Merge tag 'tty-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here is the big set of tty/serial driver changes for 5.12-rc1.

  Nothing huge, just lots of good cleanups and additions:

   - n_tty line discipline cleanups

   - vt core cleanups and reworks to make the code more "modern"

   - stm32 driver additions

   - tty led support added to the tty core and led layer

   - minor serial driver fixups and additions

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (54 commits)
  serial: core: Remove BUG_ON(in_interrupt()) check
  vt_ioctl: Remove in_interrupt() check
  dt-bindings: serial: imx: Switch to my personal address
  vt: keyboard, use new API for keyboard_tasklet
  serial: stm32: improve platform_get_irq condition handling in init_port
  serial: ifx6x60: Remove driver for deprecated platform
  tty: fix up iterate_tty_read() EOVERFLOW handling
  tty: fix up hung_up_tty_read() conversion
  tty: fix up hung_up_tty_write() conversion
  tty: teach the n_tty ICANON case about the new "cookie continuations" too
  tty: teach n_tty line discipline about the new "cookie continuations"
  tty: clean up legacy leftovers from n_tty line discipline
  tty: implement read_iter
  tty: convert tty_ldisc_ops 'read()' function to take a kernel pointer
  serial: remove sirf prima/atlas driver
  serial: mxs-auart: Remove <asm/cacheflush.h>
  serial: mxs-auart: Remove serial_mxs_probe_dt()
  serial: fsl_lpuart: Use of_device_get_match_data()
  dt-bindings: serial: renesas,hscif: Add r8a779a0 support
  tty: serial: Drop unused efm32 serial driver
  ...

38 files changed, 710 insertions, 5009 deletions

diff --git a/drivers/tty/amiserial.c b/drivers/tty/amiserial.c
index 13f63c01c589..18b78ea110ef 100644
--- a/drivers/tty/amiserial.c
+++ b/drivers/tty/amiserial.c
@@ -998,7 +998,6 @@ static int set_serial_info(struct tty_struct *tty, struct serial_struct *ss)
 	state->custom_divisor = ss->custom_divisor;
 	port->close_delay = ss->close_delay * HZ/100;
 	port->closing_wait = ss->closing_wait * HZ/100;
-	port->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 
 check_and_exit:
 	if (tty_port_initialized(port)) {
@@ -1386,8 +1385,6 @@ static int rs_open(struct tty_struct *tty, struct file * filp)
 	tty->driver_data = info;
 	tty->port = port;
 
-	port->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
-
 	retval = startup(tty, info);
 	if (retval) {
 		return retval;
diff --git a/drivers/tty/hvc/hvcs.c b/drivers/tty/hvc/hvcs.c
index 509d1042825a..c90848919644 100644
--- a/drivers/tty/hvc/hvcs.c
+++ b/drivers/tty/hvc/hvcs.c
@@ -605,7 +605,7 @@ static int hvcs_io(struct hvcs_struct *hvcsd)
 		hvcsd->todo_mask |= HVCS_QUICK_READ;
 
 	spin_unlock_irqrestore(&hvcsd->lock, flags);
-	/* This is synch because tty->low_latency == 1 */
+	/* This is synch -- FIXME :js: it is not! */
 	if(got)
 		tty_flip_buffer_push(&hvcsd->port);
 
@@ -825,9 +825,6 @@ static int hvcs_remove(struct vio_dev *dev)
 	unsigned long flags;
 	struct tty_struct *tty;
 
-	if (!hvcsd)
-		return -ENODEV;
-
 	/* By this time the vty-server won't be getting any more interrupts */
 
 	spin_lock_irqsave(&hvcsd->lock, flags);
diff --git a/drivers/tty/ipwireless/tty.c b/drivers/tty/ipwireless/tty.c
index 23584769fc29..6dacbc5e286c 100644
--- a/drivers/tty/ipwireless/tty.c
+++ b/drivers/tty/ipwireless/tty.c
@@ -101,7 +101,6 @@ static int ipw_open(struct tty_struct *linux_tty, struct file *filp)
 
 	tty->port.tty = linux_tty;
 	linux_tty->driver_data = tty;
-	tty->port.low_latency = 1;
 
