PCI ACPI: Rework PCI handling of wake-up
authorRafael J. Wysocki <rjw@sisk.pl>
Mon, 7 Jul 2008 01:34:48 +0000 (03:34 +0200)
committerJesse Barnes <jbarnes@virtuousgeek.org>
Mon, 7 Jul 2008 23:26:28 +0000 (16:26 -0700)
* Introduce function acpi_pm_device_sleep_wake() for enabling and
  disabling the system wake-up capability of devices that are power
  manageable by ACPI.

* Introduce function acpi_bus_can_wakeup() allowing other (dependent)
  subsystems to check if ACPI is able to enable the system wake-up
  capability of given device.

* Introduce callback .sleep_wake() in struct pci_platform_pm_ops and
  for the ACPI PCI 'driver' make it use acpi_pm_device_sleep_wake().

* Introduce callback .can_wakeup() in struct pci_platform_pm_ops and
  for the ACPI 'driver' make it use acpi_bus_can_wakeup().

* Move the PME# handlig code out of pci_enable_wake() and split it
  into two functions, pci_pme_capable() and pci_pme_active(),
  allowing the caller to check if given device is capable of
  generating PME# from given power state and to enable/disable the
  device's PME# functionality, respectively.

* Modify pci_enable_wake() to use the new ACPI callbacks and the new
  PME#-related functions.

* Drop the generic .platform_enable_wakeup() callback that is not
  used any more.

* Introduce device_set_wakeup_capable() that will set the
  power.can_wakeup flag of given device.

* Rework PCI device PM initialization so that, if given device is
  capable of generating wake-up events, either natively through the
  PME# mechanism, or with the help of the platform, its
  power.can_wakeup flag is set and its power.should_wakeup flag is
  unset as appropriate.

* Make ACPI set the power.can_wakeup flag for devices found to be
  wake-up capable by it.

* Make the ACPI wake-up code enable/disable GPEs for devices that
  have the wakeup.flags.prepared flag set (which means that their
  wake-up power has been enabled).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
drivers/acpi/bus.c
drivers/acpi/glue.c
drivers/acpi/sleep/main.c
drivers/acpi/sleep/wakeup.c
drivers/base/power/sysfs.c
drivers/pci/pci-acpi.c
drivers/pci/pci.c
drivers/pci/pci.h
drivers/pci/probe.c
include/acpi/acpi_bus.h
include/linux/pm_wakeup.h

index b9b69d9629b585a461b09af679533eb9d0c386a9..fc1110d6a0787a5d2da8e85b0fe3b9e7b15c6fa8 100644 (file)
@@ -306,6 +306,17 @@ bool acpi_bus_power_manageable(acpi_handle handle)
 
 EXPORT_SYMBOL(acpi_bus_power_manageable);
 
+bool acpi_bus_can_wakeup(acpi_handle handle)
+{
+       struct acpi_device *device;
+       int result;
+
+       result = acpi_bus_get_device(handle, &device);
+       return result ? false : device->wakeup.flags.valid;
+}
+
+EXPORT_SYMBOL(acpi_bus_can_wakeup);
+
 /* --------------------------------------------------------------------------
                                 Event Management
    -------------------------------------------------------------------------- */
index 06f8634fe58b192498ad73c5e4d4a4e715b01cf3..87c5d456e180fa27d130fee74ec19c967a851d70 100644 (file)
@@ -166,6 +166,8 @@ static int acpi_bind_one(struct device *dev, acpi_handle handle)
                                "firmware_node");
                ret = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj,
                                "physical_node");
+               if (acpi_dev->wakeup.flags.valid)
+                       device_set_wakeup_capable(dev, true);
        }
 
