Merge branch 'simpledrm-enumeration' into 'main'

ply-device-manager: Treat SimpleDRM drm devices as fbdev devices

Closes #167

See merge request plymouth/plymouth!163

src/libply-splash-core/ply-device-manager.c

@@ -405,6 +405,40 @@ on_drm_udev_add_or_change (ply_device_manager_t *manager,
         }
 }
 
+static bool
+verify_drm_device (struct udev_device *device)
+{
+        const char *id_path;
+
+        /*
+         * Simple-framebuffer devices driven by simpledrm lack information
+         * like panel-rotation info and physical size, causing the splash
+         * to briefly render on its side / without HiDPI scaling, switching
+         * to the correct rendering when the native driver loads.
+         * To avoid this treat simpledrm devices as fbdev devices and only
+         * use them after the timeout.
+         */
+        id_path = udev_device_get_property_value (device, "ID_PATH");
+        if (!ply_string_has_prefix (id_path, "platform-simple-framebuffer"))
+                return true; /* Not a SimpleDRM device */
+
+        /*
+         * With nomodeset, no native drivers will load, so SimpleDRM devices
+         * should be used immediately.
+         */
+        if (ply_kernel_command_line_has_argument ("nomodeset"))
+                return true;
+
+        /*
+         * Some firmwares leave the panel black at boot. Allow enabling SimpleDRM
+         * use from the cmdline to show something to the user ASAP.
+         */
+        if (ply_kernel_command_line_has_argument ("plymouth.use-simpledrm"))
+                return true;
+
+        return false;
+}
+
 static bool
 verify_add_or_change (ply_device_manager_t *manager,
                       const char           *action,
@@ -423,6 +457,11 @@ verify_add_or_change (ply_device_manager_t *manager,
                         ply_trace ("ignoring since we're already using text splash for local console");
                         return false;
                 }
+
+                if (!verify_drm_device (device)) {
+                        ply_trace ("ignoring since we only handle SimpleDRM devices after timeout");
+                        return false;
+                }
         } else {
                 ply_trace ("ignoring since we only handle subsystem %s devices after timeout", subsystem);
                 return false;

src/libply/ply-utils.c

@@ -459,6 +459,15 @@ ply_free_string_array (char **array)
         free (array);
 }
 
+bool
+ply_string_has_prefix (const char *str, const char *prefix)
+{
+        if (str == NULL || prefix == NULL)
+                return false;
+
+        return strncmp (str, prefix, strlen (prefix)) == 0;
+}
+
 double
 ply_get_timestamp (void)
 {

src/libply/ply-utils.h

@@ -85,6 +85,7 @@ bool ply_fd_has_data (int fd);
 bool ply_set_fd_as_blocking (int fd);
 char **ply_copy_string_array (const char *const *array);
 void ply_free_string_array (char **array);
+bool ply_string_has_prefix (const char *str, const char *prefix);
 double ply_get_timestamp (void);
 
 void ply_save_errno (void);