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

drivers/tty/serial/sccnxp.c

+/*
+ *  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.
+ */
+
+#if defined(CONFIG_SERIAL_SCCNXP_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/serial_core.h>
+#include <linux/serial.h>
+#include <linux/io.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/console.h>
+#include <linux/platform_device.h>
+#include <linux/platform_data/sccnxp.h>
+
+#define SCCNXP_NAME			"uart-sccnxp"
+#define SCCNXP_MAJOR			204
+#define SCCNXP_MINOR			205
+
+#define SCCNXP_MR_REG			(0x00)
+#	define MR0_BAUD_NORMAL		(0 << 0)
+#	define MR0_BAUD_EXT1		(1 << 0)
+#	define MR0_BAUD_EXT2		(5 << 0)
+#	define MR0_FIFO			(1 << 3)
+#	define MR0_TXLVL		(1 << 4)
+#	define MR1_BITS_5		(0 << 0)
+#	define MR1_BITS_6		(1 << 0)
+#	define MR1_BITS_7		(2 << 0)
+#	define MR1_BITS_8		(3 << 0)
+#	define MR1_PAR_EVN		(0 << 2)
+#	define MR1_PAR_ODD		(1 << 2)
+#	define MR1_PAR_NO		(4 << 2)
+#	define MR2_STOP1		(7 << 0)
+#	define MR2_STOP2		(0xf << 0)
+#define SCCNXP_SR_REG			(0x01)
+#define SCCNXP_CSR_REG			SCCNXP_SR_REG
+#	define SR_RXRDY			(1 << 0)
+#	define SR_FULL			(1 << 1)
+#	define SR_TXRDY			(1 << 2)
+#	define SR_TXEMT			(1 << 3)
+#	define SR_OVR			(1 << 4)
+#	define SR_PE			(1 << 5)
+#	define SR_FE			(1 << 6)
+#	define SR_BRK			(1 << 7)
+#define SCCNXP_CR_REG			(0x02)
+#	define CR_RX_ENABLE		(1 << 0)
+#	define CR_RX_DISABLE		(1 << 1)
+#	define CR_TX_ENABLE		(1 << 2)
+#	define CR_TX_DISABLE		(1 << 3)
+#	define CR_CMD_MRPTR1		(0x01 << 4)
+#	define CR_CMD_RX_RESET		(0x02 << 4)
+#	define CR_CMD_TX_RESET		(0x03 << 4)
+#	define CR_CMD_STATUS_RESET	(0x04 << 4)
+#	define CR_CMD_BREAK_RESET	(0x05 << 4)
+#	define CR_CMD_START_BREAK	(0x06 << 4)
+#	define CR_CMD_STOP_BREAK	(0x07 << 4)
+#	define CR_CMD_MRPTR0		(0x0b << 4)
+#define SCCNXP_RHR_REG			(0x03)
+#define SCCNXP_THR_REG			SCCNXP_RHR_REG
+#define SCCNXP_IPCR_REG			(0x04)
+#define SCCNXP_ACR_REG			SCCNXP_IPCR_REG
+#	define ACR_BAUD0		(0 << 7)
+#	define ACR_BAUD1		(1 << 7)
+#	define ACR_TIMER_MODE		(6 << 4)
+#define SCCNXP_ISR_REG			(0x05)
+#define SCCNXP_IMR_REG			SCCNXP_ISR_REG
+#	define IMR_TXRDY		(1 << 0)
+#	define IMR_RXRDY		(1 << 1)
+#	define ISR_TXRDY(x)		(1 << ((x * 4) + 0))
+#	define ISR_RXRDY(x)		(1 << ((x * 4) + 1))
+#define SCCNXP_IPR_REG			(0x0d)
+#define SCCNXP_OPCR_REG			SCCNXP_IPR_REG
+#define SCCNXP_SOP_REG			(0x0e)
+#define SCCNXP_ROP_REG			(0x0f)
+
+/* Route helpers */
+#define MCTRL_MASK(sig)			(0xf << (sig))
+#define MCTRL_IBIT(cfg, sig)		((((cfg) >> (sig)) & 0xf) - LINE_IP0)
+#define MCTRL_OBIT(cfg, sig)		((((cfg) >> (sig)) & 0xf) - LINE_OP0)
+
+/* Supported chip types */
+enum {
+	SCCNXP_TYPE_SC2681	= 2681,
+	SCCNXP_TYPE_SC2691	= 2691,
+	SCCNXP_TYPE_SC2692	= 2692,
+	SCCNXP_TYPE_SC2891	= 2891,
+	SCCNXP_TYPE_SC2892	= 2892,
+	SCCNXP_TYPE_SC28202	= 28202,
+	SCCNXP_TYPE_SC68681	= 68681,
