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authorLinus Torvalds <torvalds@linux-foundation.org>2019-09-18 10:33:46 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-09-18 10:33:46 -0700
commitc6b48dad92aedaa9bdc013ee495cb5b1bbdf1f11 (patch)
tree8d0bbf19d75fc1bf546ed1b05b560ea2df54689e /drivers/usb/core/devio.c
parent1f7d290a7275edb270dbee13212c37cb59940221 (diff)
parentfb9617edf6c0e1b86a6595cd92dd3f84595221d9 (diff)
Merge tag 'usb-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB updates from Greg KH: "Here is the big set of USB patches for 5.4-rc1. Two major chunks of code are moving out of the tree and into the staging directory, uwb and wusb (wireless USB support), because there are no devices that actually use this protocol anymore, and what we have today probably doesn't work at all given that the maintainers left many many years ago. So move it to staging where it will be removed in a few releases if no one screams. Other than that, lots of little things. The usual gadget and xhci and usb serial driver updates, along with a bunch of sysfs file cleanups due to the driver core changes to support that. Nothing really major, just constant forward progress. All of these have been in linux-next for a while with no reported issues" * tag 'usb-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (159 commits) USB: usbcore: Fix slab-out-of-bounds bug during device reset usb: cdns3: Remove redundant dev_err call in cdns3_probe() USB: rio500: Fix lockdep violation USB: rio500: simplify locking usb: mtu3: register a USB Role Switch for dual role mode usb: common: add USB GPIO based connection detection driver usb: common: create Kconfig file usb: roles: get usb-role-switch from parent usb: roles: Add fwnode_usb_role_switch_get() function device connection: Add fwnode_connection_find_match() usb: roles: Introduce stubs for the exiting functions in role.h dt-bindings: usb: mtu3: add properties about USB Role Switch dt-bindings: usb: add binding for USB GPIO based connection detection driver dt-bindings: connector: add optional properties for Type-B dt-binding: usb: add usb-role-switch property usbip: Implement SG support to vhci-hcd and stub driver usb: roles: intel: Enable static DRD mode for role switch xhci-ext-caps.c: Add property to disable Intel SW switch usb: dwc3: remove generic PHY calibrate() calls usb: core: phy: add support for PHY calibration ...
Diffstat (limited to 'drivers/usb/core/devio.c')
-rw-r--r--drivers/usb/core/devio.c108
1 files changed, 101 insertions, 7 deletions
diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c
index e3696601e43b..3f899552f6e3 100644
--- a/drivers/usb/core/devio.c
+++ b/drivers/usb/core/devio.c
@@ -44,10 +44,19 @@
#include "usb.h"
+#ifdef CONFIG_PM
+#define MAYBE_CAP_SUSPEND USBDEVFS_CAP_SUSPEND
+#else
+#define MAYBE_CAP_SUSPEND 0
+#endif
+
#define USB_MAXBUS 64
#define USB_DEVICE_MAX (USB_MAXBUS * 128)
#define USB_SG_SIZE 16384 /* split-size for large txs */
+/* Mutual exclusion for ps->list in resume vs. release and remove */
+static DEFINE_MUTEX(usbfs_mutex);
+
struct usb_dev_state {
struct list_head list; /* state list */
struct usb_device *dev;
@@ -57,14 +66,17 @@ struct usb_dev_state {
struct list_head async_completed;
struct list_head memory_list;
wait_queue_head_t wait; /* wake up if a request completed */
+ wait_queue_head_t wait_for_resume; /* wake up upon runtime resume */
unsigned int discsignr;
struct pid *disc_pid;
const struct cred *cred;
sigval_t disccontext;
unsigned long ifclaimed;
u32 disabled_bulk_eps;
- bool privileges_dropped;
unsigned long interface_allowed_mask;
+ int not_yet_resumed;
+ bool suspend_allowed;
+ bool privileges_dropped;
};
struct usb_memory {
@@ -694,9 +706,7 @@ static void driver_disconnect(struct usb_interface *intf)
destroy_async_on_interface(ps, ifnum);
}
-/* The following routines are merely placeholders. There is no way
- * to inform a user task about suspend or resumes.
