[PATCH 00/11] TTY patches for 5.18

[PATCH 00/11] TTY patches for 5.18

[Jiri Slaby]

These are small random cleanups and improvements I came across while
doing larger cleanups which are not finished yet. So flushing only these
from my queue at this very moment for 5.18.

Jiri Slaby (11):
  serial: core: clean up EXPORT_SYMBOLs
  serial: atmel_serial: include circ_buf.h
  tty: add kfifo to tty_port
  tty: tty_port_open, document shutdown vs failed activate
  mxser: fix xmit_buf leak in activate when LSR == 0xff
  mxser: use tty_port xmit_buf helpers
  mxser: switch from xmit_buf to kfifo
  serial: fsl_linflexuart: deduplicate character sending
  serial: fsl_linflexuart: don't call uart_write_wakeup() twice
  serial: make uart_console_write->putchar()'s character a char
  serial: mcf: use helpers in mcf_tx_chars()

 drivers/tty/goldfish.c                     |   2 +-
 drivers/tty/hvc/hvc_dcc.c                  |   2 +-
 drivers/tty/mxser.c                        | 109 +++++++++------------
 drivers/tty/serial/21285.c                 |   2 +-
 drivers/tty/serial/8250/8250_early.c       |   2 +-
 drivers/tty/serial/8250/8250_ingenic.c     |   2 +-
 drivers/tty/serial/8250/8250_port.c        |   2 +-
 drivers/tty/serial/altera_jtaguart.c       |   4 +-
 drivers/tty/serial/altera_uart.c           |   2 +-
 drivers/tty/serial/amba-pl010.c            |   2 +-
 drivers/tty/serial/amba-pl011.c            |   6 +-
 drivers/tty/serial/apbuart.c               |   2 +-
 drivers/tty/serial/ar933x_uart.c           |   2 +-
 drivers/tty/serial/arc_uart.c              |   2 +-
 drivers/tty/serial/atmel_serial.c          |   3 +-
 drivers/tty/serial/bcm63xx_uart.c          |   2 +-
 drivers/tty/serial/clps711x.c              |   2 +-
 drivers/tty/serial/digicolor-usart.c       |   2 +-
 drivers/tty/serial/dz.c                    |   2 +-
 drivers/tty/serial/earlycon-arm-semihost.c |   2 +-
 drivers/tty/serial/earlycon-riscv-sbi.c    |   2 +-
 drivers/tty/serial/fsl_linflexuart.c       |  50 ++++------
 drivers/tty/serial/fsl_lpuart.c            |   4 +-
 drivers/tty/serial/imx.c                   |   2 +-
 drivers/tty/serial/imx_earlycon.c          |   2 +-
 drivers/tty/serial/ip22zilog.c             |   2 +-
 drivers/tty/serial/lantiq.c                |   2 +-
 drivers/tty/serial/liteuart.c              |   2 +-
 drivers/tty/serial/lpc32xx_hs.c            |   2 +-
 drivers/tty/serial/mcf.c                   |   7 +-
 drivers/tty/serial/meson_uart.c            |   2 +-
 drivers/tty/serial/milbeaut_usio.c         |   2 +-
 drivers/tty/serial/mps2-uart.c             |   4 +-
 drivers/tty/serial/mvebu-uart.c            |   4 +-
 drivers/tty/serial/mxs-auart.c             |   2 +-
 drivers/tty/serial/omap-serial.c           |   2 +-
 drivers/tty/serial/owl-uart.c              |   2 +-
 drivers/tty/serial/pch_uart.c              |   2 +-
 drivers/tty/serial/pic32_uart.c            |   2 +-
 drivers/tty/serial/pmac_zilog.c            |   2 +-
 drivers/tty/serial/pxa.c                   |   2 +-
 drivers/tty/serial/qcom_geni_serial.c      |   2 +-
 drivers/tty/serial/rda-uart.c              |   2 +-
 drivers/tty/serial/sa1100.c                |   2 +-
 drivers/tty/serial/samsung_tty.c           |   4 +-
 drivers/tty/serial/sb1250-duart.c          |   2 +-
 drivers/tty/serial/sccnxp.c                |   2 +-
 drivers/tty/serial/serial_core.c           |  20 ++--
 drivers/tty/serial/serial_txx9.c           |   2 +-
 drivers/tty/serial/sh-sci.c                |   2 +-
 drivers/tty/serial/sifive.c                |   4 +-
 drivers/tty/serial/sprd_serial.c           |   2 +-
 drivers/tty/serial/st-asc.c                |   2 +-
 drivers/tty/serial/stm32-usart.c           |   2 +-
 drivers/tty/serial/sunsu.c                 |   2 +-
 drivers/tty/serial/sunzilog.c              |   4 +-
 drivers/tty/serial/uartlite.c              |   4 +-
 drivers/tty/serial/vr41xx_siu.c            |   2 +-
 drivers/tty/serial/vt8500_serial.c         |   2 +-
 drivers/tty/serial/xilinx_uartps.c         |   2 +-
 drivers/tty/serial/zs.c                    |   2 +-
 drivers/tty/tty_port.c                     |   9 +-
 include/linux/serial_core.h                |   2 +-
 include/linux/tty_port.h                   |   3 +
 64 files changed, 155 insertions(+), 180 deletions(-)

-- 
2.34.1

[PATCH 01/11] serial: core: clean up EXPORT_SYMBOLs

[Jiri Slaby]

Some EXPORT_SYMBOLs are grouped at one location. Some follow functions
they export, but a newline is present before them. Fix all these and
move them where they belong.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/tty/serial/serial_core.c | 18 +++++++-----------
 1 file changed, 7 insertions(+), 11 deletions(-)

diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index dc40c4155356..1f6df577c75b 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -105,6 +105,7 @@ void uart_write_wakeup(struct uart_port *port)
 	BUG_ON(!state);
 	tty_port_tty_wakeup(&state->port);
 }
+EXPORT_SYMBOL(uart_write_wakeup);
 
 static void uart_stop(struct tty_struct *tty)
 {
@@ -351,7 +352,6 @@ uart_update_timeout(struct uart_port *port, unsigned int cflag,
 	 */
 	port->timeout = (HZ * size) / baud + HZ/50;
 }
-
 EXPORT_SYMBOL(uart_update_timeout);
 
 /**
@@ -453,7 +453,6 @@ uart_get_baud_rate(struct uart_port *port, struct ktermios *termios,
 	WARN_ON(1);
 	return 0;
 }
-
 EXPORT_SYMBOL(uart_get_baud_rate);
 
 /**
@@ -478,7 +477,6 @@ uart_get_divisor(struct uart_port *port, unsigned int baud)
 
 	return quot;
 }
-
 EXPORT_SYMBOL(uart_get_divisor);
 
 /* Caller holds port mutex */
@@ -2220,6 +2218,7 @@ int uart_suspend_port(struct uart_driver *drv, struct uart_port *uport)
 
 	return 0;
 }
+EXPORT_SYMBOL(uart_suspend_port);
 
 int uart_resume_port(struct uart_driver *drv, struct uart_port *uport)
 {
@@ -2305,6 +2304,7 @@ int uart_resume_port(struct uart_driver *drv, struct uart_port *uport)
 
 	return 0;
 }
+EXPORT_SYMBOL(uart_resume_port);
 
 static inline void
 uart_report_port(struct uart_driver *drv, struct uart_port *port)
@@ -2599,6 +2599,7 @@ int uart_register_driver(struct uart_driver *drv)
 out:
 	return retval;
 }
+EXPORT_SYMBOL(uart_register_driver);
 
 /**
  *	uart_unregister_driver - remove a driver from the uart core layer
@@ -2622,6 +2623,7 @@ void uart_unregister_driver(struct uart_driver *drv)
 	drv->state = NULL;
 	drv->tty_driver = NULL;
 }
+EXPORT_SYMBOL(uart_unregister_driver);
 
 struct tty_driver *uart_console_device(struct console *co, int *index)
 {
@@ -2956,6 +2958,7 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport)
 
 	return ret;
 }
+EXPORT_SYMBOL(uart_add_one_port);
 
 /**
  *	uart_remove_one_port - detach a driver defined port structure
@@ -3036,6 +3039,7 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *uport)
 
 	return ret;
 }
+EXPORT_SYMBOL(uart_remove_one_port);
 
 /*
  *	Are the two ports equivalent?
@@ -3212,14 +3216,6 @@ bool uart_try_toggle_sysrq(struct uart_port *port, unsigned int ch)
 EXPORT_SYMBOL_GPL(uart_try_toggle_sysrq);
 #endif
 
-EXPORT_SYMBOL(uart_write_wakeup);
-EXPORT_SYMBOL(uart_register_driver);
-EXPORT_SYMBOL(uart_unregister_driver);
-EXPORT_SYMBOL(uart_suspend_port);
-EXPORT_SYMBOL(uart_resume_port);
-EXPORT_SYMBOL(uart_add_one_port);
-EXPORT_SYMBOL(uart_remove_one_port);
-
 /**
  * uart_get_rs485_mode() - retrieve rs485 properties for given uart
  * @port: uart device's target port
-- 
2.34.1

[PATCH 02/11] serial: atmel_serial: include circ_buf.h

[Jiri Slaby]

atmel_uart_port::rx_ring is defined as struct circ_buf, but circ_buf.h
is not included explicitly in atmel_serial.c. It is included only
implicitly via serial_core.h. Fix this as serial_core.h might not
include that header in the future.

Signed-off-by:Jiri Slaby <jslaby@suse.cz>
Cc: Richard Genoud <richard.genoud@gmail.com>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
---
 drivers/tty/serial/atmel_serial.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index c370eddc651b..2d09a89974a2 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -8,6 +8,7 @@
  *
  *  DMA support added by Chip Coldwell.
  */
+#include <linux/circ_buf.h>
 #include <linux/tty.h>
 #include <linux/ioport.h>
 #include <linux/slab.h>
-- 
2.34.1

Re: [PATCH 02/11] serial: atmel_serial: include circ_buf.h

[Richard Genoud]

Le 24/01/2022 à 08:14, Jiri Slaby a écrit :
> atmel_uart_port::rx_ring is defined as struct circ_buf, but circ_buf.h
> is not included explicitly in atmel_serial.c. It is included only
> implicitly via serial_core.h. Fix this as serial_core.h might not
> include that header in the future.
> 
> Signed-off-by:Jiri Slaby <jslaby@suse.cz>
> Cc: Richard Genoud <richard.genoud@gmail.com>
> Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
> Cc: Ludovic Desroches <ludovic.desroches@microchip.com>

Signed-off-by: Richard Genoud <richard.genoud@gmail.com>

> ---
>   drivers/tty/serial/atmel_serial.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
> index c370eddc651b..2d09a89974a2 100644
> --- a/drivers/tty/serial/atmel_serial.c
> +++ b/drivers/tty/serial/atmel_serial.c
> @@ -8,6 +8,7 @@
>    *
>    *  DMA support added by Chip Coldwell.
>    */
> +#include <linux/circ_buf.h>
>   #include <linux/tty.h>
>   #include <linux/ioport.h>
>   #include <linux/slab.h>
Thanks !

Re: [PATCH 02/11] serial: atmel_serial: include circ_buf.h

[Richard Genoud]

Le 24/01/2022 à 09:46, Richard Genoud a écrit :
> 
> Le 24/01/2022 à 08:14, Jiri Slaby a écrit :
>> atmel_uart_port::rx_ring is defined as struct circ_buf, but circ_buf.h
>> is not included explicitly in atmel_serial.c. It is included only
>> implicitly via serial_core.h. Fix this as serial_core.h might not
>> include that header in the future.
>>
>> Signed-off-by:Jiri Slaby <jslaby@suse.cz>
>> Cc: Richard Genoud <richard.genoud@gmail.com>
>> Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
>> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
>> Cc: Ludovic Desroches <ludovic.desroches@microchip.com>

Sorry, I really meant acked-by, not Signed-off-by :
Acked-by: Richard Genoud <richard.genoud@gmail.com>

>> ---
>>   drivers/tty/serial/atmel_serial.c | 1 +
>>   1 file changed, 1 insertion(+)
>>
>> diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
>> index c370eddc651b..2d09a89974a2 100644
>> --- a/drivers/tty/serial/atmel_serial.c
>> +++ b/drivers/tty/serial/atmel_serial.c
>> @@ -8,6 +8,7 @@
>>    *
>>    *  DMA support added by Chip Coldwell.
>>    */
>> +#include <linux/circ_buf.h>
>>   #include <linux/tty.h>
>>   #include <linux/ioport.h>
>>   #include <linux/slab.h>
Thanks !

[PATCH 03/11] tty: add kfifo to tty_port

[Jiri Slaby]

Define a kfifo inside struct tty_port. We use DECLARE_KFIFO_PTR and let
the preexisting tty_port::xmit_buf be also the buffer for the kfifo.
And handle the initialization/decomissioning along with xmit_buf, i.e.
in tty_port_alloc_xmit_buf() and tty_port_free_xmit_buf(), respectively.

