Merge tag 'tty-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here's the tty and serial driver patches for 4.2-rc1.

  A number of individual driver updates, some code cleanups, and other
  minor things, full details in the shortlog.

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

* tag 'tty-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (152 commits)
  Doc: serial-rs485.txt: update RS485 driver interface
  Doc: tty.txt: remove mention of the BKL
  MAINTAINERS: tty: add serial docs directory
  serial: sprd: check for NULL after calling devm_clk_get
  serial: 8250_pci: Correct uartclk for xr17v35x expansion chips
  serial: 8250_pci: Add support for 12 port Exar boards
  serial: 8250_uniphier: add bindings document for UniPhier UART
  serial: core: cleanup in uart_get_baud_rate()
  serial: stm32-usart: Add STM32 USART Driver
  tty/serial: kill off set_irq_flags usage
  tty: move linux/gsmmux.h to uapi
  doc: dt: add documentation for nxp,lpc1850-uart
  serial: 8250: add LPC18xx/43xx UART driver
  serial: 8250_uniphier: add UniPhier serial driver
  serial: 8250_dw: support ACPI platforms with integrated DMA engine
  serial: of_serial: check the return value of clk_prepare_enable()
  serial: of_serial: use devm_clk_get() instead of clk_get()
  serial: earlycon: Add support for big-endian MMIO accesses
  serial: sirf: use hrtimer for data rx
  serial: sirf: correct the fifo empty_bit
  ...

1 files changed, 5 insertions, 45 deletions

diff --git a/Documentation/serial/serial-rs485.txt b/Documentation/serial/serial-rs485.txt
index 39dac95422a3..2253b8b45a74 100644
--- a/Documentation/serial/serial-rs485.txt
+++ b/Documentation/serial/serial-rs485.txt
@@ -33,50 +33,10 @@
    the values given by the device tree.
 
    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;
-
-		/* ... */
-		}
-	}
-
+   implement the rs485_config callback in the uart_port structure. The
+   serial_core calls rs485_config to do the device specific part in response
+   to TIOCSRS485 and TIOCGRS485 ioctls (see below). The rs485_config callback
+   receives a pointer to struct serial_rs485.
 
 4. USAGE FROM USER-LEVEL
 
@@ -85,7 +45,7 @@
 
 	#include <linux/serial.h>
 
-	/* Driver-specific ioctls: */
+	/* RS485 ioctls: */
 	#define TIOCGRS485      0x542E
 	#define TIOCSRS485      0x542F