* [patch 0/1] staging: speakup: flush tty buffers and ensure hardware flow control
@ 2017-05-09 12:40 okash.khawaja
2017-05-09 12:40 ` [patch 1/1] " okash.khawaja
0 siblings, 1 reply; 9+ messages in thread
From: okash.khawaja @ 2017-05-09 12:40 UTC (permalink / raw)
To: Greg Kroah-Hartman, Samuel Thibault, linux-kernel
Cc: William Hubbs, Chris Brannon, Kirk Reiser, speakup, devel
Hi,
This patch applies on top of previous patchset which migrates synths to TTY [1]. It fixes couple of issues and tries to ensure hardware flow control is enabled.
Thanks,
Okash
[1] https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1387738.html
^ permalink raw reply [flat|nested] 9+ messages in thread
* [patch 1/1] staging: speakup: flush tty buffers and ensure hardware flow control
2017-05-09 12:40 [patch 0/1] staging: speakup: flush tty buffers and ensure hardware flow control okash.khawaja
@ 2017-05-09 12:40 ` okash.khawaja
2017-05-10 19:41 ` Alan Cox
0 siblings, 1 reply; 9+ messages in thread
From: okash.khawaja @ 2017-05-09 12:40 UTC (permalink / raw)
To: Greg Kroah-Hartman, Samuel Thibault, linux-kernel
Cc: William Hubbs, Chris Brannon, Kirk Reiser, speakup, devel,
John Covici, Okash Khawaja
[-- Attachment #1: 07_fix_flush --]
[-- Type: text/plain, Size: 5871 bytes --]
This patch fixes the issue where TTY-migrated synths would take a while to shut up after hitting numpad enter key. When calling synth_flush, even though XOFF character is sent as high priority, data buffered in TTY layer is still sent to the synth. This patch flushes that buffered data when synth_flush is called.
It also tries to ensure that hardware flow control is enabled, by setting CRTSCTS using tty's termios.
Reported-by: John Covici <covici@ccs.covici.com>
Signed-off-by: Okash Khawaja <okash.khawaja@gmail.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Index: linux-staging/drivers/staging/speakup/serialio.c
===================================================================
--- linux-staging.orig/drivers/staging/speakup/serialio.c
+++ linux-staging/drivers/staging/speakup/serialio.c
@@ -30,6 +30,7 @@
static void spk_serial_tiocmset(unsigned int set, unsigned int clear);
static unsigned char spk_serial_in(void);
static unsigned char spk_serial_in_nowait(void);
+static void spk_serial_flush_buffer(void);
struct spk_io_ops spk_serial_io_ops = {
.synth_out = spk_serial_out,
@@ -37,6 +38,7 @@
.tiocmset = spk_serial_tiocmset,
.synth_in = spk_serial_in,
.synth_in_nowait = spk_serial_in_nowait,
+ .flush_buffer = spk_serial_flush_buffer,
};
EXPORT_SYMBOL_GPL(spk_serial_io_ops);
@@ -268,6 +270,11 @@
return inb_p(speakup_info.port_tts + UART_RX);
}
+static void spk_serial_flush_buffer(void)
+{
+ /* TODO: flush the UART 16550 buffer */
+}
+
static int spk_serial_out(struct spk_synth *in_synth, const char ch)
{
if (in_synth->alive && spk_wait_for_xmitr(in_synth)) {
Index: linux-staging/drivers/staging/speakup/spk_ttyio.c
===================================================================
