USB: mos7840: remove smp barriers from icount handling (c9fac853) · Commits · e / devices / android_kernel_fairphone_FP3

drivers/usb/serial/mos7840.c

+19 −29

Original line number	Original line	Diff line number	Diff line
	@@ -406,22 +406,14 @@ static void mos7840_handle_new_msr(struct moschip_port *port, __u8 new_msr)
	icount = &mos7840_port->icount;		icount = &mos7840_port->icount;

	/* update input line counters */		/* update input line counters */
	if (new_msr & MOS_MSR_DELTA_CTS) {		if (new_msr & MOS_MSR_DELTA_CTS)
	icount->cts++;		icount->cts++;
	smp_wmb();		if (new_msr & MOS_MSR_DELTA_DSR)
	}
	if (new_msr & MOS_MSR_DELTA_DSR) {
	icount->dsr++;		icount->dsr++;
	smp_wmb();		if (new_msr & MOS_MSR_DELTA_CD)
	}
	if (new_msr & MOS_MSR_DELTA_CD) {
	icount->dcd++;		icount->dcd++;
	smp_wmb();		if (new_msr & MOS_MSR_DELTA_RI)
	}
	if (new_msr & MOS_MSR_DELTA_RI) {
	icount->rng++;		icount->rng++;
	smp_wmb();
	}

	mos7840_port->delta_msr_cond = 1;		mos7840_port->delta_msr_cond = 1;
	wake_up_interruptible(&port->port->delta_msr_wait);		wake_up_interruptible(&port->port->delta_msr_wait);
	@@ -443,22 +435,14 @@ static void mos7840_handle_new_lsr(struct moschip_port *port, __u8 new_lsr)

	/* update input line counters */		/* update input line counters */
	icount = &port->icount;		icount = &port->icount;
	if (new_lsr & SERIAL_LSR_BI) {		if (new_lsr & SERIAL_LSR_BI)
	icount->brk++;		icount->brk++;
	smp_wmb();		if (new_lsr & SERIAL_LSR_OE)
	}
	if (new_lsr & SERIAL_LSR_OE) {
	icount->overrun++;		icount->overrun++;
	smp_wmb();		if (new_lsr & SERIAL_LSR_PE)
	}
	if (new_lsr & SERIAL_LSR_PE) {
	icount->parity++;		icount->parity++;
	smp_wmb();		if (new_lsr & SERIAL_LSR_FE)
	}
	if (new_lsr & SERIAL_LSR_FE) {
	icount->frame++;		icount->frame++;
	smp_wmb();
	}
	}		}

	/************************************************************************/		/************************************************************************/
	@@ -778,7 +762,6 @@ static void mos7840_bulk_in_callback(struct urb *urb)
	tty_insert_flip_string(tport, data, urb->actual_length);		tty_insert_flip_string(tport, data, urb->actual_length);
	tty_flip_buffer_push(tport);		tty_flip_buffer_push(tport);
	mos7840_port->icount.rx += urb->actual_length;		mos7840_port->icount.rx += urb->actual_length;
	smp_wmb();
	dev_dbg(&port->dev, "mos7840_port->icount.rx is %d:\n", mos7840_port->icount.rx);		dev_dbg(&port->dev, "mos7840_port->icount.rx is %d:\n", mos7840_port->icount.rx);
	}		}

	@@ -1507,7 +1490,6 @@ static int mos7840_write(struct tty_struct tty, struct usb_serial_port port,
	}		}
	bytes_sent = transfer_size;		bytes_sent = transfer_size;
	mos7840_port->icount.tx += transfer_size;		mos7840_port->icount.tx += transfer_size;
	smp_wmb();
	dev_dbg(&port->dev, "mos7840_port->icount.tx is %d:\n", mos7840_port->icount.tx);		dev_dbg(&port->dev, "mos7840_port->icount.tx is %d:\n", mos7840_port->icount.tx);
	exit:		exit:
	return bytes_sent;		return bytes_sent;
	@@ -2133,11 +2115,14 @@ static int mos7840_get_icount(struct tty_struct *tty,
	struct usb_serial_port *port = tty->driver_data;		struct usb_serial_port *port = tty->driver_data;
	struct moschip_port *mos7840_port;		struct moschip_port *mos7840_port;
	struct async_icount cnow;		struct async_icount cnow;
			unsigned long flags;

	mos7840_port = mos7840_get_port_private(port);		mos7840_port = mos7840_get_port_private(port);

			spin_lock_irqsave(&port->lock, flags);
	cnow = mos7840_port->icount;		cnow = mos7840_port->icount;
			spin_unlock_irqrestore(&port->lock, flags);

	smp_rmb();
	icount->cts = cnow.cts;		icount->cts = cnow.cts;
	icount->dsr = cnow.dsr;		icount->dsr = cnow.dsr;
	icount->rng = cnow.rng;		icount->rng = cnow.rng;
	@@ -2166,7 +2151,7 @@ static int mos7840_ioctl(struct tty_struct *tty,
	struct usb_serial_port *port = tty->driver_data;		struct usb_serial_port *port = tty->driver_data;
	void __user argp = (void __user )arg;		void __user argp = (void __user )arg;
	struct moschip_port *mos7840_port;		struct moschip_port *mos7840_port;
			unsigned long flags;
	struct async_icount cnow;		struct async_icount cnow;
	struct async_icount cprev;		struct async_icount cprev;

	@@ -2197,7 +2182,9 @@ static int mos7840_ioctl(struct tty_struct *tty,

	case TIOCMIWAIT:		case TIOCMIWAIT:
	dev_dbg(&port->dev, "%s TIOCMIWAIT\n", __func__);		dev_dbg(&port->dev, "%s TIOCMIWAIT\n", __func__);
			spin_lock_irqsave(&port->lock, flags);
	cprev = mos7840_port->icount;		cprev = mos7840_port->icount;
			spin_unlock_irqrestore(&port->lock, flags);
	while (1) {		while (1) {
	/* interruptible_sleep_on(&mos7840_port->delta_msr_wait); */		/* interruptible_sleep_on(&mos7840_port->delta_msr_wait); */
	mos7840_port->delta_msr_cond = 0;		mos7840_port->delta_msr_cond = 0;
	@@ -2213,11 +2200,14 @@ static int mos7840_ioctl(struct tty_struct *tty,
	if (port->serial->disconnected)		if (port->serial->disconnected)
	return -EIO;		return -EIO;

			spin_lock_irqsave(&port->lock, flags);
	cnow = mos7840_port->icount;		cnow = mos7840_port->icount;
	smp_rmb();		spin_unlock_irqrestore(&port->lock, flags);

	if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&		if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
	cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)		cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
	return -EIO; /* no change => error */		return -EIO; /* no change => error */

	if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) \|\|		if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) \|\|
	((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) \|\|		((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) \|\|
	((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) \|\|		((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) \|\|