        return 0;
index 4addf8ad50ae5fd8f235462f2bc03d937678106b..af7f4663deaa40c044a7be4aff7775e9db407559 100644 (file)
@@ -468,6 +468,31 @@ int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p)
                *d_min_p = d_min;
        return d_max;
 }
+
+/**
+ *     acpi_pm_device_sleep_wake - enable or disable the system wake-up
+ *                                  capability of given device
+ *     @dev: device to handle
+ *     @enable: 'true' - enable, 'false' - disable the wake-up capability
+ */
+int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
+{
+       acpi_handle handle;
+       struct acpi_device *adev;
+
+       if (!device_may_wakeup(dev))
+               return -EINVAL;
+
+       handle = DEVICE_ACPI_HANDLE(dev);
+       if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
+               printk(KERN_DEBUG "ACPI handle has no context!\n");
+               return -ENODEV;
+       }
+
+       return enable ?
+               acpi_enable_wakeup_device_power(adev, acpi_target_sleep_state) :
+               acpi_disable_wakeup_device_power(adev);
+}
 #endif
 
 static void acpi_power_off_prepare(void)
index 7422a2213944ed0cffba015c56c841a2bed0a87d..38655eb132dcca3a42ac2db56f2daf79d3b10286 100644 (file)
@@ -66,13 +66,15 @@ void acpi_enable_wakeup_device(u8 sleep_state)
        list_for_each_safe(node, next, &acpi_wakeup_device_list) {
                struct acpi_device *dev =
                        container_of(node, struct acpi_device, wakeup_list);
+
                if (!dev->wakeup.flags.valid)
                        continue;
+
                /* If users want to disable run-wake GPE,
                 * we only disable it for wake and leave it for runtime
                 */
-               if (!dev->wakeup.state.enabled ||
-                   sleep_state > (u32) dev->wakeup.sleep_state) {
+               if ((!dev->wakeup.state.enabled && !dev->wakeup.flags.prepared)
+                   || sleep_state > (u32) dev->wakeup.sleep_state) {
                        if (dev->wakeup.flags.run_wake) {
                                spin_unlock(&acpi_device_lock);
                                /* set_gpe_type will disable GPE, leave it like that */
@@ -110,8 +112,9 @@ void acpi_disable_wakeup_device(u8 sleep_state)
 
                if (!dev->wakeup.flags.valid)
                        continue;
-               if (!dev->wakeup.state.enabled ||
-                   sleep_state > (u32) dev->wakeup.sleep_state) {
+
+               if ((!dev->wakeup.state.enabled && !dev->wakeup.flags.prepared)
+                   || sleep_state > (u32) dev->wakeup.sleep_state) {
                        if (dev->wakeup.flags.run_wake) {
                                spin_unlock(&acpi_device_lock);
                                acpi_set_gpe_type(dev->wakeup.gpe_device,
index d11f74b038db2039026a6f4a6b1a490e994b51f6..596aeecfdffe4be62c7e6773046e9c23d4dd37bb 100644 (file)
@@ -6,9 +6,6 @@
 #include <linux/string.h>
 #include "power.h"
 
-int (*platform_enable_wakeup)(struct device *dev, int is_on);
-
-
 /*
  *     wakeup - Report/change current wakeup option for device
  *
index 6bc0d8c870afe1bbc283b873af42abc9388bebac..7764768b6a0e7dfc225c76693b3be997df4b926f 100644 (file)
@@ -299,10 +299,30 @@ static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
        return error;
 }
 
+static bool acpi_pci_can_wakeup(struct pci_dev *dev)
+{
+       acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
+
+       return handle ? acpi_bus_can_wakeup(handle) : false;
+}
+
+static int acpi_pci_sleep_wake(struct pci_dev *dev, bool enable)
+{
+       int error = acpi_pm_device_sleep_wake(&dev->dev, enable);
+
+       if (!error)
+               dev_printk(KERN_INFO, &dev->dev,
+                               "wake-up capability %s by ACPI\n",
+                               enable ? "enabled" : "disabled");
+       return error;
+}
+
 static struct pci_platform_pm_ops acpi_pci_platform_pm = {
        .is_manageable = acpi_pci_power_manageable,
        .set_state = acpi_pci_set_power_state,
        .choose_state = acpi_pci_choose_state,
+       .can_wakeup = acpi_pci_can_wakeup,
+       .sleep_wake = acpi_pci_sleep_wake,
 };
 