--- linux-staging.orig/drivers/staging/speakup/spk_ttyio.c
+++ linux-staging/drivers/staging/speakup/spk_ttyio.c
@@ -85,6 +85,7 @@
static void spk_ttyio_tiocmset(unsigned int set, unsigned int clear);
static unsigned char spk_ttyio_in(void);
static unsigned char spk_ttyio_in_nowait(void);
+static void spk_ttyio_flush_buffer(void);
struct spk_io_ops spk_ttyio_ops = {
.synth_out = spk_ttyio_out,
@@ -92,6 +93,7 @@
.tiocmset = spk_ttyio_tiocmset,
.synth_in = spk_ttyio_in,
.synth_in_nowait = spk_ttyio_in_nowait,
+ .flush_buffer = spk_ttyio_flush_buffer,
};
EXPORT_SYMBOL_GPL(spk_ttyio_ops);
@@ -99,6 +101,7 @@
{
int ret = 0;
struct tty_struct *tty;
+ struct ktermios tmp_termios;
ret = tty_register_ldisc(N_SPEAKUP, &spk_ttyio_ldisc_ops);
if (ret) {
@@ -127,6 +130,18 @@
}
clear_bit(TTY_HUPPED, &tty->flags);
+ /* ensure hardware flow control is enabled */
+ down_read(&tty->termios_rwsem);
+ tmp_termios = tty->termios;
+ up_read(&tty->termios_rwsem);
+
+ if (!(tmp_termios.c_cflag & CRTSCTS)) {
+ tmp_termios.c_cflag |= CRTSCTS;
+ ret = tty_set_termios(tty, &tmp_termios);
+ if (ret)
+ pr_warn("speakup: Failed to set hardware flow control\n");
+ }
+
tty_unlock(tty);
ret = tty_set_ldisc(tty, N_SPEAKUP);
@@ -201,6 +216,11 @@
return (rv == 0xff) ? 0 : rv;
}
+static void spk_ttyio_flush_buffer(void)
+{
+ speakup_tty->ops->flush_buffer(speakup_tty);
+}
+
int spk_ttyio_synth_probe(struct spk_synth *synth)
{
int rv = spk_ttyio_initialise_ldisc(synth->ser);
Index: linux-staging/drivers/staging/speakup/spk_types.h
===================================================================
--- linux-staging.orig/drivers/staging/speakup/spk_types.h
+++ linux-staging/drivers/staging/speakup/spk_types.h
@@ -154,6 +154,7 @@
void (*tiocmset)(unsigned int set, unsigned int clear);
unsigned char (*synth_in)(void);
unsigned char (*synth_in_nowait)(void);
+ void (*flush_buffer)(void);
};
struct spk_synth {
Index: linux-staging/drivers/staging/speakup/speakup_audptr.c
===================================================================
--- linux-staging.orig/drivers/staging/speakup/speakup_audptr.c
+++ linux-staging/drivers/staging/speakup/speakup_audptr.c
@@ -127,6 +127,7 @@
static void synth_flush(struct spk_synth *synth)
{
+ synth->io_ops->flush_buffer();
synth->io_ops->send_xchar(SYNTH_CLEAR);
synth->io_ops->synth_out(synth, PROCSPEECH);
}
Index: linux-staging/drivers/staging/speakup/speakup_decext.c
===================================================================
--- linux-staging.orig/drivers/staging/speakup/speakup_decext.c
+++ linux-staging/drivers/staging/speakup/speakup_decext.c
@@ -221,6 +221,7 @@
static void synth_flush(struct spk_synth *synth)
{
in_escape = 0;
+ synth->io_ops->flush_buffer();
synth->synth_immediate(synth, "\033P;10z\033\\");
}
Index: linux-staging/drivers/staging/speakup/speakup_dectlk.c
===================================================================
--- linux-staging.orig/drivers/staging/speakup/speakup_dectlk.c
+++ linux-staging/drivers/staging/speakup/speakup_dectlk.c
@@ -293,6 +293,7 @@
