This is a note to let you know that I've just added the patch titled
mei: me: allow runtime pm for platform with D0i3
to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: mei-me-allow-runtime-pm-for-platform-with-d0i3.patch and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From cc365dcf0e56271bedf3de95f88922abe248e951 Mon Sep 17 00:00:00 2001
From: Tomas Winkler tomas.winkler@intel.com Date: Tue, 2 Jan 2018 12:01:41 +0200 Subject: mei: me: allow runtime pm for platform with D0i3
From: Tomas Winkler tomas.winkler@intel.com
commit cc365dcf0e56271bedf3de95f88922abe248e951 upstream.
From the pci power documentation:
"The driver itself should not call pm_runtime_allow(), though. Instead, it should let user space or some platform-specific code do that (user space can do it via sysfs as stated above)..."
However, the S0ix residency cannot be reached without MEI device getting into low power state. Hence, for mei devices that support D0i3, it's better to make runtime power management mandatory and not rely on the system integration such as udev rules. This policy cannot be applied globally as some older platforms were found to have broken power management.
Cc: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Tomas Winkler tomas.winkler@intel.com Reviewed-by: Alexander Usyskin alexander.usyskin@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/misc/mei/pci-me.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
--- a/drivers/misc/mei/pci-me.c +++ b/drivers/misc/mei/pci-me.c @@ -238,8 +238,11 @@ static int mei_me_probe(struct pci_dev * */ mei_me_set_pm_domain(dev);
- if (mei_pg_is_enabled(dev)) + if (mei_pg_is_enabled(dev)) { pm_runtime_put_noidle(&pdev->dev); + if (hw->d0i3_supported) + pm_runtime_allow(&pdev->dev); + }
dev_dbg(&pdev->dev, "initialization successful.\n");
Patches currently in stable-queue which might be from tomas.winkler@intel.com are
queue-4.14/mei-me-allow-runtime-pm-for-platform-with-d0i3.patch