Hi Linus,
On Mon, May 2, 2016 at 11:25 AM, Linus Walleij <linus.wall...@linaro.org> wrote:
> On Mon, May 2, 2016 at 11:10 AM, Geert Uytterhoeven
> <ge...@linux-m68k.org> wrote:
>> On Mon, May 2, 2016 at 11:06 AM, Linus Walleij <linus.wall...@linaro.org>
>> wrote:
>>> On Mon, May 2, 2016 at 11:04 AM, Geert Uytterhoeven
>>> <ge...@linux-m68k.org> wrote:
>>>
>>>> [silly response deleted]
>>>>
>>>> Scrap it.
>>>
>>> :D
>>>
>>>> The only annoying thing is that 0 cannot easily be propagated upstream as
>>>> an error code, so it has to be tested for explicitly.
>>>
>>> Well with the Big Penguin's clear opinion on the matter there is not
>>> much we can do.
>>>
>>> What about this?
>>>
>>> diff --git a/drivers/tty/serial/serial_mctrl_gpio.c
>>> b/drivers/tty/serial/serial_mctrl_gpio.c
>>> index 02147361eaa9..2297ec781681 100644
>>> --- a/drivers/tty/serial/serial_mctrl_gpio.c
>>> +++ b/drivers/tty/serial/serial_mctrl_gpio.c
>>> @@ -172,6 +172,13 @@ struct mctrl_gpios *mctrl_gpio_init(struct
>>> uart_port *port, unsigned int idx)
>>> dev_err(port->dev,
>>> "failed to find corresponding irq for
>>> %s (idx=%d, err=%d)\n",
>>> mctrl_gpios_desc[i].name, idx, ret);
>>> + /*
>>> + * Satisfy the error code semantics for a missing
>>> IRQ,
>>> + * 0 means NO_IRQ, but the framework needs to return
>>> + * a negative to deal with the error.
>>> + */
>>> + if (!ret)
>>> + ret = -ENOSYS;
>>
>> No, not -ENOSYS, as that triggers my initial problem again (please read the
>> deleted silly response ;-)
>> Checkpatch says: "ENOSYS means 'invalid syscall nr' and nothing else".
>>
>> -EINVAL?
Upon reconsideration, -ENXIO.
> Sure, whatever works with your semantics.
>
> Will you test & send a patch?
This works fine, but I'm a bit reluctant to send out the patches...
gpiod_to_irq() is documented to return a negative error code on failure,
cfr. Documentation/gpio/consumer.txt and drivers/gpio/gpiolib.c.
In fact the check in mctrl_gpio_init() is the only caller that
considers zero as an
error.
Perhaps gpiod_to_irq() should handle .to_irq() returning zero instead?
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@linux-m68k.org
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
