[PATCH] serial: mxs-auart: support CMSPAR termios cflag

[PATCH] serial: mxs-auart: support CMSPAR termios cflag

[Stefan Wahren]

Hi Wolfgang,

> --- a/drivers/tty/serial/mxs-auart.c
> +++ b/drivers/tty/serial/mxs-auart.c
> @@ -95,6 +95,7 @@
>  #define AUART_LINECTRL_BAUD_DIVFRAC_SHIFT	8
>  #define AUART_LINECTRL_BAUD_DIVFRAC_MASK	0x00003f00
>  #define AUART_LINECTRL_BAUD_DIVFRAC(v)		(((v) & 0x3f) << 8)
> +#define AUART_LINECTRL_SPS			(1 << 7)
>  #define AUART_LINECTRL_WLEN_MASK		0x00000060
>  #define AUART_LINECTRL_WLEN(v)			(((v) & 0x3) << 5)
>  #define AUART_LINECTRL_FEN			(1 << 4)
> @@ -1010,10 +1011,12 @@ static void mxs_auart_settermios(struct uart_port *u,
> 	ctrl |= AUART_LINECTRL_WLEN(bm);
> 
> 	/* parity */
> -	if (cflag & PARENB) {
> +	if (cflag & (PARENB|CMSPAR)) {

does it make sense to enable stick parity in case parity is disabled?

The i.MX28 reference manual doesn't describe this case explicit.

Stefan

[PATCH] serial: mxs-auart: support CMSPAR termios cflag

[Wolfgang Ocker]

On Tue, 2016-12-06 at 14:36 +0100, Stefan Wahren wrote:
> Hi Wolfgang,
> 
> > --- a/drivers/tty/serial/mxs-auart.c
> > +++ b/drivers/tty/serial/mxs-auart.c
> > @@ -95,6 +95,7 @@
> > ?#define AUART_LINECTRL_BAUD_DIVFRAC_SHIFT	8
> > ?#define AUART_LINECTRL_BAUD_DIVFRAC_MASK	0x00003f00
> > ?#define AUART_LINECTRL_BAUD_DIVFRAC(v)		(((v) & 0x3f) << 8)
> > +#define AUART_LINECTRL_SPS			(1 << 7)
> > ?#define AUART_LINECTRL_WLEN_MASK		0x00000060
> > ?#define AUART_LINECTRL_WLEN(v)			(((v) & 0x3) << 5)
> > ?#define AUART_LINECTRL_FEN			(1 << 4)
> > @@ -1010,10 +1011,12 @@ static void mxs_auart_settermios(struct uart_port
> > *u,
> > 	ctrl |= AUART_LINECTRL_WLEN(bm);
> > 
> > 	/* parity */
> > -	if (cflag & PARENB) {
> > +	if (cflag & (PARENB|CMSPAR)) {
> 
> does it make sense to enable stick parity in case parity is disabled?
> 
> The i.MX28 reference manual doesn't describe this case explicit.

Thanks Stefan for the hint. I think it's okay on the hardware side since the
PEN bit is always set and therefore it can not happen that SPS is set but not
PEN.

But on the termios side it makes sense to require PARENB to be set in c_cflag
if CMSPAR is requested.

So I will provide an updated patch soon.

Wolfgang

[PATCH] serial: mxs-auart: support CMSPAR termios cflag

[Wolfgang Ocker]

If CMSPAR is set in the c_cflag of termios, "stick" parity is enabled.

Tested on an i.MX28 system

Signed-off-by: Wolfgang Ocker <weo@reccoware.de>
---
v2: require PARENB to be also set in termios' c_cflag for CMSPAR
---
 drivers/tty/serial/mxs-auart.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c
index 770454e0dfa3..fd819ea26762 100644
--- a/drivers/tty/serial/mxs-auart.c
+++ b/drivers/tty/serial/mxs-auart.c
@@ -95,6 +95,7 @@
 #define AUART_LINECTRL_BAUD_DIVFRAC_SHIFT	8
 #define AUART_LINECTRL_BAUD_DIVFRAC_MASK	0x00003f00
 #define AUART_LINECTRL_BAUD_DIVFRAC(v)		(((v) & 0x3f) << 8)
+#define AUART_LINECTRL_SPS			(1 << 7)
 #define AUART_LINECTRL_WLEN_MASK		0x00000060
 #define AUART_LINECTRL_WLEN(v)			(((v) & 0x3) << 5)
 #define AUART_LINECTRL_FEN			(1 << 4)
@@ -1014,6 +1015,8 @@ static void mxs_auart_settermios(struct uart_port *u,
 		ctrl |= AUART_LINECTRL_PEN;
 		if ((cflag & PARODD) == 0)
 			ctrl |= AUART_LINECTRL_EPS;
+		if (cflag & CMSPAR)
+			ctrl |= AUART_LINECTRL_SPS;
 	}
 
 	u->read_status_mask = 0;
-- 
2.10.0

[PATCH] serial: mxs-auart: support CMSPAR termios cflag

[Stefan Wahren]

Hi Wolfgang,

> If CMSPAR is set in the c_cflag of termios, "stick" parity is enabled.

you can have my

Acked-by: Stefan Wahren <stefan.wahren@i2se.com>

for this version 2 from 12.12.2016.

But in order to increase the chance that your patch get merged, please
resend your patch:
* with the correct version in your subject line
* not during the merge window
* with my Acked-by
* with a copy to linux-serial at vger.kernel.org

Thanks
Stefan

[PATCH] serial: mxs-auart: support CMSPAR termios cflag

[Wolfgang Ocker]

If CMSPAR is set in the c_cflag of termios, "stick" parity is enabled.

Tested on an i.MX28 system

Signed-off-by: Wolfgang Ocker <weo@reccoware.de>
---
 drivers/tty/serial/mxs-auart.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c
index 770454e0dfa3..9d344f734d44 100644
--- a/drivers/tty/serial/mxs-auart.c
+++ b/drivers/tty/serial/mxs-auart.c
@@ -95,6 +95,7 @@
 #define AUART_LINECTRL_BAUD_DIVFRAC_SHIFT	8
 #define AUART_LINECTRL_BAUD_DIVFRAC_MASK	0x00003f00
 #define AUART_LINECTRL_BAUD_DIVFRAC(v)		(((v) & 0x3f) << 8)
+#define AUART_LINECTRL_SPS			(1 << 7)
 #define AUART_LINECTRL_WLEN_MASK		0x00000060
 #define AUART_LINECTRL_WLEN(v)			(((v) & 0x3) << 5)
 #define AUART_LINECTRL_FEN			(1 << 4)
@@ -1010,10 +1011,12 @@ static void mxs_auart_settermios(struct uart_port *u,
 	ctrl |= AUART_LINECTRL_WLEN(bm);
 
 	/* parity */
-	if (cflag & PARENB) {
+	if (cflag & (PARENB|CMSPAR)) {
 		ctrl |= AUART_LINECTRL_PEN;
 		if ((cflag & PARODD) == 0)
 			ctrl |= AUART_LINECTRL_EPS;
+		if (cflag & CMSPAR)
+			ctrl |= AUART_LINECTRL_SPS;
 	}
 
 	u->read_status_mask = 0;
-- 
2.10.0