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* [PATCH v2] serial: omap: fix the reciever line error case
@ 2012-09-21 14:37 Shubhrajyoti D
  2012-09-21 16:01 ` Felipe Balbi
  2012-09-21 21:46 ` Kevin Hilman
  0 siblings, 2 replies; 3+ messages in thread
From: Shubhrajyoti D @ 2012-09-21 14:37 UTC (permalink / raw)
  To: linux-arm-kernel

This patch does the following
- In case of errors if there least one data character in the RX FIFO
read it otherwise it may stall the receiver.

This is recommended in the interrupt reset method in the table 23-246 of
the omap4 TRM.

Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti•com>
---
- Tested on omap4sdp.
- pm tested hitting off in idle and suspend.
- v2 changes update the changelogs.
- Also remove the dummy check as FE , PE , BI and OE are the only
receiver errors.

 drivers/tty/serial/omap-serial.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index a0d4460..4fea16b 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -334,6 +334,10 @@ static unsigned int check_modem_status(struct uart_omap_port *up)
 static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr)
 {
 	unsigned int flag;
+	unsigned char ch = 0;
+
+	if (likely(lsr & UART_LSR_DR))
+		ch = serial_in(up, UART_RX);
 
 	up->port.icount.rx++;
 	flag = TTY_NORMAL;
-- 
1.7.5.4

^ permalink raw reply related	[flat|nested] 3+ messages in thread

* [PATCH v2] serial: omap: fix the reciever line error case
  2012-09-21 14:37 [PATCH v2] serial: omap: fix the reciever line error case Shubhrajyoti D
@ 2012-09-21 16:01 ` Felipe Balbi
  2012-09-21 21:46 ` Kevin Hilman
  1 sibling, 0 replies; 3+ messages in thread
From: Felipe Balbi @ 2012-09-21 16:01 UTC (permalink / raw)
  To: linux-arm-kernel

On Fri, Sep 21, 2012 at 08:07:19PM +0530, Shubhrajyoti D wrote:
> This patch does the following
> - In case of errors if there least one data character in the RX FIFO
> read it otherwise it may stall the receiver.
> 
> This is recommended in the interrupt reset method in the table 23-246 of
> the omap4 TRM.
> 
> Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti•com>

FWIW:

Reviewed-by: Felipe Balbi <balbi@ti•com>

> ---
> - Tested on omap4sdp.
> - pm tested hitting off in idle and suspend.
> - v2 changes update the changelogs.
> - Also remove the dummy check as FE , PE , BI and OE are the only
> receiver errors.
> 
>  drivers/tty/serial/omap-serial.c |    4 ++++
>  1 files changed, 4 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
> index a0d4460..4fea16b 100644
> --- a/drivers/tty/serial/omap-serial.c
> +++ b/drivers/tty/serial/omap-serial.c
> @@ -334,6 +334,10 @@ static unsigned int check_modem_status(struct uart_omap_port *up)
>  static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr)
>  {
>  	unsigned int flag;
> +	unsigned char ch = 0;
> +
> +	if (likely(lsr & UART_LSR_DR))
> +		ch = serial_in(up, UART_RX);
>  
>  	up->port.icount.rx++;
>  	flag = TTY_NORMAL;
> -- 
> 1.7.5.4
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-omap" in
> the body of a message to majordomo at vger.kernel.org
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-- 
balbi
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^ permalink raw reply	[flat|nested] 3+ messages in thread

* [PATCH v2] serial: omap: fix the reciever line error case
  2012-09-21 14:37 [PATCH v2] serial: omap: fix the reciever line error case Shubhrajyoti D
  2012-09-21 16:01 ` Felipe Balbi
@ 2012-09-21 21:46 ` Kevin Hilman
  1 sibling, 0 replies; 3+ messages in thread
From: Kevin Hilman @ 2012-09-21 21:46 UTC (permalink / raw)
  To: linux-arm-kernel

Shubhrajyoti D <shubhrajyoti@ti•com> writes:

> This patch does the following
> - In case of errors if there least one data character in the RX FIFO
> read it otherwise it may stall the receiver.
>
> This is recommended in the interrupt reset method in the table 23-246 of
> the omap4 TRM.
>
> Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti•com>
> ---
> - Tested on omap4sdp.
> - pm tested hitting off in idle and suspend.
> - v2 changes update the changelogs.
> - Also remove the dummy check as FE , PE , BI and OE are the only
> receiver errors.

Tested-by: Kevin Hilman <khilman@ti•com>

This one also makes the regression I was seeing on 3530/Overo disappear.

Thanks,

Kevin

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2012-09-21 21:46 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2012-09-21 14:37 [PATCH v2] serial: omap: fix the reciever line error case Shubhrajyoti D
2012-09-21 16:01 ` Felipe Balbi
2012-09-21 21:46 ` Kevin Hilman

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