Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6

* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: (49 commits)
  serial8250: ratelimit "too much work" error
  serial: bfin_sport_uart: speed up sport RX sample rate to be 3% faster
  serial: abstraction for 8250 legacy ports
  serial/imx: check that the buffer is non-empty before sending it out
  serial: mfd: add more baud rates support
  jsm: Remove the uart port on errors
  Alchemy: Add UART PM methods.
  8250: allow platforms to override PM hook.
  altera_uart: Don't use plain integer as NULL pointer
  altera_uart: Fix missing prototype for registering an early console
  altera_uart: Fixup type usage of port flags
  altera_uart: Make it possible to use Altera UART and 8250 ports together
  altera_uart: Add support for different address strides
  altera_uart: Add support for getting mapbase and IRQ from resources
  altera_uart: Add support for polling mode (IRQ-less)
  serial: Factor out uart_poll_timeout() from 8250 driver
  serial: mark the 8250 driver as maintained
  serial: 8250: Don't delay after transmitter is ready.
  tty: MAINTAINERS: add drivers/serial/jsm/ as maintained driver
  vcs: invoke the vt update callback when /dev/vcs* is written to
  ...

16 files changed, 748 insertions, 286 deletions

diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
index 3d44ec724c1..43d3395325c 100644
--- a/drivers/char/Kconfig
+++ b/drivers/char/Kconfig
@@ -493,6 +493,21 @@ config LEGACY_PTY_COUNT
 	  When not in use, each legacy PTY occupies 12 bytes on 32-bit
 	  architectures and 24 bytes on 64-bit architectures.
 
+config TTY_PRINTK
+	bool "TTY driver to output user messages via printk"
+	depends on EMBEDDED
+	default n
+	---help---
+	  If you say Y here, the support for writing user messages (i.e.
+	  console messages) via printk is available.
+
+	  The feature is useful to inline user messages with kernel
+	  messages.
+	  In order to use this feature, you should output user messages
+	  to /dev/ttyprintk or redirect console to this TTY.
+
+	  If unsure, say N.
+
 config BRIQ_PANEL
 	tristate 'Total Impact briQ front panel driver'
 	depends on PPC_CHRP
diff --git a/drivers/char/Makefile b/drivers/char/Makefile
index dc964166060..3a9c0141683 100644
--- a/drivers/char/Makefile
+++ b/drivers/char/Makefile
@@ -12,6 +12,7 @@ obj-y	 += mem.o random.o tty_io.o n_tty.o tty_ioctl.o tty_ldisc.o tty_buffer.o t
 obj-y				+= tty_mutex.o
 obj-$(CONFIG_LEGACY_PTYS)	+= pty.o
 obj-$(CONFIG_UNIX98_PTYS)	+= pty.o
+obj-$(CONFIG_TTY_PRINTK)	+= ttyprintk.o
 obj-y				+= misc.o
 obj-$(CONFIG_VT)		+= vt_ioctl.o vc_screen.o selection.o keyboard.o
 obj-$(CONFIG_BFIN_JTAG_COMM)	+= bfin_jtag_comm.o
diff --git a/drivers/char/amiserial.c b/drivers/char/amiserial.c
index a11c8c9ca3d..b0a70461a12 100644
--- a/drivers/char/amiserial.c
+++ b/drivers/char/amiserial.c
@@ -1263,6 +1263,36 @@ static int rs_break(struct tty_struct *tty, int break_state)
 	return 0;
 }
 
+/*
+ * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
+ * Return: write counters to the user passed counter struct
+ * NB: both 1->0 and 0->1 transitions are counted except for
+ *     RI where only 0->1 is counted.
+ */
+static int rs_get_icount(struct tty_struct *tty,
+				struct serial_icounter_struct *icount)
+{
+	struct async_struct *info = tty->driver_data;
+	struct async_icount cnow;
+	unsigned long flags;
+
+	local_irq_save(flags);
+	cnow = info->state->icount;
+	local_irq_restore(flags);
+	icount->cts = cnow.cts;
+	icount->dsr = cnow.dsr;
+	icount->rng = cnow.rng;
+	icount->dcd = cnow.dcd;
+	icount->rx = cnow.rx;
+	icount->tx = cnow.tx;
+	icount->frame = cnow.frame;
+	icount->overrun = cnow.overrun;
+	icount->parity = cnow.parity;
+	icount->brk = cnow.brk;
+	icount->buf_overrun = cnow.buf_overrun;
+
+	return 0;
+}
 
 static int rs_ioctl(struct tty_struct *tty, struct file * file,
 		    unsigned int cmd, unsigned long arg)
@@ -1332,31 +1362,6 @@ static int rs_ioctl(struct tty_struct *tty, struct file * file,
 			}
 			/* NOTREACHED */
 
-		/* 
-		 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
-		 * Return: write counters to the user passed counter struct
-		 * NB: both 1->0 and 0->1 transitions are counted except for
-		 *     RI where only 0->1 is counted.
-		 */
-		case TIOCGICOUNT:
-			local_irq_save(flags);
-			cnow = info->state->icount;
-			local_irq_restore(flags);
-			icount.cts = cnow.cts;
-			icount.dsr = cnow.dsr;
-			icount.rng = cnow.rng;
-			icount.dcd = cnow.dcd;
-			icount.rx = cnow.rx;
-			icount.tx = cnow.tx;
-			icount.frame = cnow.frame;
-			icount.overrun = cnow.overrun;
-			icount.parity = cnow.parity;
-			icount.brk = cnow.brk;
-			icount.buf_overrun = cnow.buf_overrun;
-
-			if (copy_to_user(argp, &icount, sizeof(icount)))
-				return -EFAULT;
-			return 0;
 		case TIOCSERGWILD:
 		case TIOCSERSWILD:
 			/* "setserial -W" is called in Debian boot */
@@ -1958,6 +1963,7 @@ static const struct tty_operations serial_ops = {
 	.wait_until_sent = rs_wait_until_sent,
 	.tiocmget = rs_tiocmget,
 	.tiocmset = rs_tiocmset,
+	.get_icount = rs_get_icount,
 	.proc_fops = &rs_proc_fops,
 };
 
diff --git a/drivers/char/cyclades.c b/drivers/char/cyclades.c
index 27aad942233..4f152c28f40 100644
--- a/drivers/char/cyclades.c
+++ b/drivers/char/cyclades.c
@@ -2790,29 +2790,6 @@ cy_ioctl(struct tty_struct *tty, struct file *file,
 		 * NB: both 1->0 and 0->1 transitions are counted except for
 		 *     RI where only 0->1 is counted.
 		 */
-	case TIOCGICOUNT: {
-		struct serial_icounter_struct sic = { };
-
-		spin_lock_irqsave(&info->card->card_lock, flags);
-		cnow = info->icount;
-		spin_unlock_irqrestore(&info->card->card_lock, flags);
-
-		sic.cts = cnow.cts;
-		sic.dsr = cnow.dsr;
-		sic.rng = cnow.rng;
-		sic.dcd = cnow.dcd;
-		sic.rx = cnow.rx;
-		sic.tx = cnow.tx;
-		sic.frame = cnow.frame;
-		sic.overrun = cnow.overrun;
-		sic.parity = cnow.parity;
-		sic.brk = cnow.brk;
-		sic.buf_overrun = cnow.buf_overrun;
-
-		if (copy_to_user(argp, &sic, sizeof(sic)))
-			ret_val = -EFAULT;
-		break;
-	}
 	default:
 		ret_val = -ENOIOCTLCMD;
 	}
@@ -2823,6 +2800,31 @@ cy_ioctl(struct tty_struct *tty, struct file *file,
 	return ret_val;
 }				/* cy_ioctl */
 
