Merge branch 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/…

…git/gregkh/tty-2.6

* 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: (36 commits)
  serial: apbuart: Fixup apbuart_console_init()
  TTY: Add tty ioctl to figure device node of the system console.
  tty: add 'active' sysfs attribute to tty0 and console device
  drivers: serial: apbuart: Handle OF failures gracefully
  Serial: Avoid unbalanced IRQ wake disable during resume
  tty: fix typos/errors in tty_driver.h comments
  pch_uart : fix warnings for 64bit compile
  8250: fix uninitialized FIFOs
  ip2: fix compiler warning on ip2main_pci_tbl
  specialix: fix compiler warning on specialix_pci_tbl
  rocket: fix compiler warning on rocket_pci_ids
  8250: add a UPIO_DWAPB32 for 32 bit accesses
  8250: use container_of() instead of casting
  serial: omap-serial: Add support for kernel debugger
  serial: fix pch_uart kconfig & build
  drivers: char: hvc: add arm JTAG DCC console support
  RS485 documentation: add 16C950 UART description
  serial: ifx6x60: fix memory leak
  serial: ifx6x60: free IRQ on error
  Serial: EG20T: add PCH_UART driver
  ...

Fixed up conflicts in drivers/serial/apbuart.c with evil merge that
makes the code look fairly sane (unlike either side).

Documentation/ABI/testing/sysfs-tty

@@ -0,0 +1,19 @@
+What:		/sys/class/tty/console/active
+Date:		Nov 2010
+Contact:	Kay Sievers <kay.sievers@vrfy.org>
+Description:
+		 Shows the list of currently configured
+		 console devices, like 'tty1 ttyS0'.
+		 The last entry in the file is the active
+		 device connected to /dev/console.
+		 The file supports poll() to detect virtual
+		 console switches.
+
+What:		/sys/class/tty/tty0/active
+Date:		Nov 2010
+Contact:	Kay Sievers <kay.sievers@vrfy.org>
+Description:
+		 Shows the currently active virtual console
+		 device, like 'tty1'.
+		 The file supports poll() to detect virtual
+		 console switches.

Documentation/filesystems/proc.txt

@@ -1181,6 +1181,30 @@ Table 1-12: Files in /proc/fs/ext4/<devname>
  mb_groups       details of multiblock allocator buddy cache of free blocks
 ..............................................................................
 
+2.0 /proc/consoles
+------------------
+Shows registered system console lines.
+
+To see which character device lines are currently used for the system console
+/dev/console, you may simply look into the file /proc/consoles:
+
+  > cat /proc/consoles
+  tty0                 -WU (ECp)       4:7
+  ttyS0                -W- (Ep)        4:64
+
+The columns are:
+
+  device               name of the device
+  operations           R = can do read operations
+                       W = can do write operations
+                       U = can do unblank
+  flags                E = it is enabled
+                       C = it is prefered console
+                       B = it is primary boot console
+                       p = it is used for printk buffer
+                       b = it is not a TTY but a Braille device
+                       a = it is safe to use when cpu is offline
+  major:minor          major and minor number of the device separated by a colon
 
 ------------------------------------------------------------------------------
 Summary

Documentation/serial/00-INDEX

@@ -14,6 +14,8 @@ riscom8.txt
 	- notes on using the RISCom/8 multi-port serial driver.
 rocket.txt
 	- info on the Comtrol RocketPort multiport serial driver.
+serial-rs485.txt
+	- info about RS485 structures and support in the kernel.
 specialix.txt
 	- info on hardware/driver for specialix IO8+ multiport serial card.
 stallion.txt

