lkml.org 
[lkml]   [2020]   [Sep]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v13 2/2] Add PWM fan controller driver for LGM SoC
On Thu, Sep 24, 2020 at 04:23:34PM +0300, Andy Shevchenko wrote:
> On Thu, Sep 24, 2020 at 08:55:34AM +0200, Uwe Kleine-König wrote:
> > On Tue, Sep 15, 2020 at 04:23:37PM +0800, Rahul Tanwar wrote:
>
> ...
>
> > > + ret = lgm_clk_enable(dev, pc);
> > > + if (ret) {
> > > + dev_err(dev, "failed to enable clock\n");
> >
> > You used dev_err_probe four times for six error paths. I wonder why you
> > didn't use it here (and below for a failing pwmchip_add()).
>
> dev_err_probe() makes sense when we might experience deferred probe. In neither
> of mentioned function this can be the case.
>
> > > + return ret;
> > > + }
>
> ...
>
> > > + ret = lgm_reset_control_deassert(dev, pc);
> > > + if (ret)
> > > + return dev_err_probe(dev, ret, "cannot deassert reset control\n");
> >
> > After lgm_reset_control_deassert is called pc->rst is unused. So there
> > is no need to have this member in struct lgm_pwm_chip. The same applies
> > to ->clk. (You have to pass rst (or clk) to devm_add_action_or_reset for
> > that to work. Looks like a nice idea anyhow.)
>
> True. And above dev_err_probe() is not needed.

You argue that dev_err_probe() gives no benefit as
lgm_reset_control_deassert won't return -EPROBE_DEFER, right?

Still I consider it a useful function because

a) I (as an author or as a reviewer) don't need to think if the
failing function might return -EPROBE_DEFER now or in the future.
dev_err_probe does the right thing even for functions that don't
return -EPROBE_DEFER.

b) With dev_err_probe() I can accomplish things in a single line that
need two lines when open coding it.

c) dev_err_probe() emits the symbolic error name without having to
resort to %pe + ERR_PTR.

d) Using dev_err_probe() for all error paths gives a consistency that I
like with a maintainer's hat on.

So I still want to request using dev_err_probe() in all error paths.

Best regards
Uwe

--
Pengutronix e.K. | Uwe Kleine-König |
Industrial Linux Solutions | https://www.pengutronix.de/ |
[unhandled content-type:application/pgp-signature]
\
 
 \ /
  Last update: 2020-09-24 16:18    [W:0.110 / U:1.512 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site