[PATCH 1/3] spi: s3c64xx: move "cs-gpio" from subnode to SPI DT node
Mark Brown
broonie at kernel.org
Wed Jul 16 10:09:05 PDT 2014
On Tue, Jul 15, 2014 at 07:30:08PM +0200, Tomasz Figa wrote:
> On 15.07.2014 14:20, Naveen Krishna Chatradhi wrote:
> > /* The CS line is asserted/deasserted by the gpio pin */
> > - if (sdd->cs_gpio)
> > - cs->line = of_get_named_gpio(data_np, "cs-gpio", 0);
> > + cs->line = spi->cs_gpio;
> >
> > if (!gpio_is_valid(cs->line)) {
> This check is wrong when native chip select is used. However I'm not
> sure how to distinguish this from a situation when invalid GPIO was
> specified, because cs->line will be -ENOENT in both cases. Mark, any ideas?
Hrm. I'd *hope* that of_get_named_gpio() would distinguish between the
property being there but unparsable and the property being absent. Does
it not do this?
> > - if (!of_find_property(pdev->dev.of_node, "cs-gpio", NULL))
> > + if (!of_find_property(pdev->dev.of_node, "cs-gpios", NULL))
> > sdd->cs_gpio = false;
> What is this boolean flag used for now? If cs->line now either contains
> a valid GPIO or a negative error, why gpio_is_valid() couldn't be used
> on it? I believe it was done correctly in previous version.
We ought to handle the errors differently depending on where they came
from - an unspecified GPIO means use the physical chip select but a GPIO
we fail to obtain is an error we should handle.
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