serial: New serial driver SCCNXP

This driver is a replacement for a SC26XX driver with a lot of
improvements and new features.
The main differences from the SC26XX driver:
- Removed dependency on MIPS. Driver can be used on any platform.
- Added support for SCC2681, SCC2691, SCC2692, SC28L91, SC28L92,
  SC28L202, SCC68681 and SCC68692 ICs.
- Using devm_-related functions.
- Improved error handling of serial port, improved FIFO handling.
- Ability to load multiple instances of drivers.

To avoid the possibility of regression, driver SC26XX left in the
system to confirm the stability of the driver on platforms where
it is being used.
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/Kconfig

@@ -1130,6 +1130,24 @@ config SERIAL_SC26XX_CONSOLE
 	help
 	  Support for Console on SC2681/SC2692 serial ports.
 
+config SERIAL_SCCNXP
+	bool "SCCNXP serial port support"
+	depends on !SERIAL_SC26XX
+	select SERIAL_CORE
+	default n
+	help
+	  This selects support for an advanced UART from NXP (Philips).
+	  Supported ICs are SCC2681, SCC2691, SCC2692, SC28L91, SC28L92,
+	  SC28L202, SCC68681 and SCC68692.
+	  Positioned as a replacement for the driver SC26XX.
+
+config SERIAL_SCCNXP_CONSOLE
+	bool "Console on SCCNXP serial port"
+	depends on SERIAL_SCCNXP
+	select SERIAL_CORE_CONSOLE
+	help
+	  Support for console on SCCNXP serial ports.
+
 config SERIAL_BFIN_SPORT
 	tristate "Blackfin SPORT emulate UART"
 	depends on BLACKFIN

drivers/tty/serial/Makefile

@@ -48,6 +48,7 @@ obj-$(CONFIG_SERIAL_MPSC) += mpsc.o
 obj-$(CONFIG_SERIAL_SB1250_DUART) += sb1250-duart.o
 obj-$(CONFIG_ETRAX_SERIAL) += crisv10.o
 obj-$(CONFIG_SERIAL_SC26XX) += sc26xx.o
+obj-$(CONFIG_SERIAL_SCCNXP) += sccnxp.o
 obj-$(CONFIG_SERIAL_JSM) += jsm/
 obj-$(CONFIG_SERIAL_TXX9) += serial_txx9.o
 obj-$(CONFIG_SERIAL_VR41XX) += vr41xx_siu.o

include/linux/platform_data/sccnxp.h

+/*
+ *  NXP (Philips) SCC+++(SCN+++) serial driver
+ *
+ *  Copyright (C) 2012 Alexander Shiyan <shc_work@mail.ru>
+ *
+ *  Based on sc26xx.c, by Thomas Bogendörfer (tsbogend@alpha.franken.de)
+ *
+ *  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 __SCCNXP_H
+#define __SCCNXP_H
+
+#define SCCNXP_MAX_UARTS	2
+
+/* Output lines */
+#define LINE_OP0		1
+#define LINE_OP1		2
+#define LINE_OP2		3
+#define LINE_OP3		4
+#define LINE_OP4		5
+#define LINE_OP5		6
+#define LINE_OP6		7
+#define LINE_OP7		8
+
+/* Input lines */
+#define LINE_IP0		9
+#define LINE_IP1		10
+#define LINE_IP2		11
+#define LINE_IP3		12
+#define LINE_IP4		13
+#define LINE_IP5		14
+#define LINE_IP6		15
+
+/* Signals */
+#define DTR_OP			0	/* DTR */
+#define RTS_OP			4	/* RTS */
+#define DSR_IP			8	/* DSR */
+#define CTS_IP			12	/* CTS */
+#define DCD_IP			16	/* DCD */
+#define RNG_IP			20	/* RNG */
+
+#define DIR_OP			24	/* Special signal for control RS-485.
+					 * Goes high when transmit,
+					 * then goes low.
+					 */
+
+/* Routing control signal 'sig' to line 'line' */
+#define MCTRL_SIG(sig, line)	((line) << (sig))
+
+/*
+ * Example board initialization data:
+ *
+ * static struct resource sc2892_resources[] = {
+ *	DEFINE_RES_MEM(UART_PHYS_START, 0x10),
+ *	DEFINE_RES_IRQ(IRQ_EXT2),
+ * };
+ *
+ * static struct sccnxp_pdata sc2892_info = {
+ *	.frequency	= 3686400,
+ *	.mctrl_cfg[0]	= MCTRL_SIG(DIR_OP, LINE_OP0),
+ *	.mctrl_cfg[1]	= MCTRL_SIG(DIR_OP, LINE_OP1),
+ * };
+ *
+ * static struct platform_device sc2892 = {
+ *	.name		= "sc2892",
+ *	.id		= -1,
+ *	.resource	= sc2892_resources,
+ *	.num_resources	= ARRAY_SIZE(sc2892_resources),
+ *	.dev = {
+ *		.platform_data	= &sc2892_info,
+ *	},
+ * };
+ */
+
+/* SCCNXP platform data structure */
+struct sccnxp_pdata {
+	/* Frequency (extrenal clock or crystal) */
+	int			frequency;
+	/* Shift for A0 line */
+	const u8		reg_shift;
+	/* Modem control lines configuration */
+	const u32		mctrl_cfg[SCCNXP_MAX_UARTS];
+	/* Called during startup */
+	void (*init)(void);
+	/* Called before finish */
+	void (*exit)(void);
+};
+
+#endif