Re: [PATCH] 8250: make probing for TXEN bug a config option

2007-03-14 Thread Vitaly Wool

On 2/14/07, Andrew Morton <[EMAIL PROTECTED]> wrote:


I think this should be a module option/boot parameter, not a config-time
option.


NM, the recent changes in 8250 driver eliminated the need for this patch :)

Vitaly
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Re: [PATCH] 8250: make probing for TXEN bug a config option

2007-03-14 Thread Vitaly Wool

On 2/14/07, Andrew Morton [EMAIL PROTECTED] wrote:


I think this should be a module option/boot parameter, not a config-time
option.


NM, the recent changes in 8250 driver eliminated the need for this patch :)

Vitaly
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Re: [PATCH] 8250: make probing for TXEN bug a config option

2007-02-14 Thread Andrew Morton
On Wed, 14 Feb 2007 05:41:53 -0800
"Vitaly Wool" <[EMAIL PROTECTED]> wrote:

> On 2/14/07, Andrew Morton <[EMAIL PROTECTED]> wrote:
> > On Wed, 14 Feb 2007 11:37:52 +0300 "Vitaly Wool" <[EMAIL PROTECTED]> wrote:
> > > Hmm, why? I can't think of a platform where one 8250-compatible UART is
> > > problematic and another isn't :)
> > >
> >
> > Is it not possible that the same kernel package can be installed on systems
> > which do and don't need this feature?  If so, we don't want to force the
> > provider of that package to create two packages.
> >
> > That, plus the chances of the package creator actually knowing about this
> > option aren't great.
> >
> > Generally, if it can be done at runtime it is better to do so, no?
> 
> Okay, yes, I see your point. The same kernel might actually be
> supporting several machines.
> 
> But having that as a config option doesn't look too attractive to me.
> What about adding a new flag to plat_serial 8250 stuff instead?

plat_serial8250_port.flags?  Dunno, I'm unfamiliar with it.  That seems to be 
how
the share_irqs option is handled.
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Re: [PATCH] 8250: make probing for TXEN bug a config option

2007-02-14 Thread Vitaly Wool

On 2/14/07, Andrew Morton <[EMAIL PROTECTED]> wrote:

On Wed, 14 Feb 2007 11:37:52 +0300 "Vitaly Wool" <[EMAIL PROTECTED]> wrote:
> Hmm, why? I can't think of a platform where one 8250-compatible UART is
> problematic and another isn't :)
>

Is it not possible that the same kernel package can be installed on systems
which do and don't need this feature?  If so, we don't want to force the
provider of that package to create two packages.

That, plus the chances of the package creator actually knowing about this
option aren't great.

Generally, if it can be done at runtime it is better to do so, no?


Okay, yes, I see your point. The same kernel might actually be
supporting several machines.

But having that as a config option doesn't look too attractive to me.
What about adding a new flag to plat_serial 8250 stuff instead?

Vitaly
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Re: [PATCH] 8250: make probing for TXEN bug a config option

2007-02-14 Thread Andrew Morton
On Wed, 14 Feb 2007 11:37:52 +0300 "Vitaly Wool" <[EMAIL PROTECTED]> wrote:

> On 2/14/07, Andrew Morton <[EMAIL PROTECTED]> wrote:
> >
> > I think this should be a module option/boot parameter, not a config-time
> > option.
> >
> >
> Hmm, why? I can't think of a platform where one 8250-compatible UART is
> problematic and another isn't :)
> 

Is it not possible that the same kernel package can be installed on systems
which do and don't need this feature?  If so, we don't want to force the
provider of that package to create two packages.

That, plus the chances of the package creator actually knowing about this
option aren't great.

Generally, if it can be done at runtime it is better to do so, no?
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Re: [PATCH] 8250: make probing for TXEN bug a config option

2007-02-14 Thread Andrew Morton
On Wed, 14 Feb 2007 11:37:52 +0300 Vitaly Wool [EMAIL PROTECTED] wrote:

 On 2/14/07, Andrew Morton [EMAIL PROTECTED] wrote:
 
  I think this should be a module option/boot parameter, not a config-time
  option.
 
