xf86drm: drop control nodes implementation

Drop support for control nodes. The kernel never returns such
nodes. Stop trying to detect and handle them, and always return
an error when a caller tries to open them.

The header is left untouched to avoid breaking libdrm's API.

Signed-off-by: Simon Ser <contact@emersion.fr>

xf86drm.c

@@ -829,8 +829,6 @@ static const char *drmGetDeviceName(int type)
     switch (type) {
     case DRM_NODE_PRIMARY:
         return DRM_DEV_NAME;
-    case DRM_NODE_CONTROL:
-        return DRM_CONTROL_DEV_NAME;
     case DRM_NODE_RENDER:
         return DRM_RENDER_DEV_NAME;
     }
@@ -1026,8 +1024,6 @@ static int drmGetMinorBase(int type)
     switch (type) {
     case DRM_NODE_PRIMARY:
         return 0;
-    case DRM_NODE_CONTROL:
-        return 64;
     case DRM_NODE_RENDER:
         return 128;
     default:
@@ -1048,8 +1044,6 @@ static int drmGetMinorType(int major, int minor)
         // If not in /dev/drm/ we have the type in the name
         if (sscanf(name, "dri/card%d\n", &id) >= 1)
            return DRM_NODE_PRIMARY;
-        else if (sscanf(name, "dri/control%d\n", &id) >= 1)
-           return DRM_NODE_CONTROL;
         else if (sscanf(name, "dri/renderD%d\n", &id) >= 1)
            return DRM_NODE_RENDER;
         return -1;
@@ -1064,7 +1058,6 @@ static int drmGetMinorType(int major, int minor)
 
     switch (type) {
     case DRM_NODE_PRIMARY:
-    case DRM_NODE_CONTROL:
     case DRM_NODE_RENDER:
         return type;
     default:
@@ -1077,8 +1070,6 @@ static const char *drmGetMinorName(int type)
     switch (type) {
     case DRM_NODE_PRIMARY:
         return DRM_PRIMARY_MINOR_NAME;
-    case DRM_NODE_CONTROL:
-        return DRM_CONTROL_MINOR_NAME;
     case DRM_NODE_RENDER:
         return DRM_RENDER_MINOR_NAME;
     default:
@@ -1265,7 +1256,7 @@ drm_public int drmOpen(const char *name, const char *busid)
  *
  * \param name driver name. Not referenced if bus ID is supplied.
  * \param busid bus ID. Zero if not known.
- * \param type the device node type to open, PRIMARY, CONTROL or RENDER
+ * \param type the device node type to open, PRIMARY or RENDER
  *
  * \return a file descriptor on success, or a negative value on error.
  *
@@ -1298,7 +1289,7 @@ drm_public int drmOpenWithType(const char *name, const char *busid, int type)
 
 drm_public int drmOpenControl(int minor)
 {
-    return drmOpenMinor(minor, 0, DRM_NODE_CONTROL);
+    return -EINVAL;
 }
 
 drm_public int drmOpenRender(int minor)
@@ -3704,9 +3695,6 @@ static int get_sysctl_pci_bus_info(int maj, int min, drmPciBusInfoPtr info)
     switch (type) {
     case DRM_NODE_PRIMARY:
          break;
-    case DRM_NODE_CONTROL:
-         id -= 64;
-         break;
     case DRM_NODE_RENDER:
          id -= 128;
          break;
@@ -3821,10 +3809,6 @@ drm_public int drmDevicesEqual(drmDevicePtr a, drmDevicePtr b)
 
 static int drmGetNodeType(const char *name)
 {
-    if (strncmp(name, DRM_CONTROL_MINOR_NAME,
-        sizeof(DRM_CONTROL_MINOR_NAME ) - 1) == 0)
-        return DRM_NODE_CONTROL;
-
     if (strncmp(name, DRM_RENDER_MINOR_NAME,
         sizeof(DRM_RENDER_MINOR_NAME) - 1) == 0)
         return DRM_NODE_RENDER;

xf86drm.h

@@ -79,18 +79,18 @@ extern "C" {
 #ifdef __OpenBSD__
 #define DRM_DIR_NAME  "/dev"
 #define DRM_PRIMARY_MINOR_NAME  "drm"
-#define DRM_CONTROL_MINOR_NAME  "drmC"
+#define DRM_CONTROL_MINOR_NAME  "drmC" /* deprecated */
 #define DRM_RENDER_MINOR_NAME   "drmR"
 #else
 #define DRM_DIR_NAME  "/dev/dri"
 #define DRM_PRIMARY_MINOR_NAME  "card"
-#define DRM_CONTROL_MINOR_NAME  "controlD"
+#define DRM_CONTROL_MINOR_NAME  "controlD" /* deprecated */
 #define DRM_RENDER_MINOR_NAME   "renderD"
 #define DRM_PROC_NAME "/proc/dri/" /* For backward Linux compatibility */
 #endif
 
 #define DRM_DEV_NAME          "%s/" DRM_PRIMARY_MINOR_NAME "%d"
-#define DRM_CONTROL_DEV_NAME  "%s/" DRM_CONTROL_MINOR_NAME "%d"
+#define DRM_CONTROL_DEV_NAME  "%s/" DRM_CONTROL_MINOR_NAME "%d" /* deprecated */
 #define DRM_RENDER_DEV_NAME   "%s/" DRM_RENDER_MINOR_NAME  "%d"
 
 #define DRM_NODE_NAME_MAX \
@@ -596,14 +596,14 @@ extern int           drmAvailable(void);
 extern int           drmOpen(const char *name, const char *busid);
 
 #define DRM_NODE_PRIMARY 0
-#define DRM_NODE_CONTROL 1
+#define DRM_NODE_CONTROL 1 /* deprecated: never returned */
 #define DRM_NODE_RENDER  2
 #define DRM_NODE_MAX     3
 
 extern int           drmOpenWithType(const char *name, const char *busid,
                                      int type);
 
-extern int           drmOpenControl(int minor);
+extern int           drmOpenControl(int minor); /* deprecated: always fails */
 extern int           drmOpenRender(int minor);
 extern int           drmClose(int fd);
 extern drmVersionPtr drmGetVersion(int fd);
@@ -808,7 +808,7 @@ extern int drmHandleEvent(int fd, drmEventContextPtr evctx);
 extern char *drmGetDeviceNameFromFd(int fd);
 
 /* Improved version of drmGetDeviceNameFromFd which attributes for any type of
- * device/node - card, control or renderD.
+ * device/node - card or renderD.
  */
 extern char *drmGetDeviceNameFromFd2(int fd);
 extern int drmGetNodeTypeFromFd(int fd);