When the platform bus sets the platform_device id to -1 (PLATFORM_DEVID_NONE),
use an incrementing counter for the TTY index instead
Signed-off-by: NGreg Hackmann <ghackmann@google.com>
Signed-off-by: NJin Qian <jinqian@android.com>
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>