 	if (tty->tty_type == TTYTYPE_MODEM)
 		ipwireless_ppp_open(tty->network);
diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c
index 3703987c4666..4203b64bccdb 100644
--- a/drivers/tty/mxser.c
+++ b/drivers/tty/mxser.c
@@ -1273,7 +1273,6 @@ static int mxser_set_serial_info(struct tty_struct *tty,
 				(ss->flags & ASYNC_FLAGS));
 		port->close_delay = ss->close_delay * HZ / 100;
 		port->closing_wait = ss->closing_wait * HZ / 100;
-		port->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 		if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST &&
 				(ss->baud_base != info->baud_base ||
 				ss->custom_divisor !=
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index c676fa89ee0b..51dafc06f541 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -2559,7 +2559,8 @@ static void gsmld_write_wakeup(struct tty_struct *tty)
  */
 
 static ssize_t gsmld_read(struct tty_struct *tty, struct file *file,
-			 unsigned char __user *buf, size_t nr)
+			  unsigned char *buf, size_t nr,
+			  void **cookie, unsigned long offset)
 {
 	return -EOPNOTSUPP;
 }
diff --git a/drivers/tty/n_hdlc.c b/drivers/tty/n_hdlc.c
index 12557ee1edb6..1363e659dc1d 100644
--- a/drivers/tty/n_hdlc.c
+++ b/drivers/tty/n_hdlc.c
@@ -416,13 +416,19 @@ static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *data,
  * Returns the number of bytes returned or error code.
  */
 static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file,
-			   __u8 __user *buf, size_t nr)
+			   __u8 *kbuf, size_t nr,
+			   void **cookie, unsigned long offset)
 {
 	struct n_hdlc *n_hdlc = tty->disc_data;
 	int ret = 0;
 	struct n_hdlc_buf *rbuf;
 	DECLARE_WAITQUEUE(wait, current);
 
+	/* Is this a repeated call for an rbuf we already found earlier? */
+	rbuf = *cookie;
+	if (rbuf)
+		goto have_rbuf;
+
 	add_wait_queue(&tty->read_wait, &wait);
 
 	for (;;) {
@@ -436,25 +442,8 @@ static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file,
 		set_current_state(TASK_INTERRUPTIBLE);
 
 		rbuf = n_hdlc_buf_get(&n_hdlc->rx_buf_list);
-		if (rbuf) {
-			if (rbuf->count > nr) {
-				/* too large for caller's buffer */
-				ret = -EOVERFLOW;
-			} else {
-				__set_current_state(TASK_RUNNING);
-				if (copy_to_user(buf, rbuf->buf, rbuf->count))
-					ret = -EFAULT;
-				else
-					ret = rbuf->count;
-			}
-
-			if (n_hdlc->rx_free_buf_list.count >
-			    DEFAULT_RX_BUF_COUNT)
-				kfree(rbuf);
-			else
-				n_hdlc_buf_put(&n_hdlc->rx_free_buf_list, rbuf);
+		if (rbuf)
 			break;
-		}
 
 		/* no data */
 		if (tty_io_nonblock(tty, file)) {
@@ -473,6 +462,39 @@ static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file,
 	remove_wait_queue(&tty->read_wait, &wait);
 	__set_current_state(TASK_RUNNING);
 
+	if (!rbuf)
+		return ret;
+	*cookie = rbuf;
+
+have_rbuf:
+	/* Have we used it up entirely? */
+	if (offset >= rbuf->count)
+		goto done_with_rbuf;
+
+	/* More data to go, but can't copy any more? EOVERFLOW */
+	ret = -EOVERFLOW;
+	if (!nr)
+		goto done_with_rbuf;
+
+	/* Copy as much data as possible */
+	ret = rbuf->count - offset;
+	if (ret > nr)
+		ret = nr;
+	memcpy(kbuf, rbuf->buf+offset, ret);
+	offset += ret;
+
+	/* If we still have data left, we leave the rbuf in the cookie */
+	if (offset < rbuf->count)
+		return ret;
+
+done_with_rbuf:
+	*cookie = NULL;
+
+	if (n_hdlc->rx_free_buf_list.count > DEFAULT_RX_BUF_COUNT)
+		kfree(rbuf);
+	else
+		n_hdlc_buf_put(&n_hdlc->rx_free_buf_list, rbuf);
+
 	return ret;
 
