Line discipline

[Okash Khawaja]

Hi,

On Thu, Jan 26, 2017 at 8:33 AM, Samuel Thibault
<samuel.thibault at ens-lyon.org> wrote:
> Okash Khawaja, on Thu 26 Jan 2017 08:24:29 +0000, wrote:
>> >> +static void speakup_ldisc_close(struct tty_struct *tty)
>> >> +{
>> >> +    pr_warn("speakup_test_close()\n");
>> >
>> > Does it get called at speakup_dummy removal time?
>>
>> No
>
> Ok.  I guess what we are missing is some part of the rest of
> tty_release(). We notably seem to be lacking tty_ldisc_release(tty);
> between tty_unlock and tty_flush_works.

Added tty_ldisc_release() which resolved the problem. Also added
tty_ldisc_flush() before tty_ldisc_release(). Wouldn't it be safer to
add those functions before tty_unlock()?

The only output I get from speakup_dummy is:

Speakup
RATE 8
PITCH 8
VOL 8
TONE 8
Dummy found

That's same before and after this ldisc change.

I looked around for tty release code, specifically tty_release() in
drivers/tty/tty_io.c. Not sure if there's something else missing here.
The modules seem to load and unload (multiple times) okay. Kernel log
doesn't show anything odd. I'll still do some more tests and make the
changes you suggested above before sharing the patch.

>
> Samuel

Thanks,
Okash