+static int cy_get_icount(struct tty_struct *tty,
+				struct serial_icounter_struct *sic)
+{
+	struct cyclades_port *info = tty->driver_data;
+	struct cyclades_icount cnow;	/* Used to snapshot */
+	unsigned long flags;
+
+	spin_lock_irqsave(&info->card->card_lock, flags);
+	cnow = info->icount;
+	spin_unlock_irqrestore(&info->card->card_lock, flags);
+
+	sic->cts = cnow.cts;
+	sic->dsr = cnow.dsr;
+	sic->rng = cnow.rng;
+	sic->dcd = cnow.dcd;
+	sic->rx = cnow.rx;
+	sic->tx = cnow.tx;
+	sic->frame = cnow.frame;
+	sic->overrun = cnow.overrun;
+	sic->parity = cnow.parity;
+	sic->brk = cnow.brk;
+	sic->buf_overrun = cnow.buf_overrun;
+	return 0;
+}
+
 /*
  * This routine allows the tty driver to be notified when
  * device's termios settings have changed.  Note that a
@@ -4084,6 +4086,7 @@ static const struct tty_operations cy_ops = {
 	.wait_until_sent = cy_wait_until_sent,
 	.tiocmget = cy_tiocmget,
 	.tiocmset = cy_tiocmset,
+	.get_icount = cy_get_icount,
 	.proc_fops = &cyclades_proc_fops,
 };
 
diff --git a/drivers/char/ip2/ip2main.c b/drivers/char/ip2/ip2main.c
index 64a439ce2f8..fcd02baa7d6 100644
--- a/drivers/char/ip2/ip2main.c
+++ b/drivers/char/ip2/ip2main.c
@@ -184,6 +184,8 @@ static void ip2_hangup(PTTY);
 static int  ip2_tiocmget(struct tty_struct *tty, struct file *file);
 static int  ip2_tiocmset(struct tty_struct *tty, struct file *file,
 			 unsigned int set, unsigned int clear);
+static int ip2_get_icount(struct tty_struct *tty,
+		struct serial_icounter_struct *icount);
 
 static void set_irq(int, int);
 static void ip2_interrupt_bh(struct work_struct *work);
@@ -456,6 +458,7 @@ static const struct tty_operations ip2_ops = {
 	.hangup          = ip2_hangup,
 	.tiocmget	 = ip2_tiocmget,
 	.tiocmset	 = ip2_tiocmset,
+	.get_icount	 = ip2_get_icount,
 	.proc_fops	 = &ip2_proc_fops,
 };
 
@@ -2130,7 +2133,6 @@ ip2_ioctl ( PTTY tty, struct file *pFile, UINT cmd, ULONG arg )
 	i2ChanStrPtr pCh = DevTable[tty->index];
 	i2eBordStrPtr pB;
 	struct async_icount cprev, cnow;	/* kernel counter temps */
-	struct serial_icounter_struct __user *p_cuser;
 	int rc = 0;
 	unsigned long flags;
 	void __user *argp = (void __user *)arg;
@@ -2299,34 +2301,6 @@ ip2_ioctl ( PTTY tty, struct file *pFile, UINT cmd, ULONG arg )
 		break;
 
 	/*
-	 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
-	 * Return: write counters to the user passed counter struct
-	 * NB: both 1->0 and 0->1 transitions are counted except for RI where
-	 * only 0->1 is counted. The controller is quite capable of counting
-	 * both, but this done to preserve compatibility with the standard
-	 * serial driver.
-	 */
-	case TIOCGICOUNT:
-		ip2trace (CHANN, ITRC_IOCTL, 11, 1, rc );
-
-		write_lock_irqsave(&pB->read_fifo_spinlock, flags);
-		cnow = pCh->icount;
-		write_unlock_irqrestore(&pB->read_fifo_spinlock, flags);
-		p_cuser = argp;
-		rc = put_user(cnow.cts, &p_cuser->cts);
-		rc = put_user(cnow.dsr, &p_cuser->dsr);
-		rc = put_user(cnow.rng, &p_cuser->rng);
-		rc = put_user(cnow.dcd, &p_cuser->dcd);
-		rc = put_user(cnow.rx, &p_cuser->rx);
-		rc = put_user(cnow.tx, &p_cuser->tx);
-		rc = put_user(cnow.frame, &p_cuser->frame);
-		rc = put_user(cnow.overrun, &p_cuser->overrun);
-		rc = put_user(cnow.parity, &p_cuser->parity);
-		rc = put_user(cnow.brk, &p_cuser->brk);
-		rc = put_user(cnow.buf_overrun, &p_cuser->buf_overrun);
-		break;
-
-	/*
 	 * The rest are not supported by this driver. By returning -ENOIOCTLCMD they
 	 * will be passed to the line discipline for it to handle.
 	 */
@@ -2350,6 +2324,46 @@ ip2_ioctl ( PTTY tty, struct file *pFile, UINT cmd, ULONG arg )
 	return rc;
 }
 
+static int ip2_get_icount(struct tty_struct *tty,
+		struct serial_icounter_struct *icount)
+{
+	i2ChanStrPtr pCh = DevTable[tty->index];
+	i2eBordStrPtr pB;
+	struct async_icount cnow;	/* kernel counter temp */
+	unsigned long flags;
+
+	if ( pCh == NULL )
+		return -ENODEV;
+
+	pB = pCh->pMyBord;
+
+	/*
+	 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
+	 * Return: write counters to the user passed counter struct
+	 * NB: both 1->0 and 0->1 transitions are counted except for RI where
+	 * only 0->1 is counted. The controller is quite capable of counting
+	 * both, but this done to preserve compatibility with the standard
+	 * serial driver.
+	 */
+
+	write_lock_irqsave(&pB->read_fifo_spinlock, flags);
+	cnow = pCh->icount;
+	write_unlock_irqrestore(&pB->read_fifo_spinlock, flags);
+
+	icount->cts = cnow.cts;
+	icount->dsr = cnow.dsr;
+	icount->rng = cnow.rng;
+	icount->dcd = cnow.dcd;
+	icount->rx = cnow.rx;
+	icount->tx = cnow.tx;
+	icount->frame = cnow.frame;
+	icount->overrun = cnow.overrun;
+	icount->parity = cnow.parity;
+	icount->brk = cnow.brk;
+	icount->buf_overrun = cnow.buf_overrun;
+	return 0;
+}
+
 /******************************************************************************/
 /* Function:   GetSerialInfo()                                                */
 /* Parameters: Pointer to channel structure                                   */
diff --git a/drivers/char/mxser.c b/drivers/char/mxser.c
index 3fc89da856a..463df27494b 100644
--- a/drivers/char/mxser.c
+++ b/drivers/char/mxser.c
@@ -1700,7 +1700,7 @@ static int mxser_ioctl(struct tty_struct *tty, struct file *file,
 		return 0;
 	}
 
-	if (cmd != TIOCGSERIAL && cmd != TIOCMIWAIT && cmd != TIOCGICOUNT &&
+	if (cmd != TIOCGSERIAL && cmd != TIOCMIWAIT &&
 			test_bit(TTY_IO_ERROR, &tty->flags))
 		return -EIO;
 
