vbe.c
@@ -136,7 +136,7 @@ static int vbe_check_vbe_info(hd_data_t *hd_data)
 }
 
 /* Get EDID info. */
-int vbe_get_edid_info(hd_data_t *hd_data, char *edid)
+int vbe_get_edid_info(hd_data_t *hd_data, char *edid, int port)
 {
   int i;
   int ax, bx, cx;
@@ -144,7 +144,7 @@ int vbe_get_edid_info(hd_data_t *hd_data, char *edid)
   /* Setup registers for the interrupt call */
   ax = 0x4f15;
   bx = 1;
-  cx = 0;
+  cx = port;
 
   /* Get EDID block */
   i = CallInt10(&ax, &bx, &cx, edid, 256, hd_data->flags.cpuemu) & 0xffff;
@@ -211,7 +211,7 @@ static int vbe_check_vbe_info__old(void)
   return 1;
 }
 
-static int vbe_get_edid_info__old(char *edid)
+static int vbe_get_edid_info__old(char *edid, int port)
 {
   int i;
   unsigned char *mem;
@@ -236,6 +236,7 @@ static int vbe_get_edid_info__old(char *edid)
   memset(&regs, 0, sizeof(regs));
   regs.eax = 0x4f15;
   regs.ebx = 0x0001;
+  regs.ecx = port;
   regs.es = ((u_int32_t)mem) >> 4;
   regs.edi = ((u_int32_t)mem) & 0x0f;
 
@@ -261,7 +262,7 @@ static int vbe_get_edid_info__old(char *edid)
   return 1;
 }
 
-int get_edid__old(char *edid)
+int get_edid__old(char *edid, int port)
 {
   int ok;
   /* try with older lrmi interface, we can assume a failure for
@@ -269,12 +270,12 @@ int get_edid__old(char *edid)
   log_err("Retrying with old LRMI interface\n");
   ok = 
     (box_is_xbox() || vbe_check_vbe_info__old()) &&
-    vbe_get_edid_info__old(edid);
+    vbe_get_edid_info__old(edid, port);
   return ok;
 }
 #endif
 
-int get_edid(hd_data_t *hd_data, char *edid)
+int get_edid(hd_data_t *hd_data, char *edid, int port)
 {
   int ok = 0;
 
@@ -286,14 +287,14 @@ int get_edid(hd_data_t *hd_data, char *edid)
   if (!box_is_xbox()) {
 	if (InitInt10(hd_data) == 0) {
 	  ok = vbe_check_vbe_info(hd_data)
-		&& vbe_get_edid_info(hd_data, edid);
+		&& vbe_get_edid_info(hd_data, edid, port);
 	  FreeInt10();
 	}
   }
 
 #ifdef LRMI
   if (!ok)
-	ok = get_edid__old(edid);
+	ok = get_edid__old(edid, port);
 #endif
 
   return ok ? 128 : 0;