[alsa-devel] [PATCH 3/4] ASOC: WM8731 codec: add SPI support as well as I2C
gineera at aspect135.co.uk
Tue Sep 2 12:22:23 CEST 2008
On Monday 01 September 2008 15:02, you wrote:
> On Mon, Sep 01, 2008 at 02:52:08PM +0100, Alan Horstmann wrote:
> > in order to force use of SPI when (CONFIG_SND_SOC_WM8731_SPI) and
> > (CONFIG_I2C) are both defined. Or have we misunderstood the intention?
> > This is in 2 other places also in the patch.
> I've reworked the patch to allow a single kernel image to support both
> I2C and SPI which sidesteps this problem. I'll post this later today.
I am aware am new to the asoc stuff, and hesitate to comment, but it would
seem to me that Liams suggestion:
> It may be simpler to only have CONFIG_SND_SOC_WM8731_SPI and
> CONFIG_SND_SOC_WM8731_I2C definitions for all the codec drivers. These
> would be set by machine Kconfig.
is better, since it means one or the other, or both sets of code can be built.
Since in most applications the hardware is always wired up on a known bus, it
avoids unused code built in. Otherwise we would have to hand edit out
sections of code. (CONFIG_I2C) may be set because of other devices on that
bus. Does the codec ONLY work in spi master?
Then (CONFIG_SND_SOC_WM8731) is not really needed since it is
CONFIG_SND_SOC_WM8731_I2C || CONFIG_SND_SOC_WM8731_SPI
Essentially, where a hardware device can be connected in different ways
needing different code, a config option for each way is needed, rather than
being guessed from bus config options.
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