 }	/* end of n_hdlc_tty_read() */
diff --git a/drivers/tty/n_null.c b/drivers/tty/n_null.c
index 96feabae4740..ce03ae78f5c6 100644
--- a/drivers/tty/n_null.c
+++ b/drivers/tty/n_null.c
@@ -20,7 +20,8 @@ static void n_null_close(struct tty_struct *tty)
 }
 
 static ssize_t n_null_read(struct tty_struct *tty, struct file *file,
-			   unsigned char __user * buf, size_t nr)
+			   unsigned char *buf, size_t nr,
+			   void **cookie, unsigned long offset)
 {
 	return -EOPNOTSUPP;
 }
diff --git a/drivers/tty/n_r3964.c b/drivers/tty/n_r3964.c
index 934dd2fb2ec8..3161f0a535e3 100644
--- a/drivers/tty/n_r3964.c
+++ b/drivers/tty/n_r3964.c
@@ -129,7 +129,7 @@ static void remove_client_block(struct r3964_info *pInfo,
 static int r3964_open(struct tty_struct *tty);
 static void r3964_close(struct tty_struct *tty);
 static ssize_t r3964_read(struct tty_struct *tty, struct file *file,
-		unsigned char __user * buf, size_t nr);
+		void *cookie, unsigned char *buf, size_t nr);
 static ssize_t r3964_write(struct tty_struct *tty, struct file *file,
 		const unsigned char *buf, size_t nr);
 static int r3964_ioctl(struct tty_struct *tty, struct file *file,
@@ -1058,7 +1058,8 @@ static void r3964_close(struct tty_struct *tty)
 }
 
 static ssize_t r3964_read(struct tty_struct *tty, struct file *file,
-			  unsigned char __user * buf, size_t nr)
+			  unsigned char *kbuf, size_t nr,
+			  void **cookie, unsigned long offset)
 {
 	struct r3964_info *pInfo = tty->disc_data;
 	struct r3964_client_info *pClient;
@@ -1109,10 +1110,7 @@ static ssize_t r3964_read(struct tty_struct *tty, struct file *file,
 		kfree(pMsg);
 		TRACE_M("r3964_read - msg kfree %p", pMsg);
 
-		if (copy_to_user(buf, &theMsg, ret)) {
-			ret = -EFAULT;
-			goto unlock;
-		}
+		memcpy(kbuf, &theMsg, ret);
 
 		TRACE_PS("read - return %d", ret);
 		goto unlock;
diff --git a/drivers/tty/n_tracerouter.c b/drivers/tty/n_tracerouter.c
index 4479af4d2fa5..3490ed51b1a3 100644
--- a/drivers/tty/n_tracerouter.c
+++ b/drivers/tty/n_tracerouter.c
@@ -118,7 +118,9 @@ static void n_tracerouter_close(struct tty_struct *tty)
  *	 -EINVAL
  */
 static ssize_t n_tracerouter_read(struct tty_struct *tty, struct file *file,
-				  unsigned char __user *buf, size_t nr) {
+				  unsigned char *buf, size_t nr,
+				  void **cookie, unsigned long offset)
+{
 	return -EINVAL;
 }
 
diff --git a/drivers/tty/n_tracesink.c b/drivers/tty/n_tracesink.c
index d96ba82cc356..1d9931041fd8 100644
--- a/drivers/tty/n_tracesink.c
+++ b/drivers/tty/n_tracesink.c
@@ -115,7 +115,9 @@ static void n_tracesink_close(struct tty_struct *tty)
  *	 -EINVAL
  */
 static ssize_t n_tracesink_read(struct tty_struct *tty, struct file *file,
-				unsigned char __user *buf, size_t nr) {
+				unsigned char *buf, size_t nr,
+				void **cookie, unsigned long offset)
+{
 	return -EINVAL;
 }
 
diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index 219e85756171..87ec15dbe10d 100644
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -164,29 +164,24 @@ static void zero_buffer(struct tty_struct *tty, u8 *buffer, int size)
 		memset(buffer, 0x00, size);
 }
 
