tty: make tty_operations::send_xchar accept u8 char

tty_operations::send_xchar is one of the last users of 'char' type for
characters in the tty layer. Convert it to u8 now.

Signed-off-by: "Jiri Slaby (SUSE)" <[e-mail]>
Cc: Karsten Keil <[e-mail]>
Cc: Ulf Hansson <[e-mail]>
Cc: Marcel Holtmann <[e-mail]>
Cc: Johan Hedberg <[e-mail]>
Cc: Luiz Augusto von Dentz <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Reviewed-by: Geert Uytterhoeven <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/isdn/capi/capi.c

···
 	tty_port_hangup(&mp->port);
 }
 
-static void capinc_tty_send_xchar(struct tty_struct *tty, char ch)
+static void capinc_tty_send_xchar(struct tty_struct *tty, u8 ch)
 {
-	pr_debug("capinc_tty_send_xchar(%d)\n", ch);
+	pr_debug("capinc_tty_send_xchar(%u)\n", ch);
 }
 
 static const struct tty_operations capinc_ops = {

drivers/mmc/core/sdio_uart.c

···
 	return kfifo_len(&port->xmit_fifo);
 }
 
-static void sdio_uart_send_xchar(struct tty_struct *tty, char ch)
+static void sdio_uart_send_xchar(struct tty_struct *tty, u8 ch)
 {
 	struct sdio_uart_port *port = tty->driver_data;
 

drivers/tty/amiserial.c

···
  * This function is used to send a high-priority XON/XOFF character to
  * the device
  */
-static void rs_send_xchar(struct tty_struct *tty, char ch)
+static void rs_send_xchar(struct tty_struct *tty, u8 ch)
 {
 	struct serial_state *info = tty->driver_data;
         unsigned long flags;

drivers/tty/serial/serial_core.c

···
  * This function is used to send a high-priority XON/XOFF character to
  * the device
  */
-static void uart_send_xchar(struct tty_struct *tty, char ch)
+static void uart_send_xchar(struct tty_struct *tty, u8 ch)
 {
 	struct uart_state *state = tty->driver_data;
 	struct uart_port *port;

drivers/tty/tty_io.c

···
  *
  * Locking: none for xchar method, write ordering for write method.
  */
-int tty_send_xchar(struct tty_struct *tty, char ch)
+int tty_send_xchar(struct tty_struct *tty, u8 ch)
 {
 	bool was_stopped = tty->flow.stopped;
 

include/linux/tty.h

···
 void stop_tty(struct tty_struct *tty);
 void start_tty(struct tty_struct *tty);
 void tty_write_message(struct tty_struct *tty, char *msg);
-int tty_send_xchar(struct tty_struct *tty, char ch);
+int tty_send_xchar(struct tty_struct *tty, u8 ch);
 int tty_put_char(struct tty_struct *tty, unsigned char c);
 unsigned int tty_chars_in_buffer(struct tty_struct *tty);
 unsigned int tty_write_room(struct tty_struct *tty);

include/linux/tty_driver.h

···
  *	Optional: If not provided, the device is assumed to have no FIFO.
  *	Usually correct to invoke via tty_wait_until_sent(). May sleep.
  *
- * @send_xchar: ``void ()(struct tty_struct *tty, char ch)``
+ * @send_xchar: ``void ()(struct tty_struct *tty, u8 ch)``
  *
  *	This routine is used to send a high-priority XON/XOFF character (@ch)
  *	to the @tty device.
···
 	void (*flush_buffer)(struct tty_struct *tty);
 	void (*set_ldisc)(struct tty_struct *tty);
 	void (*wait_until_sent)(struct tty_struct *tty, int timeout);
-	void (*send_xchar)(struct tty_struct *tty, char ch);
+	void (*send_xchar)(struct tty_struct *tty, u8 ch);
 	int (*tiocmget)(struct tty_struct *tty);
 	int (*tiocmset)(struct tty_struct *tty,
 			unsigned int set, unsigned int clear);

net/bluetooth/rfcomm/tty.c

···
 	tty_wakeup(tty);
 }
 
-static void rfcomm_tty_send_xchar(struct tty_struct *tty, char ch)
+static void rfcomm_tty_send_xchar(struct tty_struct *tty, u8 ch)
 {
 	BT_DBG("tty %p ch %c", tty, ch);
 }