Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge branch 'pci/pm'
- Avoid redundant delay on transition from D3hot to D3cold if the device
was already in D3hot (Brian Norris)
- Prevent runtime suspend until devices are fully initialized to avoid
saving incompletely configured device state (Brian Norris)
* pci/pm:
PCI/PM: Prevent runtime suspend until devices are fully initialized
PCI/PM: Avoid redundant delays on D3hot->D3cold
+18
-1
+8
drivers/pci/bus.c
+8
drivers/pci/bus.c
···
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#include <linux/of.h>
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#include <linux/of_platform.h>
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#include <linux/platform_device.h>
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+
#include <linux/pm_runtime.h>
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#include <linux/proc_fs.h>
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#include <linux/slab.h>
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···
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}
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put_device(&pdev->dev);
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}
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+
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+
/*
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+
* Enable runtime PM, which potentially allows the device to
384
+
* suspend immediately, only after the PCI state has been
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+
* configured completely.
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+
*/
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+
pm_runtime_enable(&dev->dev);
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if (!dn || of_device_is_available(dn))
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pci_dev_allow_binding(dev);
+10
-1
drivers/pci/pci.c
+10
-1
drivers/pci/pci.c
···
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|| (state == PCI_D2 && !dev->d2_support))
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return -EIO;
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+
if (dev->current_state == state)
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+
return 0;
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+
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pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
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if (PCI_POSSIBLE_ERROR(pmcsr)) {
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pci_err(dev, "Unable to change power state from %s to %s, device inaccessible\n",
···
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poweron:
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pci_pm_power_up_and_verify_state(dev);
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pm_runtime_forbid(&dev->dev);
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+
3200
+
/*
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+
* Runtime PM will be enabled for the device when it has been fully
3202
+
* configured, but since its parent and suppliers may suspend in
3203
+
* the meantime, prevent them from doing so by changing the
3204
+
* device's runtime PM status to "active".
3205
+
*/
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pm_runtime_set_active(&dev->dev);
3203
-
pm_runtime_enable(&dev->dev);
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}
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static unsigned long pci_ea_flags(struct pci_dev *dev, u8 prop)