+/*
+ * QinHeng CH345 is buggy: every second packet inside a SysEx has not CIN 4
+ * but the previously seen CIN, but still with three data bytes.
+ */
+static void ch345_broken_sysex_input(struct snd_usb_midi_in_endpoint *ep,
+ uint8_t *buffer, int buffer_length)
+{
+ unsigned int i, cin, length;
+
+ for (i = 0; i + 3 < buffer_length; i += 4) {
+ if (buffer[i] == 0 && i > 0)
+ break;
+ cin = buffer[i] & 0x0f;
+ if (ep->in_sysex &&
+ cin == ep->last_cin &&
+ (buffer[i + 1 + (cin == 0x6)] & 0x80) == 0)
+ cin = 0x4;
+#if 0
+ if (buffer[i + 1] == 0x90) {
+ /*
+ * Either a corrupted running status or a real note-on
+ * message; impossible to detect reliably.
+ */
+ }
+#endif
+ length = snd_usbmidi_cin_length[cin];
+ snd_usbmidi_input_data(ep, 0, &buffer[i + 1], length);
+ ep->in_sysex = cin == 0x4;
+ if (!ep->in_sysex)
+ ep->last_cin = cin;
+ }
+}
+