This allows for kfifo use in drivers which opt-in, while others still
may use the old xmit_buf. mxser will be the first user in the next
few patches.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/tty/tty_port.c   | 6 +++++-
 include/linux/tty_port.h | 3 +++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/tty_port.c b/drivers/tty/tty_port.c
index 7709ce655f44..7644834640f1 100644
--- a/drivers/tty/tty_port.c
+++ b/drivers/tty/tty_port.c
@@ -225,8 +225,11 @@ int tty_port_alloc_xmit_buf(struct tty_port *port)
 {
 	/* We may sleep in get_zeroed_page() */
 	mutex_lock(&port->buf_mutex);
-	if (port->xmit_buf == NULL)
+	if (port->xmit_buf == NULL) {
 		port->xmit_buf = (unsigned char *)get_zeroed_page(GFP_KERNEL);
+		if (port->xmit_buf)
+			kfifo_init(&port->xmit_fifo, port->xmit_buf, PAGE_SIZE);
+	}
 	mutex_unlock(&port->buf_mutex);
 	if (port->xmit_buf == NULL)
 		return -ENOMEM;
@@ -240,6 +243,7 @@ void tty_port_free_xmit_buf(struct tty_port *port)
 	if (port->xmit_buf != NULL) {
 		free_page((unsigned long)port->xmit_buf);
 		port->xmit_buf = NULL;
+		INIT_KFIFO(port->xmit_fifo);
 	}
 	mutex_unlock(&port->buf_mutex);
 }
diff --git a/include/linux/tty_port.h b/include/linux/tty_port.h
index d3ea9ed0b98e..58e9619116b7 100644
--- a/include/linux/tty_port.h
+++ b/include/linux/tty_port.h
@@ -2,6 +2,7 @@
 #ifndef _LINUX_TTY_PORT_H
 #define _LINUX_TTY_PORT_H
 
+#include <linux/kfifo.h>
 #include <linux/kref.h>
 #include <linux/mutex.h>
 #include <linux/tty_buffer.h>
@@ -67,6 +68,7 @@ extern const struct tty_port_client_operations tty_port_default_client_ops;
  * @mutex: locking, for open, shutdown and other port operations
  * @buf_mutex: @xmit_buf alloc lock
  * @xmit_buf: optional xmit buffer used by some drivers
+ * @xmit_fifo: optional xmit buffer used by some drivers
  * @close_delay: delay in jiffies to wait when closing the port
  * @closing_wait: delay in jiffies for output to be sent before closing
  * @drain_delay: set to zero if no pure time based drain is needed else set to
@@ -110,6 +112,7 @@ struct tty_port {
 	struct mutex		mutex;
 	struct mutex		buf_mutex;
 	unsigned char		*xmit_buf;
+	DECLARE_KFIFO_PTR(xmit_fifo, unsigned char);
 	unsigned int		close_delay;
 	unsigned int		closing_wait;
 	int			drain_delay;
-- 
2.34.1

[PATCH 04/11] tty: tty_port_open, document shutdown vs failed activate

[Jiri Slaby]

Add a note that ->shutdown is not called when ->activate fails. Just so
we are clear.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/tty/tty_port.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/tty/tty_port.c b/drivers/tty/tty_port.c
index 7644834640f1..4282895ede9e 100644
--- a/drivers/tty/tty_port.c
+++ b/drivers/tty/tty_port.c
@@ -736,6 +736,9 @@ EXPORT_SYMBOL_GPL(tty_port_install);
  * the device to be ready using tty_port_block_til_ready() (e.g.  raises
  * DTR/CTS and waits for carrier).
  *
+ * Note that @port->ops->shutdown is not called when @port->ops->activate
+ * returns an error (on the contrary, @tty->ops->close is).
+ *
  * Locking: Caller holds tty lock.
  *
  * Note: may drop and reacquire tty lock (in tty_port_block_til_ready()) so
-- 
2.34.1

[PATCH 05/11] mxser: fix xmit_buf leak in activate when LSR == 0xff

[Jiri Slaby]

When LSR is 0xff in ->activate() (rather unlike), we return an error.
Provided ->shutdown() is not called when ->activate() fails, nothing
actually frees the buffer in this case.

Fix this by properly freeing the buffer in a designated label. We jump
there also from the "!info->type" if now too.

Fixes: 6769140d3047 ("tty: mxser: use the tty_port_open method")
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/tty/mxser.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c
index c858aff721c4..fbb796f83753 100644
--- a/drivers/tty/mxser.c
+++ b/drivers/tty/mxser.c
@@ -744,6 +744,7 @@ static int mxser_activate(struct tty_port *port, struct tty_struct *tty)
 	struct mxser_port *info = container_of(port, struct mxser_port, port);
 	unsigned long page;
 	unsigned long flags;
+	int ret;
 
 	page = __get_free_page(GFP_KERNEL);
 	if (!page)
@@ -753,9 +754,9 @@ static int mxser_activate(struct tty_port *port, struct tty_struct *tty)
 
 	if (!info->type) {
 		set_bit(TTY_IO_ERROR, &tty->flags);
-		free_page(page);
 		spin_unlock_irqrestore(&info->slock, flags);
-		return 0;
+		ret = 0;
+		goto err_free_xmit;
 	}
 	info->port.xmit_buf = (unsigned char *) page;
 
@@ -775,8 +776,10 @@ static int mxser_activate(struct tty_port *port, struct tty_struct *tty)
 		if (capable(CAP_SYS_ADMIN)) {
 			set_bit(TTY_IO_ERROR, &tty->flags);
 			return 0;
-		} else
-			return -ENODEV;
+		}
+
+		ret = -ENODEV;
+		goto err_free_xmit;
 	}
 
 	/*
@@ -821,6 +824,10 @@ static int mxser_activate(struct tty_port *port, struct tty_struct *tty)
 	spin_unlock_irqrestore(&info->slock, flags);
 
 	return 0;
+err_free_xmit:
+	free_page(page);
+	info->port.xmit_buf = NULL;
+	return ret;
 }
 
 /*
-- 
2.34.1

[PATCH 06/11] mxser: use tty_port xmit_buf helpers

[Jiri Slaby]

For the mxser driver to use kfifo, use tty_port_alloc_xmit_buf() and
tty_port_free_xmit_buf() helpers in activate/shutdown, respectively.

As these calls have to be done in a non-atomic context, we have to move
them outside spinlock and make sure irq is really stopped after we write
to the ISR register.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/tty/mxser.c | 24 +++++++++---------------
 1 file changed, 9 insertions(+), 15 deletions(-)

diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c
index fbb796f83753..4ddc12a63666 100644
--- a/drivers/tty/mxser.c
+++ b/drivers/tty/mxser.c
@@ -742,13 +742,12 @@ static void mxser_disable_and_clear_FIFO(struct mxser_port *info)
 static int mxser_activate(struct tty_port *port, struct tty_struct *tty)
 {
 	struct mxser_port *info = container_of(port, struct mxser_port, port);
-	unsigned long page;
 	unsigned long flags;
 	int ret;
 
-	page = __get_free_page(GFP_KERNEL);
-	if (!page)
-		return -ENOMEM;
+	ret = tty_port_alloc_xmit_buf(port);
+	if (ret < 0)
+		return ret;
 
 	spin_lock_irqsave(&info->slock, flags);
 
@@ -758,7 +757,6 @@ static int mxser_activate(struct tty_port *port, struct tty_struct *tty)
 		ret = 0;
 		goto err_free_xmit;
 	}
-	info->port.xmit_buf = (unsigned char *) page;
 
 	/*
 	 * Clear the FIFO buffers and disable them
@@ -825,8 +823,7 @@ static int mxser_activate(struct tty_port *port, struct tty_struct *tty)
 
 	return 0;
 err_free_xmit:
-	free_page(page);
-	info->port.xmit_buf = NULL;
+	tty_port_free_xmit_buf(port);
 	return ret;
 }
 
@@ -862,14 +859,6 @@ static void mxser_shutdown_port(struct tty_port *port)
 	 */
 	wake_up_interruptible(&info->port.delta_msr_wait);
 
-	/*
-	 * Free the xmit buffer, if necessary
-	 */
-	if (info->port.xmit_buf) {
-		free_page((unsigned long) info->port.xmit_buf);
-		info->port.xmit_buf = NULL;
-	}
-
 	info->IER = 0;
 	outb(0x00, info->ioaddr + UART_IER);
 
@@ -884,6 +873,11 @@ static void mxser_shutdown_port(struct tty_port *port)
 		mxser_must_no_sw_flow_control(info->ioaddr);
 
 	spin_unlock_irqrestore(&info->slock, flags);
+
+	/* make sure ISR is not running while we free the buffer */
+	synchronize_irq(info->board->irq);
+
+	tty_port_free_xmit_buf(port);
 }
 
 /*
-- 
2.34.1

[PATCH 07/11] mxser: switch from xmit_buf to kfifo

[Jiri Slaby]

Use kfifo for xmit buffer handling. The change is mostly
straightforward. It saves complexity both on the stuffing side
(mxser_write() and mxser_put_char()) and pulling side
(mxser_transmit_chars()). In fact, the loop in mxser_write() can be
completely deleted as the wrap of the buffer is taken care of in the
kfifo code now.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/tty/mxser.c | 74 +++++++++++++++++----------------------------
 1 file changed, 27 insertions(+), 47 deletions(-)

diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c
index 4ddc12a63666..836c9eca2946 100644
--- a/drivers/tty/mxser.c
+++ b/drivers/tty/mxser.c
@@ -275,9 +275,6 @@ struct mxser_port {
 	u8 read_status_mask;
 	u8 ignore_status_mask;
 	u8 xmit_fifo_size;
-	unsigned int xmit_head;
-	unsigned int xmit_tail;
-	unsigned int xmit_cnt;
 
 	spinlock_t slock;
 };
@@ -813,7 +810,7 @@ static int mxser_activate(struct tty_port *port, struct tty_struct *tty)
 	(void) inb(info->ioaddr + UART_MSR);
 
 	clear_bit(TTY_IO_ERROR, &tty->flags);
-	info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
+	kfifo_reset(&port->xmit_fifo);
 
 	/*
 	 * and set the speed of the serial port
@@ -901,9 +898,8 @@ static void mxser_flush_buffer(struct tty_struct *tty)
 	struct mxser_port *info = tty->driver_data;
 	unsigned long flags;
 
-
 	spin_lock_irqsave(&info->slock, flags);
-	info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
+	kfifo_reset(&info->port.xmit_fifo);
 
 	outb(info->FCR | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
 		info->ioaddr + UART_FCR);
@@ -920,50 +916,34 @@ static void mxser_close(struct tty_struct *tty, struct file *filp)
 
 static int mxser_write(struct tty_struct *tty, const unsigned char *buf, int count)
 {
-	int c, total = 0;
 	struct mxser_port *info = tty->driver_data;
 	unsigned long flags;
+	int written;
+	bool is_empty;
 
-	while (1) {
-		c = min_t(int, count, min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
-					  SERIAL_XMIT_SIZE - info->xmit_head));
-		if (c <= 0)
-			break;
-
-		memcpy(info->port.xmit_buf + info->xmit_head, buf, c);
-		spin_lock_irqsave(&info->slock, flags);
-		info->xmit_head = (info->xmit_head + c) &
-				  (SERIAL_XMIT_SIZE - 1);
-		info->xmit_cnt += c;
-		spin_unlock_irqrestore(&info->slock, flags);
-
-		buf += c;
-		count -= c;
-		total += c;
-	}
+	spin_lock_irqsave(&info->slock, flags);
+	written = kfifo_in(&info->port.xmit_fifo, buf, count);
+	is_empty = kfifo_is_empty(&info->port.xmit_fifo);
+	spin_unlock_irqrestore(&info->slock, flags);
 
-	if (info->xmit_cnt && !tty->flow.stopped)
+	if (!is_empty && !tty->flow.stopped)
 		if (!tty->hw_stopped || mxser_16550A_or_MUST(info))
 			mxser_start_tx(info);
 
-	return total;
+	return written;
 }
 
 static int mxser_put_char(struct tty_struct *tty, unsigned char ch)
 {
 	struct mxser_port *info = tty->driver_data;
 	unsigned long flags;
-
-	if (info->xmit_cnt >= SERIAL_XMIT_SIZE - 1)
-		return 0;
+	int ret;
 
 	spin_lock_irqsave(&info->slock, flags);
-	info->port.xmit_buf[info->xmit_head++] = ch;
-	info->xmit_head &= SERIAL_XMIT_SIZE - 1;
-	info->xmit_cnt++;
+	ret = kfifo_put(&info->port.xmit_fifo, ch);
 	spin_unlock_irqrestore(&info->slock, flags);
 
-	return 1;
+	return ret;
 }
 
 
@@ -971,7 +951,7 @@ static void mxser_flush_chars(struct tty_struct *tty)
 {
 	struct mxser_port *info = tty->driver_data;
 
-	if (!info->xmit_cnt || tty->flow.stopped ||
+	if (kfifo_is_empty(&info->port.xmit_fifo) || tty->flow.stopped ||
 			(tty->hw_stopped && !mxser_16550A_or_MUST(info)))
 		return;
 
@@ -981,16 +961,15 @@ static void mxser_flush_chars(struct tty_struct *tty)
 static unsigned int mxser_write_room(struct tty_struct *tty)
 {
 	struct mxser_port *info = tty->driver_data;
-	int ret;
 
-	ret = SERIAL_XMIT_SIZE - info->xmit_cnt - 1;
-	return ret < 0 ? 0 : ret;
+	return kfifo_avail(&info->port.xmit_fifo);
 }
 
 static unsigned int mxser_chars_in_buffer(struct tty_struct *tty)
 {
 	struct mxser_port *info = tty->driver_data;
-	return info->xmit_cnt;
+
+	return kfifo_len(&info->port.xmit_fifo);
 }
 
 /*
@@ -1379,7 +1358,7 @@ static void mxser_start(struct tty_struct *tty)
 	unsigned long flags;
 
 	spin_lock_irqsave(&info->slock, flags);
-	if (info->xmit_cnt)
+	if (!kfifo_is_empty(&info->port.xmit_fifo))
 		__mxser_start_tx(info);
 	spin_unlock_irqrestore(&info->slock, flags);
 }
@@ -1610,7 +1589,7 @@ static void mxser_transmit_chars(struct tty_struct *tty, struct mxser_port *port
 		return;
 	}
 