- */
+/* We don't care about suspend/resume of claimed interfaces */
static int driver_suspend(struct usb_interface *intf, pm_message_t msg)
{
return 0;
@@ -707,12 +717,32 @@ static int driver_resume(struct usb_interface *intf)
return 0;
}
+/* The following routines apply to the entire device, not interfaces */
+void usbfs_notify_suspend(struct usb_device *udev)
+{
+ /* We don't need to handle this */
+}
+
+void usbfs_notify_resume(struct usb_device *udev)
+{
+ struct usb_dev_state *ps;
+
+ /* Protect against simultaneous remove or release */
+ mutex_lock(&usbfs_mutex);
+ list_for_each_entry(ps, &udev->filelist, list) {
+ WRITE_ONCE(ps->not_yet_resumed, 0);
+ wake_up_all(&ps->wait_for_resume);
+ }
+ mutex_unlock(&usbfs_mutex);
+}
+
struct usb_driver usbfs_driver = {
.name = "usbfs",
.probe = driver_probe,
.disconnect = driver_disconnect,
.suspend = driver_suspend,
.resume = driver_resume,
+ .supports_autosuspend = 1,
};
static int claimintf(struct usb_dev_state *ps, unsigned int ifnum)
@@ -991,9 +1021,12 @@ static int usbdev_open(struct inode *inode, struct file *file)
INIT_LIST_HEAD(&ps->async_completed);
INIT_LIST_HEAD(&ps->memory_list);
init_waitqueue_head(&ps->wait);
+ init_waitqueue_head(&ps->wait_for_resume);
ps->disc_pid = get_pid(task_pid(current));
ps->cred = get_current_cred();
smp_wmb();
+
+ /* Can't race with resume; the device is already active */
list_add_tail(&ps->list, &dev->filelist);
file->private_data = ps;
usb_unlock_device(dev);
@@ -1019,7 +1052,10 @@ static int usbdev_release(struct inode *inode, struct file *file)
usb_lock_device(dev);
usb_hub_release_all_ports(dev, ps);
+ /* Protect against simultaneous resume */
+ mutex_lock(&usbfs_mutex);
list_del_init(&ps->list);
+ mutex_unlock(&usbfs_mutex);
for (ifnum = 0; ps->ifclaimed && ifnum < 8*sizeof(ps->ifclaimed);
ifnum++) {
@@ -1027,7 +1063,8 @@ static int usbdev_release(struct inode *inode, struct file *file)
releaseintf(ps, ifnum);
}
destroy_all_async(ps);
- usb_autosuspend_device(dev);
+ if (!ps->suspend_allowed)
+ usb_autosuspend_device(dev);
usb_unlock_device(dev);
usb_put_dev(dev);
put_pid(ps->disc_pid);
@@ -1621,7 +1658,8 @@ static int proc_do_submiturb(struct usb_dev_state *ps, struct usbdevfs_urb *uurb
if (as->usbm)
num_sgs = 0;
- u += sizeof(struct async) + sizeof(struct urb) + uurb->buffer_length +
+ u += sizeof(struct async) + sizeof(struct urb) +
+ (as->usbm ? 0 : uurb->buffer_length) +
num_sgs * sizeof(struct scatterlist);
ret = usbfs_increase_memory_usage(u);
if (ret)
@@ -2273,7 +2311,8 @@ static int proc_get_capabilities(struct usb_dev_state *ps, void __user *arg)
caps = USBDEVFS_CAP_ZERO_PACKET | USBDEVFS_CAP_NO_PACKET_SIZE_LIM |
USBDEVFS_CAP_REAP_AFTER_DISCONNECT | USBDEVFS_CAP_MMAP |
- USBDEVFS_CAP_DROP_PRIVILEGES | USBDEVFS_CAP_CONNINFO_EX;
+ USBDEVFS_CAP_DROP_PRIVILEGES |
+ USBDEVFS_CAP_CONNINFO_EX | MAYBE_CAP_SUSPEND;
if (!ps->dev->bus->no_stop_on_short)
caps |= USBDEVFS_CAP_BULK_CONTINUATION;
if (ps->dev->bus->sg_tablesize)
@@ -2376,6 +2415,47 @@ static int proc_drop_privileges(struct usb_dev_state *ps, void __user *arg)
return 0;
}
+static int proc_forbid_suspend(struct usb_dev_state *ps)
+{
+ int ret = 0;
+
+ if (ps->suspend_allowed) {
+ ret = usb_autoresume_device(ps->dev);
+ if (ret == 0)
+ ps->suspend_allowed = false;
+ else if (ret != -ENODEV)
+ ret = -EIO;
+ }
+ return ret;
+}
+
+static int proc_allow_suspend(struct usb_dev_state *ps)
+{
+ if (!connected(ps))
+ return -ENODEV;
+
+ WRITE_ONCE(ps->not_yet_resumed, 1);
+ if (!ps->suspend_allowed) {
+ usb_autosuspend_device(ps->dev);
+ ps->suspend_allowed = true;
+ }
+ return 0;
+}
+
+static int proc_wait_for_resume(struct usb_dev_state *ps)
+{
+ int ret;
+
+ usb_unlock_device(ps->dev);
+ ret = wait_event_interruptible(ps->wait_for_resume,
+ READ_ONCE(ps->not_yet_resumed) == 0);
+ usb_lock_device(ps->dev);
+
+ if (ret != 0)
+ return -EINTR;
+ return proc_forbid_suspend(ps);
+}
+
/*
* NOTE: All requests here that have interface numbers as parameters
* are assuming that somehow the configuration has been prevented from
@@ -2570,6 +2650,15 @@ static long usbdev_do_ioctl(struct file *file, unsigned int cmd,
case USBDEVFS_GET_SPEED:
ret = ps->dev->speed;
break;
+ case USBDEVFS_FORBID_SUSPEND:
+ ret = proc_forbid_suspend(ps);
+ break;
+ case USBDEVFS_ALLOW_SUSPEND:
+ ret = proc_allow_suspend(ps);
+ break;
+ case USBDEVFS_WAIT_FOR_RESUME:
+ ret = proc_wait_for_resume(ps);
+ break;
}
/* Handle variable-length commands */
@@ -2643,15 +2732,20 @@ static void usbdev_remove(struct usb_device *udev)
{
struct usb_dev_state *ps;
+ /* Protect against simultaneous resume */
+ mutex_lock(&usbfs_mutex);
while (!list_empty(&udev->filelist)) {
ps = list_entry(udev->filelist.next, struct usb_dev_state, list);
destroy_all_async(ps);
wake_up_all(&ps->wait);
+ WRITE_ONCE(ps->not_yet_resumed, 0);
+ wake_up_all(&ps->wait_for_resume);
list_del_init(&ps->list);
if (ps->discsignr)
kill_pid_usb_asyncio(ps->discsignr, EPIPE, ps->disccontext,
ps->disc_pid, ps->cred);
}
+ mutex_unlock(&usbfs_mutex);
}
static int usbdev_notify(struct notifier_block *self,