@@ -1730,32 +1730,6 @@ static int mxser_ioctl(struct tty_struct *tty, struct file *file,
 
 		return wait_event_interruptible(info->port.delta_msr_wait,
 				mxser_cflags_changed(info, arg, &cnow));
-	/*
-	 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
-	 * Return: write counters to the user passed counter struct
-	 * NB: both 1->0 and 0->1 transitions are counted except for
-	 *     RI where only 0->1 is counted.
-	 */
-	case TIOCGICOUNT: {
-		struct serial_icounter_struct icnt = { 0 };
-		spin_lock_irqsave(&info->slock, flags);
-		cnow = info->icount;
-		spin_unlock_irqrestore(&info->slock, flags);
-
-		icnt.frame = cnow.frame;
-		icnt.brk = cnow.brk;
-		icnt.overrun = cnow.overrun;
-		icnt.buf_overrun = cnow.buf_overrun;
-		icnt.parity = cnow.parity;
-		icnt.rx = cnow.rx;
-		icnt.tx = cnow.tx;
-		icnt.cts = cnow.cts;
-		icnt.dsr = cnow.dsr;
-		icnt.rng = cnow.rng;
-		icnt.dcd = cnow.dcd;
-
-		return copy_to_user(argp, &icnt, sizeof(icnt)) ? -EFAULT : 0;
-	}
 	case MOXA_HighSpeedOn:
 		return put_user(info->baud_base != 115200 ? 1 : 0, (int __user *)argp);
 	case MOXA_SDS_RSTICOUNTER:
@@ -1828,6 +1802,39 @@ static int mxser_ioctl(struct tty_struct *tty, struct file *file,
 	return 0;
 }
 
+	/*
+	 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
+	 * Return: write counters to the user passed counter struct
+	 * NB: both 1->0 and 0->1 transitions are counted except for
+	 *     RI where only 0->1 is counted.
+	 */
+
+static int mxser_get_icount(struct tty_struct *tty,
+		struct serial_icounter_struct *icount)
+
+{
+	struct mxser_port *info = tty->driver_data;
+	struct async_icount cnow;
+	unsigned long flags;
+
+	spin_lock_irqsave(&info->slock, flags);
+	cnow = info->icount;
+	spin_unlock_irqrestore(&info->slock, flags);
+
+	icount->frame = cnow.frame;
+	icount->brk = cnow.brk;
+	icount->overrun = cnow.overrun;
+	icount->buf_overrun = cnow.buf_overrun;
+	icount->parity = cnow.parity;
+	icount->rx = cnow.rx;
+	icount->tx = cnow.tx;
+	icount->cts = cnow.cts;
+	icount->dsr = cnow.dsr;
+	icount->rng = cnow.rng;
+	icount->dcd = cnow.dcd;
+	return 0;
+}
+
 static void mxser_stoprx(struct tty_struct *tty)
 {
 	struct mxser_port *info = tty->driver_data;
@@ -2326,6 +2333,7 @@ static const struct tty_operations mxser_ops = {
 	.wait_until_sent = mxser_wait_until_sent,
 	.tiocmget = mxser_tiocmget,
 	.tiocmset = mxser_tiocmset,
+	.get_icount = mxser_get_icount,
 };
 
 struct tty_port_operations mxser_port_ops = {
@@ -2339,20 +2347,11 @@ struct tty_port_operations mxser_port_ops = {
  * The MOXA Smartio/Industio serial driver boot-time initialization code!
  */
 
-static void mxser_release_res(struct mxser_board *brd, struct pci_dev *pdev,
-		unsigned int irq)
+static void mxser_release_ISA_res(struct mxser_board *brd)
 {
-	if (irq)
-		free_irq(brd->irq, brd);
-	if (pdev != NULL) {	/* PCI */
-#ifdef CONFIG_PCI
-		pci_release_region(pdev, 2);
-		pci_release_region(pdev, 3);
-#endif
-	} else {
-		release_region(brd->ports[0].ioaddr, 8 * brd->info->nports);
-		release_region(brd->vector, 1);
-	}
+	free_irq(brd->irq, brd);
+	release_region(brd->ports[0].ioaddr, 8 * brd->info->nports);
+	release_region(brd->vector, 1);
 }
 
 static int __devinit mxser_initbrd(struct mxser_board *brd,
@@ -2397,13 +2396,11 @@ static int __devinit mxser_initbrd(struct mxser_board *brd,
 
 	retval = request_irq(brd->irq, mxser_interrupt, IRQF_SHARED, "mxser",
 			brd);
-	if (retval) {
+	if (retval)
 		printk(KERN_ERR "Board %s: Request irq failed, IRQ (%d) may "
 			"conflict with another device.\n",
 			brd->info->name, brd->irq);
-		/* We hold resources, we need to release them. */
-		mxser_release_res(brd, pdev, 0);
-	}
+
 	return retval;
 }
 
@@ -2555,7 +2552,7 @@ static int __devinit mxser_probe(struct pci_dev *pdev,
 	ioaddress = pci_resource_start(pdev, 2);
 	retval = pci_request_region(pdev, 2, "mxser(IO)");
 	if (retval)
-		goto err;
+		goto err_dis;
 
 	brd->info = &mxser_cards[ent->driver_data];
 	for (i = 0; i < brd->info->nports; i++)
@@ -2565,7 +2562,7 @@ static int __devinit mxser_probe(struct pci_dev *pdev,
 	ioaddress = pci_resource_start(pdev, 3);
 	retval = pci_request_region(pdev, 3, "mxser(vector)");
 	if (retval)
-		goto err_relio;
+		goto err_zero;
 	brd->vector = ioaddress;
 
 	/* irq */
@@ -2608,7 +2605,7 @@ static int __devinit mxser_probe(struct pci_dev *pdev,
 	/* mxser_initbrd will hook ISR. */
 	retval = mxser_initbrd(brd, pdev);
 	if (retval)
-		goto err_null;
+		goto err_rel3;
 
 	for (i = 0; i < brd->info->nports; i++)
 		tty_register_device(mxvar_sdriver, brd->idx + i, &pdev->dev);
@@ -2616,10 +2613,13 @@ static int __devinit mxser_probe(struct pci_dev *pdev,
 	pci_set_drvdata(pdev, brd);
 
 	return 0;
-err_relio:
-	pci_release_region(pdev, 2);
-err_null:
+err_rel3:
+	pci_release_region(pdev, 3);
+err_zero:
 	brd->info = NULL;
+	pci_release_region(pdev, 2);
+err_dis:
+	pci_disable_device(pdev);
 err:
 	return retval;
 #else
@@ -2629,14 +2629,19 @@ err:
 
 static void __devexit mxser_remove(struct pci_dev *pdev)
 {
+#ifdef CONFIG_PCI
 	struct mxser_board *brd = pci_get_drvdata(pdev);
 	unsigned int i;
 
 	for (i = 0; i < brd->info->nports; i++)
 		tty_unregister_device(mxvar_sdriver, brd->idx + i);
 
-	mxser_release_res(brd, pdev, 1);
+	free_irq(pdev->irq, brd);
+	pci_release_region(pdev, 2);
+	pci_release_region(pdev, 3);
+	pci_disable_device(pdev);
 	brd->info = NULL;
+#endif
 }
 
 static struct pci_driver mxser_driver = {
@@ -2741,7 +2746,7 @@ static void __exit mxser_module_exit(void)
 
 	for (i = 0; i < MXSER_BOARDS; i++)
 		if (mxser_boards[i].info != NULL)
-			mxser_release_res(&mxser_boards[i], NULL, 1);
+			mxser_release_ISA_res(&mxser_boards[i]);
 }
 
 module_init(mxser_module_init);
diff --git a/drivers/char/nozomi.c b/drivers/char/nozomi.c
index 817169cbb24..dd3f9b1f11b 100644
--- a/drivers/char/nozomi.c
+++ b/drivers/char/nozomi.c
@@ -1804,24 +1804,24 @@ static int ntty_cflags_changed(struct port *port, unsigned long flags,
 	return ret;
 }
 