synth->io_ops->synth_out(synth, ']');
in_escape = 0;
is_flushing = 1;
+ synth->io_ops->flush_buffer();
synth->io_ops->synth_out(synth, SYNTH_CLEAR);
}
Index: linux-staging/drivers/staging/speakup/speakup_spkout.c
===================================================================
--- linux-staging.orig/drivers/staging/speakup/speakup_spkout.c
+++ linux-staging/drivers/staging/speakup/speakup_spkout.c
@@ -125,6 +125,7 @@
static void synth_flush(struct spk_synth *synth)
{
+ synth->io_ops->flush_buffer();
synth->io_ops->send_xchar(SYNTH_CLEAR);
}
Index: linux-staging/drivers/staging/speakup/synth.c
===================================================================
--- linux-staging.orig/drivers/staging/speakup/synth.c
+++ linux-staging/drivers/staging/speakup/synth.c
@@ -120,6 +120,7 @@
void spk_synth_flush(struct spk_synth *synth)
{
+ synth->io_ops->flush_buffer();
synth->io_ops->synth_out(synth, synth->clear);
}
EXPORT_SYMBOL_GPL(spk_synth_flush);
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [patch 1/1] staging: speakup: flush tty buffers and ensure hardware flow control
2017-05-09 12:40 ` [patch 1/1] " okash.khawaja
@ 2017-05-10 19:41 ` Alan Cox
2017-05-11 8:29 ` Okash Khawaja
0 siblings, 1 reply; 9+ messages in thread
From: Alan Cox @ 2017-05-10 19:41 UTC (permalink / raw)
To: okash.khawaja
Cc: Greg Kroah-Hartman, Samuel Thibault, linux-kernel, William Hubbs,
Chris Brannon, Kirk Reiser, speakup, devel, John Covici
> + if (!(tmp_termios.c_cflag & CRTSCTS)) {
> + tmp_termios.c_cflag |= CRTSCTS;
> + ret = tty_set_termios(tty, &tmp_termios);
> + if (ret)
> + pr_warn("speakup: Failed to set hardware flow control\n");
You should check the tty c_cflag after the call rather than rely on an
error code. Strictly speaking tty_set_termios should error if no tty bits
are changed by the request but it never has on Linux. Instead check the
tty gave you the result you wanted.
Alan
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [patch 1/1] staging: speakup: flush tty buffers and ensure hardware flow control
2017-05-10 19:41 ` Alan Cox
@ 2017-05-11 8:29 ` Okash Khawaja
2017-05-11 13:33 ` Alan Cox
0 siblings, 1 reply; 9+ messages in thread
From: Okash Khawaja @ 2017-05-11 8:29 UTC (permalink / raw)
To: Alan Cox
Cc: Greg Kroah-Hartman, Samuel Thibault, linux-kernel, William Hubbs,
Chris Brannon, Kirk Reiser, speakup, devel, John Covici
Hi Alan,
On Wed, May 10, 2017 at 08:41:51PM +0100, Alan Cox wrote:
> > + if (!(tmp_termios.c_cflag & CRTSCTS)) {
> > + tmp_termios.c_cflag |= CRTSCTS;
> > + ret = tty_set_termios(tty, &tmp_termios);
> > + if (ret)
> > + pr_warn("speakup: Failed to set hardware flow control\n");
>
> You should check the tty c_cflag after the call rather than rely on an
> error code. Strictly speaking tty_set_termios should error if no tty bits
> are changed by the request but it never has on Linux. Instead check the
> tty gave you the result you wanted.
Thanks. I will replace the check for return value with check for c_cflag.
May be we should fix this in tty_set_termios?
