Here's a refresh of my driver model wakeup patch. Two
changes from last time:
- It sets up USB too, not just PCI. So keyboards and hubs,
plus a few network adapters, will have these attributes.
- Only devices that are known to have wakeup capabilities
have the attribute. So "find /sys/devices -name wakeup"
returns only "interesting" devices.
At this time, wakeup mechanisms need to be explicitly enabled
in userspace code; so this is in a sense a policy setting API
affecting runtime (and suspend-to-ram time) device-specific PM.
There will be some usbcore changes to follow this, assuming
this gets on the 2.6.14 train ... replacing current kluges.
Please merge...
- Dave
This is a refresh of an earlier patch to add "wakeup" support to
to the PM-core model:
* "struct device_pm_info" has two bits that are initialized as
part of setting up the enclosing struct device:
- "can_wakeup", reflecting hardware capabilities
- "may_wakeup", the policy setting (when CONFIG_PM)
* There's a writeable sysfs "wakeup" file, with one of two values:
- "enabled", when the policy is to allow wakeup
- "disabled", when the policy is not to allow it
The file is nonexistent when the device doesn't support wakeup.
* this patch includes support to initialize these bits for devices
that support PCI PM, or USB configurations handle remote wakeup.
Thing of it as providing one policy control knob affecting a driver.
In the future there may be others, with the overall device specific
policy satisfying several constraints defined from userspace.
Signed-off-by: David Brownell <[EMAIL PROTECTED]>
--- g26.orig/include/linux/pm.h 2005-08-02 07:58:25.000000000 -0700
+++ g26/include/linux/pm.h 2005-08-02 07:58:27.000000000 -0700
@@ -213,7 +213,9 @@ typedef u32 __bitwise pm_message_t;
struct dev_pm_info {
pm_message_t power_state;
+ unsigned can_wakeup:1;
#ifdef CONFIG_PM
+ unsigned should_wakeup:1;
pm_message_t prev_state;
void * saved_state;
atomic_t pm_users;
@@ -228,13 +230,30 @@ extern int device_power_down(pm_message_
extern void device_power_up(void);
extern void device_resume(void);
+/* wakeup changes take effect on device's next pm state change */
+#define device_init_wakeup(dev,val) \
+ ((dev)->power.can_wakeup = !!(val),((dev)->power.should_wakeup = 0))
+#define device_can_wakeup(dev) \
+ ((dev)->power.can_wakeup)
+
#ifdef CONFIG_PM
extern int device_suspend(pm_message_t state);
-#else
+
+#define device_set_wakeup_enable(dev,val) \
+ ((dev)->power.should_wakeup = (dev)->power.can_wakeup ? !!(val) : 0)
+#define device_may_wakeup(dev) \
+ (device_can_wakeup(dev) && (dev)->power.should_wakeup)
+
+#else /* !CONFIG_PM */
+
static inline int device_suspend(pm_message_t state)
{
return 0;
}
+
+#define device_set_wakeup_enable(dev,val) do{}while(0)
+#define device_may_wakeup(dev) (0)
+
#endif
#endif /* __KERNEL__ */
--- g26.orig/drivers/base/core.c 2005-08-02 07:58:25.000000000 -0700
+++ g26/drivers/base/core.c 2005-08-02 07:58:27.000000000 -0700
@@ -207,6 +207,7 @@ void device_initialize(struct device *de
{
kobj_set_kset_s(dev, devices_subsys);
kobject_init(&dev->kobj);
+ device_init_wakeup(dev, 0);
klist_init(&dev->klist_children);
INIT_LIST_HEAD(&dev->dma_pools);
init_MUTEX(&dev->sem);
--- g26.orig/drivers/base/power/sysfs.c 2005-08-02 07:58:25.000000000 -0700
+++ g26/drivers/base/power/sysfs.c 2005-08-02 07:58:27.000000000 -0700
@@ -48,6 +48,75 @@ static ssize_t state_store(struct device
static DEVICE_ATTR(state, 0644, state_show, state_store);
+/*
+ * wakeup - Report/change current wakeup option for device
+ *
+ * Some devices support "wakeup" events, which are hardware signals
+ * used to activate devices from suspended or low power states. Such
+ * devices have one of two wakeup options: "enabled" to issue the
+ * events, otherwise "disabled". The value is effective at the next
+ * system or device power state change. (Devices that don't support
+ * wakeup events have no value for this option.)
+ *
+ * Familiar examples of devices that can issue wakeup events include
+ * keyboards and mice (both PS2 and USB styles), power buttons, modems,
+ * "Wake-On-LAN" Ethernet links, GPIO lines, and more. Some events
+ * will wake the entire system from a suspend state; others may just
+ * wake up the device (if the system as a whole is already active).
+ * Some wakeup events use normal IRQ lines; other use special out
+ * of band signaling.
+ *
+ * It is the responsibility of device drivers to enable (or disable)
+ * wakeup signaling as part of changing system or device power states,
+ * respecting the policy choices provided through the driver model.
+ *
+ * Devices may not be able to generate wakeup events from all power
+ * states. Also, the events may be ignored in some configurations;
+ * for example, they might need help from other devices that aren't
+ * active, or which may have wakeup disabled. Some drivers rely on
+ * wakeup events internally (unless they are disabled), keeping
+ * their hardware in low power modes whenever they're unused. This
+ * saves runtime power, without requiring system-wide sleep states.