+	SCCNXP_TYPE_SC68692	= 68692,
+};
+
+struct sccnxp_port {
+	struct uart_driver	uart;
+	struct uart_port	port[SCCNXP_MAX_UARTS];
+
+	const char		*name;
+	int			irq;
+
+	u8			imr;
+	u8			addr_mask;
+	int			freq_std;
+
+	int			flags;
+#define SCCNXP_HAVE_IO		0x00000001
+#define SCCNXP_HAVE_MR0		0x00000002
+
+#ifdef CONFIG_SERIAL_SCCNXP_CONSOLE
+	struct console		console;
+#endif
+
+	struct mutex		sccnxp_mutex;
+
+	struct sccnxp_pdata	pdata;
+};
+
+static inline u8 sccnxp_raw_read(void __iomem *base, u8 reg, u8 shift)
+{
+	return readb(base + (reg << shift));
+}
+
+static inline void sccnxp_raw_write(void __iomem *base, u8 reg, u8 shift, u8 v)
+{
+	writeb(v, base + (reg << shift));
+}
+
+static inline u8 sccnxp_read(struct uart_port *port, u8 reg)
+{
+	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+
+	return sccnxp_raw_read(port->membase, reg & s->addr_mask,
+			       port->regshift);
+}
+
+static inline void sccnxp_write(struct uart_port *port, u8 reg, u8 v)
+{
+	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+
+	sccnxp_raw_write(port->membase, reg & s->addr_mask, port->regshift, v);
+}
+
+static inline u8 sccnxp_port_read(struct uart_port *port, u8 reg)
+{
+	return sccnxp_read(port, (port->line << 3) + reg);
+}
+
+static inline void sccnxp_port_write(struct uart_port *port, u8 reg, u8 v)
+{
+	sccnxp_write(port, (port->line << 3) + reg, v);
+}
+
+static int sccnxp_update_best_err(int a, int b, int *besterr)
+{
+	int err = abs(a - b);
+
+	if ((*besterr < 0) || (*besterr > err)) {
+		*besterr = err;
+		return 0;
+	}
+
+	return 1;
+}
+
+struct baud_table {
+	u8	csr;
+	u8	acr;
+	u8	mr0;
+	int	baud;
+};
+
+const struct baud_table baud_std[] = {
+	{ 0,	ACR_BAUD0,	MR0_BAUD_NORMAL,	50, },
+	{ 0,	ACR_BAUD1,	MR0_BAUD_NORMAL,	75, },
+	{ 1,	ACR_BAUD0,	MR0_BAUD_NORMAL,	110, },
+	{ 2,	ACR_BAUD0,	MR0_BAUD_NORMAL,	134, },
+	{ 3,	ACR_BAUD1,	MR0_BAUD_NORMAL,	150, },
+	{ 3,	ACR_BAUD0,	MR0_BAUD_NORMAL,	200, },
+	{ 4,	ACR_BAUD0,	MR0_BAUD_NORMAL,	300, },
+	{ 0,	ACR_BAUD1,	MR0_BAUD_EXT1,		450, },
+	{ 1,	ACR_BAUD0,	MR0_BAUD_EXT2,		880, },
+	{ 3,	ACR_BAUD1,	MR0_BAUD_EXT1,		900, },
+	{ 5,	ACR_BAUD0,	MR0_BAUD_NORMAL,	600, },
+	{ 7,	ACR_BAUD0,	MR0_BAUD_NORMAL,	1050, },
+	{ 2,	ACR_BAUD0,	MR0_BAUD_EXT2,		1076, },
+	{ 6,	ACR_BAUD0,	MR0_BAUD_NORMAL,	1200, },
+	{ 10,	ACR_BAUD1,	MR0_BAUD_NORMAL,	1800, },
+	{ 7,	ACR_BAUD1,	MR0_BAUD_NORMAL,	2000, },
+	{ 8,	ACR_BAUD0,	MR0_BAUD_NORMAL,	2400, },
+	{ 5,	ACR_BAUD1,	MR0_BAUD_EXT1,		3600, },
+	{ 9,	ACR_BAUD0,	MR0_BAUD_NORMAL,	4800, },
+	{ 10,	ACR_BAUD0,	MR0_BAUD_NORMAL,	7200, },
+	{ 11,	ACR_BAUD0,	MR0_BAUD_NORMAL,	9600, },
+	{ 8,	ACR_BAUD0,	MR0_BAUD_EXT1,		14400, },
+	{ 12,	ACR_BAUD1,	MR0_BAUD_NORMAL,	19200, },
+	{ 9,	ACR_BAUD0,	MR0_BAUD_EXT1,		28800, },
+	{ 12,	ACR_BAUD0,	MR0_BAUD_NORMAL,	38400, },
+	{ 11,	ACR_BAUD0,	MR0_BAUD_EXT1,		57600, },
+	{ 12,	ACR_BAUD1,	MR0_BAUD_EXT1,		115200, },
