4.4-stable review patch. If anyone has any objections, please let me know.
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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: stable@vger.kernel.org v4.13+ 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 @@ -230,8 +230,11 @@ static int mei_me_probe(struct pci_dev * if (!pci_dev_run_wake(pdev)) 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");