RE: [PATCHv2] wlcore: spi: add wl18xx support
From: Reizer, Eyal
Date: Tue Apr 19 2016 - 10:35:38 EST
> > > > It is also part of the generic spi.h (include/Linux/spi/spi.h),
> > > > already part of " struct spi_device" So it seemed redundant adding
> > > > another mechanism for implementing the same.
> > > > Platform that interact with a wilink need to use it, and platforms
> > > > that don't have this capability will probably not interact with a
> > > > wilink device
> > > using SPI.
> > >
> > > The cs_gpio field in spi_device belongs to the spi host controller,
> > > no other slave driver uses it.
> > >
> > > I wasn't asking for a duplication of this mechanism, but an
> > > interface to use it properly. Internally, the spi core uses the spi_set_cs()
> function to pick a CS.
> > > Find a way to use that rather than reimplementing it incorrectly.
> > >
> > Understood. As this special CS manipulation is unique to wspi (wilink
> > spi) I think the best option is to move this gpio allocation into
> > wlcore_spi as a new device tree entry used only by this driver.
> > If you agree I will submit a v3.
> I don't think that can work either: aside of not solving the problem of wilink
> devices on spi controllers that don't use gpio, it also doesn't solve the
> problem of what happens when the driver manually triggers the gpio to hold
> the CS signal while another driver talks to a different device using another CS
> on the same controller.
Ok, understood. Will look into it.