Problem with serial.c introduced in 2.4.15

Problem with serial.c introduced in 2.4.15

[Christian Asam]

After having found that my VM-Problem (USB/MOD) was due to an old 
kernel I upgraded to 2.4.18 and found that I couldn't use my digitizer 
board (Genius) with gpm(genitizer) anymoure.
I tracked it down to a change made from 2.4.14 to 2.4.15:

drivers/char/serial.c:
#if 0   /*
         * !!! ignore all characters if CREAD is not set
         */
        if ((cflag & CREAD) == 0)
                info->ignore_status_mask |= UART_LSR_DR;
#endif

The #if 0 and #endif was removed in 2.4.15 and somehow that breaks 
gpm/genitizer. Having added the "commenting out through $if 0" the 
tablet works fine again and deactivating the appropriate line in 2.4.18 
also works.

cu

Re: Problem with serial.c introduced in 2.4.15

[Russell King]

On Sun, Mar 24, 2002 at 05:57:08PM +0100, Christian Asam wrote:
> The #if 0 and #endif was removed in 2.4.15 and somehow that breaks 
> gpm/genitizer. Having added the "commenting out through $if 0" the 
> tablet works fine again and deactivating the appropriate line in 2.4.18 
> also works.

It sounds like gpm is buggy.  If an application turns off the CREAD flag
and expects to read characters from a TTY, then its asking too much. 8)

       [-]cread
              allow input to be received

-- 
Russell King (rmk@arm.linux.org.uk)                The developer of ARM Linux
             http://www.arm.linux.org.uk/personal/aboutme.html

Re: Problem with serial.c introduced in 2.4.15

[Bernd Eckenfels]

In article <E16pBIs-00024N-00@mrvdom03.kundenserver.de> you wrote:
> The #if 0 and #endif was removed in 2.4.15 and somehow that breaks 
> gpm/genitizer. Having added the "commenting out through $if 0" the 
> tablet works fine again and deactivating the appropriate line in 2.4.18 
> also works.

Probably stty CREAD < /dev/ttyS0  will help (or whatever your tty is) Looks
like a bug in gpm, which is not setting the cread flag.

Greetings
Bernd

Problem with serial.c introduced in 2.4.15

[Christian Asam]

After having found out that a too old kernel caused my problem with 
writing to slow devices I had the problem that my serial digitizer 
(Genius using gpm/genitizer) didn't work with 2.4.18. I tracked it down 
to a change made in 1.4.15:
drivers/char/serial.c:
#if 0   /*
         * !!! ignore all characters if CREAD is not set
         */
        if ((cflag & CREAD) == 0)
                info->ignore_status_mask |= UART_LSR_DR;
#endif

In 2.4.15 the #if 0 and #endif was removed and somehow that manages to 
break gpm/genitizer. I then added the #if 0/#endif to "remove" that 
statement in 2.4.18 and the tablet works with 2.4.18 too.

cu