[lkml]   [2015]   [Apr]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH] spi: rb4xx: Fix set_cs logic.
On Tue, Apr 21, 2015 at 01:01:22PM +0200, Bert Vermeulen wrote:
> On 04/21/2015 11:46 AM, Geert Uytterhoeven wrote:
> > On Mon, Apr 20, 2015 at 10:37 PM, Mark Brown <> wrote:

> >> No, the enable parameter *should* refer to chip select assertion (see
> >> how we handle GPIO chip selects). However it's possible that this
> >> device has an inverted chip select and should be registered with the
> >> SPI_CS_HIGH flag?

> > It's logic level:

> > * @set_cs: set the logic level of the chip select line. May be called
> > * from interrupt context.

> Right It's the implementation which doesn't really make sense IMHO: it
> always inverts the "enable" parameter (unless SPI_CS_HIGH is set), in
> keeping with the default active-low.

The default chip select is active low so an enebled chip select is low.

> So the docs are right, but "enable" doesn't match what it does. Chip select
> assertion would be a better API here. Is it worth fixing?

I suspect it's going to cause more breakage than it fixes with people
upstreaming things to change the sense of the paramter betwen kernel
versions - renaming the parameter to be clearer is probably about as
good as it gets.
[unhandled content-type:application/pgp-signature]
 \ /
  Last update: 2015-04-21 13:21    [W:0.077 / U:7.100 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site