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [patch 1/1] staging: speakup: flush tty buffers and ensure hardware flow control
2017-05-11 8:29 ` Okash Khawaja
@ 2017-05-11 13:33 ` Alan Cox
2017-05-12 19:35 ` Okash Khawaja
2017-05-12 19:43 ` [patch v2 " Okash Khawaja
0 siblings, 2 replies; 9+ messages in thread
From: Alan Cox @ 2017-05-11 13:33 UTC (permalink / raw)
To: Okash Khawaja
Cc: Greg Kroah-Hartman, Samuel Thibault, linux-kernel, William Hubbs,
Chris Brannon, Kirk Reiser, speakup, devel, John Covici
On Thu, 11 May 2017 09:29:14 +0100
Okash Khawaja <okash.khawaja@gmail.com> wrote:
> Hi Alan,
>
> On Wed, May 10, 2017 at 08:41:51PM +0100, Alan Cox wrote:
> > > + if (!(tmp_termios.c_cflag & CRTSCTS)) {
> > > + tmp_termios.c_cflag |= CRTSCTS;
> > > + ret = tty_set_termios(tty, &tmp_termios);
> > > + if (ret)
> > > + pr_warn("speakup: Failed to set hardware flow control\n");
> >
> > You should check the tty c_cflag after the call rather than rely on an
> > error code. Strictly speaking tty_set_termios should error if no tty bits
> > are changed by the request but it never has on Linux. Instead check the
> > tty gave you the result you wanted.
> Thanks. I will replace the check for return value with check for c_cflag.
>
> May be we should fix this in tty_set_termios?
Possibly. It however changes the external kernel ABI. It's also not a
simple memcmp because any undefined bits must be ignored.
Make a patch, try it and see what breaks ? If nothing breaks then yes it
makes sense IMHO too.
Alan
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [patch 1/1] staging: speakup: flush tty buffers and ensure hardware flow control
2017-05-11 13:33 ` Alan Cox
@ 2017-05-12 19:35 ` Okash Khawaja
2017-05-12 20:18 ` Alan Cox
2017-05-12 19:43 ` [patch v2 " Okash Khawaja
1 sibling, 1 reply; 9+ messages in thread
From: Okash Khawaja @ 2017-05-12 19:35 UTC (permalink / raw)
To: Alan Cox
Cc: Greg Kroah-Hartman, Samuel Thibault, linux-kernel, William Hubbs,
Chris Brannon, Kirk Reiser, speakup, devel, John Covici
On Thu, May 11, 2017 at 02:33:14PM +0100, Alan Cox wrote:
> On Thu, 11 May 2017 09:29:14 +0100
> Okash Khawaja <okash.khawaja@gmail.com> wrote:
>
> > Hi Alan,
> >
> > On Wed, May 10, 2017 at 08:41:51PM +0100, Alan Cox wrote:
> > > > + if (!(tmp_termios.c_cflag & CRTSCTS)) {
> > > > + tmp_termios.c_cflag |= CRTSCTS;
> > > > + ret = tty_set_termios(tty, &tmp_termios);
> > > > + if (ret)
> > > > + pr_warn("speakup: Failed to set hardware flow control\n");
> > >
> > > You should check the tty c_cflag after the call rather than rely on an
> > > error code. Strictly speaking tty_set_termios should error if no tty bits
> > > are changed by the request but it never has on Linux. Instead check the
> > > tty gave you the result you wanted.
> > Thanks. I will replace the check for return value with check for c_cflag.
> >
> > May be we should fix this in tty_set_termios?
>
> Possibly. It however changes the external kernel ABI. It's also not a
> simple memcmp because any undefined bits must be ignored.
>
> Make a patch, try it and see what breaks ? If nothing breaks then yes it
> makes sense IMHO too.
Right, thanks for the heads up. I'll see if I get round to doing it. For
external kernel ABI, will we need to check libc implementations of
termios functions? Will that be sufficient?
Thanks,
Okash
^ permalink raw reply [flat|nested] 9+ messages in thread
* [patch v2 1/1] staging: speakup: flush tty buffers and ensure hardware flow control
2017-05-11 13:33 ` Alan Cox
2017-05-12 19:35 ` Okash Khawaja
@ 2017-05-12 19:43 ` Okash Khawaja
2017-05-15 10:45 ` Greg Kroah-Hartman
1 sibling, 1 reply; 9+ messages in thread
From: Okash Khawaja @ 2017-05-12 19:43 UTC (permalink / raw)
To: Greg Kroah-Hartman, Samuel Thibault, Alan Cox, linux-kernel
Cc: William Hubbs, Chris Brannon, Kirk Reiser, speakup, devel, John Covici
This patch fixes the issue where TTY-migrated synths would take a while to shut up after hitting numpad enter key. When calling synth_flush, even though XOFF character is sent as high priority, data buffered in TTY layer is still sent to the synth. This patch flushes that buffered data when synth_flush is called.