 /* ACPI bus type */
index 20e28077b96d44acc6f00f8569b66c785947bfe1..a6b1b6f96abc6c7124b9b22b3ffec56a3513d462 100644 (file)
@@ -380,7 +380,8 @@ static struct pci_platform_pm_ops *pci_platform_pm;
 
 int pci_set_platform_pm(struct pci_platform_pm_ops *ops)
 {
-       if (!ops->is_manageable || !ops->set_state || !ops->choose_state)
+       if (!ops->is_manageable || !ops->set_state || !ops->choose_state
+           || !ops->sleep_wake || !ops->can_wakeup)
                return -EINVAL;
        pci_platform_pm = ops;
        return 0;
@@ -403,6 +404,17 @@ static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev)
                        pci_platform_pm->choose_state(dev) : PCI_POWER_ERROR;
 }
 
+static inline bool platform_pci_can_wakeup(struct pci_dev *dev)
+{
+       return pci_platform_pm ? pci_platform_pm->can_wakeup(dev) : false;
+}
+
+static inline int platform_pci_sleep_wake(struct pci_dev *dev, bool enable)
+{
+       return pci_platform_pm ?
+                       pci_platform_pm->sleep_wake(dev, enable) : -ENODEV;
+}
+
 /**
  * pci_raw_set_power_state - Use PCI PM registers to set the power state of
  *                           given PCI device
@@ -1035,6 +1047,56 @@ int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
        return pcibios_set_pcie_reset_state(dev, state);
 }
 
+/**
+ * pci_pme_capable - check the capability of PCI device to generate PME#
+ * @dev: PCI device to handle.
+ * @pm: PCI PM capability offset of the device.
+ * @state: PCI state from which device will issue PME#.
+ */
+static bool pci_pme_capable(struct pci_dev *dev, int pm, pci_power_t state)
+{
+       u16 pmc;
+
+       if (!pm)
+               return false;
+
+       /* Check device's ability to generate PME# from given state */
+       pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
+
+       pmc &= PCI_PM_CAP_PME_MASK;
+       pmc >>= ffs(PCI_PM_CAP_PME_MASK) - 1;   /* First bit of mask */
+
+       return !!(pmc & (1 << state));
+}
+
+/**
+ * pci_pme_active - enable or disable PCI device's PME# function
+ * @dev: PCI device to handle.
+ * @pm: PCI PM capability offset of the device.
+ * @enable: 'true' to enable PME# generation; 'false' to disable it.
+ *
+ * The caller must verify that the device is capable of generating PME# before
+ * calling this function with @enable equal to 'true'.
+ */
+static void pci_pme_active(struct pci_dev *dev, int pm, bool enable)
+{
+       u16 pmcsr;
+
+       if (!pm)
+               return;
+
+       pci_read_config_word(dev, pm + PCI_PM_CTRL, &pmcsr);
+       /* Clear PME_Status by writing 1 to it and enable PME# */
+       pmcsr |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
+       if (!enable)
+               pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
+
+       pci_write_config_word(dev, pm + PCI_PM_CTRL, pmcsr);
+
+       dev_printk(KERN_INFO, &dev->dev, "PME# %s\n",
+                       enable ? "enabled" : "disabled");
+}
+
 /**
  * pci_enable_wake - enable PCI device as wakeup event source
  * @dev: PCI device affected
@@ -1046,66 +1108,83 @@ int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
  * called automatically by this routine.
  *
  * Devices with legacy power management (no standard PCI PM capabilities)
- * always require such platform hooks.  Depending on the platform, devices
- * supporting the standard PCI PME# signal may require such platform hooks;
- * they always update bits in config space to allow PME# generation.
+ * always require such platform hooks.
  *
- * -EIO is returned if the device can't ever be a wakeup event source.
- * -EINVAL is returned if the device can't generate wakeup events from
- * the specified PCI state.  Returns zero if the operation is successful.
+ * RETURN VALUE:
+ * 0 is returned on success
+ * -EINVAL is returned if device is not supposed to wake up the system
+ * Error code depending on the platform is returned if both the platform and
+ * the native mechanism fail to enable the generation of wake-up events
  */
 int pci_enable_wake(struct pci_dev *dev, pci_power_t state, int enable)
 {
        int pm;
-       int status;
-       u16 value;
-
-       /* Note that drivers should verify device_may_wakeup(&dev->dev)
-        * before calling this function.  Platform code should report
-        * errors when drivers try to enable wakeup on devices that
-        * can't issue wakeups, or on which wakeups were disabled by
-        * userspace updating the /sys/devices.../power/wakeup file.
-        */
+       int error = 0;
+       bool pme_done = false;
 
