Commit 5a6a62bd authored by Oliver Neukum's avatar Oliver Neukum Committed by Greg Kroah-Hartman
Browse files

cdc-acm: add TIOCMIWAIT 



This implements TIOCMIWAIT for TIOCM_DSR, TIOCM_RI and TIOCM_CD
Disconnect is handled as TIOCM_CD or an error.

Signed-off-by: default avatarOliver Neukum <oneukum@suse.de>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 4e065b8b

drivers/usb/class/cdc-acm.c

+74 −12
Original line number Diff line number Diff line
@@ -262,6 +262,7 @@ static void acm_ctrl_irq(struct urb *urb) 
	struct usb_cdc_notification *dr = urb->transfer_buffer;

	unsigned char *data;

	int newctrl;

	int difference;

	int retval;

	int status = urb->status;
@@ -302,19 +303,30 @@ static void acm_ctrl_irq(struct urb *urb) 
			tty_port_tty_hangup(&acm->port, false);

		}



		difference = acm->ctrlin ^ newctrl;

		spin_lock(&acm->read_lock);

		acm->ctrlin = newctrl;

		acm->oldcount = acm->iocount;



		if (difference & ACM_CTRL_DSR)

			acm->iocount.dsr++;

		if (difference & ACM_CTRL_BRK)

			acm->iocount.brk++;

		if (difference & ACM_CTRL_RI)

			acm->iocount.rng++;

		if (difference & ACM_CTRL_DCD)

			acm->iocount.dcd++;

		if (difference & ACM_CTRL_FRAMING)

			acm->iocount.frame++;

		if (difference & ACM_CTRL_PARITY)

			acm->iocount.parity++;

		if (difference & ACM_CTRL_OVERRUN)

			acm->iocount.overrun++;

		spin_unlock(&acm->read_lock);



		if (difference)

			wake_up_all(&acm->wioctl);



		dev_dbg(&acm->control->dev,

			"%s - input control lines: dcd%c dsr%c break%c "

			"ring%c framing%c parity%c overrun%c\n",

			__func__,

			acm->ctrlin & ACM_CTRL_DCD ? '+' : '-',

			acm->ctrlin & ACM_CTRL_DSR ? '+' : '-',

			acm->ctrlin & ACM_CTRL_BRK ? '+' : '-',

			acm->ctrlin & ACM_CTRL_RI  ? '+' : '-',

			acm->ctrlin & ACM_CTRL_FRAMING ? '+' : '-',

			acm->ctrlin & ACM_CTRL_PARITY ? '+' : '-',

			acm->ctrlin & ACM_CTRL_OVERRUN ? '+' : '-');

		break;



	default:
@@ -796,6 +808,51 @@ static int set_serial_info(struct acm *acm, 
	return retval;

}



static int wait_serial_change(struct acm *acm, unsigned long arg)

{

	int rv = 0;

	DECLARE_WAITQUEUE(wait, current);

	struct async_icount old, new;



	if (arg & (TIOCM_DSR | TIOCM_RI | TIOCM_CD ))

		return -EINVAL;

	do {

		spin_lock_irq(&acm->read_lock);

		old = acm->oldcount;

		new = acm->iocount;

		acm->oldcount = new;

		spin_unlock_irq(&acm->read_lock);



		if ((arg & TIOCM_DSR) &&

			old.dsr != new.dsr)

			break;

		if ((arg & TIOCM_CD)  &&

			old.dcd != new.dcd)

			break;

		if ((arg & TIOCM_RI) &&

			old.rng != new.rng)

			break;



		add_wait_queue(&acm->wioctl, &wait);

		set_current_state(TASK_INTERRUPTIBLE);

		schedule();

		remove_wait_queue(&acm->wioctl, &wait);

		if (acm->disconnected) {

			if (arg & TIOCM_CD)

				break;

			else

				rv = -ENODEV;

		} else {

			if (signal_pending(current))

				rv = -ERESTARTSYS;

		}

	} while (!rv);



	



	return rv;

}



static int acm_tty_ioctl(struct tty_struct *tty,

					unsigned int cmd, unsigned long arg)

{
@@ -809,6 +866,9 @@ static int acm_tty_ioctl(struct tty_struct *tty, 
	case TIOCSSERIAL:

		rv = set_serial_info(acm, (struct serial_struct __user *) arg);

		break;

	case TIOCMIWAIT:

		rv = wait_serial_change(acm, arg);

		break;

	}



	return rv;
@@ -1167,6 +1227,7 @@ static int acm_probe(struct usb_interface *intf, 
	acm->readsize = readsize;

	acm->rx_buflimit = num_rx_buf;

	INIT_WORK(&acm->work, acm_softint);

	init_waitqueue_head(&acm->wioctl);

	spin_lock_init(&acm->write_lock);

	spin_lock_init(&acm->read_lock);

	mutex_init(&acm->mutex);
@@ -1383,6 +1444,7 @@ static void acm_disconnect(struct usb_interface *intf) 
		device_remove_file(&acm->control->dev,

				&dev_attr_iCountryCodeRelDate);

	}

	wake_up_all(&acm->wioctl);

	device_remove_file(&acm->control->dev, &dev_attr_bmCapabilities);

	usb_set_intfdata(acm->control, NULL);

	usb_set_intfdata(acm->data, NULL);

drivers/usb/class/cdc-acm.h

+3 −0
Original line number Diff line number Diff line
@@ -106,6 +106,9 @@ struct acm { 
	struct work_struct work;			/* work queue entry for line discipline waking up */

	unsigned int ctrlin;				/* input control lines (DCD, DSR, RI, break, overruns) */

	unsigned int ctrlout;				/* output control lines (DTR, RTS) */

	struct async_icount iocount;			/* counters for control line changes */

	struct async_icount oldcount;			/* for comparison of counter */

	wait_queue_head_t wioctl;			/* for ioctl */

	unsigned int writesize;				/* max packet size for the output bulk endpoint */

	unsigned int readsize,ctrlsize;			/* buffer sizes for freeing */

	unsigned int minor;				/* acm minor number */