/* destroy an USB endpoint */
void fhci_ep0_free(struct fhci_usb *usb)
{
struct endpoint *ep;
int size;
ep = usb->ep0;
if (ep) {
if (ep->td_base)
cpm_muram_free(cpm_muram_offset(ep->td_base));
if (kfifo_initialized(&ep->conf_frame_Q)) {
size = cq_howmany(&ep->conf_frame_Q);
for (; size; size--) {
struct packet *pkt = cq_get(&ep->conf_frame_Q);
kfree(pkt);
}
cq_delete(&ep->conf_frame_Q);
}
if (kfifo_initialized(&ep->empty_frame_Q)) {
size = cq_howmany(&ep->empty_frame_Q);
for (; size; size--) {
struct packet *pkt = cq_get(&ep->empty_frame_Q);
kfree(pkt);
}
cq_delete(&ep->empty_frame_Q);
}
if (kfifo_initialized(&ep->dummy_packets_Q)) {
size = cq_howmany(&ep->dummy_packets_Q);
for (; size; size--) {
u8 *buff = cq_get(&ep->dummy_packets_Q);
kfree(buff);
}
cq_delete(&ep->dummy_packets_Q);
}
kfree(ep);
usb->ep0 = NULL;
}
}
static int iio_kfifo_write(struct iio_buffer *r, size_t n,
const char __user *buf)
{
struct iio_kfifo *kf = iio_to_kfifo(r);
int ret, copied;
mutex_lock(&kf->user_lock);
if (!kfifo_initialized(&kf->kf) || n < kfifo_esize(&kf->kf))
ret = -EINVAL;
else
ret = kfifo_from_user(&kf->kf, buf, n, &copied);
mutex_unlock(&kf->user_lock);
if (ret)
return ret;
return copied;
}
static int iio_read_kfifo(struct iio_buffer *r, size_t n, char __user *buf)
{
int ret, copied;
struct iio_kfifo *kf = iio_to_kfifo(r);
if (mutex_lock_interruptible(&kf->user_lock))
return -ERESTARTSYS;
if (!kfifo_initialized(&kf->kf) || n < kfifo_esize(&kf->kf))
ret = -EINVAL;
else
ret = kfifo_to_user(&kf->kf, buf, n, &copied);
mutex_unlock(&kf->user_lock);
if (ret < 0)
return ret;
return copied;
}
/*
* gs_open sets up the link between a gs_port and its associated TTY.
* That link is broken *only* by TTY close(), and all driver methods
* know that.
*/
static int gs_open(struct tty_struct *tty, struct file *file)
{
int port_num = tty->index;
struct gs_port *port;
int status;
do {
mutex_lock(&ports[port_num].lock);
port = ports[port_num].port;
if (!port)
status = -ENODEV;
else {
spin_lock_irq(&port->port_lock);
/* already open? Great. */
if (port->port.count) {
status = 0;
port->port.count++;
/* currently opening/closing? wait ... */
} else if (port->openclose) {
status = -EBUSY;
/* ... else we do the work */
} else {
status = -EAGAIN;
port->openclose = true;
}
spin_unlock_irq(&port->port_lock);
}
mutex_unlock(&ports[port_num].lock);
switch (status) {
default:
/* fully handled */
return status;
case -EAGAIN:
/* must do the work */
break;
case -EBUSY:
/* wait for EAGAIN task to finish */
msleep(1);
/* REVISIT could have a waitchannel here, if
* concurrent open performance is important
*/
break;
}
} while (status != -EAGAIN);
/* Do the "real open" */
spin_lock_irq(&port->port_lock);
/* allocate circular buffer on first open */
if (!kfifo_initialized(&port->port_write_buf)) {
spin_unlock_irq(&port->port_lock);
status = kfifo_alloc(&port->port_write_buf,
WRITE_BUF_SIZE, GFP_KERNEL);
spin_lock_irq(&port->port_lock);
if (status) {
pr_debug("gs_open: ttyGS%d (%p,%p) no buffer\n",
port->port_num, tty, file);
port->openclose = false;
goto exit_unlock_port;
}
}
/* REVISIT if REMOVED (ports[].port NULL), abort the open
* to let rmmod work faster (but this way isn't wrong).
*/
/* REVISIT maybe wait for "carrier detect" */
tty->driver_data = port;
port->port.tty = tty;
port->port.count = 1;
port->openclose = false;
/* if connected, start the I/O stream */
if (port->port_usb) {
struct gserial *gser = port->port_usb;
pr_debug("gs_open: start ttyGS%d\n", port->port_num);
gs_start_io(port);
if (gser->connect)
gser->connect(gser);
}
pr_debug("gs_open: ttyGS%d (%p,%p)\n", port->port_num, tty, file);
status = 0;
exit_unlock_port:
spin_unlock_irq(&port->port_lock);
return status;
}
