diff options
Diffstat (limited to 'drivers/usb/gadget/function/u_serial.c')
| -rw-r--r-- | drivers/usb/gadget/function/u_serial.c | 35 |
1 files changed, 14 insertions, 21 deletions
diff --git a/drivers/usb/gadget/function/u_serial.c b/drivers/usb/gadget/function/u_serial.c index 29436f75bbe0..65f634ec7fc2 100644 --- a/drivers/usb/gadget/function/u_serial.c +++ b/drivers/usb/gadget/function/u_serial.c @@ -16,7 +16,6 @@ #include <linux/kernel.h> #include <linux/sched.h> -#include <linux/interrupt.h> #include <linux/device.h> #include <linux/delay.h> #include <linux/tty.h> @@ -26,6 +25,7 @@ #include <linux/module.h> #include <linux/console.h> #include <linux/kthread.h> +#include <linux/workqueue.h> #include <linux/kfifo.h> #include "u_serial.h" @@ -110,7 +110,7 @@ struct gs_port { int read_allocated; struct list_head read_queue; unsigned n_read; - struct tasklet_struct push; + struct delayed_work push; struct list_head write_pool; int write_started; @@ -352,9 +352,10 @@ __acquires(&port->port_lock) * So QUEUE_SIZE packets plus however many the FIFO holds (usually two) * can be buffered before the TTY layer's buffers (currently 64 KB). */ -static void gs_rx_push(unsigned long _port) +static void gs_rx_push(struct work_struct *work) { - struct gs_port *port = (void *)_port; + struct delayed_work *w = to_delayed_work(work); + struct gs_port *port = container_of(w, struct gs_port, push); struct tty_struct *tty; struct list_head *queue = &port->read_queue; bool disconnect = false; @@ -429,21 +430,13 @@ static void gs_rx_push(unsigned long _port) /* We want our data queue to become empty ASAP, keeping data * in the tty and ldisc (not here). If we couldn't push any - * this time around, there may be trouble unless there's an - * implicit tty_unthrottle() call on its way... + * this time around, RX may be starved, so wait until next jiffy. * - * REVISIT we should probably add a timer to keep the tasklet - * from starving ... but it's not clear that case ever happens. + * We may leave non-empty queue only when there is a tty, and + * either it is throttled or there is no more room in flip buffer. */ - if (!list_empty(queue) && tty) { - if (!tty_throttled(tty)) { - if (do_push) - tasklet_schedule(&port->push); - else - pr_warn("ttyGS%d: RX not scheduled?\n", - port->port_num); - } - } + if (!list_empty(queue) && !tty_throttled(tty)) + schedule_delayed_work(&port->push, 1); /* If we're still connected, refill the USB RX queue. */ if (!disconnect && port->port_usb) @@ -459,7 +452,7 @@ static void gs_read_complete(struct usb_ep *ep, struct usb_request *req) /* Queue all received data until the tty layer is ready for it. */ spin_lock(&port->port_lock); list_add_tail(&req->list, &port->read_queue); - tasklet_schedule(&port->push); + schedule_delayed_work(&port->push, 0); spin_unlock(&port->port_lock); } @@ -854,8 +847,8 @@ static void gs_unthrottle(struct tty_struct *tty) * rts/cts, or other handshaking with the host, but if the * read queue backs up enough we'll be NAKing OUT packets. */ - tasklet_schedule(&port->push); pr_vdebug("ttyGS%d: unthrottle\n", port->port_num); + schedule_delayed_work(&port->push, 0); } spin_unlock_irqrestore(&port->port_lock, flags); } @@ -1159,7 +1152,7 @@ gs_port_alloc(unsigned port_num, struct usb_cdc_line_coding *coding) init_waitqueue_head(&port->drain_wait); init_waitqueue_head(&port->close_wait); - tasklet_init(&port->push, gs_rx_push, (unsigned long) port); + INIT_DELAYED_WORK(&port->push, gs_rx_push); INIT_LIST_HEAD(&port->read_pool); INIT_LIST_HEAD(&port->read_queue); @@ -1186,7 +1179,7 @@ static int gs_closed(struct gs_port *port) static void gserial_free_port(struct gs_port *port) { - tasklet_kill(&port->push); + cancel_delayed_work_sync(&port->push); /* wait for old opens to finish */ wait_event(port->close_wait, gs_closed(port)); WARN_ON(port->port_usb != NULL); |