+ */
+
+static const char enabled[] = "enabled";
+static const char disabled[] = "disabled";
+
+static ssize_t
+wake_show(struct device * dev, struct device_attribute *attr, char * buf)
+{
+ return sprintf(buf, "%s\n", device_can_wakeup(dev)
+ ? (device_may_wakeup(dev) ? enabled : disabled)
+ : "");
+}
+
+static ssize_t
+wake_store(struct device * dev, struct device_attribute *attr,
+ const char * buf, size_t n)
+{
+ char *cp;
+ int len = n;
+
+ if (!device_can_wakeup(dev))
+ return -EINVAL;
+
+ cp = memchr(buf, '\n', n);
+ if (cp)
+ len = cp - buf;
+ if (len == sizeof enabled - 1
+ && strncmp(buf, enabled, sizeof enabled - 1) == 0)
+ device_set_wakeup_enable(dev, 1);
+ else if (len == sizeof disabled - 1
+ && strncmp(buf, disabled, sizeof disabled - 1) == 0)
+ device_set_wakeup_enable(dev, 0);
+ else
+ return -EINVAL;
+ return n;
+}
+
+static DEVICE_ATTR(wakeup, 0644, wake_show, wake_store);
+
+
static struct attribute * power_attrs[] = {
&dev_attr_state.attr,
NULL,
@@ -57,12 +126,29 @@ static struct attribute_group pm_attr_gr
.attrs = power_attrs,
};
+static struct attribute *wake_attrs[] = {
+ &dev_attr_state.attr,
+ /* same as "power" ... but adds "wakeup" */
+ &dev_attr_wakeup.attr,
+ NULL,
+};
+static struct attribute_group wake_attr_group = {
+ .name = "power",
+ .attrs = wake_attrs,
+};
+
int dpm_sysfs_add(struct device * dev)
{
- return sysfs_create_group(&dev->kobj, &pm_attr_group);
+ if (device_can_wakeup(dev))
+ return sysfs_create_group(&dev->kobj, &wake_attr_group);
+ else
+ return sysfs_create_group(&dev->kobj, &pm_attr_group);
}
void dpm_sysfs_remove(struct device * dev)
{
- sysfs_remove_group(&dev->kobj, &pm_attr_group);
+ if (device_can_wakeup(dev))
+ sysfs_remove_group(&dev->kobj, &wake_attr_group);
+ else
+ sysfs_remove_group(&dev->kobj, &pm_attr_group);
}
--- g26.orig/drivers/pci/pci.c 2005-08-02 07:58:25.000000000 -0700
+++ g26/drivers/pci/pci.c 2005-08-02 07:58:27.000000000 -0700
@@ -476,6 +476,10 @@ int pci_enable_wake(struct pci_dev *dev,
if (!pm)
return enable ? -EIO : 0;
+ /* don't enable unless policy set through driver core allows it */
+ if (!device_may_wakeup(&dev->dev) && enable)
+ return -EROFS;
+
/* Check device's ability to generate PME# */
pci_read_config_word(dev,pm+PCI_PM_PMC,&value);
--- g26.orig/drivers/pci/probe.c 2005-08-02 07:58:25.000000000 -0700
+++ g26/drivers/pci/probe.c 2005-08-02 07:58:27.000000000 -0700
@@ -571,6 +571,7 @@ static void pci_read_irq(struct pci_dev
static int pci_setup_device(struct pci_dev * dev)
{
u32 class;
+ u16 pm;
sprintf(pci_name(dev), "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
dev->bus->number, PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));
@@ -630,6 +631,14 @@ static int pci_setup_device(struct pci_d
dev->class = PCI_CLASS_NOT_DEFINED;
}
+ /* with PCI PM capability, it can maybe issue PME# */
+ pm = pci_find_capability(dev, PCI_CAP_ID_PM);
+ if (pm) {
+ pci_read_config_word(dev, pm + PCI_PM_PMC, &pm);
+ if (pm & PCI_PM_CAP_PME)
+ device_init_wakeup(&dev->dev, 1);
+ }
+
/* We found a fine healthy device, go go go... */
return 0;
}
@@ -749,11 +758,11 @@ pci_scan_device(struct pci_bus *bus, int
/* Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
set this higher, assuming the system even supports it. */
dev->dma_mask = 0xffffffff;
+ device_initialize(&dev->dev);
if (pci_setup_device(dev) < 0) {
kfree(dev);
return NULL;
}
- device_initialize(&dev->dev);
dev->dev.release = pci_release_dev;
pci_dev_get(dev);
--- g26.orig/drivers/usb/core/message.c 2005-08-02 07:58:25.000000000 -0700
+++ g26/drivers/usb/core/message.c 2005-08-02 07:58:27.000000000 -0700
@@ -1398,6 +1398,8 @@ free_interfaces:
dev->bus->busnum, dev->devpath,
configuration,
alt->desc.bInterfaceNumber);
+ if (cp->desc.bmAttributes & USB_CONFIG_ATT_WAKEUP)
+ device_init_wakeup(&intf->dev, 1);
}
kfree(new_interfaces);