-static int tty_copy_to_user(struct tty_struct *tty, void __user *to,
-			    size_t tail, size_t n)
+static void tty_copy(struct tty_struct *tty, void *to, size_t tail, size_t n)
 {
 	struct n_tty_data *ldata = tty->disc_data;
 	size_t size = N_TTY_BUF_SIZE - tail;
 	void *from = read_buf_addr(ldata, tail);
-	int uncopied;
 
 	if (n > size) {
 		tty_audit_add_data(tty, from, size);
-		uncopied = copy_to_user(to, from, size);
-		zero_buffer(tty, from, size - uncopied);
-		if (uncopied)
-			return uncopied;
+		memcpy(to, from, size);
+		zero_buffer(tty, from, size);
 		to += size;
 		n -= size;
 		from = ldata->read_buf;
 	}
 
 	tty_audit_add_data(tty, from, n);
-	uncopied = copy_to_user(to, from, n);
-	zero_buffer(tty, from, n - uncopied);
-	return uncopied;
+	memcpy(to, from, n);
+	zero_buffer(tty, from, n);
 }
 
 /**
@@ -1894,8 +1889,10 @@ static void n_tty_close(struct tty_struct *tty)
 	if (tty->link)
 		n_tty_packet_mode_flush(tty);
 
+	down_write(&tty->termios_rwsem);
 	vfree(ldata);
 	tty->disc_data = NULL;
+	up_write(&tty->termios_rwsem);
 }
 
 /**
@@ -1944,42 +1941,38 @@ static inline int input_available_p(struct tty_struct *tty, int poll)
 /**
  *	copy_from_read_buf	-	copy read data directly
  *	@tty: terminal device
- *	@b: user data
+ *	@kbp: data
  *	@nr: size of data
  *
  *	Helper function to speed up n_tty_read.  It is only called when
- *	ICANON is off; it copies characters straight from the tty queue to
- *	user space directly.  It can be profitably called twice; once to
- *	drain the space from the tail pointer to the (physical) end of the
- *	buffer, and once to drain the space from the (physical) beginning of
- *	the buffer to head pointer.
+ *	ICANON is off; it copies characters straight from the tty queue.
  *
  *	Called under the ldata->atomic_read_lock sem
  *
+ *	Returns true if it successfully copied data, but there is still
+ *	more data to be had.
+ *
  *	n_tty_read()/consumer path:
  *		caller holds non-exclusive termios_rwsem
  *		read_tail published
  */
 
-static int copy_from_read_buf(struct tty_struct *tty,
-				      unsigned char __user **b,
+static bool copy_from_read_buf(struct tty_struct *tty,
+				      unsigned char **kbp,
 				      size_t *nr)
 
 {
 	struct n_tty_data *ldata = tty->disc_data;
-	int retval;
 	size_t n;
 	bool is_eof;
 	size_t head = smp_load_acquire(&ldata->commit_head);
 	size_t tail = ldata->read_tail & (N_TTY_BUF_SIZE - 1);
 
-	retval = 0;
 	n = min(head - ldata->read_tail, N_TTY_BUF_SIZE - tail);
 	n = min(*nr, n);
 	if (n) {
 		unsigned char *from = read_buf_addr(ldata, tail);
-		retval = copy_to_user(*b, from, n);
-		n -= retval;
+		memcpy(*kbp, from, n);
 		is_eof = n == 1 && *from == EOF_CHAR(tty);
 		tty_audit_add_data(tty, from, n);
 		zero_buffer(tty, from, n);
@@ -1987,22 +1980,25 @@ static int copy_from_read_buf(struct tty_struct *tty,
 		/* Turn single EOF into zero-length read */
 		if (L_EXTPROC(tty) && ldata->icanon && is_eof &&
 		    (head == ldata->read_tail))
-			n = 0;
-		*b += n;
+			return false;
+		*kbp += n;
 		*nr -= n;
+
+		/* If we have more to copy, let the caller know */
+		return head != ldata->read_tail;
 	}
-	return retval;
+	return false;
 }
 
 /**
  *	canon_copy_from_read_buf	-	copy read data in canonical mode
  *	@tty: terminal device
- *	@b: user data
+ *	@kbp: data
  *	@nr: size of data
  *
  *	Helper function for n_tty_read.  It is only called when ICANON is on;
  *	it copies one line of input up to and including the line-delimiting
- *	character into the user-space buffer.
+ *	character into the result buffer.
  *
  *	NB: When termios is changed from non-canonical to canonical mode and
  *	the read buffer contains data, n_tty_set_termios() simulates an EOF
@@ -2017,21 +2013,22 @@ static int copy_from_read_buf(struct tty_struct *tty,
  *		read_tail published
  */
 