-	if (!port->xmit_cnt || tty->flow.stopped ||
+	if (kfifo_is_empty(&port->port.xmit_fifo) || tty->flow.stopped ||
 			(tty->hw_stopped && !mxser_16550A_or_MUST(port))) {
 		__mxser_stop_tx(port);
 		return;
@@ -1618,18 +1597,19 @@ static void mxser_transmit_chars(struct tty_struct *tty, struct mxser_port *port
 
 	count = port->xmit_fifo_size;
 	do {
-		outb(port->port.xmit_buf[port->xmit_tail++],
-			port->ioaddr + UART_TX);
-		port->xmit_tail &= SERIAL_XMIT_SIZE - 1;
-		port->icount.tx++;
-		if (!--port->xmit_cnt)
+		unsigned char c;
+
+		if (!kfifo_get(&port->port.xmit_fifo, &c))
 			break;
+
+		outb(c, port->ioaddr + UART_TX);
+		port->icount.tx++;
 	} while (--count > 0);
 
-	if (port->xmit_cnt < WAKEUP_CHARS)
+	if (kfifo_len(&port->port.xmit_fifo) < WAKEUP_CHARS)
 		tty_wakeup(tty);
 
-	if (!port->xmit_cnt)
+	if (kfifo_is_empty(&port->port.xmit_fifo))
 		__mxser_stop_tx(port);
 }
 
-- 
2.34.1

[PATCH 08/11] serial: fsl_linflexuart: deduplicate character sending

[Jiri Slaby]

Introduce a new linflex_put_char() helper to send a character. And use
it on both places this code was duplicated.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Stefan-gabriel Mirea <stefan-gabriel.mirea@nxp.com>
---
 drivers/tty/serial/fsl_linflexuart.c | 42 +++++++++++-----------------
 1 file changed, 17 insertions(+), 25 deletions(-)

diff --git a/drivers/tty/serial/fsl_linflexuart.c b/drivers/tty/serial/fsl_linflexuart.c
index 283757264608..81a04039b6c1 100644
--- a/drivers/tty/serial/fsl_linflexuart.c
+++ b/drivers/tty/serial/fsl_linflexuart.c
@@ -157,27 +157,29 @@ static void linflex_stop_rx(struct uart_port *port)
 	writel(ier & ~LINFLEXD_LINIER_DRIE, port->membase + LINIER);
 }
 
-static inline void linflex_transmit_buffer(struct uart_port *sport)
+static void linflex_put_char(struct uart_port *sport, unsigned char c)
 {
-	struct circ_buf *xmit = &sport->state->xmit;
-	unsigned char c;
 	unsigned long status;
 
-	while (!uart_circ_empty(xmit)) {
-		c = xmit->buf[xmit->tail];
-		writeb(c, sport->membase + BDRL);
+	writeb(c, sport->membase + BDRL);
 
-		/* Waiting for data transmission completed. */
-		while (((status = readl(sport->membase + UARTSR)) &
-					LINFLEXD_UARTSR_DTFTFF) !=
-					LINFLEXD_UARTSR_DTFTFF)
-			;
+	/* Waiting for data transmission completed. */
+	while (((status = readl(sport->membase + UARTSR)) &
+				LINFLEXD_UARTSR_DTFTFF) !=
+				LINFLEXD_UARTSR_DTFTFF)
+		;
+
+	writel(status | LINFLEXD_UARTSR_DTFTFF, sport->membase + UARTSR);
+}
 
+static inline void linflex_transmit_buffer(struct uart_port *sport)
+{
+	struct circ_buf *xmit = &sport->state->xmit;
+
+	while (!uart_circ_empty(xmit)) {
+		linflex_put_char(sport, xmit->buf[xmit->tail]);
 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 		sport->icount.tx++;
-
-		writel(status | LINFLEXD_UARTSR_DTFTFF,
-		       sport->membase + UARTSR);
 	}
 
 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
@@ -201,21 +203,11 @@ static irqreturn_t linflex_txint(int irq, void *dev_id)
 	struct uart_port *sport = dev_id;
 	struct circ_buf *xmit = &sport->state->xmit;
 	unsigned long flags;
-	unsigned long status;
 
 	spin_lock_irqsave(&sport->lock, flags);
 
 	if (sport->x_char) {
-		writeb(sport->x_char, sport->membase + BDRL);
-
-		/* waiting for data transmission completed */
-		while (((status = readl(sport->membase + UARTSR)) &
-			LINFLEXD_UARTSR_DTFTFF) != LINFLEXD_UARTSR_DTFTFF)
-			;
-
-		writel(status | LINFLEXD_UARTSR_DTFTFF,
-		       sport->membase + UARTSR);
-
+		linflex_put_char(sport, sport->x_char);
 		goto out;
 	}
 
-- 
2.34.1

[PATCH 09/11] serial: fsl_linflexuart: don't call uart_write_wakeup() twice

[Jiri Slaby]

linflex_txint() calls linflex_transmit_buffer() which calls
uart_write_wakeup(). So there is no point to repeat it in
linflex_txint() again -- remove it.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Stefan-gabriel Mirea <stefan-gabriel.mirea@nxp.com>
---
 drivers/tty/serial/fsl_linflexuart.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/drivers/tty/serial/fsl_linflexuart.c b/drivers/tty/serial/fsl_linflexuart.c
index 81a04039b6c1..e72cba085743 100644
--- a/drivers/tty/serial/fsl_linflexuart.c
+++ b/drivers/tty/serial/fsl_linflexuart.c
@@ -217,10 +217,6 @@ static irqreturn_t linflex_txint(int irq, void *dev_id)
 	}
 
 	linflex_transmit_buffer(sport);
-
-	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
-		uart_write_wakeup(sport);
-
 out:
 	spin_unlock_irqrestore(&sport->lock, flags);
 	return IRQ_HANDLED;
-- 
2.34.1

[PATCH 10/11] serial: make uart_console_write->putchar()'s character a char

[Jiri Slaby]

Currently, uart_console_write->putchar's second parameter (the
character) is of type int. It makes little sense, provided uart_console_write()
accepts the input string as "const char *s" and passes its content -- the
characters -- to putchar(). So switch the character's type also to char.

This makes the types consistent.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Paul Cercueil <paul@crapouillou.net>
Cc: Tobias Klauser <tklauser@distanz.ch>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Richard Genoud <richard.genoud@gmail.com>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Alexander Shiyan <shc_work@mail.ru>
Cc: Baruch Siach <baruch@tkos.co.il>
Cc: "Maciej W. Rozycki" <macro@orcam.me.uk>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: NXP Linux Team <linux-imx@nxp.com>
Cc: Karol Gugala <kgugala@antmicro.com>
Cc: Mateusz Holenko <mholenko@antmicro.com>
Cc: Vladimir Zapolskiy <vz@mleia.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Jerome Brunet <jbrunet@baylibre.com>
Cc: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: Taichi Sugaya <sugaya.taichi@socionext.com>
Cc: Takao Orito <orito.takao@socionext.com>
Cc: Liviu Dudau <liviu.dudau@arm.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: "Andreas Färber" <afaerber@suse.de>
Cc: Manivannan Sadhasivam <mani@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Andy Gross <agross@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Cc: Orson Zhai <orsonzhai@gmail.com>
Cc: Baolin Wang <baolin.wang7@gmail.com>
Cc: Chunyan Zhang <zhang.lyra@gmail.com>
Cc: Patrice Chotard <patrice.chotard@foss.st.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@foss.st.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Peter Korsgaard <jacmet@sunsite.dk>
Cc: Michal Simek <michal.simek@xilinx.com>
---
 drivers/tty/goldfish.c                     | 2 +-
 drivers/tty/hvc/hvc_dcc.c                  | 2 +-
 drivers/tty/serial/21285.c                 | 2 +-
 drivers/tty/serial/8250/8250_early.c       | 2 +-
 drivers/tty/serial/8250/8250_ingenic.c     | 2 +-
 drivers/tty/serial/8250/8250_port.c        | 2 +-
 drivers/tty/serial/altera_jtaguart.c       | 4 ++--
 drivers/tty/serial/altera_uart.c           | 2 +-
 drivers/tty/serial/amba-pl010.c            | 2 +-
 drivers/tty/serial/amba-pl011.c            | 6 +++---
 drivers/tty/serial/apbuart.c               | 2 +-
 drivers/tty/serial/ar933x_uart.c           | 2 +-
 drivers/tty/serial/arc_uart.c              | 2 +-
 drivers/tty/serial/atmel_serial.c          | 2 +-
 drivers/tty/serial/bcm63xx_uart.c          | 2 +-
 drivers/tty/serial/clps711x.c              | 2 +-
 drivers/tty/serial/digicolor-usart.c       | 2 +-
 drivers/tty/serial/dz.c                    | 2 +-
 drivers/tty/serial/earlycon-arm-semihost.c | 2 +-
 drivers/tty/serial/earlycon-riscv-sbi.c    | 2 +-
 drivers/tty/serial/fsl_linflexuart.c       | 4 ++--
 drivers/tty/serial/fsl_lpuart.c            | 4 ++--
 drivers/tty/serial/imx.c                   | 2 +-
 drivers/tty/serial/imx_earlycon.c          | 2 +-
 drivers/tty/serial/ip22zilog.c             | 2 +-
 drivers/tty/serial/lantiq.c                | 2 +-
 drivers/tty/serial/liteuart.c              | 2 +-
 drivers/tty/serial/lpc32xx_hs.c            | 2 +-
 drivers/tty/serial/meson_uart.c            | 2 +-
 drivers/tty/serial/milbeaut_usio.c         | 2 +-
 drivers/tty/serial/mps2-uart.c             | 4 ++--
 drivers/tty/serial/mvebu-uart.c            | 4 ++--
 drivers/tty/serial/mxs-auart.c             | 2 +-
 drivers/tty/serial/omap-serial.c           | 2 +-
 drivers/tty/serial/owl-uart.c              | 2 +-
 drivers/tty/serial/pch_uart.c              | 2 +-
 drivers/tty/serial/pic32_uart.c            | 2 +-
 drivers/tty/serial/pmac_zilog.c            | 2 +-
 drivers/tty/serial/pxa.c                   | 2 +-
 drivers/tty/serial/qcom_geni_serial.c      | 2 +-
 drivers/tty/serial/rda-uart.c              | 2 +-
 drivers/tty/serial/sa1100.c                | 2 +-
 drivers/tty/serial/samsung_tty.c           | 4 ++--
 drivers/tty/serial/sb1250-duart.c          | 2 +-
 drivers/tty/serial/sccnxp.c                | 2 +-
 drivers/tty/serial/serial_core.c           | 2 +-
 drivers/tty/serial/serial_txx9.c           | 2 +-
 drivers/tty/serial/sh-sci.c                | 2 +-
 drivers/tty/serial/sifive.c                | 4 ++--
 drivers/tty/serial/sprd_serial.c           | 2 +-
 drivers/tty/serial/st-asc.c                | 2 +-
 drivers/tty/serial/stm32-usart.c           | 2 +-
 drivers/tty/serial/sunsu.c                 | 2 +-
 drivers/tty/serial/sunzilog.c              | 4 ++--
 drivers/tty/serial/uartlite.c              | 4 ++--
 drivers/tty/serial/vr41xx_siu.c            | 2 +-
 drivers/tty/serial/vt8500_serial.c         | 2 +-
 drivers/tty/serial/xilinx_uartps.c         | 2 +-
 drivers/tty/serial/zs.c                    | 2 +-
 include/linux/serial_core.h                | 2 +-
 60 files changed, 71 insertions(+), 71 deletions(-)

diff --git a/drivers/tty/goldfish.c b/drivers/tty/goldfish.c
index 5ed19a9857ad..bf51559c0ad3 100644
--- a/drivers/tty/goldfish.c
+++ b/drivers/tty/goldfish.c
@@ -434,7 +434,7 @@ static int goldfish_tty_remove(struct platform_device *pdev)
 }
 
 #ifdef CONFIG_GOLDFISH_TTY_EARLY_CONSOLE
-static void gf_early_console_putchar(struct uart_port *port, int ch)
+static void gf_early_console_putchar(struct uart_port *port, char ch)
 {
 	__raw_writel(ch, port->membase);
 }
diff --git a/drivers/tty/hvc/hvc_dcc.c b/drivers/tty/hvc/hvc_dcc.c
index 8e0edb7d93fd..5fa5e3144011 100644
--- a/drivers/tty/hvc/hvc_dcc.c
+++ b/drivers/tty/hvc/hvc_dcc.c
@@ -15,7 +15,7 @@
 #define DCC_STATUS_RX		(1 << 30)
 #define DCC_STATUS_TX		(1 << 29)
 
-static void dcc_uart_console_putchar(struct uart_port *port, int ch)
+static void dcc_uart_console_putchar(struct uart_port *port, char ch)
 {
 	while (__dcc_getstatus() & DCC_STATUS_TX)
 		cpu_relax();
diff --git a/drivers/tty/serial/21285.c b/drivers/tty/serial/21285.c
index 09baef4ccc39..2d32b151191f 100644
--- a/drivers/tty/serial/21285.c
+++ b/drivers/tty/serial/21285.c
@@ -403,7 +403,7 @@ static void serial21285_setup_ports(void)
 }
 
 #ifdef CONFIG_SERIAL_21285_CONSOLE
-static void serial21285_console_putchar(struct uart_port *port, int ch)
+static void serial21285_console_putchar(struct uart_port *port, char ch)
 {
 	while (*CSR_UARTFLG & 0x20)
 		barrier();
diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
index c171ce6db691..4dedab072922 100644
--- a/drivers/tty/serial/8250/8250_early.c
+++ b/drivers/tty/serial/8250/8250_early.c
@@ -86,7 +86,7 @@ static void serial8250_early_out(struct uart_port *port, int offset, int value)
 