It also tries to ensure that hardware flow control is enabled, by setting CRTSCTS using tty's termios.
Reported-by: John Covici <covici@ccs.covici.com>
Signed-off-by: Okash Khawaja <okash.khawaja@gmail.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Index: linux-staging/drivers/staging/speakup/serialio.c
===================================================================
--- linux-staging.orig/drivers/staging/speakup/serialio.c
+++ linux-staging/drivers/staging/speakup/serialio.c
@@ -30,6 +30,7 @@
static void spk_serial_tiocmset(unsigned int set, unsigned int clear);
static unsigned char spk_serial_in(void);
static unsigned char spk_serial_in_nowait(void);
+static void spk_serial_flush_buffer(void);
struct spk_io_ops spk_serial_io_ops = {
.synth_out = spk_serial_out,
@@ -37,6 +38,7 @@
.tiocmset = spk_serial_tiocmset,
.synth_in = spk_serial_in,
.synth_in_nowait = spk_serial_in_nowait,
+ .flush_buffer = spk_serial_flush_buffer,
};
EXPORT_SYMBOL_GPL(spk_serial_io_ops);
@@ -268,6 +270,11 @@
return inb_p(speakup_info.port_tts + UART_RX);
}
+static void spk_serial_flush_buffer(void)
+{
+ /* TODO: flush the UART 16550 buffer */
+}
+
static int spk_serial_out(struct spk_synth *in_synth, const char ch)
{
if (in_synth->alive && spk_wait_for_xmitr(in_synth)) {
Index: linux-staging/drivers/staging/speakup/spk_ttyio.c
===================================================================
--- linux-staging.orig/drivers/staging/speakup/spk_ttyio.c
+++ linux-staging/drivers/staging/speakup/spk_ttyio.c
@@ -85,6 +85,7 @@
static void spk_ttyio_tiocmset(unsigned int set, unsigned int clear);
static unsigned char spk_ttyio_in(void);
static unsigned char spk_ttyio_in_nowait(void);
+static void spk_ttyio_flush_buffer(void);
struct spk_io_ops spk_ttyio_ops = {
.synth_out = spk_ttyio_out,
@@ -92,13 +93,22 @@
.tiocmset = spk_ttyio_tiocmset,
.synth_in = spk_ttyio_in,
.synth_in_nowait = spk_ttyio_in_nowait,
+ .flush_buffer = spk_ttyio_flush_buffer,
};
EXPORT_SYMBOL_GPL(spk_ttyio_ops);
+static inline void get_termios(struct tty_struct *tty, struct ktermios *out_termios)
+{
+ down_read(&tty->termios_rwsem);
+ *out_termios = tty->termios;
+ up_read(&tty->termios_rwsem);
+}
+
static int spk_ttyio_initialise_ldisc(int ser)
{
int ret = 0;
struct tty_struct *tty;
+ struct ktermios tmp_termios;
ret = tty_register_ldisc(N_SPEAKUP, &spk_ttyio_ldisc_ops);
if (ret) {
@@ -127,6 +137,20 @@
}
clear_bit(TTY_HUPPED, &tty->flags);
+ /* ensure hardware flow control is enabled */
+ get_termios(tty, &tmp_termios);
+ if (!(tmp_termios.c_cflag & CRTSCTS)) {
+ tmp_termios.c_cflag |= CRTSCTS;
+ tty_set_termios(tty, &tmp_termios);
+ /*
+ * check c_cflag to see if it's updated as tty_set_termios may not return
+ * error even when no tty bits are changed by the request.
