staging: speakup: add functions to register and unregister ldisc

This patch adds the above two functions and makes them available to
main.c where they will be called during init and exit functions of
main speakup module. Following patch will make use of them.
Signed-off-by: NOkash Khawaja <okash.khawaja@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/speakup/spk_priv.h

@@ -48,6 +48,8 @@ void spk_stop_serial_interrupt(void);
 int spk_wait_for_xmitr(struct spk_synth *in_synth);
 void spk_serial_release(void);
 void spk_ttyio_release(void);
+void spk_ttyio_register_ldisc(void);
+void spk_ttyio_unregister_ldisc(void);
 
 void synth_buffer_skip_nonlatin1(void);
 u16 synth_buffer_getc(void);

drivers/staging/speakup/spk_ttyio.c

@@ -200,6 +200,18 @@ static int spk_ttyio_initialise_ldisc(struct spk_synth *synth)
 	return ret;
 }
 
+void spk_ttyio_register_ldisc(void)
+{
+	if (tty_register_ldisc(N_SPEAKUP, &spk_ttyio_ldisc_ops))
+		pr_warn("speakup: Error registering line discipline. Most synths won't work.\n");
+}
+
+void spk_ttyio_unregister_ldisc(void)
+{
+	if (tty_unregister_ldisc(N_SPEAKUP))
+		pr_warn("speakup: Couldn't unregister ldisc\n");
+}
+
 static int spk_ttyio_out(struct spk_synth *in_synth, const char ch)
 {
 	if (in_synth->alive && speakup_tty && speakup_tty->ops->write) {