 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
 
-static void serial_putc(struct uart_port *port, int c)
+static void serial_putc(struct uart_port *port, char c)
 {
 	unsigned int status;
 
diff --git a/drivers/tty/serial/8250/8250_ingenic.c b/drivers/tty/serial/8250/8250_ingenic.c
index 65402d05eff9..269c544113d3 100644
--- a/drivers/tty/serial/8250/8250_ingenic.c
+++ b/drivers/tty/serial/8250/8250_ingenic.c
@@ -52,7 +52,7 @@ static void early_out(struct uart_port *port, int offset, uint8_t value)
 	writel(value, port->membase + (offset << 2));
 }
 
-static void ingenic_early_console_putc(struct uart_port *port, int c)
+static void ingenic_early_console_putc(struct uart_port *port, char c)
 {
 	uint8_t lsr;
 
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 2abb3de11a48..5becb36f40fc 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -3303,7 +3303,7 @@ EXPORT_SYMBOL_GPL(serial8250_set_defaults);
 
 #ifdef CONFIG_SERIAL_8250_CONSOLE
 
-static void serial8250_console_putchar(struct uart_port *port, int ch)
+static void serial8250_console_putchar(struct uart_port *port, char ch)
 {
 	struct uart_8250_port *up = up_to_u8250p(port);
 
diff --git a/drivers/tty/serial/altera_jtaguart.c b/drivers/tty/serial/altera_jtaguart.c
index 37bffe406b18..9b22ce8b69f5 100644
--- a/drivers/tty/serial/altera_jtaguart.c
+++ b/drivers/tty/serial/altera_jtaguart.c
@@ -298,7 +298,7 @@ static struct altera_jtaguart altera_jtaguart_ports[ALTERA_JTAGUART_MAXPORTS];
 #if defined(CONFIG_SERIAL_ALTERA_JTAGUART_CONSOLE)
 
 #if defined(CONFIG_SERIAL_ALTERA_JTAGUART_CONSOLE_BYPASS)
-static void altera_jtaguart_console_putc(struct uart_port *port, int c)
+static void altera_jtaguart_console_putc(struct uart_port *port, char c)
 {
 	unsigned long status;
 	unsigned long flags;
@@ -318,7 +318,7 @@ static void altera_jtaguart_console_putc(struct uart_port *port, int c)
 	spin_unlock_irqrestore(&port->lock, flags);
 }
 #else
-static void altera_jtaguart_console_putc(struct uart_port *port, int c)
+static void altera_jtaguart_console_putc(struct uart_port *port, char c)
 {
 	unsigned long flags;
 
diff --git a/drivers/tty/serial/altera_uart.c b/drivers/tty/serial/altera_uart.c
index 64a352b40197..243c30a7c700 100644
--- a/drivers/tty/serial/altera_uart.c
+++ b/drivers/tty/serial/altera_uart.c
@@ -438,7 +438,7 @@ static struct altera_uart altera_uart_ports[CONFIG_SERIAL_ALTERA_UART_MAXPORTS];
 
 #if defined(CONFIG_SERIAL_ALTERA_UART_CONSOLE)
 
-static void altera_uart_console_putc(struct uart_port *port, int c)
+static void altera_uart_console_putc(struct uart_port *port, char c)
 {
 	while (!(altera_uart_readl(port, ALTERA_UART_STATUS_REG) &
 		 ALTERA_UART_STATUS_TRDY_MSK))
diff --git a/drivers/tty/serial/amba-pl010.c b/drivers/tty/serial/amba-pl010.c
index 47654073123d..5f6e50348cdd 100644
--- a/drivers/tty/serial/amba-pl010.c
+++ b/drivers/tty/serial/amba-pl010.c
@@ -556,7 +556,7 @@ static struct uart_amba_port *amba_ports[UART_NR];
 
 #ifdef CONFIG_SERIAL_AMBA_PL010_CONSOLE
 
-static void pl010_console_putchar(struct uart_port *port, int ch)
+static void pl010_console_putchar(struct uart_port *port, char ch)
 {
 	struct uart_amba_port *uap =
 		container_of(port, struct uart_amba_port, port);
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 1f1df46242f9..ff94edbcd791 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -2264,7 +2264,7 @@ static struct uart_amba_port *amba_ports[UART_NR];
 
 #ifdef CONFIG_SERIAL_AMBA_PL011_CONSOLE
 
-static void pl011_console_putchar(struct uart_port *port, int ch)
+static void pl011_console_putchar(struct uart_port *port, char ch)
 {
 	struct uart_amba_port *uap =
 	    container_of(port, struct uart_amba_port, port);
@@ -2480,7 +2480,7 @@ static struct console amba_console = {
 
 #define AMBA_CONSOLE	(&amba_console)
 
-static void qdf2400_e44_putc(struct uart_port *port, int c)
+static void qdf2400_e44_putc(struct uart_port *port, char c)
 {
 	while (readl(port->membase + UART01x_FR) & UART01x_FR_TXFF)
 		cpu_relax();
@@ -2496,7 +2496,7 @@ static void qdf2400_e44_early_write(struct console *con, const char *s, unsigned
 	uart_console_write(&dev->port, s, n, qdf2400_e44_putc);
 }
 
-static void pl011_putc(struct uart_port *port, int c)
+static void pl011_putc(struct uart_port *port, char c)
 {
 	while (readl(port->membase + UART01x_FR) & UART01x_FR_TXFF)
 		cpu_relax();
diff --git a/drivers/tty/serial/apbuart.c b/drivers/tty/serial/apbuart.c
index d8c937bdf3f9..1dd08c1a7685 100644
--- a/drivers/tty/serial/apbuart.c
+++ b/drivers/tty/serial/apbuart.c
@@ -413,7 +413,7 @@ static void apbuart_flush_fifo(struct uart_port *port)
 
 #ifdef CONFIG_SERIAL_GRLIB_GAISLER_APBUART_CONSOLE
 
-static void apbuart_console_putchar(struct uart_port *port, int ch)
+static void apbuart_console_putchar(struct uart_port *port, char ch)
 {
 	unsigned int status;
 	do {
diff --git a/drivers/tty/serial/ar933x_uart.c b/drivers/tty/serial/ar933x_uart.c
index 8cabe50c4a33..92dea51ff2ec 100644
--- a/drivers/tty/serial/ar933x_uart.c
+++ b/drivers/tty/serial/ar933x_uart.c
@@ -613,7 +613,7 @@ static void ar933x_uart_wait_xmitr(struct ar933x_uart_port *up)
 	} while ((status & AR933X_UART_DATA_TX_CSR) == 0);
 }
 
-static void ar933x_uart_console_putchar(struct uart_port *port, int ch)
+static void ar933x_uart_console_putchar(struct uart_port *port, char ch)
 {
 	struct ar933x_uart_port *up =
 		container_of(port, struct ar933x_uart_port, port);
diff --git a/drivers/tty/serial/arc_uart.c b/drivers/tty/serial/arc_uart.c
index 596217d10d5c..e07950ed00b0 100644
--- a/drivers/tty/serial/arc_uart.c
+++ b/drivers/tty/serial/arc_uart.c
@@ -508,7 +508,7 @@ static int arc_serial_console_setup(struct console *co, char *options)
 	return uart_set_options(port, co, baud, parity, bits, flow);
 }
 
-static void arc_serial_console_putchar(struct uart_port *port, int ch)
+static void arc_serial_console_putchar(struct uart_port *port, char ch)
 {
 	while (!(UART_GET_STATUS(port) & TXEMPTY))
 		cpu_relax();
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 2d09a89974a2..e86513227894 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -2541,7 +2541,7 @@ static int atmel_init_port(struct atmel_uart_port *atmel_port,
 }
 
 #ifdef CONFIG_SERIAL_ATMEL_CONSOLE
-static void atmel_console_putchar(struct uart_port *port, int ch)
+static void atmel_console_putchar(struct uart_port *port, char ch)
 {
 	while (!(atmel_uart_readl(port, ATMEL_US_CSR) & ATMEL_US_TXRDY))
 		cpu_relax();
diff --git a/drivers/tty/serial/bcm63xx_uart.c b/drivers/tty/serial/bcm63xx_uart.c
index 6471a54b616b..50943281b599 100644
--- a/drivers/tty/serial/bcm63xx_uart.c
+++ b/drivers/tty/serial/bcm63xx_uart.c
@@ -681,7 +681,7 @@ static void wait_for_xmitr(struct uart_port *port)
 /*
  * output given char
  */
-static void bcm_console_putchar(struct uart_port *port, int ch)
+static void bcm_console_putchar(struct uart_port *port, char ch)
 {
 	wait_for_xmitr(port);
 	bcm_uart_writel(port, ch, UART_FIFO_REG);
diff --git a/drivers/tty/serial/clps711x.c b/drivers/tty/serial/clps711x.c
index 95abc6faa3d5..36bc82ef7951 100644
--- a/drivers/tty/serial/clps711x.c
+++ b/drivers/tty/serial/clps711x.c
@@ -348,7 +348,7 @@ static const struct uart_ops uart_clps711x_ops = {
 };
 
 #ifdef CONFIG_SERIAL_CLPS711X_CONSOLE
-static void uart_clps711x_console_putchar(struct uart_port *port, int ch)
+static void uart_clps711x_console_putchar(struct uart_port *port, char ch)
 {
 	struct clps711x_port *s = dev_get_drvdata(port->dev);
 	u32 sysflg = 0;
diff --git a/drivers/tty/serial/digicolor-usart.c b/drivers/tty/serial/digicolor-usart.c
index 13ac36e2da4f..0641b1c6d1c3 100644
--- a/drivers/tty/serial/digicolor-usart.c
+++ b/drivers/tty/serial/digicolor-usart.c
@@ -381,7 +381,7 @@ static const struct uart_ops digicolor_uart_ops = {
 	.request_port	= digicolor_uart_request_port,
 };
 
-static void digicolor_uart_console_putchar(struct uart_port *port, int ch)
+static void digicolor_uart_console_putchar(struct uart_port *port, char ch)
 {
 	while (digicolor_uart_tx_full(port))
 		cpu_relax();
diff --git a/drivers/tty/serial/dz.c b/drivers/tty/serial/dz.c
index e9edabc5a211..3493e201d67f 100644
--- a/drivers/tty/serial/dz.c
+++ b/drivers/tty/serial/dz.c
@@ -802,7 +802,7 @@ static void __init dz_init_ports(void)
  * restored.  Welcome to the world of PDP-11!
  * -------------------------------------------------------------------
  */
-static void dz_console_putchar(struct uart_port *uport, int ch)
+static void dz_console_putchar(struct uart_port *uport, char ch)
 {
 	struct dz_port *dport = to_dport(uport);
 	unsigned long flags;
diff --git a/drivers/tty/serial/earlycon-arm-semihost.c b/drivers/tty/serial/earlycon-arm-semihost.c
index fa096c10b591..01d63aace0d9 100644
--- a/drivers/tty/serial/earlycon-arm-semihost.c
+++ b/drivers/tty/serial/earlycon-arm-semihost.c
@@ -21,7 +21,7 @@
 /*
  * Semihosting-based debug console
  */
-static void smh_putc(struct uart_port *port, int c)
+static void smh_putc(struct uart_port *port, char c)
 {
 #ifdef CONFIG_ARM64
 	asm volatile("mov  x1, %0\n"
diff --git a/drivers/tty/serial/earlycon-riscv-sbi.c b/drivers/tty/serial/earlycon-riscv-sbi.c
index ce81523c3113..95dbd1a9a48e 100644
--- a/drivers/tty/serial/earlycon-riscv-sbi.c
+++ b/drivers/tty/serial/earlycon-riscv-sbi.c
@@ -10,7 +10,7 @@
 #include <linux/serial_core.h>
 #include <asm/sbi.h>
 
-static void sbi_putc(struct uart_port *port, int c)
+static void sbi_putc(struct uart_port *port, char c)
 {
 	sbi_console_putchar(c);
 }
diff --git a/drivers/tty/serial/fsl_linflexuart.c b/drivers/tty/serial/fsl_linflexuart.c
index e72cba085743..cac2b33d2a66 100644
--- a/drivers/tty/serial/fsl_linflexuart.c
+++ b/drivers/tty/serial/fsl_linflexuart.c
@@ -553,7 +553,7 @@ static const struct uart_ops linflex_pops = {
 static struct uart_port *linflex_ports[UART_NR];
 
 #ifdef CONFIG_SERIAL_FSL_LINFLEXUART_CONSOLE
-static void linflex_console_putchar(struct uart_port *port, int ch)
+static void linflex_console_putchar(struct uart_port *port, char ch)
 {
 	unsigned long cr;
 
@@ -578,7 +578,7 @@ static void linflex_console_putchar(struct uart_port *port, int ch)
 	}
 }
 
-static void linflex_earlycon_putchar(struct uart_port *port, int ch)
+static void linflex_earlycon_putchar(struct uart_port *port, char ch)
 {
 	unsigned long flags;
 	char *ret;
diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index ce3e26144689..b65f9bea67d4 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -2327,13 +2327,13 @@ static const struct uart_ops lpuart32_pops = {
 static struct lpuart_port *lpuart_ports[UART_NR];
 
 #ifdef CONFIG_SERIAL_FSL_LPUART_CONSOLE
-static void lpuart_console_putchar(struct uart_port *port, int ch)
+static void lpuart_console_putchar(struct uart_port *port, char ch)
 {
 	lpuart_wait_bit_set(port, UARTSR1, UARTSR1_TDRE);
 	writeb(ch, port->membase + UARTDR);
 }
 
-static void lpuart32_console_putchar(struct uart_port *port, int ch)
+static void lpuart32_console_putchar(struct uart_port *port, char ch)
 {
 	lpuart32_wait_bit_set(port, UARTSTAT, UARTSTAT_TDRE);
 	lpuart32_write(port, ch, UARTDATA);
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index df8a0c8b8b29..8a5e99c54e5c 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -1958,7 +1958,7 @@ static const struct uart_ops imx_uart_pops = {
 static struct imx_port *imx_uart_ports[UART_NR];
 
