Re: [PATCH 07/18] dmaengine/amba-pl08x: Enable/Disable amba_pclk withchannel requests

From: Linus Walleij
Date: Tue Aug 09 2011 - 15:50:45 EST

On Wed, Aug 3, 2011 at 2:55 PM, Russell King - ARM Linux
<linux@xxxxxxxxxxxxxxxx> wrote:
> On Tue, Aug 02, 2011 at 11:05:38AM +0200, Linus Walleij wrote:
>> On Sun, Jul 31, 2011 at 7:04 PM, Russell King - ARM Linux
>> <linux@xxxxxxxxxxxxxxxx> wrote:
>> > On Sun, Jul 31, 2011 at 02:04:47AM +0200, Linus Walleij wrote:
>> >>
>> >> ..and while it will just cause some double refcounts on the clock,
>> >> it makes sense to delete the pclk manipulation from the PL022
>> >> driver code as part of the patch, like this:
>> >
>> > Yes, this looks fine.  Shall I wrap it up as part of my patch?
>> Yes please.
>> Acked-by.
> Can you give this a try - this adds runtime PM to the primecell core,
> updates the SPI driver for those changes, and adds runtime PM to the
> MMCI driver.  I've briefly tested this on Versatile PB926, though
> obviously not the SPI stuff very much because Versatile has no SPI
> peripherals.
> I chose the PCI methodology to this - rather than having every driver
> fiddle about with enabling runtime PM, that's dealt with in the core
> and instead, drivers just do a put() in their probe and a balancing
> get() in their remove function to activate runtime PM for the device.

Sorry for the delay.

It works like a charm. I've tested it on U300 with a loopback test
and MMC and for both it works perfectly and the reference
counter goes to zero when unused.

Tested-by: Linus Walleij <linus.walleij@xxxxxxxxxx>

Linus Walleij
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