Re: [PATCH 1/2] spi: bcm2835: add spi-bcm2835aux driver for the auxiliar spi1 and spi2

On 02.07.2015, at 06:57, Noralf Trønnes [off-list ref] wrote:


Den 01.07.2015 21:39, skrev Martin Sperl:

quoted

quoted

On 30.06.2015, at 19:42, Mark Brown [off-list ref] wrote:

This looks relevant:

quoted

quoted

quoted

On 22.06.2015, at 16:55, Jakub Kiciński [off-list ref] wrote:
As mentioned by Noralf UART1 is quite commonly used on Compute Modules.
Proper driver - perhaps modelled as a bus - seems like a prerequisite
for this work.  You are also not using IRQ mux in DT binding example
which is very misleading.

[...]

quoted

Finally asking for a recommendation with regards to using a bus
to arbitrate access to the enable register there was no feedback
how this could be get implemented...

Maybe you can use drivers/mfd/syscon.c to enable shared access to the
aux enable register. Then the spi driver could get the regmap with:
aux_regmap = syscon_regmap_lookup_by_phandle(np, "syscon");

Seems as if you found an answer to my original question of if
there is a framework to handle this.

About sharing the aux interrupt, could this be implemented in irq-bcm2835
as a Bank 3?

Obviously it could, but the question is if it is not more overhead than using
a shared interrupt (requesting an interrupt with the shared flag set) in the
first place (like this driver currently does or i2c and USB do).

I am working on a new version to make use of syscon.

Thanks, Martin



_______________________________________________
linux-rpi-kernel mailing list
linux-rpi-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-rpi-kernel