Commit db690874 authored by David Brownell's avatar David Brownell Committed by Greg Kroah-Hartman

[PATCH] usb_interface power state

This updates the handling of power state for USB interfaces.

  - Formalizes an existing invariant:  interface "power state" is a boolean:
    ON when I/O is allowed, and FREEZE otherwise.  It does so by defining
    some inlined helpers, then using them.

  - Adds a useful invariant:  the only interfaces marked active are those
    bound to non-suspended drivers.  Later patches build on this invariant.

  - Simplifies the interface driver API (and removes some error paths) by
    removing the requirement that they record power state changes during
    suspend and resume callbacks.  Now usbcore does that.

A few drivers were simplified to address that last change.
Signed-off-by: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>

 drivers/usb/core/hub.c       |   33 +++++++++------------
 drivers/usb/core/message.c   |    1
 drivers/usb/core/usb.c       |   65 +++++++++++++++++++++++++++++++++----------
 drivers/usb/core/usb.h       |   18 +++++++++++
 drivers/usb/input/hid-core.c |    2 -
 drivers/usb/misc/usbtest.c   |   10 ------
 drivers/usb/net/pegasus.c    |    2 -
 drivers/usb/net/usbnet.c     |    2 -
 8 files changed, 85 insertions(+), 48 deletions(-)
parent 7586269c
......@@ -1624,7 +1624,7 @@ static int __usb_suspend_device (struct usb_device *udev, int port1,
struct usb_driver *driver;
intf = udev->actconfig->interface[i];
if (state.event <= intf->dev.power.power_state.event)
if (!is_active(intf))
continue;
if (!intf->dev.driver)
continue;
......@@ -1632,11 +1632,12 @@ static int __usb_suspend_device (struct usb_device *udev, int port1,
if (driver->suspend) {
status = driver->suspend(intf, state);
if (intf->dev.power.power_state.event != state.event
|| status)
if (status == 0)
mark_quiesced(intf);
else
dev_err(&intf->dev,
"suspend %d fail, code %d\n",
state.event, status);
"suspend error %d\n",
status);
}
/* only drivers with suspend() can ever resume();
......@@ -1787,7 +1788,7 @@ static int finish_port_resume(struct usb_device *udev)
struct usb_driver *driver;
intf = udev->actconfig->interface[i];
if (intf->dev.power.power_state.event == PM_EVENT_ON)
if (is_active(intf))
continue;
if (!intf->dev.driver) {
/* FIXME maybe force to alt 0 */
......@@ -1800,12 +1801,14 @@ static int finish_port_resume(struct usb_device *udev)
continue;
/* can we do better than just logging errors? */
mark_active(intf);
status = driver->resume(intf);
if (intf->dev.power.power_state.event != PM_EVENT_ON
|| status)
if (status < 0) {
mark_quiesced(intf);
dev_dbg(&intf->dev,
"resume fail, state %d code %d\n",
intf->dev.power.power_state.event, status);
"resume error %d\n",
status);
}
}
status = 0;
......@@ -1952,7 +1955,7 @@ static int remote_wakeup(struct usb_device *udev)
return status;
}
static int hub_suspend(struct usb_interface *intf, pm_message_t state)
static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
{
struct usb_hub *hub = usb_get_intfdata (intf);
struct usb_device *hdev = hub->hdev;
......@@ -1970,14 +1973,13 @@ static int hub_suspend(struct usb_interface *intf, pm_message_t state)
if (!udev)
continue;
down(&udev->serialize);
status = __usb_suspend_device(udev, port1, state);
status = __usb_suspend_device(udev, port1, msg);
up(&udev->serialize);
if (status < 0)
dev_dbg(&intf->dev, "suspend port %d --> %d\n",
port1, status);
}
intf->dev.power.power_state = state;
return 0;
}