-       status = call_platform_enable_wakeup(&dev->dev, enable);
-
-       /* find PCI PM capability in list */
-       pm = pci_find_capability(dev, PCI_CAP_ID_PM);
+       if (!device_may_wakeup(&dev->dev))
+               return -EINVAL;
 
-       /* If device doesn't support PM Capabilities, but caller wants to
-        * disable wake events, it's a NOP.  Otherwise fail unless the
-        * platform hooks handled this legacy device already.
+       /*
+        * According to "PCI System Architecture" 4th ed. by Tom Shanley & Don
+        * Anderson we should be doing PME# wake enable followed by ACPI wake
+        * enable.  To disable wake-up we call the platform first, for symmetry.
         */
-       if (!pm)
-               return enable ? status : 0;
 
-       /* Check device's ability to generate PME# */
-       pci_read_config_word(dev,pm+PCI_PM_PMC,&value);
+       if (!enable && platform_pci_can_wakeup(dev))
+               error = platform_pci_sleep_wake(dev, false);
 
-       value &= PCI_PM_CAP_PME_MASK;
-       value >>= ffs(PCI_PM_CAP_PME_MASK) - 1;   /* First bit of mask */
-
-       /* Check if it can generate PME# from requested state. */
-       if (!value || !(value & (1 << state))) {
-               /* if it can't, revert what the platform hook changed,
-                * always reporting the base "EINVAL, can't PME#" error
-                */
-               if (enable)
-                       call_platform_enable_wakeup(&dev->dev, 0);
-               return enable ? -EINVAL : 0;
+       pm = pci_find_capability(dev, PCI_CAP_ID_PM);
+       if (!enable || pci_pme_capable(dev, pm, state)) {
+               pci_pme_active(dev, pm, enable);
+               pme_done = true;
        }
 
-       pci_read_config_word(dev, pm + PCI_PM_CTRL, &value);
+       if (enable && platform_pci_can_wakeup(dev))
+               error = platform_pci_sleep_wake(dev, true);
 
-       /* Clear PME_Status by writing 1 to it and enable PME# */
-       value |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
+       return pme_done ? 0 : error;
+}
 
-       if (!enable)
-               value &= ~PCI_PM_CTRL_PME_ENABLE;
+/**
+ * pci_pm_init - Initialize PM functions of given PCI device
+ * @dev: PCI device to handle.
+ */
+void pci_pm_init(struct pci_dev *dev)
+{
+       int pm;
+       u16 pmc;
 
-       pci_write_config_word(dev, pm + PCI_PM_CTRL, value);
+       /* find PCI PM capability in list */
+       pm = pci_find_capability(dev, PCI_CAP_ID_PM);
+       if (!pm)
+               return;
+       /* Check device's ability to generate PME# */
+       pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
 
