Move all port power policy evaluation to usb_port_runtime_suspend().
Makes it clearer what blocks port power off and is preparation for
follow on changes that
1/ make a usb_port a proper (device model) parent
of a usb_device
2/ advertise to userspace what constraints are keeping a
port powered
3/ changing the meaning of the usb_port runtime suspended
state.
4/ add new constraints peer-port-power-state and connect_type
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
drivers/usb/core/hub.c | 16 +++++++++++++++-
drivers/usb/core/hub.h | 7 +++++++
drivers/usb/core/port.c | 22 ++++++++++++++++++++--
3 files changed, 42 insertions(+), 3 deletions(-)
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 683f528f5ea7..0e4c85380760 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -2066,6 +2066,20 @@ void usb_disconnect(struct usb_device **pdev)
put_device(&udev->dev);
}
+/* outside of khubd context a device may be deleted at any time */
+struct usb_device *usb_port_get_child(struct usb_port *port_dev)
+{
+ struct usb_device *udev = NULL;
+
+ spin_lock_irq(&device_state_lock);
+ udev = port_dev->child;
+ if (udev)
+ get_device(&udev->dev);
+ spin_unlock_irq(&device_state_lock);
+
+ return udev;
+}
+
#ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
static void show_string(struct usb_device *udev, char *id, char *string)
{
@@ -3039,7 +3053,7 @@ int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
usb_set_device_state(udev, USB_STATE_SUSPENDED);
}
- if (status == 0 && !udev->do_remote_wakeup && udev->persist_enabled) {
+ if (status == 0) {
pm_runtime_put_sync(&port_dev->dev);
port_dev->did_runtime_put = true;
}
diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h
index 44508d41c095..4e34365e41e3 100644
--- a/drivers/usb/core/hub.h
+++ b/drivers/usb/core/hub.h
@@ -110,3 +110,10 @@ extern int usb_set_port_feature(struct usb_device *hdev,
extern void usb_assign_port_poweroff(struct usb_hub *hub, int port1, int val);
#define usb_set_port_poweroff(h, p) usb_assign_port_poweroff(h, p, 1)
#define usb_clear_port_poweroff(h, p) usb_assign_port_poweroff(h, p, 0)
+extern struct usb_device *usb_port_get_child(struct usb_port *port_dev);
+static inline void usb_port_put_child(struct usb_device *udev)
+{
+ if (!udev)
+ return;
+ put_device(&udev->dev);
+}
diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c
index 094a9d0e31c7..6257c1ec5e2d 100644
--- a/drivers/usb/core/port.c
+++ b/drivers/usb/core/port.c
@@ -93,6 +93,25 @@ static int usb_port_runtime_resume(struct device *dev)
return retval;
}
+static const char *power_on_reason(struct usb_port *port_dev)
+{
+ s32 flag = PM_QOS_FLAG_NO_POWER_OFF;
+ const char *reason = NULL;
+ struct usb_device *udev;
+
+ if (dev_pm_qos_flags(&port_dev->dev, flag) == PM_QOS_FLAGS_ALL)
+ return "pm_qos_no_power_off";
+
+ udev = usb_port_get_child(port_dev);
+ if (udev && udev->do_remote_wakeup)
+ reason = "wakeup enabled";
+ else if (udev && !udev->persist_enabled)
+ reason = "persist disabled";
+ usb_port_put_child(udev);
+
+ return reason;
+}
+
static int usb_port_runtime_suspend(struct device *dev)
{
struct usb_port *port_dev = to_usb_port(dev);
@@ -105,8 +124,7 @@ static int usb_port_runtime_suspend(struct device *dev)
if (!hub)
return -EINVAL;
- if (dev_pm_qos_flags(&port_dev->dev, PM_QOS_FLAG_NO_POWER_OFF)
- == PM_QOS_FLAGS_ALL)
+ if (power_on_reason(port_dev))
return -EAGAIN;
usb_autopm_get_interface(intf);
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