......@@ -1988,9 +1990,6 @@ static int hub_resume(struct usb_interface *intf)
unsigned port1;
int status;
if (intf->dev.power.power_state.event == PM_EVENT_ON)
return 0;
for (port1 = 1; port1 <= hdev->maxchild; port1++) {
struct usb_device *udev;
u16 portstat, portchange;
......@@ -2024,8 +2023,6 @@ static int hub_resume(struct usb_interface *intf)
}
up(&udev->serialize);
}
intf->dev.power.power_state = PMSG_ON;
hub->resume_root_hub = 0;
hub_activate(hub);
return 0;
......
......@@ -1393,6 +1393,7 @@ int usb_set_configuration(struct usb_device *dev, int configuration)
intf->dev.dma_mask = dev->dev.dma_mask;
intf->dev.release = release_interface;
device_initialize (&intf->dev);
mark_quiesced(intf);
sprintf (&intf->dev.bus_id[0], "%d-%s:%d.%d",
dev->bus->busnum, dev->devpath,
configuration,
......
......@@ -107,10 +107,19 @@ static int usb_probe_interface(struct device *dev)
id = usb_match_id (intf, driver->id_table);
if (id) {
dev_dbg (dev, "%s - got id\n", __FUNCTION__);
/* Interface "power state" doesn't correspond to any hardware
* state whatsoever. We use it to record when it's bound to
* a driver that may start I/0: it's not frozen/quiesced.
*/
mark_active(intf);
intf->condition = USB_INTERFACE_BINDING;
error = driver->probe (intf, id);
intf->condition = error ? USB_INTERFACE_UNBOUND :
USB_INTERFACE_BOUND;
if (error) {
mark_quiesced(intf);
intf->condition = USB_INTERFACE_UNBOUND;
} else
intf->condition = USB_INTERFACE_BOUND;
}
return error;
......@@ -136,6 +145,7 @@ static int usb_unbind_interface(struct device *dev)
0);
usb_set_intfdata(intf, NULL);
intf->condition = USB_INTERFACE_UNBOUND;
mark_quiesced(intf);
return 0;
}
......@@ -299,6 +309,7 @@ int usb_driver_claim_interface(struct usb_driver *driver,
dev->driver = &driver->driver;
usb_set_intfdata(iface, priv);
iface->condition = USB_INTERFACE_BOUND;
mark_active(iface);
/* if interface was already added, bind now; else let
* the future device_add() bind it, bypassing probe()
......@@ -345,6 +356,7 @@ void usb_driver_release_interface(struct usb_driver *driver,
dev->driver = NULL;
usb_set_intfdata(iface, NULL);
iface->condition = USB_INTERFACE_UNBOUND;
mark_quiesced(iface);
}
/**
......@@ -1404,8 +1416,9 @@ void usb_buffer_unmap_sg (struct usb_device *dev, unsigned pipe,
static int usb_generic_suspend(struct device *dev, pm_message_t message)
{
struct usb_interface *intf;
struct usb_driver *driver;
struct usb_interface *intf;
struct usb_driver *driver;
int status;
if (dev->driver == &usb_generic_driver)
return usb_suspend_device (to_usb_device(dev), message);
......@@ -1417,21 +1430,34 @@ static int usb_generic_suspend(struct device *dev, pm_message_t message)
intf = to_usb_interface(dev);
driver = to_usb_driver(dev->driver);
/* there's only one USB suspend state */
if (intf->dev.power.power_state.event)
/* with no hardware, USB interfaces only use FREEZE and ON states */
if (!is_active(intf))
return 0;
if (driver->suspend)
return driver->suspend(intf, message);
return 0;
if (driver->suspend && driver->resume) {
status = driver->suspend(intf, message);
if (status)
dev_err(dev, "%s error %d\n", "suspend", status);
else
mark_quiesced(intf);
} else {
// FIXME else if there's no suspend method, disconnect...
dev_warn(dev, "no %s?\n", "suspend");
status = 0;
}
return status;
}
static int usb_generic_resume(struct device *dev)
{
struct usb_interface *intf;
struct usb_driver *driver;
struct usb_interface *intf;
struct usb_driver *driver;
int status;
if (dev->power.power_state.event == PM_EVENT_ON)