-static int ntty_ioctl_tiocgicount(struct port *port, void __user *argp)
+static int ntty_tiocgicount(struct tty_struct *tty,
+				struct serial_icounter_struct *icount)
 {
+	struct port *port = tty->driver_data;
 	const struct async_icount cnow = port->tty_icount;
-	struct serial_icounter_struct icount;
-
-	icount.cts = cnow.cts;
-	icount.dsr = cnow.dsr;
-	icount.rng = cnow.rng;
-	icount.dcd = cnow.dcd;
-	icount.rx = cnow.rx;
-	icount.tx = cnow.tx;
-	icount.frame = cnow.frame;
-	icount.overrun = cnow.overrun;
-	icount.parity = cnow.parity;
-	icount.brk = cnow.brk;
-	icount.buf_overrun = cnow.buf_overrun;
-
-	return copy_to_user(argp, &icount, sizeof(icount)) ? -EFAULT : 0;
+
+	icount->cts = cnow.cts;
+	icount->dsr = cnow.dsr;
+	icount->rng = cnow.rng;
+	icount->dcd = cnow.dcd;
+	icount->rx = cnow.rx;
+	icount->tx = cnow.tx;
+	icount->frame = cnow.frame;
+	icount->overrun = cnow.overrun;
+	icount->parity = cnow.parity;
+	icount->brk = cnow.brk;
+	icount->buf_overrun = cnow.buf_overrun;
+	return 0;
 }
 
 static int ntty_ioctl(struct tty_struct *tty, struct file *file,
@@ -1840,9 +1840,7 @@ static int ntty_ioctl(struct tty_struct *tty, struct file *file,
 		rval = wait_event_interruptible(port->tty_wait,
 				ntty_cflags_changed(port, arg, &cprev));
 		break;
-	} case TIOCGICOUNT:
-		rval = ntty_ioctl_tiocgicount(port, argp);
-		break;
+	}
 	default:
 		DBG1("ERR: 0x%08X, %d", cmd, cmd);
 		break;
@@ -1922,6 +1920,7 @@ static const struct tty_operations tty_ops = {
 	.chars_in_buffer = ntty_chars_in_buffer,
 	.tiocmget = ntty_tiocmget,
 	.tiocmset = ntty_tiocmset,
+	.get_icount = ntty_tiocgicount,
 	.install = ntty_install,
 	.cleanup = ntty_cleanup,
 };
diff --git a/drivers/char/pcmcia/synclink_cs.c b/drivers/char/pcmcia/synclink_cs.c
index be181005760..bfc10f89d95 100644
--- a/drivers/char/pcmcia/synclink_cs.c
+++ b/drivers/char/pcmcia/synclink_cs.c
@@ -2191,6 +2191,32 @@ static int mgslpc_break(struct tty_struct *tty, int break_state)
 	return 0;
 }
 
+static int mgslpc_get_icount(struct tty_struct *tty,
+				struct serial_icounter_struct *icount)
+{
+	MGSLPC_INFO * info = (MGSLPC_INFO *)tty->driver_data;
+	struct mgsl_icount cnow;	/* kernel counter temps */
+	unsigned long flags;
+
+	spin_lock_irqsave(&info->lock,flags);
+	cnow = info->icount;
+	spin_unlock_irqrestore(&info->lock,flags);
+
+	icount->cts = cnow.cts;
+	icount->dsr = cnow.dsr;
+	icount->rng = cnow.rng;
+	icount->dcd = cnow.dcd;
+	icount->rx = cnow.rx;
+	icount->tx = cnow.tx;
+	icount->frame = cnow.frame;
+	icount->overrun = cnow.overrun;
+	icount->parity = cnow.parity;
+	icount->brk = cnow.brk;
+	icount->buf_overrun = cnow.buf_overrun;
+
+	return 0;
+}
+
 /* Service an IOCTL request
  *
  * Arguments:
@@ -2206,11 +2232,7 @@ static int mgslpc_ioctl(struct tty_struct *tty, struct file * file,
 			unsigned int cmd, unsigned long arg)
 {
 	MGSLPC_INFO * info = (MGSLPC_INFO *)tty->driver_data;
-	int error;
-	struct mgsl_icount cnow;	/* kernel counter temps */
-	struct serial_icounter_struct __user *p_cuser;	/* user space */
 	void __user *argp = (void __user *)arg;
-	unsigned long flags;
 
 	if (debug_level >= DEBUG_LEVEL_INFO)
 		printk("%s(%d):mgslpc_ioctl %s cmd=%08X\n", __FILE__,__LINE__,
@@ -2220,7 +2242,7 @@ static int mgslpc_ioctl(struct tty_struct *tty, struct file * file,
 		return -ENODEV;
 
 	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
-	    (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
+	    (cmd != TIOCMIWAIT)) {
 		if (tty->flags & (1 << TTY_IO_ERROR))
 		    return -EIO;
 	}
@@ -2250,34 +2272,6 @@ static int mgslpc_ioctl(struct tty_struct *tty, struct file * file,
 		return wait_events(info, argp);
 	case TIOCMIWAIT:
 		return modem_input_wait(info,(int)arg);
-	case TIOCGICOUNT:
-		spin_lock_irqsave(&info->lock,flags);
-		cnow = info->icount;
-		spin_unlock_irqrestore(&info->lock,flags);
-		p_cuser = argp;
-		PUT_USER(error,cnow.cts, &p_cuser->cts);
-		if (error) return error;
-		PUT_USER(error,cnow.dsr, &p_cuser->dsr);
-		if (error) return error;
-		PUT_USER(error,cnow.rng, &p_cuser->rng);
-		if (error) return error;
-		PUT_USER(error,cnow.dcd, &p_cuser->dcd);
-		if (error) return error;
-		PUT_USER(error,cnow.rx, &p_cuser->rx);
-		if (error) return error;
-		PUT_USER(error,cnow.tx, &p_cuser->tx);
-		if (error) return error;
-		PUT_USER(error,cnow.frame, &p_cuser->frame);
-		if (error) return error;
-		PUT_USER(error,cnow.overrun, &p_cuser->overrun);
-		if (error) return error;
-		PUT_USER(error,cnow.parity, &p_cuser->parity);
-		if (error) return error;
-		PUT_USER(error,cnow.brk, &p_cuser->brk);
-		if (error) return error;
-		PUT_USER(error,cnow.buf_overrun, &p_cuser->buf_overrun);
-		if (error) return error;
-		return 0;
 	default:
 		return -ENOIOCTLCMD;
 	}
diff --git a/drivers/char/pty.c b/drivers/char/pty.c
index c350d01716b..923a4858550 100644
--- a/drivers/char/pty.c
+++ b/drivers/char/pty.c
@@ -676,7 +676,9 @@ static int ptmx_open(struct inode *inode, struct file *filp)
 
 	set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */
 
-	tty_add_file(tty, filp);
+	retval = tty_add_file(tty, filp);
+	if (retval)
+		goto out;
 
 	retval = devpts_pty_new(inode, tty->link);
 	if (retval)
diff --git a/drivers/char/synclink.c b/drivers/char/synclink.c
index a2a58004e18..3a6824f12be 100644
--- a/drivers/char/synclink.c
+++ b/drivers/char/synclink.c
@@ -2925,6 +2925,38 @@ static int mgsl_break(struct tty_struct *tty, int break_state)
 	
 }	/* end of mgsl_break() */
 
+/*
+ * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
+ * Return: write counters to the user passed counter struct
+ * NB: both 1->0 and 0->1 transitions are counted except for
+ *     RI where only 0->1 is counted.
+ */
+static int msgl_get_icount(struct tty_struct *tty,
+				struct serial_icounter_struct *icount)
+
+{
+	struct mgsl_struct * info = tty->driver_data;
+	struct mgsl_icount cnow;	/* kernel counter temps */
+	unsigned long flags;
+
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	cnow = info->icount;
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+
+	icount->cts = cnow.cts;
+	icount->dsr = cnow.dsr;
+	icount->rng = cnow.rng;
+	icount->dcd = cnow.dcd;
+	icount->rx = cnow.rx;
+	icount->tx = cnow.tx;
+	icount->frame = cnow.frame;
+	icount->overrun = cnow.overrun;
+	icount->parity = cnow.parity;
+	icount->brk = cnow.brk;
+	icount->buf_overrun = cnow.buf_overrun;
+	return 0;
+}
+
 /* mgsl_ioctl()	Service an IOCTL request
  * 	
  * Arguments:
@@ -2949,7 +2981,7 @@ static int mgsl_ioctl(struct tty_struct *tty, struct file * file,
 		return -ENODEV;
 