Documentation/serial/serial-rs485.txt

@@ -0,0 +1,120 @@
+                        RS485 SERIAL COMMUNICATIONS
+
+1. INTRODUCTION
+
+   EIA-485, also known as TIA/EIA-485 or RS-485, is a standard defining the
+   electrical characteristics of drivers and receivers for use in balanced
+   digital multipoint systems.
+   This standard is widely used for communications in industrial automation
+   because it can be used effectively over long distances and in electrically
+   noisy environments.
+
+2. HARDWARE-RELATED CONSIDERATIONS
+
+   Some CPUs/UARTs (e.g., Atmel AT91 or 16C950 UART) contain a built-in
+   half-duplex mode capable of automatically controlling line direction by
+   toggling RTS or DTR signals. That can be used to control external
+   half-duplex hardware like an RS485 transceiver or any RS232-connected
+   half-duplex devices like some modems.
+
+   For these microcontrollers, the Linux driver should be made capable of
+   working in both modes, and proper ioctls (see later) should be made
+   available at user-level to allow switching from one mode to the other, and
+   vice versa.
+
+3. DATA STRUCTURES ALREADY AVAILABLE IN THE KERNEL
+
+   The Linux kernel provides the serial_rs485 structure (see [1]) to handle
+   RS485 communications. This data structure is used to set and configure RS485
+   parameters in the platform data and in ioctls.
+
+   Any driver for devices capable of working both as RS232 and RS485 should
+   provide at least the following ioctls:
+
+    - TIOCSRS485 (typically associated with number 0x542F). This ioctl is used
+      to enable/disable RS485 mode from user-space
+
+    - TIOCGRS485 (typically associated with number 0x542E). This ioctl is used
+      to get RS485 mode from kernel-space (i.e., driver) to user-space.
+
+   In other words, the serial driver should contain a code similar to the next
+   one:
+
+	static struct uart_ops atmel_pops = {
+		/* ... */
+		.ioctl		= handle_ioctl,
+	};
+
+	static int handle_ioctl(struct uart_port *port,
+		unsigned int cmd,
+		unsigned long arg)
+	{
+		struct serial_rs485 rs485conf;
+
+		switch (cmd) {
+		case TIOCSRS485:
+			if (copy_from_user(&rs485conf,
+				(struct serial_rs485 *) arg,
+				sizeof(rs485conf)))
+					return -EFAULT;
+
+			/* ... */
+			break;
+
+		case TIOCGRS485:
+			if (copy_to_user((struct serial_rs485 *) arg,
+				...,
+				sizeof(rs485conf)))
+					return -EFAULT;
+			/* ... */
+			break;
+
+		/* ... */
+		}
+	}
+
+
+4. USAGE FROM USER-LEVEL
+
+   From user-level, RS485 configuration can be get/set using the previous
+   ioctls. For instance, to set RS485 you can use the following code:
+
+	#include <linux/serial.h>
+
+	/* Driver-specific ioctls: */
+	#define TIOCGRS485      0x542E
+	#define TIOCSRS485      0x542F
+
+	/* Open your specific device (e.g., /dev/mydevice): */
+	int fd = open ("/dev/mydevice", O_RDWR);
+	if (fd < 0) {
+		/* Error handling. See errno. */
+	}
+
+	struct serial_rs485 rs485conf;
+
+	/* Set RS485 mode: */
+	rs485conf.flags |= SER_RS485_ENABLED;
+
+	/* Set rts delay before send, if needed: */
+	rs485conf.flags |= SER_RS485_RTS_BEFORE_SEND;
+	rs485conf.delay_rts_before_send = ...;
+
+	/* Set rts delay after send, if needed: */
+	rs485conf.flags |= SER_RS485_RTS_AFTER_SEND;
+	rs485conf.delay_rts_after_send = ...;
+
+	if (ioctl (fd, TIOCSRS485, &rs485conf) < 0) {
+		/* Error handling. See errno. */
+	}
+
+	/* Use read() and write() syscalls here... */
+
+	/* Close the device when finished: */
+	if (close (fd) < 0) {
+		/* Error handling. See errno. */
+	}
+
+5. REFERENCES
+
+ [1]	include/linux/serial.h

arch/alpha/include/asm/ioctls.h

@@ -92,6 +92,7 @@
 #define TIOCGSID	0x5429  /* Return the session ID of FD */
 #define TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TIOCGDEV	_IOR('T',0x32, unsigned int) /* Get primary device node of /dev/console */
 #define TIOCSIG		_IOW('T',0x36, int)  /* Generate signal on Pty slave */
 
 #define TIOCSERCONFIG	0x5453

arch/mips/include/asm/ioctls.h

@@ -83,6 +83,7 @@
 #define TCSETSF2	_IOW('T', 0x2D, struct termios2)
 #define TIOCGPTN	_IOR('T', 0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T', 0x31, int)  /* Lock/unlock Pty */
+#define TIOCGDEV	_IOR('T', 0x32, unsigned int) /* Get primary device node of /dev/console */
 #define TIOCSIG		_IOW('T', 0x36, int)  /* Generate signal on Pty slave */
 
