Help with serial synths in 4.X kernels

[covici at ccs.covici.com]

But even with your patch, serial port access is not  available with
speakup.  Also, if you set 8250.nr_uarts=0 what happens  to other serial
ports you may need for modems, or other applications?

Samuel Thibault <samuel.thibault at ens-lyon.org> wrote:

> Hello,
> 
> covici at ccs.covici.com, on Tue 23 Feb 2016 10:05:22 -0500, wrote:
> > Do you have the serialio.c patched to comment out the return null in
> > around line 42?
> 
> Just wondering...
> 
> Is it known that passing
> 
> 8250.nr_uarts=0
> 
> as a kernel command-line parameter has actually the same effect?  It'll
> just prevent the normal serial driver from taking the ports, and thus
> speakup will not have any trouble accessing them.
> 
> About the patches I have sent to the linux kernel mailing list, only the
> attached one is needed to fix serial port access.
> 
> About proper serial port access, somebody from the Outreachy intern
> program is currently having a look.
> 
> Samuel
> Subject: [PATCH] Staging: speakup: Fix getting port information
> 
> Commit f79b0d9c223c ("staging: speakup: Fixed warning <linux/serial.h>
> instead of <asm/serial.h>") broke the port information in the speakup
> driver: SERIAL_PORT_DFNS only gets defined if asm/serial.h is included,
> and no other header includes asm/serial.h.
> 
> We here make sure serialio.c does get the arch-specific definition of
> SERIAL_PORT_DFNS from asm/serial.h, if any.
> 
> Along the way, this makes sure that we do have information for the
> requested serial port number (index)
> 
> Signed-off-by: Samuel Thibault <samuel.thibault at ens-lyon.org>
> Fixes: f79b0d9c223c ("staging: speakup: Fixed warning <linux/serial.h> instead of <asm/serial.h>")
> 
> --- a/drivers/staging/speakup/serialio.c
> +++ b/drivers/staging/speakup/serialio.c
> @@ -6,6 +6,11 @@
>  #include "spk_priv.h"
>  #include "serialio.h"
>  
> +#include <linux/serial_core.h>
> +/* WARNING:  Do not change this to <linux/serial.h> without testing that
> + * SERIAL_PORT_DFNS does get defined to the appropriate value. */
> +#include <asm/serial.h>
> +
>  #ifndef SERIAL_PORT_DFNS
>  #define SERIAL_PORT_DFNS
>  #endif
> @@ -23,9 +28,15 @@ const struct old_serial_port *spk_serial
>  	int baud = 9600, quot = 0;
>  	unsigned int cval = 0;
>  	int cflag = CREAD | HUPCL | CLOCAL | B9600 | CS8;
> -	const struct old_serial_port *ser = rs_table + index;
> +	const struct old_serial_port *ser;
>  	int err;
>  
> +	if (index >= ARRAY_SIZE(rs_table)) {
> +		pr_info("no port info for ttyS%d\n", index);
> +		return NULL;
> +	}
> +	ser = rs_table + index;
> +
>  	/*	Divisor, bytesize and parity */
>  	quot = ser->baud_base / baud;
>  	cval = cflag & (CSIZE | CSTOPB);
> _______________________________________________
> Speakup mailing list
> Speakup at linux-speakup.org
> http://linux-speakup.org/cgi-bin/mailman/listinfo/speakup

-- 
Your life is like a penny.  You're going to lose it.  The question is:
How do
you spend it?

         John Covici
         covici at ccs.covici.com