 
 Hmm, why? I can't think of a platform where one 8250-compatible UART is
 problematic and another isn't :)
 

Is it not possible that the same kernel package can be installed on systems
which do and don't need this feature?  If so, we don't want to force the
provider of that package to create two packages.

That, plus the chances of the package creator actually knowing about this
option aren't great.

Generally, if it can be done at runtime it is better to do so, no?
-
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Re: [PATCH] 8250: make probing for TXEN bug a config option

2007-02-14 Thread Vitaly Wool

On 2/14/07, Andrew Morton [EMAIL PROTECTED] wrote:

On Wed, 14 Feb 2007 11:37:52 +0300 Vitaly Wool [EMAIL PROTECTED] wrote:
 Hmm, why? I can't think of a platform where one 8250-compatible UART is
 problematic and another isn't :)


Is it not possible that the same kernel package can be installed on systems
which do and don't need this feature?  If so, we don't want to force the
provider of that package to create two packages.

That, plus the chances of the package creator actually knowing about this
option aren't great.

Generally, if it can be done at runtime it is better to do so, no?


Okay, yes, I see your point. The same kernel might actually be
supporting several machines.

But having that as a config option doesn't look too attractive to me.
What about adding a new flag to plat_serial 8250 stuff instead?

Vitaly
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Re: [PATCH] 8250: make probing for TXEN bug a config option

2007-02-14 Thread Andrew Morton
On Wed, 14 Feb 2007 05:41:53 -0800
Vitaly Wool [EMAIL PROTECTED] wrote:

 On 2/14/07, Andrew Morton [EMAIL PROTECTED] wrote:
  On Wed, 14 Feb 2007 11:37:52 +0300 Vitaly Wool [EMAIL PROTECTED] wrote:
   Hmm, why? I can't think of a platform where one 8250-compatible UART is
   problematic and another isn't :)
  
 
  Is it not possible that the same kernel package can be installed on systems
  which do and don't need this feature?  If so, we don't want to force the
  provider of that package to create two packages.
 
  That, plus the chances of the package creator actually knowing about this
  option aren't great.
 
  Generally, if it can be done at runtime it is better to do so, no?
 
 Okay, yes, I see your point. The same kernel might actually be
 supporting several machines.
 
 But having that as a config option doesn't look too attractive to me.
 What about adding a new flag to plat_serial 8250 stuff instead?

plat_serial8250_port.flags?  Dunno, I'm unfamiliar with it.  That seems to be 
how
the share_irqs option is handled.
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Re: [PATCH] 8250: make probing for TXEN bug a config option

2007-02-13 Thread Andrew Morton
On Tue, 26 Dec 2006 19:43:17 +0300 Vitaly Wool <[EMAIL PROTECTED]> wrote:

^^^  Sorry.