-       return 0;
+       if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
+               dev_err(&dev->dev, "unsupported PM cap regs version (%u)\n",
+                       pmc & PCI_PM_CAP_VER_MASK);
+               return;
+       }
+
+       if (pmc & PCI_PM_CAP_PME_MASK) {
+               dev_printk(KERN_INFO, &dev->dev,
+                       "PME# supported from%s%s%s%s%s\n",
+                       (pmc & PCI_PM_CAP_PME_D0) ? " D0" : "",
+                       (pmc & PCI_PM_CAP_PME_D1) ? " D1" : "",
+                       (pmc & PCI_PM_CAP_PME_D2) ? " D2" : "",
+                       (pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "",
+                       (pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : "");
+               /*
+                * Make device's PM flags reflect the wake-up capability, but
+                * let the user space enable it to wake up the system as needed.
+                */
+               device_set_wakeup_capable(&dev->dev, true);
+               device_set_wakeup_enable(&dev->dev, false);
+               /* Disable the PME# generation functionality */
+               pci_pme_active(dev, pm, false);
+       }
 }
 
 int
index 0cd2e719933b11c46d8742f07af7f2201264fb89..b08dfc9746afea97ec7e31b070605bbab61771e6 100644 (file)
@@ -17,6 +17,11 @@ extern void pci_cleanup_rom(struct pci_dev *dev);
  *                 platform; to be used during system-wide transitions from a
  *                 sleeping state to the working state and vice versa
  *
+ * @can_wakeup - returns 'true' if given device is capable of waking up the
+ *               system from a sleeping state
+ *
+ * @sleep_wake - enables/disables the system wake up capability of given device
+ *
  * If given platform is generally capable of power managing PCI devices, all of
  * these callbacks are mandatory.
  */
@@ -24,9 +29,12 @@ struct pci_platform_pm_ops {
        bool (*is_manageable)(struct pci_dev *dev);
        int (*set_state)(struct pci_dev *dev, pci_power_t state);
        pci_power_t (*choose_state)(struct pci_dev *dev);
+       bool (*can_wakeup)(struct pci_dev *dev);
+       int (*sleep_wake)(struct pci_dev *dev, bool enable);
 };
 
 extern int pci_set_platform_pm(struct pci_platform_pm_ops *ops);
+extern void pci_pm_init(struct pci_dev *dev);
 
 extern int pci_user_read_config_byte(struct pci_dev *dev, int where, u8 *val);
 extern int pci_user_read_config_word(struct pci_dev *dev, int where, u16 *val);
index 2f0ae70710d6ef25f9db8d9e9965d36d90e02c1b..b1724cf31b669ef459d3250aa8fae48b38e4c7fa 100644 (file)
@@ -860,49 +860,6 @@ int pci_cfg_space_size_ext(struct pci_dev *dev)
        return PCI_CFG_SPACE_SIZE;
 }
 
-/**
- * pci_disable_pme - Disable the PME function of PCI device
- * @dev: PCI device affected
- * -EINVAL is returned if PCI device doesn't support PME.
- * Zero is returned if the PME is supported and can be disabled.
- */
-static int pci_disable_pme(struct pci_dev *dev)
-{
-       int pm;
-       u16 value;
-
-       /* find PCI PM capability in list */
-       pm = pci_find_capability(dev, PCI_CAP_ID_PM);
-
-       /* If device doesn't support PM Capabilities, it means that PME is
-        * not supported.
-        */
-       if (!pm)
-               return -EINVAL;
-       /* Check device's ability to generate PME# */
-       pci_read_config_word(dev, pm + PCI_PM_PMC, &value);
-
-       value &= PCI_PM_CAP_PME_MASK;
-       /* Check if it can generate PME# */
-       if (!value) {
-               /*
-                * If it is zero, it means that PME is still unsupported
-                * although there exists the PM capability.
-                */
-               return -EINVAL;
-       }
-
-       pci_read_config_word(dev, pm + PCI_PM_CTRL, &value);
-
-       /* Clear PME_Status by writing 1 to it */
-       value |= PCI_PM_CTRL_PME_STATUS ;
-       /* Disable PME enable bit */
-       value &= ~PCI_PM_CTRL_PME_ENABLE;
-       pci_write_config_word(dev, pm + PCI_PM_CTRL, value);
-
-       return 0;
-}
-
 int pci_cfg_space_size(struct pci_dev *dev)
 {
        int pos;
@@ -1010,7 +967,6 @@ static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
        }
 
