Re: [PATCH 2/2] spi: img-spfi: fix spfi_setup by removing gpio_request_one

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Hi Sifan,

On Mon, Jul 27, 2015 at 5:11 AM, Sifan Naeem <sifan.naeem@xxxxxxxxxx> wrote:
> spfi_setup may be called many times bye the spi framework, but
> gpio_request_one can only be called once without freeing, repeatedly
> calling gpio_request_one will cause an error to be thrown, which causes
> the request to spi_setup to be marked as failed.
>
> We can simply use gpio_direction_output to set the direction of the
> gpio instead of gpio_request_one to put the gpio in to initial state,
> after which the spi framework can control the chipselect line via gpio
> using gpio_set_value.

I don't think we want to leave the CS GPIOs un-requested.  Instead, we
could either request them all at probe() time (and then set direction
in setup()) or have a per-spi_device flag that indicates whether or
not the GPIO has been requested.

-Andrew
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