return 0;
/* devices resume through their hub */
/* devices resume through their hubs */
if (dev->driver == &usb_generic_driver)
return usb_resume_device (to_usb_device(dev));
......@@ -1442,8 +1468,19 @@ static int usb_generic_resume(struct device *dev)
intf = to_usb_interface(dev);
driver = to_usb_driver(dev->driver);
if (driver->resume)
return driver->resume(intf);
/* if driver was suspended, it has a resume method;
* however, sysfs can wrongly mark things as suspended
* (on the "no suspend method" FIXME path above)
*/
mark_active(intf);
if (driver->resume) {
status = driver->resume(intf);
if (status) {
dev_err(dev, "%s error %d\n", "resume", status);
mark_quiesced(intf);
}
} else
dev_warn(dev, "no %s?\n", "resume");
return 0;
}
......
......@@ -28,6 +28,24 @@ extern void usb_major_cleanup(void);
extern int usb_host_init(void);
extern void usb_host_cleanup(void);
/* Interfaces and their "power state" are owned by usbcore */
static inline void mark_active(struct usb_interface *f)
{
f->dev.power.power_state.event = PM_EVENT_ON;
}
static inline void mark_quiesced(struct usb_interface *f)
{
f->dev.power.power_state.event = PM_EVENT_FREEZE;
}
static inline int is_active(struct usb_interface *f)
{
return f->dev.power.power_state.event == PM_EVENT_ON;
}
/* for labeling diagnostics */
extern const char *usbcore_name;
......
......@@ -1887,7 +1887,6 @@ static int hid_suspend(struct usb_interface *intf, pm_message_t message)
struct hid_device *hid = usb_get_intfdata (intf);
usb_kill_urb(hid->urbin);
intf->dev.power.power_state = PMSG_SUSPEND;
dev_dbg(&intf->dev, "suspend\n");
return 0;
}
......@@ -1897,7 +1896,6 @@ static int hid_resume(struct usb_interface *intf)
struct hid_device *hid = usb_get_intfdata (intf);
int status;
intf->dev.power.power_state = PMSG_ON;
if (hid->open)
status = usb_submit_urb(hid->urbin, GFP_NOIO);
else
......
......@@ -1948,21 +1948,11 @@ usbtest_probe (struct usb_interface *intf, const struct usb_device_id *id)
static int usbtest_suspend (struct usb_interface *intf, pm_message_t message)
{
struct usbtest_dev *dev = usb_get_intfdata (intf);
down (&dev->sem);
intf->dev.power.power_state = PMSG_SUSPEND;
up (&dev->sem);
return 0;
}
static int usbtest_resume (struct usb_interface *intf)
{
struct usbtest_dev *dev = usb_get_intfdata (intf);
down (&dev->sem);
intf->dev.power.power_state = PMSG_ON;
up (&dev->sem);
return 0;
}
......
......@@ -1384,7 +1384,6 @@ static int pegasus_suspend (struct usb_interface *intf, pm_message_t message)
usb_kill_urb(pegasus->rx_urb);
usb_kill_urb(pegasus->intr_urb);
}
intf->dev.power.power_state = PMSG_SUSPEND;
return 0;
}
......@@ -1392,7 +1391,6 @@ static int pegasus_resume (struct usb_interface *intf)
{
struct pegasus *pegasus = usb_get_intfdata(intf);
intf->dev.power.power_state = PMSG_ON;
netif_device_attach (pegasus->net);
if (netif_running(pegasus->net)) {
pegasus->rx_urb->status = 0;
......
......@@ -1185,7 +1185,6 @@ int usbnet_suspend (struct usb_interface *intf, pm_message_t message)
netif_device_detach (dev->net);
(void) unlink_urbs (dev, &dev->rxq);
(void) unlink_urbs (dev, &dev->txq);
intf->dev.power.power_state = PMSG_SUSPEND;
return 0;
}
EXPORT_SYMBOL_GPL(usbnet_suspend);
......@@ -1194,7 +1193,6 @@ int usbnet_resume (struct usb_interface *intf)
{
struct usbnet *dev = usb_get_intfdata(intf);
intf->dev.power.power_state = PMSG_ON;
netif_device_attach (dev->net);
tasklet_schedule (&dev->bh);
return 0;
......
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