Re: [PATCH] [RFC] i2c: imx: make use of format specifier %dE

[Oleksij Rempel]

On 29.08.19 22:39, Wolfram Sang wrote:
> On Thu, Aug 29, 2019 at 06:29:05AM +0200, Uwe Kleine-KÃnig wrote:
> > I created a patch that teaches printk et al to emit a symbolic error
> > name for an error valued integer[1]. With that applied
> >
> > 	dev_err(&pdev->dev, "can't enable I2C clock, ret=%dE\n", ret);
> >
> > emits
> >
> > 	... can't enable I2C clock, ret=EIO
> >
> > if ret is -EIO. Petr Mladek (i.e. one of the printk maintainers) had
> > concerns if this would be well received and worth the effort. He asked
> > to present it to a few subsystems. So for now, this patch converting the
> > i2c-imx driver shouldn't be applied yet but it would be great to get
> > some feedback about if you think that being able to easily printk (for
> > example) "EIO" instead of "-5" is a good idea. Would it help you? Do you
> > think it helps your users?
>
> Yes, it would help me. And users, too, I am quite sure. For me, if I mix
> up two numbers while debugging, I am hunting ghosts for a while until I
> realize my mistake. So:
>
> Acked-by: Wolfram Sang <wsa@xxxxxxxxxxxxx>
>
> I think the main drawback is that ERRORCODES in vsprintf.c now need
> maintenance, but I think it is worth the effort. I'd be interested in
> the overhead in size this causes, but I also think it is worth the
> effort. (It could even be compiled out if we have some generic Kconfig
> symbol for smaller kernels).


I like it, at least it will safe me some time.
I tested this patch together with the vprintf patch, so result looks like:
[    0.281843] imx-i2c 21a0000.i2c: can't enable I2C clock, ret=EIO
[    0.281891] imx-i2c: probe of 21a0000.i2c failed with error -5

Tested-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>

Kind regards,
Oleksij Rempel

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