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HID: usbhid: remove custom locking from usbhid_open/close

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Now that HID core enforces serialization of transport driver open/close
calls we can remove custom locking from usbhid driver.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This commit is contained in:
Dmitry Torokhov 2017-06-06 23:59:36 -07:00 committed by Jiri Kosina
parent 85ae911331
commit e399396a6b
1 changed files with 52 additions and 61 deletions
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113
drivers/hid/usbhid/hid-core.c
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@ -70,8 +70,6 @@ MODULE_PARM_DESC(quirks, "Add/modify USB HID quirks by specifying "
/*
* Input submission and I/O error handler.
*/
static DEFINE_MUTEX(hid_open_mut);
static void hid_io_error(struct hid_device *hid);
static int hid_submit_out(struct hid_device *hid);
static int hid_submit_ctrl(struct hid_device *hid);
@ -680,50 +678,48 @@ static int hid_get_class_descriptor(struct usb_device *dev, int ifnum,
static int usbhid_open(struct hid_device *hid)
{
struct usbhid_device *usbhid = hid->driver_data;
int res = 0;
int res;
mutex_lock(&hid_open_mut);
if (!hid->open++) {
res = usb_autopm_get_interface(usbhid->intf);
/* the device must be awake to reliably request remote wakeup */
if (res < 0) {
hid->open--;
res = -EIO;
goto done;
}
usbhid->intf->needs_remote_wakeup = 1;
set_bit(HID_OPENED, &usbhid->iofl);
set_bit(HID_IN_POLLING, &usbhid->iofl);
set_bit(HID_RESUME_RUNNING, &usbhid->iofl);
res = hid_start_in(hid);
if (res) {
if (res != -ENOSPC) {
hid_io_error(hid);
res = 0;
} else {
/* no use opening if resources are insufficient */
hid->open--;
clear_bit(HID_OPENED, &usbhid->iofl);
if (!(hid->quirks & HID_QUIRK_ALWAYS_POLL))
clear_bit(HID_IN_POLLING, &usbhid->iofl);
res = -EBUSY;
usbhid->intf->needs_remote_wakeup = 0;
}
}
usb_autopm_put_interface(usbhid->intf);
if (hid->quirks & HID_QUIRK_ALWAYS_POLL)
return 0;
/*
* In case events are generated while nobody was listening,
* some are released when the device is re-opened.
* Wait 50 msec for the queue to empty before allowing events
* to go through hid.
*/
if (res == 0 && !(hid->quirks & HID_QUIRK_ALWAYS_POLL))
msleep(50);
clear_bit(HID_RESUME_RUNNING, &usbhid->iofl);
res = usb_autopm_get_interface(usbhid->intf);
/* the device must be awake to reliably request remote wakeup */
if (res < 0)
return -EIO;
usbhid->intf->needs_remote_wakeup = 1;
set_bit(HID_RESUME_RUNNING, &usbhid->iofl);
set_bit(HID_OPENED, &usbhid->iofl);
set_bit(HID_IN_POLLING, &usbhid->iofl);
res = hid_start_in(hid);
if (res) {
if (res != -ENOSPC) {
hid_io_error(hid);
res = 0;
} else {
/* no use opening if resources are insufficient */
res = -EBUSY;
clear_bit(HID_OPENED, &usbhid->iofl);
clear_bit(HID_IN_POLLING, &usbhid->iofl);
usbhid->intf->needs_remote_wakeup = 0;
}
}
done:
mutex_unlock(&hid_open_mut);
usb_autopm_put_interface(usbhid->intf);
/*
* In case events are generated while nobody was listening,
* some are released when the device is re-opened.
* Wait 50 msec for the queue to empty before allowing events
* to go through hid.
*/
if (res == 0)
msleep(50);
clear_bit(HID_RESUME_RUNNING, &usbhid->iofl);
return res;
}
@ -731,27 +727,22 @@ static void usbhid_close(struct hid_device *hid)
{
struct usbhid_device *usbhid = hid->driver_data;
mutex_lock(&hid_open_mut);
if (hid->quirks & HID_QUIRK_ALWAYS_POLL)
return;
/* protecting hid->open to make sure we don't restart
* data acquistion due to a resumption we no longer
* care about
/*
* Make sure we don't restart data acquisition due to
* a resumption we no longer care about by avoiding racing
* with hid_start_in().
*/
spin_lock_irq(&usbhid->lock);
if (!--hid->open) {
if (!(hid->quirks & HID_QUIRK_ALWAYS_POLL))
clear_bit(HID_IN_POLLING, &usbhid->iofl);
clear_bit(HID_OPENED, &usbhid->iofl);
spin_unlock_irq(&usbhid->lock);
hid_cancel_delayed_stuff(usbhid);
if (!(hid->quirks & HID_QUIRK_ALWAYS_POLL)) {
usb_kill_urb(usbhid->urbin);
usbhid->intf->needs_remote_wakeup = 0;
}
} else {
spin_unlock_irq(&usbhid->lock);
}
mutex_unlock(&hid_open_mut);
clear_bit(HID_IN_POLLING, &usbhid->iofl);
clear_bit(HID_OPENED, &usbhid->iofl);
spin_unlock_irq(&usbhid->lock);
hid_cancel_delayed_stuff(usbhid);
usb_kill_urb(usbhid->urbin);
usbhid->intf->needs_remote_wakeup = 0;
}
/*