 	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
-	    (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
+	    (cmd != TIOCMIWAIT)) {
 		if (tty->flags & (1 << TTY_IO_ERROR))
 		    return -EIO;
 	}
@@ -2959,11 +2991,7 @@ static int mgsl_ioctl(struct tty_struct *tty, struct file * file,
 
 static int mgsl_ioctl_common(struct mgsl_struct *info, unsigned int cmd, unsigned long arg)
 {
-	int error;
-	struct mgsl_icount cnow;	/* kernel counter temps */
 	void __user *argp = (void __user *)arg;
-	struct serial_icounter_struct __user *p_cuser;	/* user space */
-	unsigned long flags;
 	
 	switch (cmd) {
 		case MGSL_IOCGPARAMS:
@@ -2992,40 +3020,6 @@ static int mgsl_ioctl_common(struct mgsl_struct *info, unsigned int cmd, unsigne
 		case TIOCMIWAIT:
 			return modem_input_wait(info,(int)arg);
 
-		/* 
-		 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
-		 * Return: write counters to the user passed counter struct
-		 * NB: both 1->0 and 0->1 transitions are counted except for
-		 *     RI where only 0->1 is counted.
-		 */
-		case TIOCGICOUNT:
-			spin_lock_irqsave(&info->irq_spinlock,flags);
-			cnow = info->icount;
-			spin_unlock_irqrestore(&info->irq_spinlock,flags);
-			p_cuser = argp;
-			PUT_USER(error,cnow.cts, &p_cuser->cts);
-			if (error) return error;
-			PUT_USER(error,cnow.dsr, &p_cuser->dsr);
-			if (error) return error;
-			PUT_USER(error,cnow.rng, &p_cuser->rng);
-			if (error) return error;
-			PUT_USER(error,cnow.dcd, &p_cuser->dcd);
-			if (error) return error;
-			PUT_USER(error,cnow.rx, &p_cuser->rx);
-			if (error) return error;
-			PUT_USER(error,cnow.tx, &p_cuser->tx);
-			if (error) return error;
-			PUT_USER(error,cnow.frame, &p_cuser->frame);
-			if (error) return error;
-			PUT_USER(error,cnow.overrun, &p_cuser->overrun);
-			if (error) return error;
-			PUT_USER(error,cnow.parity, &p_cuser->parity);
-			if (error) return error;
-			PUT_USER(error,cnow.brk, &p_cuser->brk);
-			if (error) return error;
-			PUT_USER(error,cnow.buf_overrun, &p_cuser->buf_overrun);
-			if (error) return error;
-			return 0;
 		default:
 			return -ENOIOCTLCMD;
 	}
@@ -4328,6 +4322,7 @@ static const struct tty_operations mgsl_ops = {
 	.hangup = mgsl_hangup,
 	.tiocmget = tiocmget,
 	.tiocmset = tiocmset,
+	.get_icount = msgl_get_icount,
 	.proc_fops = &mgsl_proc_fops,
 };
 
diff --git a/drivers/char/synclink_gt.c b/drivers/char/synclink_gt.c
index e63b830c86c..1746d91205f 100644
--- a/drivers/char/synclink_gt.c
+++ b/drivers/char/synclink_gt.c
@@ -1032,9 +1032,6 @@ static int ioctl(struct tty_struct *tty, struct file *file,
 		 unsigned int cmd, unsigned long arg)
 {
 	struct slgt_info *info = tty->driver_data;
-	struct mgsl_icount cnow;	/* kernel counter temps */
-	struct serial_icounter_struct __user *p_cuser;	/* user space */
-	unsigned long flags;
 	void __user *argp = (void __user *)arg;
 	int ret;
 
@@ -1043,7 +1040,7 @@ static int ioctl(struct tty_struct *tty, struct file *file,
 	DBGINFO(("%s ioctl() cmd=%08X\n", info->device_name, cmd));
 
 	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
-	    (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
+	    (cmd != TIOCMIWAIT)) {
 		if (tty->flags & (1 << TTY_IO_ERROR))
 		    return -EIO;
 	}
@@ -1053,24 +1050,6 @@ static int ioctl(struct tty_struct *tty, struct file *file,
 		return wait_mgsl_event(info, argp);
 	case TIOCMIWAIT:
 		return modem_input_wait(info,(int)arg);
-	case TIOCGICOUNT:
-		spin_lock_irqsave(&info->lock,flags);
-		cnow = info->icount;
-		spin_unlock_irqrestore(&info->lock,flags);
-		p_cuser = argp;
-		if (put_user(cnow.cts, &p_cuser->cts) ||
-		    put_user(cnow.dsr, &p_cuser->dsr) ||
-		    put_user(cnow.rng, &p_cuser->rng) ||
-		    put_user(cnow.dcd, &p_cuser->dcd) ||
-		    put_user(cnow.rx, &p_cuser->rx) ||
-		    put_user(cnow.tx, &p_cuser->tx) ||
-		    put_user(cnow.frame, &p_cuser->frame) ||
-		    put_user(cnow.overrun, &p_cuser->overrun) ||
-		    put_user(cnow.parity, &p_cuser->parity) ||
-		    put_user(cnow.brk, &p_cuser->brk) ||
-		    put_user(cnow.buf_overrun, &p_cuser->buf_overrun))
-			return -EFAULT;
-		return 0;
 	case MGSL_IOCSGPIO:
 		return set_gpio(info, argp);
 	case MGSL_IOCGGPIO:
@@ -1117,6 +1096,33 @@ static int ioctl(struct tty_struct *tty, struct file *file,
 	return ret;
 }
 
+static int get_icount(struct tty_struct *tty,
+				struct serial_icounter_struct *icount)
+
+{
+	struct slgt_info *info = tty->driver_data;
+	struct mgsl_icount cnow;	/* kernel counter temps */
+	unsigned long flags;
+
+	spin_lock_irqsave(&info->lock,flags);
+	cnow = info->icount;
+	spin_unlock_irqrestore(&info->lock,flags);
+
+	icount->cts = cnow.cts;
+	icount->dsr = cnow.dsr;
+	icount->rng = cnow.rng;
+	icount->dcd = cnow.dcd;
+	icount->rx = cnow.rx;
+	icount->tx = cnow.tx;
+	icount->frame = cnow.frame;
+	icount->overrun = cnow.overrun;
+	icount->parity = cnow.parity;
+	icount->brk = cnow.brk;
+	icount->buf_overrun = cnow.buf_overrun;
+
+	return 0;
+}
+
 /*
  * support for 32 bit ioctl calls on 64 bit systems
  */
@@ -1206,10 +1212,6 @@ static long slgt_compat_ioctl(struct tty_struct *tty, struct file *file,
 	case MGSL_IOCSGPIO:
 	case MGSL_IOCGGPIO:
 	case MGSL_IOCWAITGPIO:
-	case TIOCGICOUNT:
-		rc = ioctl(tty, file, cmd, (unsigned long)(compat_ptr(arg)));
-		break;
-
 	case MGSL_IOCSTXIDLE:
 	case MGSL_IOCTXENABLE:
 	case MGSL_IOCRXENABLE:
@@ -3642,6 +3644,7 @@ static const struct tty_operations ops = {
 	.hangup = hangup,
 	.tiocmget = tiocmget,
 	.tiocmset = tiocmset,
+	.get_icount = get_icount,
 	.proc_fops = &synclink_gt_proc_fops,
 };
 
diff --git a/drivers/char/synclinkmp.c b/drivers/char/synclinkmp.c
index e56caf7d82a..2f9eb4b0dec 100644
--- a/drivers/char/synclinkmp.c
+++ b/drivers/char/synclinkmp.c
@@ -1258,10 +1258,6 @@ static int ioctl(struct tty_struct *tty, struct file *file,
 		 unsigned int cmd, unsigned long arg)
 {
 	SLMP_INFO *info = tty->driver_data;
-	int error;
-	struct mgsl_icount cnow;	/* kernel counter temps */
-	struct serial_icounter_struct __user *p_cuser;	/* user space */
-	unsigned long flags;
 	void __user *argp = (void __user *)arg;
 
 	if (debug_level >= DEBUG_LEVEL_INFO)
@@ -1272,7 +1268,7 @@ static int ioctl(struct tty_struct *tty, struct file *file,
 		return -ENODEV;
 