 /* I hope the range from 0x5480 on is free ... */

arch/parisc/include/asm/ioctls.h

@@ -52,6 +52,7 @@
 #define TCSETSF2	_IOW('T',0x2D, struct termios2)
 #define TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TIOCGDEV	_IOR('T',0x32, int)  /* Get primary device node of /dev/console */
 #define TIOCSIG		_IOW('T',0x36, int)  /* Generate signal on Pty slave */
 
 #define FIONCLEX	0x5450  /* these numbers need to be adjusted. */

arch/parisc/kernel/pdc_cons.c

@@ -92,8 +92,6 @@ static int pdc_console_setup(struct console *co, char *options)
 
 static struct timer_list pdc_console_timer;
 
-extern struct console * console_drivers;
-
 static int pdc_console_tty_open(struct tty_struct *tty, struct file *filp)
 {
 
@@ -169,11 +167,13 @@ static int __init pdc_console_tty_driver_init(void)
 	 * It is unregistered if the pdc console was not selected as the
 	 * primary console. */
 
-	struct console *tmp = console_drivers;
+	struct console *tmp;
 
-	for (tmp = console_drivers; tmp; tmp = tmp->next)
+	acquire_console_sem();
+	for_each_console(tmp)
 		if (tmp == &pdc_cons)
 			break;
+	release_console_sem();
 
 	if (!tmp) {
 		printk(KERN_INFO "PDC console driver not registered anymore, not creating %s\n", pdc_cons.name);

arch/powerpc/include/asm/ioctls.h

@@ -94,6 +94,7 @@
 #define TIOCSRS485	0x542f
 #define TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TIOCGDEV	_IOR('T',0x32, unsigned int) /* Get primary device node of /dev/console */
 #define TIOCSIG		_IOW('T',0x36, int)  /* Generate signal on Pty slave */
 
 #define TIOCSERCONFIG	0x5453

arch/sh/include/asm/ioctls.h

@@ -85,6 +85,7 @@
 #define TCSETSF2	_IOW('T', 45, struct termios2)
 #define TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TIOCGDEV	_IOR('T',0x32, unsigned int) /* Get primary device node of /dev/console */
 #define TIOCSIG		_IOW('T',0x36, int)  /* Generate signal on Pty slave */
 
 #define TIOCSERCONFIG	_IO('T', 83) /* 0x5453 */

arch/sparc/include/asm/ioctls.h

@@ -19,6 +19,7 @@
 #define TCSETS2		_IOW('T', 13, struct termios2)
 #define TCSETSW2	_IOW('T', 14, struct termios2)
 #define TCSETSF2	_IOW('T', 15, struct termios2)
+#define TIOCGDEV	_IOR('T',0x32, unsigned int) /* Get primary device node of /dev/console */
 
 /* Note that all the ioctls that are not available in Linux have a 
  * double underscore on the front to: a) avoid some programs to

arch/xtensa/include/asm/ioctls.h

@@ -98,6 +98,7 @@
 #define TCSETSF2	_IOW('T', 45, struct termios2)
 #define TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TIOCGDEV	_IOR('T',0x32, unsigned int) /* Get primary device node of /dev/console */
 #define TIOCSIG		_IOW('T',0x36, int)  /* Generate signal on Pty slave */
 
 #define TIOCSERCONFIG	_IO('T', 83)

drivers/char/Kconfig

@@ -682,6 +682,15 @@ config HVC_UDBG
        select HVC_DRIVER
        default n
 
+config HVC_DCC
+       bool "ARM JTAG DCC console"
+       depends on ARM
+       select HVC_DRIVER
+       help
+         This console uses the JTAG DCC on ARM to create a console under the HVC
+	 driver. This console is used through a JTAG only on ARM. If you don't have
+	 a JTAG then you probably don't want this option.
+
 config VIRTIO_CONSOLE
 	tristate "Virtio console"
 	depends on VIRTIO

drivers/char/Makefile

@@ -34,6 +34,7 @@ obj-$(CONFIG_HVC_CONSOLE)	+= hvc_vio.o hvsi.o
 obj-$(CONFIG_HVC_ISERIES)	+= hvc_iseries.o
 obj-$(CONFIG_HVC_RTAS)		+= hvc_rtas.o
 obj-$(CONFIG_HVC_TILE)		+= hvc_tile.o
+obj-$(CONFIG_HVC_DCC)		+= hvc_dcc.o
 obj-$(CONFIG_HVC_BEAT)		+= hvc_beat.o
 obj-$(CONFIG_HVC_DRIVER)	+= hvc_console.o
 obj-$(CONFIG_HVC_IRQ)		+= hvc_irq.o