> Hello Andrew,
> 
> probing for UART_BUG_TXEN in 8250 driver leads to weird effects on some ARM 
> boards (pnx4008 for instance). That is, the driver detects  UART_BUG_TXEN 
> (though it apparently shouldn't) and it leads to symbol loss in console on 
> input (i. e. you input 'a' and you get nothing, then you input 'b' and you 
> get 'a', then you input 'c' and get 'b' and so on).
> 
> The patch below makes this very probing a configuration option turned on by 
> default.
> 
>  drivers/serial/8250.c  |5 -
>  drivers/serial/Kconfig |   10 ++
>  2 files changed, 14 insertions(+), 1 deletion(-)
> 
> Signed-off-by: Vitaly Wool <[EMAIL PROTECTED]>
> 
> diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
> index 51f3c73..cf3eb31 100644
> --- a/drivers/serial/8250.c
> +++ b/drivers/serial/8250.c
> @@ -1645,6 +1645,7 @@ static int serial8250_startup(struct uar
>  
>   serial8250_set_mctrl(>port, up->port.mctrl);
>  
> +#ifndef CONFIG_SERIAL_8250_DONT_TEST_BUG_TXEN
>   /*
>* Do a quick test to see if we receive an
>* interrupt when we enable the TX irq.
> @@ -1660,7 +1661,9 @@ static int serial8250_startup(struct uar
>   pr_debug("ttyS%d - enabling bad tx status 
> workarounds\n",
>port->line);
>   }
> - } else {
> + } else
> +#endif
> + {
>   up->bugs &= ~UART_BUG_TXEN;
>   }
>  
> diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
> index 2978c09..7efcaf3 100644
> --- a/drivers/serial/Kconfig
> +++ b/drivers/serial/Kconfig
> @@ -223,6 +223,16 @@ config SERIAL_8250_DETECT_IRQ
>  
> If unsure, say N.
>  
> +config SERIAL_8250_DONT_TEST_BUG_TXEN
> + bool "Don't probe for TXEN bug"
> + depends on SERIAL_8250_EXTENDED
> + help
> +   Say Y here if you don't want the kernel to probe for TXEN bug
> +   on your serial port and try to workaround it. It might lead to
> +   character loss on some boards, though this is quite a rare case.
> +
> +   If unsure, say N.
> +
>  config SERIAL_8250_RSA
>   bool "Support RSA serial ports"
>   depends on SERIAL_8250_EXTENDED

I think this should be a module option/boot parameter, not a config-time
option.

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Re: [PATCH] 8250: make probing for TXEN bug a config option

2007-02-13 Thread Andrew Morton
On Tue, 26 Dec 2006 19:43:17 +0300 Vitaly Wool [EMAIL PROTECTED] wrote:

^^^  Sorry.

 Hello Andrew,
 
 probing for UART_BUG_TXEN in 8250 driver leads to weird effects on some ARM 
 boards (pnx4008 for instance). That is, the driver detects  UART_BUG_TXEN 
 (though it apparently shouldn't) and it leads to symbol loss in console on 
 input (i. e. you input 'a' and you get nothing, then you input 'b' and you 
 get 'a', then you input 'c' and get 'b' and so on).
 
 The patch below makes this very probing a configuration option turned on by 
 default.
 
  drivers/serial/8250.c  |5 -
  drivers/serial/Kconfig |   10 ++
  2 files changed, 14 insertions(+), 1 deletion(-)
 
 Signed-off-by: Vitaly Wool [EMAIL PROTECTED]
 
 diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
 index 51f3c73..cf3eb31 100644
 --- a/drivers/serial/8250.c
 +++ b/drivers/serial/8250.c
 @@ -1645,6 +1645,7 @@ static int serial8250_startup(struct uar
  
   serial8250_set_mctrl(up-port, up-port.mctrl);
  
 +#ifndef CONFIG_SERIAL_8250_DONT_TEST_BUG_TXEN
   /*
* Do a quick test to see if we receive an
* interrupt when we enable the TX irq.
 @@ -1660,7 +1661,9 @@ static int serial8250_startup(struct uar
   pr_debug(ttyS%d - enabling bad tx status 
 workarounds\n,
port-line);
   }
 - } else {
 + } else
 +#endif
 + {
   up-bugs = ~UART_BUG_TXEN;
   }
  
 diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
 index 2978c09..7efcaf3 100644
 --- a/drivers/serial/Kconfig
 +++ b/drivers/serial/Kconfig
 @@ -223,6 +223,16 @@ config SERIAL_8250_DETECT_IRQ
  
 If unsure, say N.
  
 +config SERIAL_8250_DONT_TEST_BUG_TXEN
 + bool Don't probe for TXEN bug
 + depends on SERIAL_8250_EXTENDED
 + help
 +   Say Y here if you don't want the kernel to probe for TXEN bug
 +   on your serial port and try to workaround it. It might lead to
 +   character loss on some boards, though this is quite a rare case.
 +
 +   If unsure, say N.
 +
  config SERIAL_8250_RSA
   bool Support RSA serial ports
   depends on SERIAL_8250_EXTENDED

I think this should be a module option/boot parameter, not a config-time
option.

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