-static int canon_copy_from_read_buf(struct tty_struct *tty,
-				    unsigned char __user **b,
-				    size_t *nr)
+static bool canon_copy_from_read_buf(struct tty_struct *tty,
+				     unsigned char **kbp,
+				     size_t *nr)
 {
 	struct n_tty_data *ldata = tty->disc_data;
 	size_t n, size, more, c;
 	size_t eol;
-	size_t tail;
-	int ret, found = 0;
+	size_t tail, canon_head;
+	int found = 0;
 
 	/* N.B. avoid overrun if nr == 0 */
 	if (!*nr)
-		return 0;
+		return false;
 
-	n = min(*nr + 1, smp_load_acquire(&ldata->canon_head) - ldata->read_tail);
+	canon_head = smp_load_acquire(&ldata->canon_head);
+	n = min(*nr + 1, canon_head - ldata->read_tail);
 
 	tail = ldata->read_tail & (N_TTY_BUF_SIZE - 1);
 	size = min_t(size_t, tail + n, N_TTY_BUF_SIZE);
@@ -2061,10 +2058,8 @@ static int canon_copy_from_read_buf(struct tty_struct *tty,
 	n_tty_trace("%s: eol:%zu found:%d n:%zu c:%zu tail:%zu more:%zu\n",
 		    __func__, eol, found, n, c, tail, more);
 
-	ret = tty_copy_to_user(tty, *b, tail, n);
-	if (ret)
-		return -EFAULT;
-	*b += n;
+	tty_copy(tty, *kbp, tail, n);
+	*kbp += n;
 	*nr -= n;
 
 	if (found)
@@ -2077,8 +2072,11 @@ static int canon_copy_from_read_buf(struct tty_struct *tty,
 		else
 			ldata->push = 0;
 		tty_audit_push();
+		return false;
 	}
-	return 0;
+
+	/* No EOL found - do a continuation retry if there is more data */
+	return ldata->read_tail != canon_head;
 }
 
 /**
@@ -2129,10 +2127,11 @@ static int job_control(struct tty_struct *tty, struct file *file)
  */
 
 static ssize_t n_tty_read(struct tty_struct *tty, struct file *file,
-			 unsigned char __user *buf, size_t nr)
+			  unsigned char *kbuf, size_t nr,
+			  void **cookie, unsigned long offset)
 {
 	struct n_tty_data *ldata = tty->disc_data;
-	unsigned char __user *b = buf;
+	unsigned char *kb = kbuf;
 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
 	int c;
 	int minimum, time;
@@ -2141,6 +2140,30 @@ static ssize_t n_tty_read(struct tty_struct *tty, struct file *file,
 	int packet;
 	size_t tail;
 
+	/*
+	 * Is this a continuation of a read started earler?
+	 *
+	 * If so, we still hold the atomic_read_lock and the
+	 * termios_rwsem, and can just continue to copy data.
+	 */
+	if (*cookie) {
+		if (ldata->icanon && !L_EXTPROC(tty)) {
+			if (canon_copy_from_read_buf(tty, &kb, &nr))
+				return kb - kbuf;
+		} else {
+			if (copy_from_read_buf(tty, &kb, &nr))
+				return kb - kbuf;
+		}
+
+		/* No more data - release locks and stop retries */
+		n_tty_kick_worker(tty);
+		n_tty_check_unthrottle(tty);
+		up_read(&tty->termios_rwsem);
+		mutex_unlock(&ldata->atomic_read_lock);
+		*cookie = NULL;
+		return kb - kbuf;
+	}
+
 	c = job_control(tty, file);
 	if (c < 0)
 		return c;
@@ -2178,17 +2201,13 @@ static ssize_t n_tty_read(struct tty_struct *tty, struct file *file,
 		/* First test for status change. */
 		if (packet && tty->link->ctrl_status) {
 			unsigned char cs;
-			if (b != buf)
+			if (kb != kbuf)
 				break;
 			spin_lock_irq(&tty->link->ctrl_lock);
 			cs = tty->link->ctrl_status;
 			tty->link->ctrl_status = 0;
 			spin_unlock_irq(&tty->link->ctrl_lock);
-			if (put_user(cs, b)) {
-				retval = -EFAULT;
-				break;
-			}
-			b++;
+			*kb++ = cs;
 			nr--;
 			break;
 		}
@@ -2231,33 +2250,35 @@ static ssize_t n_tty_read(struct tty_struct *tty, struct file *file,
 		}
 
