Re: [PATCH 1/3] serial: atmel: Don't check for mctrl_gpio_to_gpiod() returning error

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi Uwe,

On Wed, Aug 14, 2019 at 11:36 AM Uwe Kleine-König
<u.kleine-koenig@xxxxxxxxxxxxxx> wrote:
> On Wed, Aug 14, 2019 at 11:29:22AM +0200, Geert Uytterhoeven wrote:
> > Since commit 1d267ea6539f2663 ("serial: mctrl-gpio: simplify init
> > routine"), mctrl_gpio_init() returns failure if the assignment to any
> > member of the gpio array results in an error pointer.
> > Since commit c359522194593815 ("serial: mctrl_gpio: Avoid probe failures
> > in case of missing gpiolib"), mctrl_gpio_to_gpiod() returns NULL in the
> > !CONFIG_GPIOLIB case.
> > Hence there is no longer a need to check for mctrl_gpio_to_gpiod()
> > returning an error value.  A simple NULL check is sufficient.
> >
> > This follows the spirit of commit 445df7ff3fd1a0a9 ("serial: mctrl-gpio:
> > drop usages of IS_ERR_OR_NULL") in the mctrl-gpio core.
> >
> > Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> > ---
> >  drivers/tty/serial/atmel_serial.c | 12 ++++--------
> >  1 file changed, 4 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
> > index 19a85d6fe3d20541..e9620a81166b7dc1 100644
> > --- a/drivers/tty/serial/atmel_serial.c
> > +++ b/drivers/tty/serial/atmel_serial.c
> > @@ -303,32 +303,28 @@ static unsigned int atmel_get_lines_status(struct uart_port *port)
> >
> >       mctrl_gpio_get(atmel_port->gpios, &ret);
> >
> > -     if (!IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(atmel_port->gpios,
> > -                                             UART_GPIO_CTS))) {
> > +     if (mctrl_gpio_to_gpiod(atmel_port->gpios, UART_GPIO_CTS)) {
> >               if (ret & TIOCM_CTS)
> >                       status &= ~ATMEL_US_CTS;
> >               else
> >                       status |= ATMEL_US_CTS;
> >       }
>
> The change is fine, but it seems the atmel driver doesn't use mctrl_gpio
> as expected (at least as expected by me). IMHO driving the hardware
> function of the CTS pin shouldn't be conditional on the presence of a
> cts-gpio. Is there a reason not to just drop the if completely?

The above code returns the hardware status if CTS is not a GPIO, and
returns (overrides with) the GPIO status if CTS is a GPIO.
Isn't that correct, or am I missing something?

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds



[Index of Archives]     [Kernel Newbies]     [Security]     [Netfilter]     [Bugtraq]     [Linux PPP]     [Linux FS]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Samba]     [Video 4 Linux]     [Linmodem]     [Device Mapper]     [Linux Kernel for ARM]

  Powered by Linux