| Message ID | 20180228133803.30040-6-marcus.folkesson@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Wed, Feb 28, 2018 at 02:38:02PM +0100, Marcus Folkesson wrote: > 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 <marcus.folkesson@gmail.com> Applied, thank you. > --- > 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 2c41107240de..e964658203d8 100644 > --- a/drivers/input/touchscreen/usbtouchscreen.c > +++ b/drivers/input/touchscreen/usbtouchscreen.c > @@ -54,6 +54,7 @@ > #include <linux/usb.h> > #include <linux/usb/input.h> > #include <linux/hid.h> > +#include <linux/mutex.h> > > > #define DRIVER_VERSION "v0.6" > @@ -112,6 +113,7 @@ 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; > @@ -1455,6 +1457,7 @@ 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; > @@ -1464,6 +1467,7 @@ 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; > @@ -1474,8 +1478,11 @@ 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_lock(&usbtouch->pm_mutex); > + > r = usb_autopm_get_interface(usbtouch->interface); > usbtouch->interface->needs_remote_wakeup = 0; > if (!r) > @@ -1498,10 +1505,10 @@ 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; > } > @@ -1524,10 +1531,10 @@ 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; > } > -- > 2.16.2 >
diff --git a/drivers/input/touchscreen/usbtouchscreen.c b/drivers/input/touchscreen/usbtouchscreen.c index 2c41107240de..e964658203d8 100644 --- a/drivers/input/touchscreen/usbtouchscreen.c +++ b/drivers/input/touchscreen/usbtouchscreen.c @@ -54,6 +54,7 @@ #include <linux/usb.h> #include <linux/usb/input.h> #include <linux/hid.h> +#include <linux/mutex.h> #define DRIVER_VERSION "v0.6" @@ -112,6 +113,7 @@ 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; @@ -1455,6 +1457,7 @@ 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; @@ -1464,6 +1467,7 @@ 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; @@ -1474,8 +1478,11 @@ 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_lock(&usbtouch->pm_mutex); + r = usb_autopm_get_interface(usbtouch->interface); usbtouch->interface->needs_remote_wakeup = 0; if (!r) @@ -1498,10 +1505,10 @@ 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; } @@ -1524,10 +1531,10 @@ 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; }
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 <marcus.folkesson@gmail.com> --- drivers/input/touchscreen/usbtouchscreen.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-)