 		if (ldata->icanon && !L_EXTPROC(tty)) {
-			retval = canon_copy_from_read_buf(tty, &b, &nr);
-			if (retval)
-				break;
+			if (canon_copy_from_read_buf(tty, &kb, &nr))
+				goto more_to_be_read;
 		} else {
-			int uncopied;
-
 			/* Deal with packet mode. */
-			if (packet && b == buf) {
-				if (put_user(TIOCPKT_DATA, b)) {
-					retval = -EFAULT;
-					break;
-				}
-				b++;
+			if (packet && kb == kbuf) {
+				*kb++ = TIOCPKT_DATA;
 				nr--;
 			}
 
-			uncopied = copy_from_read_buf(tty, &b, &nr);
-			uncopied += copy_from_read_buf(tty, &b, &nr);
-			if (uncopied) {
-				retval = -EFAULT;
-				break;
+			/*
+			 * Copy data, and if there is more to be had
+			 * and we have nothing more to wait for, then
+			 * let's mark us for retries.
+			 *
+			 * NOTE! We return here with both the termios_sem
+			 * and atomic_read_lock still held, the retries
+			 * will release them when done.
+			 */
+			if (copy_from_read_buf(tty, &kb, &nr) && kb - kbuf >= minimum) {
+more_to_be_read:
+				remove_wait_queue(&tty->read_wait, &wait);
+				*cookie = cookie;
+				return kb - kbuf;
 			}
 		}
 
 		n_tty_check_unthrottle(tty);
 
-		if (b - buf >= minimum)
+		if (kb - kbuf >= minimum)
 			break;
 		if (time)
 			timeout = time;
@@ -2269,8 +2290,8 @@ static ssize_t n_tty_read(struct tty_struct *tty, struct file *file,
 	remove_wait_queue(&tty->read_wait, &wait);
 	mutex_unlock(&ldata->atomic_read_lock);
 
-	if (b - buf)
-		retval = b - buf;
+	if (kb - kbuf)
+		retval = kb - kbuf;
 
 	return retval;
 }
diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c
index a59f1e062bc6..8b2797b6ee44 100644
--- a/drivers/tty/pty.c
+++ b/drivers/tty/pty.c
@@ -45,7 +45,6 @@ static DEFINE_MUTEX(devpts_mutex);
 
 static void pty_close(struct tty_struct *tty, struct file *filp)
 {
-	BUG_ON(!tty);
 	if (tty->driver->subtype == PTY_TYPE_MASTER)
 		WARN_ON(tty->count > 1);
 	else {
@@ -67,7 +66,8 @@ static void pty_close(struct tty_struct *tty, struct file *filp)
 	wake_up_interruptible(&tty->link->read_wait);
 	wake_up_interruptible(&tty->link->write_wait);
 	if (tty->driver->subtype == PTY_TYPE_MASTER) {
-		set_bit(TTY_OTHER_CLOSED, &tty->flags);
+		struct file *f;
+
 #ifdef CONFIG_UNIX98_PTYS
 		if (tty->driver == ptm_driver) {
 			mutex_lock(&devpts_mutex);
@@ -76,7 +76,17 @@ static void pty_close(struct tty_struct *tty, struct file *filp)
 			mutex_unlock(&devpts_mutex);
 		}
 #endif
-		tty_vhangup(tty->link);
+
+		/*
+		 * This hack is required because a program can open a
+		 * pty and redirect a console to it, but if the pty is
+		 * closed and the console is not released, then the
+		 * slave side will never close.  So release the
+		 * redirect when the master closes.
+		 */
+		f = tty_release_redirect(tty->link);
+		if (f)
+			fput(f);
 	}
 }
 
diff --git a/drivers/tty/serial/8250/8250_tegra.c b/drivers/tty/serial/8250/8250_tegra.c
index c0ffad1572c6..e13ae18b0713 100644
--- a/drivers/tty/serial/8250/8250_tegra.c
+++ b/drivers/tty/serial/8250/8250_tegra.c
@@ -26,16 +26,17 @@ static void tegra_uart_handle_break(struct uart_port *p)
 {
 	unsigned int status, tmout = 10000;
 
