Messages in this thread | | | Date | Mon, 18 May 2009 11:27:59 +0200 | From | Marek Szyprowski <> | Subject | RE: [PATCH] [drivers] [SPI] SPI_GPIO: add support for controllers with missing MISO pin |
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Hello,
On Monday, May 18, 2009 10:57 AM Daniel Mack wrote:
> On Mon, May 18, 2009 at 09:34:12AM +0100, Ben Dooks wrote: > > > > > static inline int getmiso(const struct spi_device *spi) > > > > > { > > > > > - return !!gpio_get_value(SPI_MISO_GPIO); > > > > > + if (SPI_MISO_GPIO) > > > > > + return !!gpio_get_value(SPI_MISO_GPIO); > > > > > + else > > > > > + return 0; > > > > > } > > > > > > > > Is zero a good approximation for 'no gpio' ? > > > > > > Now I found that zero might be a valid gpio pin number on some > architectures > > > (it just means GPIO0 pin). This is imho a bit strange behavior of > gpiolib as > > > there should be also a special values for INVALID or NOGPIO cases. > Does > > > anyone have any ideas how such cases should be handled properly? > > > > I belive there is a gpio_is_valid() function to tell you precisely if > > the given GPIO is valid. > > And then -1 can be passed in from the platform data which will fail the > gpio_is_valid() test.
Ok. I will update my patch. Thank you for the idea.
Best regards -- Marek Szyprowski Samsung Poland R&D Center
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