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 drivers/acpi/acpi_lpss.c | 94 +++++++++++++++++++++++++++++++++--------------- drivers/dma/dw/core.c | 11 ++++++ 2 files changed, 76 insertions(+), 29 deletions(-) -- 2.1.1 -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
