PCI PM: Run-time callbacks for PCI bus type

Introduce run-time PM callbacks for the PCI bus type.  Make the new
callbacks work in analogy with the existing system sleep PM
callbacks, so that the drivers already converted to struct dev_pm_ops
can use their suspend and resume routines for run-time PM without
modifications.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 133 insertions, 27 deletions

diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index e5d47be3c6d7..f9a0aec3abcf 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -17,6 +17,7 @@
 #include <linux/slab.h>
 #include <linux/sched.h>
 #include <linux/cpu.h>
+#include <linux/pm_runtime.h>
 #include "pci.h"
 
 struct pci_dynid {
@@ -404,6 +405,35 @@ static void pci_device_shutdown(struct device *dev)
         pci_msix_shutdown(pci_dev);
 }
 
+#ifdef CONFIG_PM_OPS
+
+/* Auxiliary functions used for system resume and run-time resume. */
+
+/**
+ * pci_restore_standard_config - restore standard config registers of PCI device
+ * @pci_dev: PCI device to handle
+ */
+static int pci_restore_standard_config(struct pci_dev *pci_dev)
+{
+        pci_update_current_state(pci_dev, PCI_UNKNOWN);
+
+        if (pci_dev->current_state != PCI_D0) {
+                int error = pci_set_power_state(pci_dev, PCI_D0);
+                if (error)
+                        return error;
+        }
+
+        return pci_restore_state(pci_dev);
+}
+
+static void pci_pm_default_resume_early(struct pci_dev *pci_dev)
+{
+        pci_restore_standard_config(pci_dev);
+        pci_fixup_device(pci_fixup_resume_early, pci_dev);
+}
+
+#endif
+
 #ifdef CONFIG_PM_SLEEP
 
 /*
@@ -520,29 +550,6 @@ static int pci_legacy_resume(struct device *dev)
 
 /* Auxiliary functions used by the new power management framework */
 
-/**
- * pci_restore_standard_config - restore standard config registers of PCI device
- * @pci_dev: PCI device to handle
- */
-static int pci_restore_standard_config(struct pci_dev *pci_dev)
-{
-        pci_update_current_state(pci_dev, PCI_UNKNOWN);
-
-        if (pci_dev->current_state != PCI_D0) {
-                int error = pci_set_power_state(pci_dev, PCI_D0);
-                if (error)
-                        return error;
-        }
-
-        return pci_restore_state(pci_dev);
-}
-
-static void pci_pm_default_resume_noirq(struct pci_dev *pci_dev)
-{
-        pci_restore_standard_config(pci_dev);
-        pci_fixup_device(pci_fixup_resume_early, pci_dev);
-}
-
 static void pci_pm_default_resume(struct pci_dev *pci_dev)
 {
         pci_fixup_device(pci_fixup_resume, pci_dev);
@@ -581,6 +588,17 @@ static int pci_pm_prepare(struct device *dev)
         struct device_driver *drv = dev->driver;
         int error = 0;
 
+        /*
+         * PCI devices suspended at run time need to be resumed at this
+         * point, because in general it is necessary to reconfigure them for
+         * system suspend.  Namely, if the device is supposed to wake up the
+         * system from the sleep state, we may need to reconfigure it for this
+         * purpose.  In turn, if the device is not supposed to wake up the
+         * system from the sleep state, we'll have to prevent it from signaling
+         * wake-up.
+         */
+        pm_runtime_resume(dev);
+
         if (drv && drv->pm && drv->pm->prepare)
                 error = drv->pm->prepare(dev);
 
@@ -595,6 +613,13 @@ static void pci_pm_complete(struct device *dev)
                 drv->pm->complete(dev);
 }
 
+#else /* !CONFIG_PM_SLEEP */
+
+#define pci_pm_prepare  NULL
+#define pci_pm_complete NULL
+
+#endif /* !CONFIG_PM_SLEEP */
+
 #ifdef CONFIG_SUSPEND
 
 static int pci_pm_suspend(struct device *dev)
@@ -681,7 +706,7 @@ static int pci_pm_resume_noirq(struct device *dev)
         struct device_driver *drv = dev->driver;
         int error = 0;
 
