Re: [PATCH v1 0/4] ACPI / LPSS: fix system hangup on BYT

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

On Fri, 2014-11-07 at 01:37 +0100, Rafael J. Wysocki wrote:
> On Wednesday, November 05, 2014 06:34:44 PM Andy Shevchenko wrote:
> > The Intel BayTrail based machines have different configuration of the Low Power
> > Sub System (LPSS) IP. The LPSS contains few host controllers, such as I2C, SPI,
> > I2C and common DMA IP to serve DMA transfers. Unfortunately the DMA IP has no
> > power control accessible for software / OS. It goes automatically down whenever
> > last device goes to sleep and turned on when one of them is turned on. When
> > user tries to access the powered off DMA device the system hangs.
> > 
> > This patch series addressing the issue. Rafael suggested to create a 'proxy'
> > device which makes DMA to be powered on on the certain points of time.
> > 
> > Vinod, we would like to push this via Rafael's tree, so, please Ack or NAck the
> > patch 4/4.
> > 
> > Scott, do you have a chance to test this patch series against last linux-pm
> > tree on HP laptops? I would appreciate your Tested-by tag.
> > 
> > Andy Shevchenko (4):
> >   ACPI / LPSS: add all LPSS devices to the specific power domain
> >   ACPI / LPSS: allow to use specific PM domain during ->probe()
> >   ACPI / LPSS: introduce a 'proxy' device to power on LPSS for DMA
> >   dmaengine: dw: enable runtime PM
> 
> I'm essentially fine with this series, but I'm not sure what the status of
> the Scott's testing is.  Can you please tell me and Scott what in particular
> you wanted him to test?

He complained that HP laptop didn't reboot nicely and hangs the system
until he blacklisted dw_dmac driver.

-- 
Andy Shevchenko <andriy.shevchenko@intel.com>
Intel Finland Oy