Re: [patch 2.6.20-rc2] gpio_direction_output() needs an initial value

[David Brownell <david-b@pacbell.net>]

On Thursday 01 March 2007 9:48 pm, Andrew Victor wrote:
> hi David,
> 
> > It's been pointed out that output GPIOs should have an initial value, to
> > avoid signal glitching ... among other things, it can be some time before
> > a driver is ready.  This patch corrects that oversight, fixing
> 
> For the AT91 changes:
>   Acked-by: Andrew Victor <andrew@sanpeople.com>
> 
> 
> > --- g26.orig/drivers/spi/atmel_spi.c	2007-02-28 12:47:43.000000000 -0800
> > +++ g26/drivers/spi/atmel_spi.c	2007-03-01 15:29:30.000000000 -0800
> 
> > -		gpio_direction_output(npcs_pin);
> > +		gpio_direction_output(npcs_pin, !(spi->mode & SPI_CS_HIGH));
> >  	}
> 
> As mentioned previously (by Walter Tuppa), wouldn't it be better to just
> change this to:
>      cs_deactivate(spi);

That *does* deactivate the chipselect, as the initial value.
Given this function signature change, some initial value must
be specified, and that expression uses the inactive value...