-        pci_pm_default_resume_noirq(pci_dev);
+        pci_pm_default_resume_early(pci_dev);
 
         if (pci_has_legacy_pm_support(pci_dev))
                 return pci_legacy_resume_early(dev);
@@ -879,7 +904,7 @@ static int pci_pm_restore_noirq(struct device *dev)
         struct device_driver *drv = dev->driver;
         int error = 0;
 
-        pci_pm_default_resume_noirq(pci_dev);
+        pci_pm_default_resume_early(pci_dev);
 
         if (pci_has_legacy_pm_support(pci_dev))
                 return pci_legacy_resume_early(dev);
@@ -931,6 +956,84 @@ static int pci_pm_restore(struct device *dev)
 
 #endif /* !CONFIG_HIBERNATION */
 
+#ifdef CONFIG_PM_RUNTIME
+
+static int pci_pm_runtime_suspend(struct device *dev)
+{
+        struct pci_dev *pci_dev = to_pci_dev(dev);
+        const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
+        pci_power_t prev = pci_dev->current_state;
+        int error;
+
+        if (!pm || !pm->runtime_suspend)
+                return -ENOSYS;
+
+        error = pm->runtime_suspend(dev);
+        suspend_report_result(pm->runtime_suspend, error);
+        if (error)
+                return error;
+
+        pci_fixup_device(pci_fixup_suspend, pci_dev);
+
+        if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
+            && pci_dev->current_state != PCI_UNKNOWN) {
+                WARN_ONCE(pci_dev->current_state != prev,
+                        "PCI PM: State of device not saved by %pF\n",
+                        pm->runtime_suspend);
+                return 0;
+        }
+
+        if (!pci_dev->state_saved)
+                pci_save_state(pci_dev);
+
+        pci_finish_runtime_suspend(pci_dev);
+
+        return 0;
+}
+
+static int pci_pm_runtime_resume(struct device *dev)
+{
+        struct pci_dev *pci_dev = to_pci_dev(dev);
+        const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
+
+        if (!pm || !pm->runtime_resume)
+                return -ENOSYS;
+
+        pci_pm_default_resume_early(pci_dev);
+        __pci_enable_wake(pci_dev, PCI_D0, true, false);
+        pci_fixup_device(pci_fixup_resume, pci_dev);
+
+        return pm->runtime_resume(dev);
+}
+
+static int pci_pm_runtime_idle(struct device *dev)
+{
+        const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
+
+        if (!pm)
+                return -ENOSYS;
+
+        if (pm->runtime_idle) {
+                int ret = pm->runtime_idle(dev);
+                if (ret)
+                        return ret;
+        }
+
+        pm_runtime_suspend(dev);
+
+        return 0;
+}
+
+#else /* !CONFIG_PM_RUNTIME */
+
+#define pci_pm_runtime_suspend  NULL
+#define pci_pm_runtime_resume   NULL
+#define pci_pm_runtime_idle     NULL
+
+#endif /* !CONFIG_PM_RUNTIME */
+
+#ifdef CONFIG_PM_OPS
+
 const struct dev_pm_ops pci_dev_pm_ops = {
         .prepare = pci_pm_prepare,
         .complete = pci_pm_complete,
@@ -946,15 +1049,18 @@ const struct dev_pm_ops pci_dev_pm_ops = {
         .thaw_noirq = pci_pm_thaw_noirq,
         .poweroff_noirq = pci_pm_poweroff_noirq,
         .restore_noirq = pci_pm_restore_noirq,
+        .runtime_suspend = pci_pm_runtime_suspend,
+        .runtime_resume = pci_pm_runtime_resume,
+        .runtime_idle = pci_pm_runtime_idle,
 };
 
 #define PCI_PM_OPS_PTR  (&pci_dev_pm_ops)
 
-#else /* !CONFIG_PM_SLEEP */
+#else /* !COMFIG_PM_OPS */
 
 #define PCI_PM_OPS_PTR  NULL
 
-#endif /* !CONFIG_PM_SLEEP */
+#endif /* !COMFIG_PM_OPS */
 
 /**
  * __pci_register_driver - register a new pci driver