[U-Boot] [PATCH 1/2] serial: mxc: support DTE mode

[Ryan Harkin]

Hi Stefan,

Thanks for looking so quickly.

On 19 January 2018 at 12:23, Stefan Agner <stefan.agner at toradex.com> wrote:

> Hi Ryan,
>
>
> On 19.01.2018 10:53, Ryan Harkin wrote:
> > Add DTE mode support via Kconfig on the MXC uart.
>
> Make use of the driver model, there DTE is supported already today:
> https://lists.denx.de/pipermail/u-boot/2016-July/259573.html


My change would be useful for other non-DM users of serial_mxc.c, of
course. Not just WaRP7.

I don't have any objection to WaRP7 moving to DM, although that isn't my
call, but moving using the driver model is not a straight-forward change,
is it? WaRP7 today doesn't use it.

Do you have an example of a board using this driver that switched using the
driver model? I'd like to see the scale of the changes needed.

Regards,
Ryan.



>
> --
> Stefan
>
> >
> > Signed-off-by: Ryan Harkin <ryan.harkin at linaro.org>
> > Reviewed-by: Bryan O'Donoghue <bryan.odonoghue at linaro.org>
> > ---
> >  drivers/serial/Kconfig      |  7 +++++++
> >  drivers/serial/serial_mxc.c | 10 ++++++++--
> >  2 files changed, 15 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
> > index 122b8e7..0df57c0 100644
> > --- a/drivers/serial/Kconfig
> > +++ b/drivers/serial/Kconfig
> > @@ -597,4 +597,11 @@ config SYS_SDMR
> >       depends on MPC8XX_CONS
> >       default 0
> >
> > +config SERIAL_MXC_DTE_MODE
> > +     bool "Use DTE mode for the MXC UART"
> > +     default n
> > +     help
> > +       This is used to set DTE mode on the serial console controlled by
> > +       serial_mxc.c.
> > +
> >  endmenu
> > diff --git a/drivers/serial/serial_mxc.c b/drivers/serial/serial_mxc.c
> > index cce80a8..e7ea30c 100644
> > --- a/drivers/serial/serial_mxc.c
> > +++ b/drivers/serial/serial_mxc.c
> > @@ -111,6 +111,12 @@
> >  #define TXTL         2  /* reset default */
> >  #define RXTL         1  /* reset default */
> >
> > +#ifdef CONFIG_SERIAL_MXC_DTE_MODE
> > +#define MXC_DTE_MODE true
> > +#else
> > +#define MXC_DTE_MODE false
> > +#endif
> > +
> >  DECLARE_GLOBAL_DATA_PTR;
> >
> >  struct mxc_uart {
> > @@ -189,7 +195,7 @@ static void mxc_serial_setbrg(void)
> >       if (!gd->baudrate)
> >               gd->baudrate = CONFIG_BAUDRATE;
> >
> > -     _mxc_serial_setbrg(mxc_base, clk, gd->baudrate, false);
> > +     _mxc_serial_setbrg(mxc_base, clk, gd->baudrate, MXC_DTE_MODE);
> >  }
> >
> >  static int mxc_serial_getc(void)
> > @@ -367,7 +373,7 @@ static inline void _debug_uart_init(void)
> >
> >       _mxc_serial_init(base);
> >       _mxc_serial_setbrg(base, CONFIG_DEBUG_UART_CLOCK,
> > -                        CONFIG_BAUDRATE, false);
> > +                        CONFIG_BAUDRATE, MXC_DTE_MODE);
> >  }
> >
> >  static inline void _debug_uart_putc(int ch)
>
>