On Wed, 31 Jul 2013, Kim, Milo wrote:
> Thanks for the review, please see my comments.
>
> > <snip> * looks good up to me up to here *
> >
> > Although, I think the 0 = 1, 1 = 2 ... stuff is really confusing. Is
> > there nothing we can do about that?
>
> OK, enum value of lp3943_pwm_output can be changed as below
> because LP3943_PWM_INVALID is not used anymore.
>
> enum lp3943_pwm_output {
> LP3943_PWM_OUT0,
> LP3943_PWM_OUT1,
> ...
> LP3943_PWM_OUT15,
> };
>
> Then, output index will match each enum integer value.
> Does it make sense?
Not really. IIRC the documentation said that LED0 (which I believe
you're calling OUT0 here) is located at pin one. So your enum above is
now incorrect isn't it? As *_OUT0 will be 0 and not 1? Or am I missing
something?
> > > +static int __init lp3943_init(void)
> > > +{
> > > + return i2c_add_driver(&lp3943_driver);
> > > +}
> > > +subsys_initcall(lp3943_init);
> > > +
> > > +static void __exit lp3943_exit(void)
> > > +{
> > > + i2c_del_driver(&lp3943_driver);
> > > +}
> > > +module_exit(lp3943_exit);
> >
> > I think you want to replace:
> > lp3943_init()
> > lp3943_exit
> >
> > With:
> > module_i2c_driver()
>
> This is related with initcall sequence.
> Some problem may happen if any GPIO or PWM consumer tries to request before
> LP3943 MFDs are added.
> For example, a GPIO is requested in _probe() of some device.
> Let's assume the GPIO number is in range of what LP3943 GPIO driver provided.
> Then, gpio_request() will be failed because the GPIO is invalid at this
> moment.
> If the device request again later, it will be OK, but we can't expect this
> situation for every driver.
> Some drivers request a GPIO only once in _probe(), other devices may request
> a GPIO in some cases.
> So, I think lp3943_init() should be defined as subsys_initcall() instead of
> module_init().
No I don't think so. Instead, you should use -EPROBE_DEFER in lieu of
messing around with initialisation orders.
--
Lee Jones
Linaro ST-Ericsson Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
