From 12e510dbc57b29b4314cd792851532bea76b4715 Mon Sep 17 00:00:00 2001 From: Marcus Folkesson Date: Sat, 17 Mar 2018 10:52:39 -0700 Subject: [PATCH] Input: usbtouchscreen - fix deadlock in autosuspend usb_autopm_get_interface() that is called in usbtouch_open() does an autoresume if the device is suspended. input_dev->mutex used in usbtouch_resume() is in this case already taken by the input subsystem and will cause a deadlock. Signed-off-by: Marcus Folkesson Signed-off-by: Dmitry Torokhov --- drivers/input/touchscreen/usbtouchscreen.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/drivers/input/touchscreen/usbtouchscreen.c b/drivers/input/touchscreen/usbtouchscreen.c index aa77d243b786..d15a7e2d9bbf 100644 --- a/drivers/input/touchscreen/usbtouchscreen.c +++ b/drivers/input/touchscreen/usbtouchscreen.c @@ -54,6 +54,7 @@ #include #include #include +#include static bool swap_xy; module_param(swap_xy, bool, 0644); @@ -107,6 +108,7 @@ struct usbtouch_usb { struct usb_interface *interface; struct input_dev *input; struct usbtouch_device_info *type; + struct mutex pm_mutex; /* serialize access to open/suspend */ char name[128]; char phys[64]; void *priv; @@ -1450,6 +1452,7 @@ static int usbtouch_open(struct input_dev *input) if (r < 0) goto out; + mutex_lock(&usbtouch->pm_mutex); if (!usbtouch->type->irq_always) { if (usb_submit_urb(usbtouch->irq, GFP_KERNEL)) { r = -EIO; @@ -1459,6 +1462,7 @@ static int usbtouch_open(struct input_dev *input) usbtouch->interface->needs_remote_wakeup = 1; out_put: + mutex_unlock(&usbtouch->pm_mutex); usb_autopm_put_interface(usbtouch->interface); out: return r; @@ -1469,8 +1473,11 @@ static void usbtouch_close(struct input_dev *input) struct usbtouch_usb *usbtouch = input_get_drvdata(input); int r; + mutex_lock(&usbtouch->pm_mutex); if (!usbtouch->type->irq_always) usb_kill_urb(usbtouch->irq); + mutex_unlock(&usbtouch->pm_mutex); + r = usb_autopm_get_interface(usbtouch->interface); usbtouch->interface->needs_remote_wakeup = 0; if (!r) @@ -1493,10 +1500,10 @@ static int usbtouch_resume(struct usb_interface *intf) struct input_dev *input = usbtouch->input; int result = 0; - mutex_lock(&input->mutex); + mutex_lock(&usbtouch->pm_mutex); if (input->users || usbtouch->type->irq_always) result = usb_submit_urb(usbtouch->irq, GFP_NOIO); - mutex_unlock(&input->mutex); + mutex_unlock(&usbtouch->pm_mutex); return result; } @@ -1519,10 +1526,10 @@ static int usbtouch_reset_resume(struct usb_interface *intf) } /* restart IO if needed */ - mutex_lock(&input->mutex); + mutex_lock(&usbtouch->pm_mutex); if (input->users) err = usb_submit_urb(usbtouch->irq, GFP_NOIO); - mutex_unlock(&input->mutex); + mutex_unlock(&usbtouch->pm_mutex); return err; }