+ */
+ get_termios(tty, &tmp_termios);
+ if (!(tmp_termios.c_cflag & CRTSCTS))
+ pr_warn("speakup: Failed to set hardware flow control\n");
+ }
+
tty_unlock(tty);
ret = tty_set_ldisc(tty, N_SPEAKUP);
@@ -201,6 +225,11 @@
return (rv == 0xff) ? 0 : rv;
}
+static void spk_ttyio_flush_buffer(void)
+{
+ speakup_tty->ops->flush_buffer(speakup_tty);
+}
+
int spk_ttyio_synth_probe(struct spk_synth *synth)
{
int rv = spk_ttyio_initialise_ldisc(synth->ser);
Index: linux-staging/drivers/staging/speakup/spk_types.h
===================================================================
--- linux-staging.orig/drivers/staging/speakup/spk_types.h
+++ linux-staging/drivers/staging/speakup/spk_types.h
@@ -154,6 +154,7 @@
void (*tiocmset)(unsigned int set, unsigned int clear);
unsigned char (*synth_in)(void);
unsigned char (*synth_in_nowait)(void);
+ void (*flush_buffer)(void);
};
struct spk_synth {
Index: linux-staging/drivers/staging/speakup/speakup_audptr.c
===================================================================
--- linux-staging.orig/drivers/staging/speakup/speakup_audptr.c
+++ linux-staging/drivers/staging/speakup/speakup_audptr.c
@@ -127,6 +127,7 @@
static void synth_flush(struct spk_synth *synth)
{
+ synth->io_ops->flush_buffer();
synth->io_ops->send_xchar(SYNTH_CLEAR);
synth->io_ops->synth_out(synth, PROCSPEECH);
}
Index: linux-staging/drivers/staging/speakup/speakup_decext.c
===================================================================
--- linux-staging.orig/drivers/staging/speakup/speakup_decext.c
+++ linux-staging/drivers/staging/speakup/speakup_decext.c
@@ -221,6 +221,7 @@
static void synth_flush(struct spk_synth *synth)
{
in_escape = 0;
+ synth->io_ops->flush_buffer();
synth->synth_immediate(synth, "\033P;10z\033\\");
}
Index: linux-staging/drivers/staging/speakup/speakup_dectlk.c
===================================================================
--- linux-staging.orig/drivers/staging/speakup/speakup_dectlk.c
+++ linux-staging/drivers/staging/speakup/speakup_dectlk.c
@@ -293,6 +293,7 @@
synth->io_ops->synth_out(synth, ']');
in_escape = 0;
is_flushing = 1;
+ synth->io_ops->flush_buffer();
synth->io_ops->synth_out(synth, SYNTH_CLEAR);
}
Index: linux-staging/drivers/staging/speakup/speakup_spkout.c
===================================================================
--- linux-staging.orig/drivers/staging/speakup/speakup_spkout.c
+++ linux-staging/drivers/staging/speakup/speakup_spkout.c
@@ -125,6 +125,7 @@
static void synth_flush(struct spk_synth *synth)
{
+ synth->io_ops->flush_buffer();
synth->io_ops->send_xchar(SYNTH_CLEAR);
}
Index: linux-staging/drivers/staging/speakup/synth.c
===================================================================
--- linux-staging.orig/drivers/staging/speakup/synth.c
+++ linux-staging/drivers/staging/speakup/synth.c
@@ -120,6 +120,7 @@
void spk_synth_flush(struct spk_synth *synth)
{
+ synth->io_ops->flush_buffer();
synth->io_ops->synth_out(synth, synth->clear);
}
EXPORT_SYMBOL_GPL(spk_synth_flush);
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [patch 1/1] staging: speakup: flush tty buffers and ensure hardware flow control
2017-05-12 19:35 ` Okash Khawaja
@ 2017-05-12 20:18 ` Alan Cox
0 siblings, 0 replies; 9+ messages in thread
From: Alan Cox @ 2017-05-12 20:18 UTC (permalink / raw)
To: Okash Khawaja
Cc: Greg Kroah-Hartman, Samuel Thibault, linux-kernel, William Hubbs,
Chris Brannon, Kirk Reiser, speakup, devel, John Covici
