[U-Boot] [PATCH] dm: serial: Move a carriage return before a line feed

[Bin Meng]

Hi Alison,

On Wed, Feb 24, 2016 at 3:35 PM, Huan Wang <alison.wang at nxp.com> wrote:
> Hi, Bin,
>
>> On Wed, Feb 24, 2016 at 11:56 AM, Alison Wang <b18965 at freescale.com>
>> wrote:
>> > In general, a carriage return needs to execute before a line feed.
>> > The patch is to change serial DM driver based on this rule.
>> >
>> > Signed-off-by: Alison Wang <alison.wang at nxp.com>
>> > ---
>> >  drivers/serial/serial-uclass.c | 5 +++--
>> >  1 file changed, 3 insertions(+), 2 deletions(-)
>> >
>> > diff --git a/drivers/serial/serial-uclass.c
>> > b/drivers/serial/serial-uclass.c index 1c447ff..f154eb1 100644
>> > --- a/drivers/serial/serial-uclass.c
>> > +++ b/drivers/serial/serial-uclass.c
>> > @@ -123,11 +123,12 @@ static void _serial_putc(struct udevice *dev,
>> char ch)
>> >         struct dm_serial_ops *ops = serial_get_ops(dev);
>> >         int err;
>> >
>> > +       if (ch == '\n')
>> > +               _serial_putc(dev, '\r');
>> > +
>> >         do {
>> >                 err = ops->putc(dev, ch);
>> >         } while (err == -EAGAIN);
>> > -       if (ch == '\n')
>> > -               _serial_putc(dev, '\r');
>> >  }
>> >
>>
>> We should also clean up all DM serial driver to remove this handling in
>> their driver. eg: serial_lpuart.c/serial_mxc.c
>>
> [Alison Wang] Thanks for your advice. Yes, I agree. This handling in
> particular driver is redundant.
>
> It seems only serial_lpuart.c and serial_arc.c has this handling. For
> serial_mxc.c, this handling is only in the non-DM .putc function,
> but not in the DM .putc function. Do you think it is necessary to change
> the non-DM .putc function?
>

No, we should keep the non-DM putc function as it is now. But this
serial_mxc.c, its non-DM putc version has the same issue as the
serial-uclass.c, so it should be fixed. The legacy serial_pxa.c,
serial_s3c24x0.c and usbtty.c also have the same problem.

Regards,
Bin