 #if IS_ENABLED(CONFIG_SERIAL_IMX_CONSOLE)
-static void imx_uart_console_putchar(struct uart_port *port, int ch)
+static void imx_uart_console_putchar(struct uart_port *port, char ch)
 {
 	struct imx_port *sport = (struct imx_port *)port;
 
diff --git a/drivers/tty/serial/imx_earlycon.c b/drivers/tty/serial/imx_earlycon.c
index 795606e1a22f..0da84092a063 100644
--- a/drivers/tty/serial/imx_earlycon.c
+++ b/drivers/tty/serial/imx_earlycon.c
@@ -16,7 +16,7 @@
 #define UTS_TXFULL (1<<4) /* TxFIFO full */
 #define IMX21_UTS 0xb4 /* UART Test Register on all other i.mx*/
 
-static void imx_uart_console_early_putchar(struct uart_port *port, int ch)
+static void imx_uart_console_early_putchar(struct uart_port *port, char ch)
 {
 	while (readl_relaxed(port->membase + IMX21_UTS) & UTS_TXFULL)
 		cpu_relax();
diff --git a/drivers/tty/serial/ip22zilog.c b/drivers/tty/serial/ip22zilog.c
index f4dc5fe4ba92..be133ba61774 100644
--- a/drivers/tty/serial/ip22zilog.c
+++ b/drivers/tty/serial/ip22zilog.c
@@ -990,7 +990,7 @@ static struct zilog_layout * __init get_zs(int chip)
 #define ZS_PUT_CHAR_MAX_DELAY	2000	/* 10 ms */
 
 #ifdef CONFIG_SERIAL_IP22_ZILOG_CONSOLE
-static void ip22zilog_put_char(struct uart_port *port, int ch)
+static void ip22zilog_put_char(struct uart_port *port, char ch)
 {
 	struct zilog_channel *channel = ZILOG_CHANNEL_FROM_PORT(port);
 	int loops = ZS_PUT_CHAR_MAX_DELAY;
diff --git a/drivers/tty/serial/lantiq.c b/drivers/tty/serial/lantiq.c
index 3e324d3f0a6d..a33b73c49813 100644
--- a/drivers/tty/serial/lantiq.c
+++ b/drivers/tty/serial/lantiq.c
@@ -598,7 +598,7 @@ static const struct uart_ops lqasc_pops = {
 
 #ifdef CONFIG_SERIAL_LANTIQ_CONSOLE
 static void
-lqasc_console_putchar(struct uart_port *port, int ch)
+lqasc_console_putchar(struct uart_port *port, char ch)
 {
 	int fifofree;
 
diff --git a/drivers/tty/serial/liteuart.c b/drivers/tty/serial/liteuart.c
index 7f74bf7bdcff..76ae24199c7f 100644
--- a/drivers/tty/serial/liteuart.c
+++ b/drivers/tty/serial/liteuart.c
@@ -93,7 +93,7 @@ static void liteuart_timer(struct timer_list *t)
 	mod_timer(&uart->timer, jiffies + uart_poll_timeout(port));
 }
 
-static void liteuart_putchar(struct uart_port *port, int ch)
+static void liteuart_putchar(struct uart_port *port, char ch)
 {
 	while (litex_read8(port->membase + OFF_TXFULL))
 		cpu_relax();
diff --git a/drivers/tty/serial/lpc32xx_hs.c b/drivers/tty/serial/lpc32xx_hs.c
index 07c4161eb4cc..1d09e27f727b 100644
--- a/drivers/tty/serial/lpc32xx_hs.c
+++ b/drivers/tty/serial/lpc32xx_hs.c
@@ -122,7 +122,7 @@ static void wait_for_xmit_ready(struct uart_port *port)
 	}
 }
 
-static void lpc32xx_hsuart_console_putchar(struct uart_port *port, int ch)
+static void lpc32xx_hsuart_console_putchar(struct uart_port *port, char ch)
 {
 	wait_for_xmit_ready(port);
 	writel((u32)ch, LPC32XX_HSUART_FIFO(port->membase));
diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
index 45e00d928253..ca0aab7bf1d0 100644
--- a/drivers/tty/serial/meson_uart.c
+++ b/drivers/tty/serial/meson_uart.c
@@ -513,7 +513,7 @@ static void meson_uart_enable_tx_engine(struct uart_port *port)
 	writel(val, port->membase + AML_UART_CONTROL);
 }
 
-static void meson_console_putchar(struct uart_port *port, int ch)
+static void meson_console_putchar(struct uart_port *port, char ch)
 {
 	if (!port->membase)
 		return;
diff --git a/drivers/tty/serial/milbeaut_usio.c b/drivers/tty/serial/milbeaut_usio.c
index 8f2cab7f66ad..60f6529a001a 100644
--- a/drivers/tty/serial/milbeaut_usio.c
+++ b/drivers/tty/serial/milbeaut_usio.c
@@ -400,7 +400,7 @@ static const struct uart_ops mlb_usio_ops = {
 
 #ifdef CONFIG_SERIAL_MILBEAUT_USIO_CONSOLE
 
-static void mlb_usio_console_putchar(struct uart_port *port, int c)
+static void mlb_usio_console_putchar(struct uart_port *port, char c)
 {
 	while (!(readb(port->membase + MLB_USIO_REG_SSR) & MLB_USIO_SSR_TDRE))
 		cpu_relax();
diff --git a/drivers/tty/serial/mps2-uart.c b/drivers/tty/serial/mps2-uart.c
index 587b42f754cb..8af28a73fb25 100644
--- a/drivers/tty/serial/mps2-uart.c
+++ b/drivers/tty/serial/mps2-uart.c
@@ -432,7 +432,7 @@ static const struct uart_ops mps2_uart_pops = {
 static DEFINE_IDR(ports_idr);
 
 #ifdef CONFIG_SERIAL_MPS2_UART_CONSOLE
-static void mps2_uart_console_putchar(struct uart_port *port, int ch)
+static void mps2_uart_console_putchar(struct uart_port *port, char ch)
 {
 	while (mps2_uart_read8(port, UARTn_STATE) & UARTn_STATE_TX_FULL)
 		cpu_relax();
@@ -484,7 +484,7 @@ static struct console mps2_uart_console = {
 
 #define MPS2_SERIAL_CONSOLE (&mps2_uart_console)
 
-static void mps2_early_putchar(struct uart_port *port, int ch)
+static void mps2_early_putchar(struct uart_port *port, char ch)
 {
 	while (readb(port->membase + UARTn_STATE) & UARTn_STATE_TX_FULL)
 		cpu_relax();
diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c
index ab226da75f7b..924af67f73f5 100644
--- a/drivers/tty/serial/mvebu-uart.c
+++ b/drivers/tty/serial/mvebu-uart.c
@@ -598,7 +598,7 @@ static const struct uart_ops mvebu_uart_ops = {
 
 #ifdef CONFIG_SERIAL_MVEBU_CONSOLE
 /* Early Console */
-static void mvebu_uart_putc(struct uart_port *port, int c)
+static void mvebu_uart_putc(struct uart_port *port, char c)
 {
 	unsigned int st;
 
@@ -659,7 +659,7 @@ static void wait_for_xmite(struct uart_port *port)
 				  (val & STAT_TX_EMP), 1, 10000);
 }
 
-static void mvebu_uart_console_putchar(struct uart_port *port, int ch)
+static void mvebu_uart_console_putchar(struct uart_port *port, char ch)
 {
 	wait_for_xmitr(port);
 	writel(ch, port->membase + UART_TSH(port));
diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c
index ac45f3386e97..29ccaa0031c8 100644
--- a/drivers/tty/serial/mxs-auart.c
+++ b/drivers/tty/serial/mxs-auart.c
@@ -1305,7 +1305,7 @@ static const struct uart_ops mxs_auart_ops = {
 static struct mxs_auart_port *auart_port[MXS_AUART_PORTS];
 
 #ifdef CONFIG_SERIAL_MXS_AUART_CONSOLE
-static void mxs_auart_console_putchar(struct uart_port *port, int ch)
+static void mxs_auart_console_putchar(struct uart_port *port, char ch)
 {
 	struct mxs_auart_port *s = to_auart_port(port);
 	unsigned int to = 1000;
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index 0862941862c8..464e9b2a4064 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -1194,7 +1194,7 @@ static void omap_serial_early_out(struct uart_port *port, int offset,
 	writew(value, port->membase + offset);
 }
 
-static void omap_serial_early_putc(struct uart_port *port, int c)
+static void omap_serial_early_putc(struct uart_port *port, char c)
 {
 	unsigned int status;
 
diff --git a/drivers/tty/serial/owl-uart.c b/drivers/tty/serial/owl-uart.c
index 91f1eb0058d7..60eea8e471d8 100644
--- a/drivers/tty/serial/owl-uart.c
+++ b/drivers/tty/serial/owl-uart.c
@@ -516,7 +516,7 @@ static const struct uart_ops owl_uart_ops = {
 
 #ifdef CONFIG_SERIAL_OWL_CONSOLE
 
-static void owl_console_putchar(struct uart_port *port, int ch)
+static void owl_console_putchar(struct uart_port *port, char ch)
 {
 	if (!port->membase)
 		return;
diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c
index f0351e6f0ef6..97b76344288e 100644
--- a/drivers/tty/serial/pch_uart.c
+++ b/drivers/tty/serial/pch_uart.c
@@ -1600,7 +1600,7 @@ static const struct uart_ops pch_uart_ops = {
 
 #ifdef CONFIG_SERIAL_PCH_UART_CONSOLE
 
-static void pch_console_putchar(struct uart_port *port, int ch)
+static void pch_console_putchar(struct uart_port *port, char ch)
 {
 	struct eg20t_port *priv =
 		container_of(port, struct eg20t_port, port);
diff --git a/drivers/tty/serial/pic32_uart.c b/drivers/tty/serial/pic32_uart.c
index 0a12fb11e698..c5dca0a19dbb 100644
--- a/drivers/tty/serial/pic32_uart.c
+++ b/drivers/tty/serial/pic32_uart.c
@@ -691,7 +691,7 @@ static const struct uart_ops pic32_uart_ops = {
 
 #ifdef CONFIG_SERIAL_PIC32_CONSOLE
 /* output given char */
-static void pic32_console_putchar(struct uart_port *port, int ch)
+static void pic32_console_putchar(struct uart_port *port, char ch)
 {
 	struct pic32_sport *sport = to_pic32_sport(port);
 
diff --git a/drivers/tty/serial/pmac_zilog.c b/drivers/tty/serial/pmac_zilog.c
index 5359236b32d6..555f94240098 100644
--- a/drivers/tty/serial/pmac_zilog.c
+++ b/drivers/tty/serial/pmac_zilog.c
@@ -1944,7 +1944,7 @@ static void __exit exit_pmz(void)
 
 #ifdef CONFIG_SERIAL_PMACZILOG_CONSOLE
 
-static void pmz_console_putchar(struct uart_port *port, int ch)
+static void pmz_console_putchar(struct uart_port *port, char ch)
 {
 	struct uart_pmac_port *uap =
 		container_of(port, struct uart_pmac_port, port);
diff --git a/drivers/tty/serial/pxa.c b/drivers/tty/serial/pxa.c
index 30b099746a75..c92502abe6fb 100644
--- a/drivers/tty/serial/pxa.c
+++ b/drivers/tty/serial/pxa.c
@@ -619,7 +619,7 @@ static void wait_for_xmitr(struct uart_pxa_port *up)
 	}
 }
 
-static void serial_pxa_console_putchar(struct uart_port *port, int ch)
+static void serial_pxa_console_putchar(struct uart_port *port, char ch)
 {
 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
 
diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
index aedc38893e6c..38c2877881a4 100644
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -397,7 +397,7 @@ static void qcom_geni_serial_poll_put_char(struct uart_port *uport,
 #endif
 
 #ifdef CONFIG_SERIAL_QCOM_GENI_CONSOLE
-static void qcom_geni_serial_wr_char(struct uart_port *uport, int ch)
+static void qcom_geni_serial_wr_char(struct uart_port *uport, char ch)
 {
 	struct qcom_geni_private_data *private_data = uport->private_data;
 
diff --git a/drivers/tty/serial/rda-uart.c b/drivers/tty/serial/rda-uart.c
index d550d8fa2fab..95af78d8140b 100644
--- a/drivers/tty/serial/rda-uart.c
+++ b/drivers/tty/serial/rda-uart.c
@@ -573,7 +573,7 @@ static const struct uart_ops rda_uart_ops = {
 
 #ifdef CONFIG_SERIAL_RDA_CONSOLE
 
-static void rda_console_putchar(struct uart_port *port, int ch)
+static void rda_console_putchar(struct uart_port *port, char ch)
 {
 	if (!port->membase)
 		return;
diff --git a/drivers/tty/serial/sa1100.c b/drivers/tty/serial/sa1100.c
index 697b6a002a16..bfd37745cc6e 100644
--- a/drivers/tty/serial/sa1100.c
+++ b/drivers/tty/serial/sa1100.c
@@ -695,7 +695,7 @@ void __init sa1100_register_uart(int idx, int port)
 
 
 #ifdef CONFIG_SERIAL_SA1100_CONSOLE
-static void sa1100_console_putchar(struct uart_port *port, int ch)
+static void sa1100_console_putchar(struct uart_port *port, char ch)
 {
 	struct sa1100_port *sport =
 		container_of(port, struct sa1100_port, port);
diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c
index d002a4e48ed9..6fef292d6e9c 100644
--- a/drivers/tty/serial/samsung_tty.c
+++ b/drivers/tty/serial/samsung_tty.c
@@ -2478,7 +2478,7 @@ static void s3c24xx_serial_put_poll_char(struct uart_port *port,
 #endif /* CONFIG_CONSOLE_POLL */
 
 static void
-s3c24xx_serial_console_putchar(struct uart_port *port, int ch)
+s3c24xx_serial_console_putchar(struct uart_port *port, char ch)
 {
 	unsigned int ufcon = rd_regl(port, S3C2410_UFCON);
 
