[PATCH] 8250 serial console update uart_8250_port ier

[PATCH] 8250 serial console update uart_8250_port ier

[Kumar Gala]

On some embedded PowerPC (MPC834x) systems an extra byte would some times be
required to flush data out of the fifo. serial8250_console_write() was updating
the IER in hardware withouth also updating the copy in uart_8250_port. This
causes issues functions like serial8250_start_tx() and __stop_tx() to misbehave.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

---
commit 0614711f0208f50e81d55283add8ae41bc332fc7
tree 1da4194744b9ca1fe59976c6ebffccfee40299eb
parent 45a38d42185df3e328e35e5167f2bfe181361db9
author Kumar Gala <galak@kernel.crashing.org> Tue, 07 Feb 2006 08:51:26 -0600
committer Kumar Gala <galak@kernel.crashing.org> Tue, 07 Feb 2006 08:51:26 -0600

 drivers/serial/8250.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index 179c1f0..b1fc97d 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -2229,6 +2229,7 @@ serial8250_console_write(struct console 
 	 *	and restore the IER
 	 */
 	wait_for_xmitr(up, BOTH_EMPTY);
+	up->ier |= UART_IER_THRI;
 	serial_out(up, UART_IER, ier | UART_IER_THRI);
 }
 

Re: [PATCH] 8250 serial console update uart_8250_port ier

[Kumar Gala]

Russell,

If you are ok with this can we make sure this gets to Linus for 2.6.16

thanks

- kumar

On Feb 7, 2006, at 8:52 AM, Kumar Gala wrote:

> On some embedded PowerPC (MPC834x) systems an extra byte would some  
> times be
> required to flush data out of the fifo. serial8250_console_write()  
> was updating
> the IER in hardware withouth also updating the copy in  
> uart_8250_port. This
> causes issues functions like serial8250_start_tx() and __stop_tx()  
> to misbehave.
>
> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
>
> ---
> commit 0614711f0208f50e81d55283add8ae41bc332fc7
> tree 1da4194744b9ca1fe59976c6ebffccfee40299eb
> parent 45a38d42185df3e328e35e5167f2bfe181361db9
> author Kumar Gala <galak@kernel.crashing.org> Tue, 07 Feb 2006  
> 08:51:26 -0600
> committer Kumar Gala <galak@kernel.crashing.org> Tue, 07 Feb 2006  
> 08:51:26 -0600
>
>  drivers/serial/8250.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
> index 179c1f0..b1fc97d 100644
> --- a/drivers/serial/8250.c
> +++ b/drivers/serial/8250.c
> @@ -2229,6 +2229,7 @@ serial8250_console_write(struct console
>  	 *	and restore the IER
>  	 */
>  	wait_for_xmitr(up, BOTH_EMPTY);
> +	up->ier |= UART_IER_THRI;
>  	serial_out(up, UART_IER, ier | UART_IER_THRI);
>  }
>
>
> -
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Re: [PATCH] 8250 serial console update uart_8250_port ier

[Russell King]

On Tue, Feb 07, 2006 at 08:52:03AM -0600, Kumar Gala wrote:
> On some embedded PowerPC (MPC834x) systems an extra byte would some times be
> required to flush data out of the fifo. serial8250_console_write() was updating
> the IER in hardware withouth also updating the copy in uart_8250_port. This
> causes issues functions like serial8250_start_tx() and __stop_tx() to misbehave.

Applied, thanks.

-- 
Russell King
 Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
 maintainer of:  2.6 Serial core