-	do {
+	while (1) {
 		status = p->serial_in(p, UART_LSR);
-		if (status & (UART_LSR_FIFOE | UART_LSR_BRK_ERROR_BITS))
-			status = p->serial_in(p, UART_RX);
-		else
+		if (!(status & (UART_LSR_FIFOE | UART_LSR_BRK_ERROR_BITS)))
 			break;
+
+		p->serial_in(p, UART_RX);
+
 		if (--tmout == 0)
 			break;
 		udelay(1);
-	} while (1);
+	}
 }
 
 static int tegra_uart_probe(struct platform_device *pdev)
diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 34a2899e69c0..0c4cd4a348f4 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -276,28 +276,6 @@ config SERIAL_SAMSUNG_CONSOLE
 	  your boot loader about how to pass options to the kernel at
 	  boot time.)
 
-config SERIAL_SIRFSOC
-	tristate "SiRF SoC Platform Serial port support"
-	depends on ARCH_SIRF
-	select SERIAL_CORE
-	help
-	  Support for the on-chip UART on the CSR SiRFprimaII series,
-	  providing /dev/ttySiRF0, 1 and 2 (note, some machines may not
-	  provide all of these ports, depending on how the serial port
-	  pins are configured).
-
-config SERIAL_SIRFSOC_CONSOLE
-	bool "Support for console on SiRF SoC serial port"
-	depends on SERIAL_SIRFSOC=y
-	select SERIAL_CORE_CONSOLE
-	help
-	  Even if you say Y here, the currently visible virtual console
-	  (/dev/tty0) will still be used as the system console by default, but
-	  you can alter that using a kernel command line option such as
-	  "console=ttySiRFx". (Try "man bootparam" or see the documentation of
-	  your boot loader about how to pass options to the kernel at
-	  boot time.)
-
 config SERIAL_TEGRA
 	tristate "NVIDIA Tegra20/30 SoC serial controller"
 	depends on ARCH_TEGRA && TEGRA20_APB_DMA
@@ -1204,13 +1182,6 @@ config SERIAL_ALTERA_UART_CONSOLE
 	help
 	  Enable a Altera UART port to be the system console.
 
-config SERIAL_IFX6X60
-	tristate "SPI protocol driver for Infineon 6x60 modem (EXPERIMENTAL)"
-	depends on GPIOLIB || COMPILE_TEST
-	depends on SPI && HAS_DMA
-	help
-	  Support for the IFX6x60 modem devices on Intel MID platforms.
-
 config SERIAL_PCH_UART
 	tristate "Intel EG20T PCH/LAPIS Semicon IOH(ML7213/ML7223/ML7831) UART"
 	depends on PCI && (X86_32 || MIPS ||  COMPILE_TEST)
@@ -1295,14 +1266,6 @@ config SERIAL_AR933X_NR_UARTS
 	  Set this to the number of serial ports you want the driver
 	  to support.
 
-config SERIAL_EFM32_UART
-	tristate "EFM32 UART/USART port"
-	depends on ARM && (ARCH_EFM32 || COMPILE_TEST)
-	select SERIAL_CORE
-	help
-	  This driver support the USART and UART ports on
-	  Energy Micro's efm32 SoCs.
-
 config SERIAL_MPS2_UART_CONSOLE
 	bool "MPS2 UART console support"
 	depends on SERIAL_MPS2_UART
@@ -1316,11 +1279,6 @@ config SERIAL_MPS2_UART
 	help
 	  This driver support the UART ports on ARM MPS2.
 
-config SERIAL_EFM32_UART_CONSOLE
-	bool "EFM32 UART/USART console support"
-	depends on SERIAL_EFM32_UART=y
-	select SERIAL_CORE_CONSOLE
-
 config SERIAL_ARC
 	tristate "ARC UART driver support"
 	select