 	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
-	    (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
+	    (cmd != TIOCMIWAIT)) {
 		if (tty->flags & (1 << TTY_IO_ERROR))
 		    return -EIO;
 	}
@@ -1310,40 +1306,38 @@ static int ioctl(struct tty_struct *tty, struct file *file,
 		 * NB: both 1->0 and 0->1 transitions are counted except for
 		 *     RI where only 0->1 is counted.
 		 */
-	case TIOCGICOUNT:
-		spin_lock_irqsave(&info->lock,flags);
-		cnow = info->icount;
-		spin_unlock_irqrestore(&info->lock,flags);
-		p_cuser = argp;
-		PUT_USER(error,cnow.cts, &p_cuser->cts);
-		if (error) return error;
-		PUT_USER(error,cnow.dsr, &p_cuser->dsr);
-		if (error) return error;
-		PUT_USER(error,cnow.rng, &p_cuser->rng);
-		if (error) return error;
-		PUT_USER(error,cnow.dcd, &p_cuser->dcd);
-		if (error) return error;
-		PUT_USER(error,cnow.rx, &p_cuser->rx);
-		if (error) return error;
-		PUT_USER(error,cnow.tx, &p_cuser->tx);
-		if (error) return error;
-		PUT_USER(error,cnow.frame, &p_cuser->frame);
-		if (error) return error;
-		PUT_USER(error,cnow.overrun, &p_cuser->overrun);
-		if (error) return error;
-		PUT_USER(error,cnow.parity, &p_cuser->parity);
-		if (error) return error;
-		PUT_USER(error,cnow.brk, &p_cuser->brk);
-		if (error) return error;
-		PUT_USER(error,cnow.buf_overrun, &p_cuser->buf_overrun);
-		if (error) return error;
-		return 0;
 	default:
 		return -ENOIOCTLCMD;
 	}
 	return 0;
 }
 
+static int get_icount(struct tty_struct *tty,
+				struct serial_icounter_struct *icount)
+{
+	SLMP_INFO *info = tty->driver_data;
+	struct mgsl_icount cnow;	/* kernel counter temps */
+	unsigned long flags;
+
+	spin_lock_irqsave(&info->lock,flags);
+	cnow = info->icount;
+	spin_unlock_irqrestore(&info->lock,flags);
+
+	icount->cts = cnow.cts;
+	icount->dsr = cnow.dsr;
+	icount->rng = cnow.rng;
+	icount->dcd = cnow.dcd;
+	icount->rx = cnow.rx;
+	icount->tx = cnow.tx;
+	icount->frame = cnow.frame;
+	icount->overrun = cnow.overrun;
+	icount->parity = cnow.parity;
+	icount->brk = cnow.brk;
+	icount->buf_overrun = cnow.buf_overrun;
+
+	return 0;
+}
+
 /*
  * /proc fs routines....
  */
@@ -3909,6 +3903,7 @@ static const struct tty_operations ops = {
 	.hangup = hangup,
 	.tiocmget = tiocmget,
 	.tiocmset = tiocmset,
+	.get_icount = get_icount,
 	.proc_fops = &synclinkmp_proc_fops,
 };
 
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index 613c852ee0f..c05c5af5aa0 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -96,6 +96,7 @@
 #include <linux/bitops.h>
 #include <linux/delay.h>
 #include <linux/seq_file.h>
+#include <linux/serial.h>
 
 #include <linux/uaccess.h>
 #include <asm/system.h>
@@ -183,6 +184,8 @@ struct tty_struct *alloc_tty_struct(void)
 
 void free_tty_struct(struct tty_struct *tty)
 {
+	if (tty->dev)
+		put_device(tty->dev);
 	kfree(tty->write_buf);
 	tty_buffer_free_all(tty);
 	kfree(tty);
@@ -194,12 +197,13 @@ static inline struct tty_struct *file_tty(struct file *file)
 }
 
 /* Associate a new file with the tty structure */
-void tty_add_file(struct tty_struct *tty, struct file *file)
+int tty_add_file(struct tty_struct *tty, struct file *file)
 {
 	struct tty_file_private *priv;
 
-	/* XXX: must implement proper error handling in callers */
-	priv = kmalloc(sizeof(*priv), GFP_KERNEL|__GFP_NOFAIL);
+	priv = kmalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
 
 	priv->tty = tty;
 	priv->file = file;
@@ -208,6 +212,8 @@ void tty_add_file(struct tty_struct *tty, struct file *file)
 	spin_lock(&tty_files_lock);
 	list_add(&priv->list, &tty->tty_files);
 	spin_unlock(&tty_files_lock);
+
+	return 0;
 }
 
 /* Delete file from its tty */
@@ -1875,7 +1881,11 @@ got_driver:
 		return PTR_ERR(tty);
 	}
 
-	tty_add_file(tty, filp);
+	retval = tty_add_file(tty, filp);
+	if (retval) {
+		tty_unlock();
+		return retval;
+	}
 
 	check_tty_count(tty, "tty_open");
 	if (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
@@ -2502,6 +2512,20 @@ static int tty_tiocmset(struct tty_struct *tty, struct file *file, unsigned int
 	return tty->ops->tiocmset(tty, file, set, clear);
 }
 
+static int tty_tiocgicount(struct tty_struct *tty, void __user *arg)
+{
+	int retval = -EINVAL;
+	struct serial_icounter_struct icount;
+	memset(&icount, 0, sizeof(icount));
+	if (tty->ops->get_icount)
+		retval = tty->ops->get_icount(tty, &icount);
+	if (retval != 0)
+		return retval;
+	if (copy_to_user(arg, &icount, sizeof(icount)))
+		return -EFAULT;
+	return 0;
+}
+
 struct tty_struct *tty_pair_get_tty(struct tty_struct *tty)
 {
 	if (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
@@ -2622,6 +2646,12 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 	case TIOCMBIC:
 	case TIOCMBIS:
 		return tty_tiocmset(tty, file, cmd, p);
+	case TIOCGICOUNT:
+		retval = tty_tiocgicount(tty, p);
+		/* For the moment allow fall through to the old method */
+        	if (retval != -EINVAL)
+			return retval;
+		break;
 	case TCFLSH:
 		switch (arg) {
 		case TCIFLUSH:
@@ -2783,6 +2813,20 @@ void do_SAK(struct tty_struct *tty)
 
 EXPORT_SYMBOL(do_SAK);
 
+static int dev_match_devt(struct device *dev, void *data)
+{
+	dev_t *devt = data;
+	return dev->devt == *devt;
+}
+
+/* Must put_device() after it's unused! */
+static struct device *tty_get_device(struct tty_struct *tty)
+{
+	dev_t devt = tty_devnum(tty);
+	return class_find_device(tty_class, NULL, &devt, dev_match_devt);
+}
+
+
 /**
  *	initialize_tty_struct
  *	@tty: tty to initialize
@@ -2823,6 +2867,7 @@ void initialize_tty_struct(struct tty_struct *tty,
 	tty->ops = driver->ops;
 	tty->index = idx;
 	tty_line_name(driver, idx, tty->name);
+	tty->dev = tty_get_device(tty);
 }
 
