diff mbox

[PATCH/RFC] serial: sh-sci: Add overrun handling of SCIFA and SCIFB

Message ID 1426429695-2993-1-git-send-email-ykaneko0929@gmail.com (mailing list archive)
State Superseded
Delegated to: Geert Uytterhoeven
Headers show

Commit Message

Yoshihiro Kaneko March 15, 2015, 2:28 p.m. UTC 
From: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>

SCIFA and SCIFB can detect the overrun, but it does not support.
This adds overrun handling of SCIFA and SCIFB.

Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
---

This patch is based on the tty-next branch of Greg Kroah-Hartman's tty
tree.

 drivers/tty/serial/sh-sci.c | 34 +++++++++++++++++++++++-----------
 1 file changed, 23 insertions(+), 11 deletions(-)

Comments

Sergei Shtylyov March 15, 2015, 3:28 p.m. UTC | #1 
Hello.

On 3/15/2015 5:28 PM, Yoshihiro Kaneko wrote:

> From: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>

> SCIFA and SCIFB can detect the overrun, but it does not support.
> This adds overrun handling of SCIFA and SCIFB.

> Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
> Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
> ---

> This patch is based on the tty-next branch of Greg Kroah-Hartman's tty
> tree.

>   drivers/tty/serial/sh-sci.c | 34 +++++++++++++++++++++++-----------
>   1 file changed, 23 insertions(+), 11 deletions(-)

> diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
> index 5b50c79..d165b21 100644
> --- a/drivers/tty/serial/sh-sci.c
> +++ b/drivers/tty/serial/sh-sci.c
> @@ -844,14 +844,26 @@ static int sci_handle_fifo_overrun(struct uart_port *port)
>   	struct tty_port *tport = &port->state->port;
>   	struct sci_port *s = to_sci_port(port);
>   	struct plat_sci_reg *reg;
> -	int copied = 0;
> +	int copied = 0, offset;
> +	u16 status, bit;
> +
> +	if (port->type == PORT_SCIF || port->type == PORT_HSCIF)
> +		offset = SCLSR;
> +	else if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
> +		offset = SCxSR;
> +	else
> +		return 0;

    This is asking to be a *switch* statement instead.

[...]
> @@ -1005,7 +1016,10 @@ static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
>   	ssr_status = serial_port_in(port, SCxSR);
>   	scr_status = serial_port_in(port, SCSCR);
>   	if (port->type == PORT_SCIF || port->type == PORT_HSCIF)
> -		slr_status = serial_port_in(port, SCLSR);
> +		orer_status = serial_port_in(port, SCLSR);
> +	else if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
> +		orer_status = ssr_status;

    This one too...

[...]

WBR, Sergei

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Yoshihiro Kaneko March 16, 2015, 1:55 p.m. UTC | #2 
Hello,

2015-03-16 0:28 GMT+09:00 Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>:
> Hello.
>
> On 3/15/2015 5:28 PM, Yoshihiro Kaneko wrote:
>
>> From: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
>
>
>> SCIFA and SCIFB can detect the overrun, but it does not support.
>> This adds overrun handling of SCIFA and SCIFB.
>
>
>> Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
>> Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
>> ---
>
>
>> This patch is based on the tty-next branch of Greg Kroah-Hartman's tty
>> tree.
>
>
>>   drivers/tty/serial/sh-sci.c | 34 +++++++++++++++++++++++-----------
>>   1 file changed, 23 insertions(+), 11 deletions(-)
>
>
>> diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
>> index 5b50c79..d165b21 100644
>> --- a/drivers/tty/serial/sh-sci.c
>> +++ b/drivers/tty/serial/sh-sci.c
>> @@ -844,14 +844,26 @@ static int sci_handle_fifo_overrun(struct uart_port
>> *port)
>>         struct tty_port *tport = &port->state->port;
>>         struct sci_port *s = to_sci_port(port);
>>         struct plat_sci_reg *reg;
>> -       int copied = 0;
>> +       int copied = 0, offset;
>> +       u16 status, bit;
>> +
>> +       if (port->type == PORT_SCIF || port->type == PORT_HSCIF)
>> +               offset = SCLSR;
>> +       else if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
>> +               offset = SCxSR;
>> +       else
>> +               return 0;
>
>
>    This is asking to be a *switch* statement instead.

I certainly think so.

>
> [...]
>>
>> @@ -1005,7 +1016,10 @@ static irqreturn_t sci_mpxed_interrupt(int irq,
>> void *ptr)
>>         ssr_status = serial_port_in(port, SCxSR);
>>         scr_status = serial_port_in(port, SCSCR);
>>         if (port->type == PORT_SCIF || port->type == PORT_HSCIF)
>> -               slr_status = serial_port_in(port, SCLSR);
>> +               orer_status = serial_port_in(port, SCLSR);
>> +       else if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
>> +               orer_status = ssr_status;
>
>
>    This one too...

I also revise this one.


Thanks,
Kaneko

>
> [...]
>
> WBR, Sergei
>
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diff mbox

Patch

diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 5b50c79..d165b21 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -844,14 +844,26 @@  static int sci_handle_fifo_overrun(struct uart_port *port)
 	struct tty_port *tport = &port->state->port;
 	struct sci_port *s = to_sci_port(port);
 	struct plat_sci_reg *reg;
-	int copied = 0;
+	int copied = 0, offset;
+	u16 status, bit;
+
+	if (port->type == PORT_SCIF || port->type == PORT_HSCIF)
+		offset = SCLSR;
+	else if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
+		offset = SCxSR;
+	else
+		return 0;
 
-	reg = sci_getreg(port, SCLSR);
+	reg = sci_getreg(port, offset);
 	if (!reg->size)
 		return 0;
 
-	if ((serial_port_in(port, SCLSR) & (1 << s->overrun_bit))) {
-		serial_port_out(port, SCLSR, 0);
+	status = serial_port_in(port, offset);
+	bit = 1 << s->overrun_bit;
+
+	if (status & bit) {
+		status &= ~bit;
+		serial_port_out(port, offset, status);
 
 		port->icount.overrun++;
 
@@ -996,8 +1008,7 @@  static inline unsigned long port_rx_irq_mask(struct uart_port *port)
 
 static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
 {
-	unsigned short ssr_status, scr_status, err_enabled;
-	unsigned short slr_status = 0;
+	unsigned short ssr_status, scr_status, err_enabled, orer_status = 0;
 	struct uart_port *port = ptr;
 	struct sci_port *s = to_sci_port(port);
 	irqreturn_t ret = IRQ_NONE;
@@ -1005,7 +1016,10 @@  static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
 	ssr_status = serial_port_in(port, SCxSR);
 	scr_status = serial_port_in(port, SCSCR);
 	if (port->type == PORT_SCIF || port->type == PORT_HSCIF)
-		slr_status = serial_port_in(port, SCLSR);
+		orer_status = serial_port_in(port, SCLSR);
+	else if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
+		orer_status = ssr_status;
+
 	err_enabled = scr_status & port_rx_irq_mask(port);
 
 	/* Tx Interrupt */
@@ -1033,10 +1047,8 @@  static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
 		ret = sci_br_interrupt(irq, ptr);
 
 	/* Overrun Interrupt */
-	if (port->type == PORT_SCIF || port->type == PORT_HSCIF) {
-		if (slr_status & 0x01)
-			sci_handle_fifo_overrun(port);
-	}
+	if (orer_status & (1 << s->overrun_bit))
+		sci_handle_fifo_overrun(port);
 
 	return ret;
 }