Messages in this thread | | | Date | Fri, 31 Jul 2009 16:43:40 +0300 | Subject | Re: [PATCH] regulator: Add GPIO enable control to fixed voltage regulator driver | From | Roger Quadros <> |
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On Fri, Jul 31, 2009 at 4:34 PM, Mark Brown<broonie@opensource.wolfsonmicro.com> wrote: > On Fri, Jul 31, 2009 at 03:25:36PM +0200, pHilipp Zabel wrote: >> On Fri, Jul 31, 2009 at 3:10 PM, Mark >> Brown<broonie@opensource.wolfsonmicro.com> wrote: > >> > This isn't needed, just use an invalid GPIO value (zero or less). > >> Negative only, actually. Zero itself is a valid GPIO number (which is >> a bit unfortunate because if you forget to initialize .gpio, it will >> default to GPIO #0). > >> If you drop .use_gpio_control, use gpio_is_valid(data->gpio) for this check: > > Feh, better print a warning for GPIO 0 for at least a kernel release. > Fortunately we've got no mainline users of fixed voltage regulators. >
I think most architectures start their GPIO numbering from 0. By 'a release', do you mean next Kernel release will be indexing GPIOs from 1?
>> > Same comment as above with regard to the error message. ?It would be >> > nice to have the default state passed in as platform data if you can't >> > read it back to help avoid bouncing supplies at startup. ?IIRC >> > gpio_get_value() will generally take a good stab at giving the current >> > state no matter if the GPIO is input our output but I'd need to check. > >> I think this is not clearly defined in the GPIO API document, so it >> could be architecture dependent. > > It's not particularly; having checked gpiolib just passes this straight > through to the underlying driver. Since they'd have to go out of their > way to do something unconstructive it should be safe to do the read and > we can worry about problem cases if they crop up. > >> > If you mark the comments with /** they'll get picked up by kerneldoc. > >> Maybe following the style in Documentation/kernel-doc-nano-HOWTO.txt >> would be worthwhile, then. > > Indeed. >
Taken other suggestions for v2. Thanks Mark and Philipp. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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