diff --git a/drivers/usb/gadget/function/f_midi.c b/drivers/usb/gadget/function/f_midi.c index 84c0ee5ebd1e..56e2dde99b03 100644 --- a/drivers/usb/gadget/function/f_midi.c +++ b/drivers/usb/gadget/function/f_midi.c @@ -24,6 +24,7 @@ #include #include #include +#include #include #include @@ -89,6 +90,7 @@ struct f_midi { unsigned int buflen, qlen; /* This fifo is used as a buffer ring for pre-allocated IN usb_requests */ DECLARE_KFIFO_PTR(in_req_fifo, struct usb_request *); + spinlock_t transmit_lock; unsigned int in_last_port; struct gmidi_in_port in_ports_array[/* in_ports */]; @@ -597,17 +599,22 @@ static void f_midi_transmit(struct f_midi *midi) { struct usb_ep *ep = midi->in_ep; int ret; + unsigned long flags; /* We only care about USB requests if IN endpoint is enabled */ if (!ep || !ep->enabled) goto drop_out; + spin_lock_irqsave(&midi->transmit_lock, flags); + do { ret = f_midi_do_transmit(midi, ep); if (ret < 0) goto drop_out; } while (ret); + spin_unlock_irqrestore(&midi->transmit_lock, flags); + return; drop_out: @@ -1201,6 +1208,8 @@ static struct usb_function *f_midi_alloc(struct usb_function_instance *fi) if (status) goto setup_fail; + spin_lock_init(&midi->transmit_lock); + ++opts->refcnt; mutex_unlock(&opts->lock);