 /**
@@ -2980,6 +3025,7 @@ int tty_register_driver(struct tty_driver *driver)
 	int i;
 	dev_t dev;
 	void **p = NULL;
+	struct device *d;
 
 	if (!(driver->flags & TTY_DRIVER_DEVPTS_MEM) && driver->num) {
 		p = kzalloc(driver->num * 2 * sizeof(void *), GFP_KERNEL);
@@ -3027,12 +3073,31 @@ int tty_register_driver(struct tty_driver *driver)
 	mutex_unlock(&tty_mutex);
 
 	if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV)) {
-		for (i = 0; i < driver->num; i++)
-		    tty_register_device(driver, i, NULL);
+		for (i = 0; i < driver->num; i++) {
+			d = tty_register_device(driver, i, NULL);
+			if (IS_ERR(d)) {
+				error = PTR_ERR(d);
+				goto err;
+			}
+		}
 	}
 	proc_tty_register_driver(driver);
 	driver->flags |= TTY_DRIVER_INSTALLED;
 	return 0;
+
+err:
+	for (i--; i >= 0; i--)
+		tty_unregister_device(driver, i);
+
+	mutex_lock(&tty_mutex);
+	list_del(&driver->tty_drivers);
+	mutex_unlock(&tty_mutex);
+
+	unregister_chrdev_region(dev, driver->num);
+	driver->ttys = NULL;
+	driver->termios = NULL;
+	kfree(p);
+	return error;
 }
 
 EXPORT_SYMBOL(tty_register_driver);
diff --git a/drivers/char/ttyprintk.c b/drivers/char/ttyprintk.c
new file mode 100644
index 00000000000..c40c1612c8a
--- /dev/null
+++ b/drivers/char/ttyprintk.c
@@ -0,0 +1,225 @@
+/*
+ *  linux/drivers/char/ttyprintk.c
+ *
+ *  Copyright (C) 2010  Samo Pogacnik
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the smems of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ */
+
+/*
+ * This pseudo device allows user to make printk messages. It is possible
+ * to store "console" messages inline with kernel messages for better analyses
+ * of the boot process, for example.
+ */
+
+#include <linux/device.h>
+#include <linux/serial.h>
+#include <linux/tty.h>
+
+struct ttyprintk_port {
+	struct tty_port port;
+	struct mutex port_write_mutex;
+};
+
+static struct ttyprintk_port tpk_port;
+
+/*
+ * Our simple preformatting supports transparent output of (time-stamped)
+ * printk messages (also suitable for logging service):
+ * - any cr is replaced by nl
+ * - adds a ttyprintk source tag in front of each line
+ * - too long message is fragmeted, with '\'nl between fragments
+ * - TPK_STR_SIZE isn't really the write_room limiting factor, bcause
+ *   it is emptied on the fly during preformatting.
+ */
+#define TPK_STR_SIZE 508 /* should be bigger then max expected line length */
+#define TPK_MAX_ROOM 4096 /* we could assume 4K for instance */
+static const char *tpk_tag = "[U] "; /* U for User */
+static int tpk_curr;
+
+static int tpk_printk(const unsigned char *buf, int count)
+{
+	static char tmp[TPK_STR_SIZE + 4];
+	int i = tpk_curr;
+
+	if (buf == NULL) {
+		/* flush tmp[] */
+		if (tpk_curr > 0) {
+			/* non nl or cr terminated message - add nl */
+			tmp[tpk_curr + 0] = '\n';
+			tmp[tpk_curr + 1] = '\0';
+			printk(KERN_INFO "%s%s", tpk_tag, tmp);
+			tpk_curr = 0;
+		}
+		return i;
+	}
+
+	for (i = 0; i < count; i++) {
+		tmp[tpk_curr] = buf[i];
+		if (tpk_curr < TPK_STR_SIZE) {
+			switch (buf[i]) {
+			case '\r':
+				/* replace cr with nl */
+				tmp[tpk_curr + 0] = '\n';
+				tmp[tpk_curr + 1] = '\0';
+				printk(KERN_INFO "%s%s", tpk_tag, tmp);
+				tpk_curr = 0;
+				if (buf[i + 1] == '\n')
+					i++;
+				break;
+			case '\n':
+				tmp[tpk_curr + 1] = '\0';
+				printk(KERN_INFO "%s%s", tpk_tag, tmp);
+				tpk_curr = 0;
+				break;
+			default:
+				tpk_curr++;
+			}
+		} else {
+			/* end of tmp buffer reached: cut the message in two */
+			tmp[tpk_curr + 1] = '\\';
+			tmp[tpk_curr + 2] = '\n';
+			tmp[tpk_curr + 3] = '\0';
+			printk(KERN_INFO "%s%s", tpk_tag, tmp);
+			tpk_curr = 0;
+		}
+	}
+
+	return count;
+}
+
+/*
+ * TTY operations open function.
+ */
+static int tpk_open(struct tty_struct *tty, struct file *filp)
+{
+	tty->driver_data = &tpk_port;
+
+	return tty_port_open(&tpk_port.port, tty, filp);
+}
+
+/*
+ * TTY operations close function.
+ */
+static void tpk_close(struct tty_struct *tty, struct file *filp)
+{
+	struct ttyprintk_port *tpkp = tty->driver_data;
+
+	mutex_lock(&tpkp->port_write_mutex);
+	/* flush tpk_printk buffer */
+	tpk_printk(NULL, 0);
+	mutex_unlock(&tpkp->port_write_mutex);
+
+	tty_port_close(&tpkp->port, tty, filp);
+}
+
+/*
+ * TTY operations write function.
+ */
+static int tpk_write(struct tty_struct *tty,
+		const unsigned char *buf, int count)
+{
+	struct ttyprintk_port *tpkp = tty->driver_data;
+	int ret;
+
+
+	/* exclusive use of tpk_printk within this tty */
+	mutex_lock(&tpkp->port_write_mutex);
+	ret = tpk_printk(buf, count);
+	mutex_unlock(&tpkp->port_write_mutex);
+
+	return ret;
+}
+
+/*
+ * TTY operations write_room function.
+ */
+static int tpk_write_room(struct tty_struct *tty)
+{
+	return TPK_MAX_ROOM;
+}
+
+/*
+ * TTY operations ioctl function.
+ */
+static int tpk_ioctl(struct tty_struct *tty, struct file *file,
+			unsigned int cmd, unsigned long arg)
+{
+	struct ttyprintk_port *tpkp = tty->driver_data;
+
+	if (!tpkp)
+		return -EINVAL;
+
+	switch (cmd) {
+	/* Stop TIOCCONS */
+	case TIOCCONS:
+		return -EOPNOTSUPP;
+	default:
+		return -ENOIOCTLCMD;
+	}
+	return 0;
+}
+
+static const struct tty_operations ttyprintk_ops = {
+	.open = tpk_open,
+	.close = tpk_close,
+	.write = tpk_write,
+	.write_room = tpk_write_room,
+	.ioctl = tpk_ioctl,
+};
+
+struct tty_port_operations null_ops = { };
+
+static struct tty_driver *ttyprintk_driver;
+
+static int __init ttyprintk_init(void)
+{
+	int ret = -ENOMEM;
+	void *rp;
+
+	ttyprintk_driver = alloc_tty_driver(1);
+	if (!ttyprintk_driver)
+		return ret;
+
+	ttyprintk_driver->owner = THIS_MODULE;
+	ttyprintk_driver->driver_name = "ttyprintk";
+	ttyprintk_driver->name = "ttyprintk";
+	ttyprintk_driver->major = TTYAUX_MAJOR;
+	ttyprintk_driver->minor_start = 3;
+	ttyprintk_driver->num = 1;
+	ttyprintk_driver->type = TTY_DRIVER_TYPE_CONSOLE;
+	ttyprintk_driver->init_termios = tty_std_termios;
+	ttyprintk_driver->init_termios.c_oflag = OPOST | OCRNL | ONOCR | ONLRET;
+	ttyprintk_driver->flags = TTY_DRIVER_RESET_TERMIOS |
+		TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
+	tty_set_operations(ttyprintk_driver, &ttyprintk_ops);
+
+	ret = tty_register_driver(ttyprintk_driver);
+	if (ret < 0) {
+		printk(KERN_ERR "Couldn't register ttyprintk driver\n");
+		goto error;
+	}
+
+	/* create our unnumbered device */
+	rp = device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 3), NULL,
+				ttyprintk_driver->name);
+	if (IS_ERR(rp)) {
+		printk(KERN_ERR "Couldn't create ttyprintk device\n");
+		ret = PTR_ERR(rp);
+		goto error;
+	}
+
+	tty_port_init(&tpk_port.port);
+	tpk_port.port.ops = &null_ops;
+	mutex_init(&tpk_port.port_write_mutex);
+
+	return 0;
+
+error:
+	put_tty_driver(ttyprintk_driver);
+	ttyprintk_driver = NULL;
+	return ret;
+}
+module_init(ttyprintk_init);
diff --git a/drivers/char/vc_screen.c b/drivers/char/vc_screen.c
index bcce46c96b8..273ab44cc91 100644
--- a/drivers/char/vc_screen.c
+++ b/drivers/char/vc_screen.c
@@ -35,6 +35,12 @@
 #include <linux/console.h>
 #include <linux/device.h>
 #include <linux/smp_lock.h>
+#include <linux/sched.h>
+#include <linux/fs.h>
+#include <linux/poll.h>
+#include <linux/signal.h>
+#include <linux/slab.h>
+#include <linux/notifier.h>
 