        pci_vpd_pci22_init(dev);
-       pci_disable_pme(dev);
 
        return dev;
 }
@@ -1031,6 +987,9 @@ void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
        /* Fix up broken headers */
        pci_fixup_device(pci_fixup_header, dev);
 
+       /* Initialize power management of the device */
+       pci_pm_init(dev);
+
        /*
         * Add the device to our list of discovered devices
         * and the bus list for fixup functions, etc.
index 071daf8db600df53ba8a32449b27711c7cf43366..7ab5a611e43ff289c34a88a63b54ade498f4a8e7 100644 (file)
@@ -337,6 +337,7 @@ int acpi_bus_get_status(struct acpi_device *device);
 int acpi_bus_get_power(acpi_handle handle, int *state);
 int acpi_bus_set_power(acpi_handle handle, int state);
 bool acpi_bus_power_manageable(acpi_handle handle);
+bool acpi_bus_can_wakeup(acpi_handle handle);
 #ifdef CONFIG_ACPI_PROC_EVENT
 int acpi_bus_generate_proc_event(struct acpi_device *device, u8 type, int data);
 int acpi_bus_generate_proc_event4(const char *class, const char *bid, u8 type, int data);
@@ -379,6 +380,7 @@ acpi_handle acpi_get_pci_rootbridge_handle(unsigned int, unsigned int);
 
 #ifdef CONFIG_PM_SLEEP
 int acpi_pm_device_sleep_state(struct device *, int *);
+int acpi_pm_device_sleep_wake(struct device *, bool);
 #else /* !CONFIG_PM_SLEEP */
 static inline int acpi_pm_device_sleep_state(struct device *d, int *p)
 {
index f0d0b2cb8d205ce6de169cae5c60c7a3166ef11a..3af0c8d05cdcb2e89cd70cc5de16fb264a771bd0 100644 (file)
@@ -35,6 +35,11 @@ static inline void device_init_wakeup(struct device *dev, int val)
        dev->power.can_wakeup = dev->power.should_wakeup = !!val;
 }
 
+static inline void device_set_wakeup_capable(struct device *dev, int val)
+{
+       dev->power.can_wakeup = !!val;
+}
+
 static inline int device_can_wakeup(struct device *dev)
 {
        return dev->power.can_wakeup;
@@ -47,21 +52,7 @@ static inline void device_set_wakeup_enable(struct device *dev, int val)
 
 static inline int device_may_wakeup(struct device *dev)
 {
-       return dev->power.can_wakeup & dev->power.should_wakeup;
-}
-
-/*
- * Platform hook to activate device wakeup capability, if that's not already
- * handled by enable_irq_wake() etc.
- * Returns zero on success, else negative errno
- */
-extern int (*platform_enable_wakeup)(struct device *dev, int is_on);
-
-static inline int call_platform_enable_wakeup(struct device *dev, int is_on)
-{
-       if (platform_enable_wakeup)
-               return (*platform_enable_wakeup)(dev, is_on);
-       return 0;
+       return dev->power.can_wakeup && dev->power.should_wakeup;
 }
 
 #else /* !CONFIG_PM */
@@ -80,11 +71,6 @@ static inline int device_can_wakeup(struct device *dev)
 #define device_set_wakeup_enable(dev, val)     do {} while (0)
 #define device_may_wakeup(dev)                 0
 
-static inline int call_platform_enable_wakeup(struct device *dev, int is_on)
-{
-       return 0;
-}
-
 #endif /* !CONFIG_PM */
 
 #endif /* _LINUX_PM_WAKEUP_H */