Re: [PATCH 0/3] ARM: OMAP2+: omap_device: add dynamic pinctrl handling

From: Grygorii Strashko
Date: Wed Jul 17 2013 - 08:32:03 EST


On 07/17/2013 02:57 PM, Roger Quadros wrote:
Hi Grygorii,

On 07/17/2013 02:41 PM, Grygorii Strashko wrote:
Hi Tony, Kevin

This patch series introduces dynamic pinctrl handling in OMAP device framework
in the same way as it was before switching to DT.
This allow OMAP devices driver's developers to simply add dynamic pinctrl
handling for "default", "active", "idle", "sleep" PIN states in their drivers
by modifying DT definitions only - no modifications in drivers code are not needed.


Overall I like the idea but can we make a provision for device drivers to override
this default pin state handling?

The OMAP EHCI driver is one such special case where the wakeup mechanism is tied to pinctrl states
as it uses IO daisy chaining to implement wakeup.
So depending on whether wakeup needs to be enabled or not I must be able to chose whether
I put the pin in just "sleep" state or "sleep with wakeup" state.

I think, in this case you can't use default behavior and need to define
custom pins states like "sleep_wakeup"/"sleep_no_wakeup" and do not
define pins state with name "sleep', so Device core and OMAP device
framework will not touch your pins.


cheers,
-roger


Regards,
-grygorii
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/