 #include <asm/uaccess.h>
 #include <asm/byteorder.h>
@@ -45,6 +51,86 @@
 #undef addr
 #define HEADER_SIZE	4
 
+struct vcs_poll_data {
+	struct notifier_block notifier;
+	unsigned int cons_num;
+	bool seen_last_update;
+	wait_queue_head_t waitq;
+	struct fasync_struct *fasync;
+};
+
+static int
+vcs_notifier(struct notifier_block *nb, unsigned long code, void *_param)
+{
+	struct vt_notifier_param *param = _param;
+	struct vc_data *vc = param->vc;
+	struct vcs_poll_data *poll =
+		container_of(nb, struct vcs_poll_data, notifier);
+	int currcons = poll->cons_num;
+
+	if (code != VT_UPDATE)
+		return NOTIFY_DONE;
+
+	if (currcons == 0)
+		currcons = fg_console;
+	else
+		currcons--;
+	if (currcons != vc->vc_num)
+		return NOTIFY_DONE;
+
+	poll->seen_last_update = false;
+	wake_up_interruptible(&poll->waitq);
+	kill_fasync(&poll->fasync, SIGIO, POLL_IN);
+	return NOTIFY_OK;
+}
+
+static void
+vcs_poll_data_free(struct vcs_poll_data *poll)
+{
+	unregister_vt_notifier(&poll->notifier);
+	kfree(poll);
+}
+
+static struct vcs_poll_data *
+vcs_poll_data_get(struct file *file)
+{
+	struct vcs_poll_data *poll = file->private_data;
+
+	if (poll)
+		return poll;
+
+	poll = kzalloc(sizeof(*poll), GFP_KERNEL);
+	if (!poll)
+		return NULL;
+	poll->cons_num = iminor(file->f_path.dentry->d_inode) & 127;
+	init_waitqueue_head(&poll->waitq);
+	poll->notifier.notifier_call = vcs_notifier;
+	if (register_vt_notifier(&poll->notifier) != 0) {
+		kfree(poll);
+		return NULL;
+	}
+
+	/*
+	 * This code may be called either through ->poll() or ->fasync().
+	 * If we have two threads using the same file descriptor, they could
+	 * both enter this function, both notice that the structure hasn't
+	 * been allocated yet and go ahead allocating it in parallel, but
+	 * only one of them must survive and be shared otherwise we'd leak
+	 * memory with a dangling notifier callback.
+	 */
+	spin_lock(&file->f_lock);
+	if (!file->private_data) {
+		file->private_data = poll;
+	} else {
+		/* someone else raced ahead of us */
+		vcs_poll_data_free(poll);
+		poll = file->private_data;
+	}
+	spin_unlock(&file->f_lock);
+
+	return poll;
+}
+
 static int
 vcs_size(struct inode *inode)
 {
@@ -102,6 +188,7 @@ vcs_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
 	struct inode *inode = file->f_path.dentry->d_inode;
 	unsigned int currcons = iminor(inode);
 	struct vc_data *vc;
+	struct vcs_poll_data *poll;
 	long pos;
 	long viewed, attr, read;
 	int col, maxcol;
@@ -134,6 +221,9 @@ vcs_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
 	ret = -EINVAL;
 	if (pos < 0)
 		goto unlock_out;
+	poll = file->private_data;
+	if (count && poll)
+		poll->seen_last_update = true;
 	read = 0;
 	ret = 0;
 	while (count) {
@@ -448,6 +538,8 @@ vcs_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
 	}
 	*ppos += written;
 	ret = written;
+	if (written)
+		vcs_scr_updated(vc);
 
 unlock_out:
 	release_console_sem();
@@ -457,6 +549,37 @@ unlock_out:
 	return ret;
 }
 
+static unsigned int
+vcs_poll(struct file *file, poll_table *wait)
+{
+	struct vcs_poll_data *poll = vcs_poll_data_get(file);
+	int ret = 0;
+
+	if (poll) {
+		poll_wait(file, &poll->waitq, wait);
+		if (!poll->seen_last_update)
+			ret = POLLIN | POLLRDNORM;
+	}
+	return ret;
+}
+
+static int
+vcs_fasync(int fd, struct file *file, int on)
+{
+	struct vcs_poll_data *poll = file->private_data;
+
+	if (!poll) {
+		/* don't allocate anything if all we want is disable fasync */
+		if (!on)
+			return 0;
+		poll = vcs_poll_data_get(file);
+		if (!poll)
+			return -ENOMEM;
+	}
+
+	return fasync_helper(fd, file, on, &poll->fasync);
+}
+
 static int
 vcs_open(struct inode *inode, struct file *filp)
 {
@@ -470,11 +593,23 @@ vcs_open(struct inode *inode, struct file *filp)
 	return ret;
 }
 
+static int vcs_release(struct inode *inode, struct file *file)
+{
+	struct vcs_poll_data *poll = file->private_data;
+
+	if (poll)
+		vcs_poll_data_free(poll);
+	return 0;
+}
+
 static const struct file_operations vcs_fops = {
 	.llseek		= vcs_lseek,
 	.read		= vcs_read,
 	.write		= vcs_write,
+	.poll		= vcs_poll,
+	.fasync		= vcs_fasync,
 	.open		= vcs_open,
+	.release	= vcs_release,
 };
 
 static struct class *vc_class;
diff --git a/drivers/char/vt.c b/drivers/char/vt.c
index 281aada7b4a..a8ec48ed14d 100644
--- a/drivers/char/vt.c
+++ b/drivers/char/vt.c
@@ -4182,6 +4182,11 @@ void vcs_scr_writew(struct vc_data *vc, u16 val, u16 *org)
 	}
 }
 
+void vcs_scr_updated(struct vc_data *vc)
+{
+	notify_update(vc);
+}
+
 /*
  *	Visible symbols for modules
  */