@@ -2965,7 +2965,7 @@ static void samsung_early_busyuart_fifo(struct uart_port *port)
 		;
 }
 
-static void samsung_early_putc(struct uart_port *port, int c)
+static void samsung_early_putc(struct uart_port *port, char c)
 {
 	if (readl(port->membase + S3C2410_UFCON) & S3C2410_UFCON_FIFOMODE)
 		samsung_early_busyuart_fifo(port);
diff --git a/drivers/tty/serial/sb1250-duart.c b/drivers/tty/serial/sb1250-duart.c
index 738df6d9c0d9..bb1913050796 100644
--- a/drivers/tty/serial/sb1250-duart.c
+++ b/drivers/tty/serial/sb1250-duart.c
@@ -820,7 +820,7 @@ static void __init sbd_probe_duarts(void)
  * console output.  The console_lock is held by the caller, so we
  * shouldn't be interrupted for more console activity.
  */
-static void sbd_console_putchar(struct uart_port *uport, int ch)
+static void sbd_console_putchar(struct uart_port *uport, char ch)
 {
 	struct sbd_port *sport = to_sport(uport);
 
diff --git a/drivers/tty/serial/sccnxp.c b/drivers/tty/serial/sccnxp.c
index 10cc16a71f26..3ee2c942ac22 100644
--- a/drivers/tty/serial/sccnxp.c
+++ b/drivers/tty/serial/sccnxp.c
@@ -828,7 +828,7 @@ static const struct uart_ops sccnxp_ops = {
 };
 
 #ifdef CONFIG_SERIAL_SCCNXP_CONSOLE
-static void sccnxp_console_putchar(struct uart_port *port, int c)
+static void sccnxp_console_putchar(struct uart_port *port, char c)
 {
 	int tryes = 100000;
 
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 1f6df577c75b..33742d86a12e 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -1926,7 +1926,7 @@ static void uart_port_spin_lock_init(struct uart_port *port)
  */
 void uart_console_write(struct uart_port *port, const char *s,
 			unsigned int count,
-			void (*putchar)(struct uart_port *, int))
+			void (*putchar)(struct uart_port *, char))
 {
 	unsigned int i;
 
diff --git a/drivers/tty/serial/serial_txx9.c b/drivers/tty/serial/serial_txx9.c
index aaca4fe38486..e1003fd280dd 100644
--- a/drivers/tty/serial/serial_txx9.c
+++ b/drivers/tty/serial/serial_txx9.c
@@ -879,7 +879,7 @@ static void __init serial_txx9_register_ports(struct uart_driver *drv,
 
 #ifdef CONFIG_SERIAL_TXX9_CONSOLE
 
-static void serial_txx9_console_putchar(struct uart_port *port, int ch)
+static void serial_txx9_console_putchar(struct uart_port *port, char ch)
 {
 	struct uart_txx9_port *up = to_uart_txx9_port(port);
 
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index b610b27893a8..67846605713b 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -2957,7 +2957,7 @@ static void sci_cleanup_single(struct sci_port *port)
 
 #if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
     defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
-static void serial_console_putchar(struct uart_port *port, int ch)
+static void serial_console_putchar(struct uart_port *port, char ch)
 {
 	sci_poll_put_char(port, ch);
 }
diff --git a/drivers/tty/serial/sifive.c b/drivers/tty/serial/sifive.c
index b79900d0e91a..9f4923bc3afb 100644
--- a/drivers/tty/serial/sifive.c
+++ b/drivers/tty/serial/sifive.c
@@ -756,7 +756,7 @@ static void sifive_serial_poll_put_char(struct uart_port *port,
  */
 
 #ifdef CONFIG_SERIAL_EARLYCON
-static void early_sifive_serial_putc(struct uart_port *port, int c)
+static void early_sifive_serial_putc(struct uart_port *port, char c)
 {
 	while (__ssp_early_readl(port, SIFIVE_SERIAL_TXDATA_OFFS) &
 	       SIFIVE_SERIAL_TXDATA_FULL_MASK)
@@ -800,7 +800,7 @@ OF_EARLYCON_DECLARE(sifive, "sifive,fu540-c000-uart0",
 
 static struct sifive_serial_port *sifive_serial_console_ports[SIFIVE_SERIAL_MAX_PORTS];
 
-static void sifive_serial_console_putchar(struct uart_port *port, int ch)
+static void sifive_serial_console_putchar(struct uart_port *port, char ch)
 {
 	struct sifive_serial_port *ssp = port_to_sifive_serial_port(port);
 
diff --git a/drivers/tty/serial/sprd_serial.c b/drivers/tty/serial/sprd_serial.c
index 9a7ae6384edf..45cebfed0378 100644
--- a/drivers/tty/serial/sprd_serial.c
+++ b/drivers/tty/serial/sprd_serial.c
@@ -1058,7 +1058,7 @@ console_initcall(sprd_serial_console_init);
 #define SPRD_CONSOLE	(&sprd_console)
 
 /* Support for earlycon */
-static void sprd_putc(struct uart_port *port, int c)
+static void sprd_putc(struct uart_port *port, char c)
 {
 	unsigned int timeout = SPRD_TIMEOUT;
 
diff --git a/drivers/tty/serial/st-asc.c b/drivers/tty/serial/st-asc.c
index 87e480cc8206..6418a7f4fdde 100644
--- a/drivers/tty/serial/st-asc.c
+++ b/drivers/tty/serial/st-asc.c
@@ -854,7 +854,7 @@ static int asc_serial_resume(struct device *dev)
 /*----------------------------------------------------------------------*/
 
 #ifdef CONFIG_SERIAL_ST_ASC_CONSOLE
-static void asc_console_putchar(struct uart_port *port, int ch)
+static void asc_console_putchar(struct uart_port *port, char ch)
 {
 	unsigned int timeout = 1000000;
 
diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c
index 1f89ab0e49ac..7c7aace2418f 100644
--- a/drivers/tty/serial/stm32-usart.c
+++ b/drivers/tty/serial/stm32-usart.c
@@ -1629,7 +1629,7 @@ static int stm32_usart_serial_remove(struct platform_device *pdev)
 }
 
 #ifdef CONFIG_SERIAL_STM32_CONSOLE
-static void stm32_usart_console_putchar(struct uart_port *port, int ch)
+static void stm32_usart_console_putchar(struct uart_port *port, char ch)
 {
 	struct stm32_port *stm32_port = to_stm32_port(port);
 	const struct stm32_usart_offsets *ofs = &stm32_port->info->ofs;
diff --git a/drivers/tty/serial/sunsu.c b/drivers/tty/serial/sunsu.c
index 98b2f4fb9a99..029a98ead88c 100644
--- a/drivers/tty/serial/sunsu.c
+++ b/drivers/tty/serial/sunsu.c
@@ -1281,7 +1281,7 @@ static void wait_for_xmitr(struct uart_sunsu_port *up)
 	}
 }
 
-static void sunsu_console_putchar(struct uart_port *port, int ch)
+static void sunsu_console_putchar(struct uart_port *port, char ch)
 {
 	struct uart_sunsu_port *up =
 		container_of(port, struct uart_sunsu_port, port);
diff --git a/drivers/tty/serial/sunzilog.c b/drivers/tty/serial/sunzilog.c
index b714b00d2dad..d070e42f1c37 100644
--- a/drivers/tty/serial/sunzilog.c
+++ b/drivers/tty/serial/sunzilog.c
@@ -100,7 +100,7 @@ struct uart_sunzilog_port {
 #endif
 };
 
-static void sunzilog_putchar(struct uart_port *port, int ch);
+static void sunzilog_putchar(struct uart_port *port, char ch);
 
 #define ZILOG_CHANNEL_FROM_PORT(PORT)	((struct zilog_channel __iomem *)((PORT)->membase))
 #define UART_ZILOG(PORT)		((struct uart_sunzilog_port *)(PORT))
@@ -1125,7 +1125,7 @@ static void sunzilog_free_tables(void)
 
 #define ZS_PUT_CHAR_MAX_DELAY	2000	/* 10 ms */
 
-static void __maybe_unused sunzilog_putchar(struct uart_port *port, int ch)
+static void __maybe_unused sunzilog_putchar(struct uart_port *port, char ch)
 {
 	struct zilog_channel __iomem *channel = ZILOG_CHANNEL_FROM_PORT(port);
 	int loops = ZS_PUT_CHAR_MAX_DELAY;
diff --git a/drivers/tty/serial/uartlite.c b/drivers/tty/serial/uartlite.c
index e1fa52d31474..f1b342c1e2fb 100644
--- a/drivers/tty/serial/uartlite.c
+++ b/drivers/tty/serial/uartlite.c
@@ -482,7 +482,7 @@ static void ulite_console_wait_tx(struct uart_port *port)
 			 "timeout waiting for TX buffer empty\n");
 }
 
-static void ulite_console_putchar(struct uart_port *port, int ch)
+static void ulite_console_putchar(struct uart_port *port, char ch)
 {
 	ulite_console_wait_tx(port);
 	uart_out32(ch, ULITE_TX, port);
@@ -558,7 +558,7 @@ static struct console ulite_console = {
 	.data	= &ulite_uart_driver,
 };
 
-static void early_uartlite_putc(struct uart_port *port, int c)
+static void early_uartlite_putc(struct uart_port *port, char c)
 {
 	/*
 	 * Limit how many times we'll spin waiting for TX FIFO status.
diff --git a/drivers/tty/serial/vr41xx_siu.c b/drivers/tty/serial/vr41xx_siu.c
index 647198b1e2b9..8029d2d8e6fb 100644
--- a/drivers/tty/serial/vr41xx_siu.c
+++ b/drivers/tty/serial/vr41xx_siu.c
@@ -743,7 +743,7 @@ static void wait_for_xmitr(struct uart_port *port)
 	}
 }
 
-static void siu_console_putchar(struct uart_port *port, int ch)
+static void siu_console_putchar(struct uart_port *port, char ch)
 {
 	wait_for_xmitr(port);
 	siu_write(port, UART_TX, ch);
diff --git a/drivers/tty/serial/vt8500_serial.c b/drivers/tty/serial/vt8500_serial.c
index 9adfe3dc970f..375a6959439d 100644
--- a/drivers/tty/serial/vt8500_serial.c
+++ b/drivers/tty/serial/vt8500_serial.c
@@ -484,7 +484,7 @@ static void wait_for_xmitr(struct uart_port *port)
 	} while (status & 0x10);
 }
 
-static void vt8500_console_putchar(struct uart_port *port, int c)
+static void vt8500_console_putchar(struct uart_port *port, char c)
 {
 	wait_for_xmitr(port);
 	writeb(c, port->membase + VT8500_TXFIFO);
diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index d5e243908d9f..bdcd7dd743ef 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -1142,7 +1142,7 @@ static struct uart_driver cdns_uart_uart_driver;
  * @port: Handle to the uart port structure
  * @ch: Character to be written
  */
-static void cdns_uart_console_putchar(struct uart_port *port, int ch)
+static void cdns_uart_console_putchar(struct uart_port *port, char ch)
 {
 	while (readl(port->membase + CDNS_UART_SR) & CDNS_UART_SR_TXFULL)
 		cpu_relax();
diff --git a/drivers/tty/serial/zs.c b/drivers/tty/serial/zs.c
index 4b4f604646a7..d63aa07653ca 100644
--- a/drivers/tty/serial/zs.c
+++ b/drivers/tty/serial/zs.c
@@ -1124,7 +1124,7 @@ static int __init zs_probe_sccs(void)
 
 
 #ifdef CONFIG_SERIAL_ZS_CONSOLE
-static void zs_console_putchar(struct uart_port *uport, int ch)
+static void zs_console_putchar(struct uart_port *uport, char ch)
 {
 	struct zs_port *zport = to_zport(uport);
 	struct zs_scc *scc = zport->scc;
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index c58cc142d23f..68e62703eaa6 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -399,7 +399,7 @@ int uart_set_options(struct uart_port *port, struct console *co, int baud,
 struct tty_driver *uart_console_device(struct console *co, int *index);
 void uart_console_write(struct uart_port *port, const char *s,
 			unsigned int count,
-			void (*putchar)(struct uart_port *, int));
+			void (*putchar)(struct uart_port *, char));
 
 /*
  * Port/driver registration/removal
-- 
2.34.1

Re: [PATCH 10/11] serial: make uart_console_write->putchar()'s character a char

[Richard Genoud]