On Fri, 12 May 2017 20:35:18 +0100
Okash Khawaja <okash.khawaja@gmail.com> wrote:
> On Thu, May 11, 2017 at 02:33:14PM +0100, Alan Cox wrote:
> > On Thu, 11 May 2017 09:29:14 +0100
> > Okash Khawaja <okash.khawaja@gmail.com> wrote:
> >
> > > Hi Alan,
> > >
> > > On Wed, May 10, 2017 at 08:41:51PM +0100, Alan Cox wrote:
> > > > > + if (!(tmp_termios.c_cflag & CRTSCTS)) {
> > > > > + tmp_termios.c_cflag |= CRTSCTS;
> > > > > + ret = tty_set_termios(tty, &tmp_termios);
> > > > > + if (ret)
> > > > > + pr_warn("speakup: Failed to set hardware flow control\n");
> > > >
> > > > You should check the tty c_cflag after the call rather than rely on an
> > > > error code. Strictly speaking tty_set_termios should error if no tty bits
> > > > are changed by the request but it never has on Linux. Instead check the
> > > > tty gave you the result you wanted.
> > > Thanks. I will replace the check for return value with check for c_cflag.
> > >
> > > May be we should fix this in tty_set_termios?
> >
> > Possibly. It however changes the external kernel ABI. It's also not a
> > simple memcmp because any undefined bits must be ignored.
> >
> > Make a patch, try it and see what breaks ? If nothing breaks then yes it
> > makes sense IMHO too.
>
> Right, thanks for the heads up. I'll see if I get round to doing it. For
> external kernel ABI, will we need to check libc implementations of
> termios functions? Will that be sufficient?
I think the only way you find out is to try it and run a distro like
that. If it seems ok submit the patch to linux-next with a clear note it
potentially changes the ABI so if people find bugs it can be reverted.
Alan
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [patch v2 1/1] staging: speakup: flush tty buffers and ensure hardware flow control
2017-05-12 19:43 ` [patch v2 " Okash Khawaja
@ 2017-05-15 10:45 ` Greg Kroah-Hartman
0 siblings, 0 replies; 9+ messages in thread
From: Greg Kroah-Hartman @ 2017-05-15 10:45 UTC (permalink / raw)
To: Okash Khawaja
Cc: Samuel Thibault, Alan Cox, linux-kernel, devel, Kirk Reiser,
speakup, John Covici, Chris Brannon
On Fri, May 12, 2017 at 08:43:58PM +0100, Okash Khawaja wrote:
> This patch fixes the issue where TTY-migrated synths would take a while
> to shut up after hitting numpad enter key. When calling synth_flush,
> even though XOFF character is sent as high priority, data buffered in
> TTY layer is still sent to the synth. This patch flushes that buffered
> data when synth_flush is called.
>
> It also tries to ensure that hardware flow control is enabled, by
> setting CRTSCTS using tty's termios.
>
> Reported-by: John Covici <covici@ccs.covici.com>
> Signed-off-by: Okash Khawaja <okash.khawaja@gmail.com>
> Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Doesn't apply as I didn't take your full series. Please resend it with
that series fixed up.
thanks,
greg k-h
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2017-05-15 10:46 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-05-09 12:40 [patch 0/1] staging: speakup: flush tty buffers and ensure hardware flow control okash.khawaja
2017-05-09 12:40 ` [patch 1/1] " okash.khawaja
2017-05-10 19:41 ` Alan Cox
2017-05-11 8:29 ` Okash Khawaja
2017-05-11 13:33 ` Alan Cox
2017-05-12 19:35 ` Okash Khawaja
2017-05-12 20:18 ` Alan Cox
2017-05-12 19:43 ` [patch v2 " Okash Khawaja
2017-05-15 10:45 ` Greg Kroah-Hartman
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