serial: New serial driver MAX310X

This driver is a replacement for a MAX3107 driver with a lot of
improvements and new features.
The main differences from the old version:
- Using the regmap.
- Using devm_XXX-related functions.
- The use of threaded IRQ with IRQF_ONESHOT flag allows the driver to
  the hardware that supports only level IRQ.
- Improved error handling of serial port, improved FIFO handling,
  improved hardware & software flow control.
- Advanced flags allows turn on RS-485 mode (Auto direction control).
- Ability to load multiple instances of drivers.
- Added support for MAX3108.
- GPIO support.
- Driver is quite ready for adding I2C support and support other ICs
  with compatible registers set (MAX3109, MAX14830).
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/Kconfig

@@ -257,12 +257,19 @@ config SERIAL_MAX3100
 	help
 	  MAX3100 chip support
 
-config SERIAL_MAX3107
-	tristate "MAX3107 support"
+config SERIAL_MAX310X
+	bool "MAX310X support"
 	depends on SPI
 	select SERIAL_CORE
+	select REGMAP_SPI if SPI
+	default n
 	help
-	  MAX3107 chip support
+	  This selects support for an advanced UART from Maxim (Dallas).
+	  Supported ICs are MAX3107, MAX3108.
+	  Each IC contains 128 words each of receive and transmit FIFO
+	  that can be controlled through I2C or high-speed SPI.
+
+	  Say Y here if you want to support this ICs.
 
 config SERIAL_DZ
 	bool "DECstation DZ serial driver"

drivers/tty/serial/Makefile

@@ -28,7 +28,7 @@ obj-$(CONFIG_SERIAL_BFIN) += bfin_uart.o
 obj-$(CONFIG_SERIAL_BFIN_SPORT) += bfin_sport_uart.o
 obj-$(CONFIG_SERIAL_SAMSUNG) += samsung.o
 obj-$(CONFIG_SERIAL_MAX3100) += max3100.o
-obj-$(CONFIG_SERIAL_MAX3107) += max3107.o
+obj-$(CONFIG_SERIAL_MAX310X) += max310x.o
 obj-$(CONFIG_SERIAL_IP22_ZILOG) += ip22zilog.o
 obj-$(CONFIG_SERIAL_MUX) += mux.o
 obj-$(CONFIG_SERIAL_68328) += 68328serial.o

include/linux/platform_data/max310x.h

+/*
+ *  Maxim (Dallas) MAX3107/8 serial driver
+ *
+ *  Copyright (C) 2012 Alexander Shiyan <shc_work@mail.ru>
+ *
+ *  Based on max3100.c, by Christian Pellegrin <chripell@evolware.org>
+ *  Based on max3110.c, by Feng Tang <feng.tang@intel.com>
+ *  Based on max3107.c, by Aavamobile
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ */
+
+#ifndef _MAX310X_H_
+#define _MAX310X_H_
+
+/*
+ * Example board initialization data:
+ *
+ * static struct max310x_pdata max3107_pdata = {
+ *	.driver_flags	= MAX310X_EXT_CLK,
+ *	.uart_flags[0]	= MAX310X_ECHO_SUPRESS | MAX310X_AUTO_DIR_CTRL,
+ *	.frequency	= 3686400,
+ *	.gpio_base	= -1,
+ * };
+ *
+ * static struct spi_board_info spi_device_max3107[] = {
+ *	{
+ *		.modalias	= "max3107",
+ *		.irq		= IRQ_EINT3,
+ *		.bus_num	= 1,
+ *		.chip_select	= 1,
+ *		.platform_data	= &max3107_pdata,
+ *	},
+ * };
+ */
+
+#define MAX310X_MAX_UARTS	1
+
+/* MAX310X platform data structure */
+struct max310x_pdata {
+	/* Flags global to driver */
+	const u8		driver_flags:2;
+#define MAX310X_EXT_CLK		(0x00000001)	/* External clock enable */
+#define MAX310X_AUTOSLEEP	(0x00000002)	/* Enable AutoSleep mode */
+	/* Flags global to UART port */
+	const u8		uart_flags[MAX310X_MAX_UARTS];
+#define MAX310X_LOOPBACK	(0x00000001)	/* Loopback mode enable */
+#define MAX310X_ECHO_SUPRESS	(0x00000002)	/* Enable echo supress */
+#define MAX310X_AUTO_DIR_CTRL	(0x00000004)	/* Enable Auto direction
+						 * control (RS-485)
+						 */
+	/* Frequency (extrenal clock or crystal) */
+	const int		frequency;
+	/* GPIO base number (can be negative) */
+	const int		gpio_base;
+	/* Called during startup */
+	void (*init)(void);
+	/* Called before finish */
+	void (*exit)(void);
+	/* Suspend callback */
+	void (*suspend)(int do_suspend);
+};
+
+#endif

include/linux/serial_core.h

@@ -193,8 +193,8 @@
 /* SH-SCI */
 #define PORT_SCIFB	93
 
-/* MAX3107 */
-#define PORT_MAX3107	94
+/* MAX310X */
+#define PORT_MAX310X	94
 
 /* High Speed UART for Medfield */
 #define PORT_MFD	95