Messages in this thread | | | Date | Fri, 29 Jun 2012 09:30:51 -0600 | From | Stephen Warren <> | Subject | Re: [PATCH] regulator: fixed: support deferred probe for DT GPIOs |
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On 06/28/2012 07:25 PM, Mark Brown wrote: > On Thu, Jun 28, 2012 at 04:31:32PM -0600, Stephen Warren wrote: > >> static struct fixed_voltage_config * >> -of_get_fixed_voltage_config(struct device *dev) >> +of_get_fixed_voltage_config(struct device *dev, bool >> *defer_probe) > > This is pretty contorted, we should just be able to pass the > return value back more directly and of course ideally gpiolib would > be doing the -EPROBE_DEFER for us anyway (I did send a patch for > this, Grant didn't apply it due to a mostly unrelated issue in the > current probe deferral implementation). Or just defer if we don't > get a config passed back or something.
I did consider making of_get_fixed_voltage_config() return a result code, but then it needs some other way of returning the pointer, so that seemed just as convoluted. Oh, I suppose it could use ERR_PTR() to do that; that'd be nice and simple. Would that do?
Re: gpiolib doing it: How is that possible? of_get_named_gpio() certainly can return -EPROBE_DEFER, but the caller would still need to check it. The ideal case might be to just do:
ret = gpio_request(of_get_named_gpio(...)); if (ret) return ret;
and have gpio_request pass -EPROBE_DEFER from input to output.
i.e. only check the gpio_request() result code, not the of_get_named_gpio() result code, and rely on gpio_request() to do validation later.
But gpio_request takes an unsigned int, so the error code wouldn't survive the translation:-(
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