Le 24/01/2022 à 08:14, Jiri Slaby a écrit :
> Currently, uart_console_write->putchar's second parameter (the
> character) is of type int. It makes little sense, provided uart_console_write()
> accepts the input string as "const char *s" and passes its content -- the
> characters -- to putchar(). So switch the character's type also to char.
> 
> This makes the types consistent.
> 
> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
> Cc: Paul Cercueil <paul@crapouillou.net>
> Cc: Tobias Klauser <tklauser@distanz.ch>
> Cc: Russell King <linux@armlinux.org.uk>
> Cc: Vineet Gupta <vgupta@kernel.org>
> Cc: Richard Genoud <richard.genoud@gmail.com>
> Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
> Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
> Cc: Florian Fainelli <f.fainelli@gmail.com>
> Cc: Alexander Shiyan <shc_work@mail.ru>
> Cc: Baruch Siach <baruch@tkos.co.il>
> Cc: "Maciej W. Rozycki" <macro@orcam.me.uk>
> Cc: Paul Walmsley <paul.walmsley@sifive.com>
> Cc: Palmer Dabbelt <palmer@dabbelt.com>
> Cc: Albert Ou <aou@eecs.berkeley.edu>
> Cc: Shawn Guo <shawnguo@kernel.org>
> Cc: Sascha Hauer <s.hauer@pengutronix.de>
> Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
> Cc: Fabio Estevam <festevam@gmail.com>
> Cc: NXP Linux Team <linux-imx@nxp.com>
> Cc: Karol Gugala <kgugala@antmicro.com>
> Cc: Mateusz Holenko <mholenko@antmicro.com>
> Cc: Vladimir Zapolskiy <vz@mleia.com>
> Cc: Neil Armstrong <narmstrong@baylibre.com>
> Cc: Kevin Hilman <khilman@baylibre.com>
> Cc: Jerome Brunet <jbrunet@baylibre.com>
> Cc: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
> Cc: Taichi Sugaya <sugaya.taichi@socionext.com>
> Cc: Takao Orito <orito.takao@socionext.com>
> Cc: Liviu Dudau <liviu.dudau@arm.com>
> Cc: Sudeep Holla <sudeep.holla@arm.com>
> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> Cc: "Andreas Färber" <afaerber@suse.de>
> Cc: Manivannan Sadhasivam <mani@kernel.org>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> Cc: Paul Mackerras <paulus@samba.org>
> Cc: Andy Gross <agross@kernel.org>
> Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
> Cc: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
> Cc: Orson Zhai <orsonzhai@gmail.com>
> Cc: Baolin Wang <baolin.wang7@gmail.com>
> Cc: Chunyan Zhang <zhang.lyra@gmail.com>
> Cc: Patrice Chotard <patrice.chotard@foss.st.com>
> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
> Cc: Alexandre Torgue <alexandre.torgue@foss.st.com>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: Peter Korsgaard <jacmet@sunsite.dk>
> Cc: Michal Simek <michal.simek@xilinx.com>
For drivers/tty/serial/atmel_serial.c:
Acked-by: Richard Genoud <richard.genoud@gmail.com>

> ---
>   drivers/tty/goldfish.c                     | 2 +-
>   drivers/tty/hvc/hvc_dcc.c                  | 2 +-
>   drivers/tty/serial/21285.c                 | 2 +-
>   drivers/tty/serial/8250/8250_early.c       | 2 +-
>   drivers/tty/serial/8250/8250_ingenic.c     | 2 +-
>   drivers/tty/serial/8250/8250_port.c        | 2 +-
>   drivers/tty/serial/altera_jtaguart.c       | 4 ++--
>   drivers/tty/serial/altera_uart.c           | 2 +-
>   drivers/tty/serial/amba-pl010.c            | 2 +-
>   drivers/tty/serial/amba-pl011.c            | 6 +++---
>   drivers/tty/serial/apbuart.c               | 2 +-
>   drivers/tty/serial/ar933x_uart.c           | 2 +-
>   drivers/tty/serial/arc_uart.c              | 2 +-
>   drivers/tty/serial/atmel_serial.c          | 2 +-
>   drivers/tty/serial/bcm63xx_uart.c          | 2 +-
>   drivers/tty/serial/clps711x.c              | 2 +-
>   drivers/tty/serial/digicolor-usart.c       | 2 +-
>   drivers/tty/serial/dz.c                    | 2 +-
>   drivers/tty/serial/earlycon-arm-semihost.c | 2 +-
>   drivers/tty/serial/earlycon-riscv-sbi.c    | 2 +-
>   drivers/tty/serial/fsl_linflexuart.c       | 4 ++--
>   drivers/tty/serial/fsl_lpuart.c            | 4 ++--
>   drivers/tty/serial/imx.c                   | 2 +-
>   drivers/tty/serial/imx_earlycon.c          | 2 +-
>   drivers/tty/serial/ip22zilog.c             | 2 +-
>   drivers/tty/serial/lantiq.c                | 2 +-
>   drivers/tty/serial/liteuart.c              | 2 +-
>   drivers/tty/serial/lpc32xx_hs.c            | 2 +-
>   drivers/tty/serial/meson_uart.c            | 2 +-
>   drivers/tty/serial/milbeaut_usio.c         | 2 +-
>   drivers/tty/serial/mps2-uart.c             | 4 ++--
>   drivers/tty/serial/mvebu-uart.c            | 4 ++--
>   drivers/tty/serial/mxs-auart.c             | 2 +-
>   drivers/tty/serial/omap-serial.c           | 2 +-
>   drivers/tty/serial/owl-uart.c              | 2 +-
>   drivers/tty/serial/pch_uart.c              | 2 +-
>   drivers/tty/serial/pic32_uart.c            | 2 +-
>   drivers/tty/serial/pmac_zilog.c            | 2 +-
>   drivers/tty/serial/pxa.c                   | 2 +-
>   drivers/tty/serial/qcom_geni_serial.c      | 2 +-
>   drivers/tty/serial/rda-uart.c              | 2 +-
>   drivers/tty/serial/sa1100.c                | 2 +-
>   drivers/tty/serial/samsung_tty.c           | 4 ++--
>   drivers/tty/serial/sb1250-duart.c          | 2 +-
>   drivers/tty/serial/sccnxp.c                | 2 +-
>   drivers/tty/serial/serial_core.c           | 2 +-
>   drivers/tty/serial/serial_txx9.c           | 2 +-
>   drivers/tty/serial/sh-sci.c                | 2 +-
>   drivers/tty/serial/sifive.c                | 4 ++--
>   drivers/tty/serial/sprd_serial.c           | 2 +-
>   drivers/tty/serial/st-asc.c                | 2 +-
>   drivers/tty/serial/stm32-usart.c           | 2 +-
>   drivers/tty/serial/sunsu.c                 | 2 +-
>   drivers/tty/serial/sunzilog.c              | 4 ++--
>   drivers/tty/serial/uartlite.c              | 4 ++--
>   drivers/tty/serial/vr41xx_siu.c            | 2 +-
>   drivers/tty/serial/vt8500_serial.c         | 2 +-
>   drivers/tty/serial/xilinx_uartps.c         | 2 +-
>   drivers/tty/serial/zs.c                    | 2 +-
>   include/linux/serial_core.h                | 2 +-
>   60 files changed, 71 insertions(+), 71 deletions(-)
> 
Thanks!

Re: [PATCH 10/11] serial: make uart_console_write->putchar()'s character a char

[kernel test robot]

Hi Jiri,

I love your patch! Yet something to improve:

[auto build test ERROR on tty/tty-testing]
[also build test ERROR on v5.17-rc1 next-20220124]
[cannot apply to shawnguo/for-next davem-sparc/master]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Jiri-Slaby/TTY-patches-for-5-18/20220124-151758
base:   https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git tty-testing
config: microblaze-randconfig-r006-20220124 (https://download.01.org/0day-ci/archive/20220124/202201242255.WTSwb6EN-lkp@intel.com/config)
compiler: microblaze-linux-gcc (GCC) 11.2.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/45520d4f6db241db0b77f41162adba4a9977956c
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Jiri-Slaby/TTY-patches-for-5-18/20220124-151758
        git checkout 45520d4f6db241db0b77f41162adba4a9977956c
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=microblaze SHELL=/bin/bash drivers/tty/serial/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   drivers/tty/serial/sprd_serial.c: In function 'sprd_console_write':
>> drivers/tty/serial/sprd_serial.c:1007:44: error: passing argument 4 of 'uart_console_write' from incompatible pointer type [-Werror=incompatible-pointer-types]
    1007 |         uart_console_write(port, s, count, sprd_console_putchar);
         |                                            ^~~~~~~~~~~~~~~~~~~~
         |                                            |
         |                                            void (*)(struct uart_port *, int)
   In file included from drivers/tty/serial/sprd_serial.c:18:
   include/linux/serial_core.h:402:32: note: expected 'void (*)(struct uart_port *, char)' but argument is of type 'void (*)(struct uart_port *, int)'
     402 |                         void (*putchar)(struct uart_port *, char));
         |                         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   cc1: some warnings being treated as errors


vim +/uart_console_write +1007 drivers/tty/serial/sprd_serial.c

b7396a38fb28db Chunyan Zhang 2015-01-28   992  
b7396a38fb28db Chunyan Zhang 2015-01-28   993  static void sprd_console_write(struct console *co, const char *s,
b7396a38fb28db Chunyan Zhang 2015-01-28   994  			       unsigned int count)
b7396a38fb28db Chunyan Zhang 2015-01-28   995  {
b7396a38fb28db Chunyan Zhang 2015-01-28   996  	struct uart_port *port = &sprd_port[co->index]->port;
b7396a38fb28db Chunyan Zhang 2015-01-28   997  	int locked = 1;
b7396a38fb28db Chunyan Zhang 2015-01-28   998  	unsigned long flags;
b7396a38fb28db Chunyan Zhang 2015-01-28   999  
b7396a38fb28db Chunyan Zhang 2015-01-28  1000  	if (port->sysrq)
b7396a38fb28db Chunyan Zhang 2015-01-28  1001  		locked = 0;
b7396a38fb28db Chunyan Zhang 2015-01-28  1002  	else if (oops_in_progress)
b7396a38fb28db Chunyan Zhang 2015-01-28  1003  		locked = spin_trylock_irqsave(&port->lock, flags);
b7396a38fb28db Chunyan Zhang 2015-01-28  1004  	else
b7396a38fb28db Chunyan Zhang 2015-01-28  1005  		spin_lock_irqsave(&port->lock, flags);
b7396a38fb28db Chunyan Zhang 2015-01-28  1006  
b7396a38fb28db Chunyan Zhang 2015-01-28 @1007  	uart_console_write(port, s, count, sprd_console_putchar);
b7396a38fb28db Chunyan Zhang 2015-01-28  1008  
b7396a38fb28db Chunyan Zhang 2015-01-28  1009  	/* wait for transmitter to become empty */
b7396a38fb28db Chunyan Zhang 2015-01-28  1010  	wait_for_xmitr(port);
b7396a38fb28db Chunyan Zhang 2015-01-28  1011  
b7396a38fb28db Chunyan Zhang 2015-01-28  1012  	if (locked)
b7396a38fb28db Chunyan Zhang 2015-01-28  1013  		spin_unlock_irqrestore(&port->lock, flags);
b7396a38fb28db Chunyan Zhang 2015-01-28  1014  }
b7396a38fb28db Chunyan Zhang 2015-01-28  1015  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

Re: [PATCH 10/11] serial: make uart_console_write->putchar()'s character a char

[Jiri Slaby]

On 24. 01. 22, 15:30, kernel test robot wrote:
> Hi Jiri,
> 
> I love your patch! Yet something to improve:

Please skip this patch. I wonder why the bot didn't catch it in my queue 
already.

> [auto build test ERROR on tty/tty-testing]
> [also build test ERROR on v5.17-rc1 next-20220124]
> [cannot apply to shawnguo/for-next davem-sparc/master]
> [If your patch is applied to the wrong git tree, kindly drop us a note.
> And when submitting patch, we suggest to use '--base' as documented in
> https://git-scm.com/docs/git-format-patch]
> 
> url:    https://github.com/0day-ci/linux/commits/Jiri-Slaby/TTY-patches-for-5-18/20220124-151758
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git tty-testing
> config: microblaze-randconfig-r006-20220124 (https://download.01.org/0day-ci/archive/20220124/202201242255.WTSwb6EN-lkp@intel.com/config)
> compiler: microblaze-linux-gcc (GCC) 11.2.0
> reproduce (this is a W=1 build):
>          wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>          chmod +x ~/bin/make.cross
>          # https://github.com/0day-ci/linux/commit/45520d4f6db241db0b77f41162adba4a9977956c
>          git remote add linux-review https://github.com/0day-ci/linux
>          git fetch --no-tags linux-review Jiri-Slaby/TTY-patches-for-5-18/20220124-151758
>          git checkout 45520d4f6db241db0b77f41162adba4a9977956c
>          # save the config file to linux build tree
>          mkdir build_dir
>          COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=microblaze SHELL=/bin/bash drivers/tty/serial/
> 
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@intel.com>
> 
> All errors (new ones prefixed by >>):
> 
>     drivers/tty/serial/sprd_serial.c: In function 'sprd_console_write':
>>> drivers/tty/serial/sprd_serial.c:1007:44: error: passing argument 4 of 'uart_console_write' from incompatible pointer type [-Werror=incompatible-pointer-types]
>      1007 |         uart_console_write(port, s, count, sprd_console_putchar);
>           |                                            ^~~~~~~~~~~~~~~~~~~~
>           |                                            |
>           |                                            void (*)(struct uart_port *, int)
>     In file included from drivers/tty/serial/sprd_serial.c:18:
>     include/linux/serial_core.h:402:32: note: expected 'void (*)(struct uart_port *, char)' but argument is of type 'void (*)(struct uart_port *, int)'
>       402 |                         void (*putchar)(struct uart_port *, char));
>           |                         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>     cc1: some warnings being treated as errors
> 
> 
> vim +/uart_console_write +1007 drivers/tty/serial/sprd_serial.c
> 
> b7396a38fb28db Chunyan Zhang 2015-01-28   992
> b7396a38fb28db Chunyan Zhang 2015-01-28   993  static void sprd_console_write(struct console *co, const char *s,
> b7396a38fb28db Chunyan Zhang 2015-01-28   994  			       unsigned int count)
> b7396a38fb28db Chunyan Zhang 2015-01-28   995  {
> b7396a38fb28db Chunyan Zhang 2015-01-28   996  	struct uart_port *port = &sprd_port[co->index]->port;
> b7396a38fb28db Chunyan Zhang 2015-01-28   997  	int locked = 1;
> b7396a38fb28db Chunyan Zhang 2015-01-28   998  	unsigned long flags;
> b7396a38fb28db Chunyan Zhang 2015-01-28   999
> b7396a38fb28db Chunyan Zhang 2015-01-28  1000  	if (port->sysrq)
> b7396a38fb28db Chunyan Zhang 2015-01-28  1001  		locked = 0;
> b7396a38fb28db Chunyan Zhang 2015-01-28  1002  	else if (oops_in_progress)
> b7396a38fb28db Chunyan Zhang 2015-01-28  1003  		locked = spin_trylock_irqsave(&port->lock, flags);
> b7396a38fb28db Chunyan Zhang 2015-01-28  1004  	else
> b7396a38fb28db Chunyan Zhang 2015-01-28  1005  		spin_lock_irqsave(&port->lock, flags);
> b7396a38fb28db Chunyan Zhang 2015-01-28  1006
> b7396a38fb28db Chunyan Zhang 2015-01-28 @1007  	uart_console_write(port, s, count, sprd_console_putchar);
> b7396a38fb28db Chunyan Zhang 2015-01-28  1008
> b7396a38fb28db Chunyan Zhang 2015-01-28  1009  	/* wait for transmitter to become empty */
> b7396a38fb28db Chunyan Zhang 2015-01-28  1010  	wait_for_xmitr(port);
> b7396a38fb28db Chunyan Zhang 2015-01-28  1011
> b7396a38fb28db Chunyan Zhang 2015-01-28  1012  	if (locked)
> b7396a38fb28db Chunyan Zhang 2015-01-28  1013  		spin_unlock_irqrestore(&port->lock, flags);
> b7396a38fb28db Chunyan Zhang 2015-01-28  1014  }
> b7396a38fb28db Chunyan Zhang 2015-01-28  1015
> 
> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org


