tty/serial: lay the foundations for the next set of reworks

- Stop drivers calling their own flush method indirectly, it obfuscates code
  and it will change soon anyway

- A few more lock_kernel paths temporarily needed in some driver internal
  waiting code

- Remove private put_char method that does a write call for one char - we
  have that anyway

- Most but not yet all of the termios copy under lock fixing (some has other
  dependencies to follow)

- Note a few locking bugs in drivers found in the process

- Kill remaining [ab]users of TIOCG/SSOFTCAR in the driver, these must go to
  fix the termios locking

Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 11 deletions

diff --git a/drivers/char/nozomi.c b/drivers/char/nozomi.c
index 6a6843a..b55c933 100644
--- a/drivers/char/nozomi.c
+++ b/drivers/char/nozomi.c
@@ -1724,6 +1724,8 @@ static int ntty_tiocmget(struct tty_struct *tty, struct file *file)
 	const struct ctrl_dl *ctrl_dl = &port->ctrl_dl;
 	const struct ctrl_ul *ctrl_ul = &port->ctrl_ul;
 
+	/* Note: these could change under us but it is not clear this
+	   matters if so */
 	return	(ctrl_ul->RTS ? TIOCM_RTS : 0) |
 		(ctrl_ul->DTR ? TIOCM_DTR : 0) |
 		(ctrl_dl->DCD ? TIOCM_CAR : 0) |
@@ -1849,16 +1851,6 @@ static void ntty_throttle(struct tty_struct *tty)
 	spin_unlock_irqrestore(&dc->spin_mutex, flags);
 }
 
-/* just to discard single character writes */
-static void ntty_put_char(struct tty_struct *tty, unsigned char c)
-{
-	/*
-	 * card does not react correct when we write single chars
-	 * to the card, so we discard them
-	 */
-	DBG2("PUT CHAR Function: %c", c);
-}
-
 /* Returns number of chars in buffer, called by tty layer */
 static s32 ntty_chars_in_buffer(struct tty_struct *tty)
 {
@@ -1892,7 +1884,6 @@ static const struct tty_operations tty_ops = {
 	.unthrottle = ntty_unthrottle,
 	.throttle = ntty_throttle,
 	.chars_in_buffer = ntty_chars_in_buffer,
-	.put_char = ntty_put_char,
 	.tiocmget = ntty_tiocmget,
 	.tiocmset = ntty_tiocmset,
 };