Re: [PATCH] generic gpio: add default level to gpio_direction_output

On Thu, 1 Mar 2007 13:08:57 -0800
David Brownell <[email protected]> wrote:

> On Thursday 01 March 2007 6:32 am, Milan Svoboda wrote:
> > This patch adds second parameter to gpio_direction_output function.
> > This allows users to specify default output level.
> > 
> > Patch covers pxa and ixp4xx plus driver for pxa2xx_udc.
> > 
> > Patch is agains 2.6.21-rc1
> > 
> > What do you think about this attempt?
> 
> I'd avoid defining new GPIO_DIRECTION_OUT_{LOW,HIGH} symbols, and
> stick to the convention used in gpio_set_value().  If there were
> to be a new symbol, it should work with both functions; so that
> long "_DIRECTION" would be unwise.
> 
> Other than that, it's exactly what I'd want to see.  Andrew, Haavard;
> any comments?  Only PXA/IXP4XX and AT91/AVR32 need paired changes, so
> if there are no problems with those platforms, the rest can almost go
> independently.

I'm fine with this. I agree that no symbolic constants should be
necessary for a parameter called "level", as it should be pretty
obvious what is what.

The only downside I can think of is that this might slow down drivers
that change the direction a lot, like a bitbanging i2c driver. But at
least for i2c that shouldn't really be an issue since it usually needs
to be slowed down using udelay() anyway.

Haavard

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