-- 
js
suse labs

Re: [PATCH 10/11] serial: make uart_console_write->putchar()'s character a char

[Greg KH]

On Wed, Jan 26, 2022 at 08:26:48AM +0100, Jiri Slaby wrote:
> On 24. 01. 22, 15:30, kernel test robot wrote:
> > Hi Jiri,
> > 
> > I love your patch! Yet something to improve:
> 
> Please skip this patch. I wonder why the bot didn't catch it in my queue
> already.

Now skipped.  Thanks for all of the other patches, now queued up.

greg k-h

Re: [PATCH 10/11] serial: make uart_console_write->putchar()'s character a char

[kernel test robot]

Hi Jiri,

I love your patch! Yet something to improve:

[auto build test ERROR on tty/tty-testing]
[also build test ERROR on v5.17-rc1 next-20220124]
[cannot apply to shawnguo/for-next davem-sparc/master]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Jiri-Slaby/TTY-patches-for-5-18/20220124-151758
base:   https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git tty-testing
config: arc-randconfig-r043-20220124 (https://download.01.org/0day-ci/archive/20220125/202201250004.SHBbOjs3-lkp@intel.com/config)
compiler: arc-elf-gcc (GCC) 11.2.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/45520d4f6db241db0b77f41162adba4a9977956c
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Jiri-Slaby/TTY-patches-for-5-18/20220124-151758
        git checkout 45520d4f6db241db0b77f41162adba4a9977956c
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=arc SHELL=/bin/bash drivers/tty/serial/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   drivers/tty/serial/omap-serial.c: In function 'serial_omap_console_write':
>> drivers/tty/serial/omap-serial.c:1272:49: error: passing argument 4 of 'uart_console_write' from incompatible pointer type [-Werror=incompatible-pointer-types]
    1272 |         uart_console_write(&up->port, s, count, serial_omap_console_putchar);
         |                                                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~
         |                                                 |
         |                                                 void (*)(struct uart_port *, int)
   In file included from drivers/tty/serial/omap-serial.c:30:
   include/linux/serial_core.h:402:32: note: expected 'void (*)(struct uart_port *, char)' but argument is of type 'void (*)(struct uart_port *, int)'
     402 |                         void (*putchar)(struct uart_port *, char));
         |                         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   cc1: some warnings being treated as errors


vim +/uart_console_write +1272 drivers/tty/serial/omap-serial.c

b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1248  
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1249  static void
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1250  serial_omap_console_write(struct console *co, const char *s,
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1251  		unsigned int count)
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1252  {
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1253  	struct uart_omap_port *up = serial_omap_console_ports[co->index];
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1254  	unsigned long flags;
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1255  	unsigned int ier;
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1256  	int locked = 1;
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1257  
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1258  	local_irq_save(flags);
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1259  	if (up->port.sysrq)
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1260  		locked = 0;
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1261  	else if (oops_in_progress)
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1262  		locked = spin_trylock(&up->port.lock);
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1263  	else
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1264  		spin_lock(&up->port.lock);
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1265  
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1266  	/*
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1267  	 * First save the IER then disable the interrupts
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1268  	 */
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1269  	ier = serial_in(up, UART_IER);
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1270  	serial_out(up, UART_IER, 0);
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1271  
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27 @1272  	uart_console_write(&up->port, s, count, serial_omap_console_putchar);
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1273  
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1274  	/*
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1275  	 * Finally, wait for transmitter to become empty
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1276  	 * and restore the IER
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1277  	 */
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1278  	wait_for_xmitr(up);
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1279  	serial_out(up, UART_IER, ier);
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1280  	/*
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1281  	 * The receive handling will happen properly because the
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1282  	 * receive ready bit will still be set; it is not cleared
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1283  	 * on read.  However, modem control will not, we must
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1284  	 * call it if we have saved something in the saved flags
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1285  	 * while processing with interrupts off.
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1286  	 */
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1287  	if (up->msr_saved_flags)
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1288  		check_modem_status(up);
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1289  
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1290  	if (locked)
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1291  		spin_unlock(&up->port.lock);
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1292  	local_irq_restore(flags);
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1293  }
b612633b592807 drivers/serial/omap-serial.c Govindraj.R 2010-09-27  1294  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

Re: [PATCH 10/11] serial: make uart_console_write->putchar()'s character a char

[Maciej W. Rozycki]

On Mon, 24 Jan 2022, Jiri Slaby wrote:

> diff --git a/drivers/tty/serial/dz.c b/drivers/tty/serial/dz.c
> index e9edabc5a211..3493e201d67f 100644
> --- a/drivers/tty/serial/dz.c
> +++ b/drivers/tty/serial/dz.c
> @@ -802,7 +802,7 @@ static void __init dz_init_ports(void)
>   * restored.  Welcome to the world of PDP-11!
>   * -------------------------------------------------------------------
>   */
> -static void dz_console_putchar(struct uart_port *uport, int ch)
> +static void dz_console_putchar(struct uart_port *uport, char ch)
>  {
>  	struct dz_port *dport = to_dport(uport);
>  	unsigned long flags;

 Hmm, this is unsafe, because on the MIPS target the lone `char' type is 
signed and therefore a call to `->putchar' will see `ch' sign-extended 
from bit #7 to the width of the argument register used.  Which means that 
if a character is sent to the console that has its bit #7 set, then the 
call to:

		dz_out(dport, DZ_TDR, ch);

i.e.:

static void dz_out(struct dz_port *dport, unsigned offset, u16 value)

will send a value to DZ_TDR with bits #15:8 set to all-ones.  And bits 
#11:8 there are the BREAK control bits, active high, for serial lines #3:0 
respectively.

 We could handle this with a preparatory change by calling:

		dz_out(dport, DZ_TDR, ch & 0xffu);

instead, but perhaps `->putchar' should simply take `unsigned char' or 
maybe even `u8' as its third argument?

> diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
> index c58cc142d23f..68e62703eaa6 100644
> --- a/include/linux/serial_core.h
> +++ b/include/linux/serial_core.h
> @@ -399,7 +399,7 @@ int uart_set_options(struct uart_port *port, struct console
> *co, int baud,
>  struct tty_driver *uart_console_device(struct console *co, int *index);
>  void uart_console_write(struct uart_port *port, const char *s,
>  			unsigned int count,
> -			void (*putchar)(struct uart_port *, int));
> +			void (*putchar)(struct uart_port *, char));
>  
>  /*
>   * Port/driver registration/removal

 I.e.:

			void (*putchar)(struct uart_port *, unsigned char));

I can see we get it right already with:

	unsigned char		x_char;			/* xon/xoff char */

and for `dz_transmit_chars' we have:

	unsigned char tmp;
[...]
	tmp = xmit->buf[xmit->tail];
	xmit->tail = (xmit->tail + 1) & (DZ_XMIT_SIZE - 1);
	dz_out(dport, DZ_TDR, tmp);

(because `struct circ_buf' is generic and not limited to unsigned buffer 
contents interpretation; it's not clear to me if that has been intended 
though).

  Maciej

Re: [PATCH 10/11] serial: make uart_console_write->putchar()'s character a char

[Jiri Slaby]

On 26. 01. 22, 18:57, Maciej W. Rozycki wrote:
> On Mon, 24 Jan 2022, Jiri Slaby wrote:
> 
>> diff --git a/drivers/tty/serial/dz.c b/drivers/tty/serial/dz.c
>> index e9edabc5a211..3493e201d67f 100644
>> --- a/drivers/tty/serial/dz.c
>> +++ b/drivers/tty/serial/dz.c
>> @@ -802,7 +802,7 @@ static void __init dz_init_ports(void)
>>    * restored.  Welcome to the world of PDP-11!
>>    * -------------------------------------------------------------------
>>    */
>> -static void dz_console_putchar(struct uart_port *uport, int ch)
>> +static void dz_console_putchar(struct uart_port *uport, char ch)
>>   {
>>   	struct dz_port *dport = to_dport(uport);
>>   	unsigned long flags;
> 
>   Hmm, this is unsafe, because on the MIPS target the lone `char' type is
> signed and therefore a call to `->putchar' will see `ch' sign-extended
> from bit #7 to the width of the argument register used.  Which means that
> if a character is sent to the console that has its bit #7 set, then the
> call to:
> 
> 		dz_out(dport, DZ_TDR, ch);
> 
> i.e.:
> 
> static void dz_out(struct dz_port *dport, unsigned offset, u16 value)
> 
> will send a value to DZ_TDR with bits #15:8 set to all-ones.  And bits
> #11:8 there are the BREAK control bits, active high, for serial lines #3:0
> respectively.
> 
>   We could handle this with a preparatory change by calling:
> 
> 		dz_out(dport, DZ_TDR, ch & 0xffu);
> 
> instead, but perhaps `->putchar' should simply take `unsigned char' or
> maybe even `u8' as its third argument?
> 
>> diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
>> index c58cc142d23f..68e62703eaa6 100644
>> --- a/include/linux/serial_core.h
>> +++ b/include/linux/serial_core.h
>> @@ -399,7 +399,7 @@ int uart_set_options(struct uart_port *port, struct console
>> *co, int baud,
>>   struct tty_driver *uart_console_device(struct console *co, int *index);
>>   void uart_console_write(struct uart_port *port, const char *s,
>>   			unsigned int count,
>> -			void (*putchar)(struct uart_port *, int));
>> +			void (*putchar)(struct uart_port *, char));
>>   
>>   /*
>>    * Port/driver registration/removal
> 
>   I.e.:
> 
> 			void (*putchar)(struct uart_port *, unsigned char));
> 
> I can see we get it right already with:
> 
> 	unsigned char		x_char;			/* xon/xoff char */
> 
> and for `dz_transmit_chars' we have:
> 
> 	unsigned char tmp;
> [...]
> 	tmp = xmit->buf[xmit->tail];
> 	xmit->tail = (xmit->tail + 1) & (DZ_XMIT_SIZE - 1);
> 	dz_out(dport, DZ_TDR, tmp);
> 
> (because `struct circ_buf' is generic and not limited to unsigned buffer
> contents interpretation; it's not clear to me if that has been intended
> though).

Thanks, good point. I was considering unsigned char and concluded not go 
that path right now as the rest of the console world uses char -- 
starting from the printk code. OTOH the whole uart world uses 'unsigned 
char' except that circ_buf. But I am phasing circ_buf out in favor of 
kfifo+unsigned-char anyway.

So let me switch the whole uart (the console code in particular) to an 
unsigned world. Meaning printk will pass char, uart will receive it as 
unsigned char and will keep it unsigned in all cases.

thanks,
-- 
js
suse labs

[PATCH 11/11] serial: mcf: use helpers in mcf_tx_chars()

[Jiri Slaby]

Use uart_circ_empty() instead of open-coding it via xmit->head & tail.
Use preexisting mcf_stop_tx() to avoid stop-tx code duplication.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/tty/serial/mcf.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/tty/serial/mcf.c b/drivers/tty/serial/mcf.c
index c7cec7d03620..2aec62b5d6c4 100644
--- a/drivers/tty/serial/mcf.c
+++ b/drivers/tty/serial/mcf.c
@@ -338,7 +338,7 @@ static void mcf_tx_chars(struct mcf_uart *pp)
 	}
 
 	while (readb(port->membase + MCFUART_USR) & MCFUART_USR_TXREADY) {
-		if (xmit->head == xmit->tail)
+		if (uart_circ_empty(xmit))
 			break;
 		writeb(xmit->buf[xmit->tail], port->membase + MCFUART_UTB);
 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE -1);
@@ -348,9 +348,8 @@ static void mcf_tx_chars(struct mcf_uart *pp)
 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 		uart_write_wakeup(port);
 
-	if (xmit->head == xmit->tail) {
-		pp->imr &= ~MCFUART_UIR_TXREADY;
-		writeb(pp->imr, port->membase + MCFUART_UIMR);
+	if (uart_circ_empty(xmit)) {
+		mcf_stop_tx(port);
 		/* Disable TX to negate RTS automatically */
 		if (port->rs485.flags & SER_RS485_ENABLED)
 			writeb(MCFUART_UCR_TXDISABLE,
-- 
2.34.1