Re: [PATCH] platform/x86: fujitsu-laptop: rework logolamp_set() to properly handle errors

From: MichaÅ KÄpieÅ
Date: Fri Jan 06 2017 - 14:24:47 EST


> On Thu, Jan 5, 2017 at 3:11 PM, MichaÅ KÄpieÅ <kernel@xxxxxxxxxx> wrote:
> > Potential errors returned by some call_fext_func() calls inside
> > logolamp_set() are currently ignored. Rework logolamp_set() to properly
> > handle them. This causes one more call_fext_func() call to be made in
> > the LED_OFF case, though one could argue that this is logically the
> > right thing to do (even though the extra call is not needed to shut the
> > LED off).
> >
> > Signed-off-by: MichaÅ KÄpieÅ <kernel@xxxxxxxxxx>
> > ---
> > This is a follow-up to a recent patch, "platform/x86: fujitsu-laptop:
> > use brightness_set_blocking for LED-setting callbacks" and thus needs
> > the latter to be applied first (currently it is already applied in
> > testing).
> >
> > Instead of sticking "if (ret < 0) return ret;" in two branches I decided
> > to restructure logolamp_set() for improved clarity and also to make it
> > resemble logolamp_get() a bit more.
> >
> > drivers/platform/x86/fujitsu-laptop.c | 20 ++++++++++++--------
> > 1 file changed, 12 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/platform/x86/fujitsu-laptop.c b/drivers/platform/x86/fujitsu-laptop.c
> > index b725a907a91f..12f7a8346dd0 100644
> > --- a/drivers/platform/x86/fujitsu-laptop.c
> > +++ b/drivers/platform/x86/fujitsu-laptop.c
> > @@ -271,15 +271,19 @@ static int call_fext_func(int cmd, int arg0, int arg1, int arg2)
> > static int logolamp_set(struct led_classdev *cdev,
> > enum led_brightness brightness)
> > {
> > - if (brightness >= LED_FULL) {
> > - call_fext_func(FUNC_LEDS, 0x1, LOGOLAMP_POWERON, FUNC_LED_ON);
> > - return call_fext_func(FUNC_LEDS, 0x1, LOGOLAMP_ALWAYS, FUNC_LED_ON);
> > - } else if (brightness >= LED_HALF) {
> > - call_fext_func(FUNC_LEDS, 0x1, LOGOLAMP_POWERON, FUNC_LED_ON);
> > - return call_fext_func(FUNC_LEDS, 0x1, LOGOLAMP_ALWAYS, FUNC_LED_OFF);
> > - } else {
> > - return call_fext_func(FUNC_LEDS, 0x1, LOGOLAMP_POWERON, FUNC_LED_OFF);
>
> > + int ret, poweron = FUNC_LED_OFF, always = FUNC_LED_OFF;
> > +
> > + if (brightness >= LED_HALF) {
> > + poweron = FUNC_LED_ON;
> > + if (brightness >= LED_FULL)
> > + always = FUNC_LED_ON;
> > }
>
> But if you set ON by default the above could be written like
>
> if (brightness < LED_FULL)
> always = FUNC_LED_OFF;
>
> if (brightness < LED_HALF)
> poweron = FUNC_LED_OFF;

Ah, neat, thanks. Jonathan, assuming you also like this, I will later
submit v2 using this approach.

--
Best regards,
MichaÅ KÄpieÅ