[PATCH 24/35] tty: make tty_buffer_space_avail return uint

From: Jiri Slaby
Date: Wed May 05 2021 - 05:20:53 EST


tty_buffer_space_avail returns values >= 0, so make it clear by the
return type.

Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
Cc: Joel Stanley <joel@xxxxxxxxx>
---
drivers/tty/serial/8250/8250_aspeed_vuart.c | 4 ++--
drivers/tty/tty_buffer.c | 2 +-
include/linux/tty_flip.h | 2 +-
3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_aspeed_vuart.c b/drivers/tty/serial/8250/8250_aspeed_vuart.c
index 61550f24a2d3..92d9a6164dfa 100644
--- a/drivers/tty/serial/8250/8250_aspeed_vuart.c
+++ b/drivers/tty/serial/8250/8250_aspeed_vuart.c
@@ -320,7 +320,7 @@ static int aspeed_vuart_handle_irq(struct uart_port *port)
{
struct uart_8250_port *up = up_to_u8250p(port);
unsigned int iir, lsr;
- int space, count;
+ unsigned int space, count;

iir = serial_port_in(port, UART_IIR);

@@ -346,7 +346,7 @@ static int aspeed_vuart_handle_irq(struct uart_port *port)
}

} else {
- count = min(space, 256);
+ count = min(space, 256U);

do {
serial8250_read_char(up, lsr);
diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c
index 55b1f1711341..585a19f65284 100644
--- a/drivers/tty/tty_buffer.c
+++ b/drivers/tty/tty_buffer.c
@@ -88,7 +88,7 @@ EXPORT_SYMBOL_GPL(tty_buffer_unlock_exclusive);
* pre-allocate if memory guarantee is required).
*/

-int tty_buffer_space_avail(struct tty_port *port)
+unsigned int tty_buffer_space_avail(struct tty_port *port)
{
int space = port->buf.mem_limit - atomic_read(&port->buf.mem_used);
return max(space, 0);
diff --git a/include/linux/tty_flip.h b/include/linux/tty_flip.h
index 767f62086bd9..d6729281ec50 100644
--- a/include/linux/tty_flip.h
+++ b/include/linux/tty_flip.h
@@ -3,7 +3,7 @@
#define _LINUX_TTY_FLIP_H

extern int tty_buffer_set_limit(struct tty_port *port, int limit);
-extern int tty_buffer_space_avail(struct tty_port *port);
+extern unsigned int tty_buffer_space_avail(struct tty_port *port);
extern int tty_buffer_request_room(struct tty_port *port, size_t size);
extern int tty_insert_flip_string_flags(struct tty_port *port,
const unsigned char *chars, const char *flags, size_t size);
--
2.31.1