+	{ 12,	ACR_BAUD0,	MR0_BAUD_EXT1,		230400, },
+	{ 0, 0, 0, 0 }
+};
+
+static void sccnxp_set_baud(struct uart_port *port, int baud)
+{
+	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+	int div_std, tmp_baud, bestbaud = baud, besterr = -1;
+	u8 i, acr = 0, csr = 0, mr0 = 0;
+
+	/* Find best baud from table */
+	for (i = 0; baud_std[i].baud && besterr; i++) {
+		if (baud_std[i].mr0 && !(s->flags & SCCNXP_HAVE_MR0))
+			continue;
+		div_std = DIV_ROUND_CLOSEST(s->freq_std, baud_std[i].baud);
+		tmp_baud = DIV_ROUND_CLOSEST(port->uartclk, div_std);
+		if (!sccnxp_update_best_err(baud, tmp_baud, &besterr)) {
+			acr = baud_std[i].acr;
+			csr = baud_std[i].csr;
+			mr0 = baud_std[i].mr0;
+			bestbaud = tmp_baud;
+		}
+	}
+
+	if (s->flags & SCCNXP_HAVE_MR0) {
+		/* Enable FIFO, set half level for TX */
+		mr0 |= MR0_FIFO | MR0_TXLVL;
+		/* Update MR0 */
+		sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_MRPTR0);
+		sccnxp_port_write(port, SCCNXP_MR_REG, mr0);
+	}
+
+	sccnxp_port_write(port, SCCNXP_ACR_REG, acr | ACR_TIMER_MODE);
+	sccnxp_port_write(port, SCCNXP_CSR_REG, (csr << 4) | csr);
+
+	dev_dbg(port->dev, "Baudrate desired: %i, calculated: %i\n",
+		baud, bestbaud);
+}
+
+static void sccnxp_enable_irq(struct uart_port *port, int mask)
+{
+	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+
+	s->imr |= mask << (port->line * 4);
+	sccnxp_write(port, SCCNXP_IMR_REG, s->imr);
+}
+
+static void sccnxp_disable_irq(struct uart_port *port, int mask)
+{
+	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+
+	s->imr &= ~(mask << (port->line * 4));
+	sccnxp_write(port, SCCNXP_IMR_REG, s->imr);
+}
+
+static void sccnxp_set_bit(struct uart_port *port, int sig, int state)
+{
+	u8 bitmask;
+	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+
+	if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(sig)) {
+		bitmask = 1 << MCTRL_OBIT(s->pdata.mctrl_cfg[port->line], sig);
+		if (state)
+			sccnxp_write(port, SCCNXP_SOP_REG, bitmask);
+		else
+			sccnxp_write(port, SCCNXP_ROP_REG, bitmask);
+	}
+}
+
+static void sccnxp_handle_rx(struct uart_port *port)
+{
+	u8 sr;
+	unsigned int ch, flag;
+	struct tty_struct *tty = tty_port_tty_get(&port->state->port);
+
+	if (!tty)
+		return;
+
+	for (;;) {
+		sr = sccnxp_port_read(port, SCCNXP_SR_REG);
+		if (!(sr & SR_RXRDY))
+			break;
+		sr &= SR_PE | SR_FE | SR_OVR | SR_BRK;
+
+		ch = sccnxp_port_read(port, SCCNXP_RHR_REG);
+
+		port->icount.rx++;
+		flag = TTY_NORMAL;
+
+		if (unlikely(sr)) {
+			if (sr & SR_BRK) {
+				port->icount.brk++;
+				if (uart_handle_break(port))
+					continue;
+			} else if (sr & SR_PE)
+				port->icount.parity++;
+			else if (sr & SR_FE)
+				port->icount.frame++;
+			else if (sr & SR_OVR)
+				port->icount.overrun++;
+
+			sr &= port->read_status_mask;
+			if (sr & SR_BRK)
+				flag = TTY_BREAK;
+			else if (sr & SR_PE)
+				flag = TTY_PARITY;
+			else if (sr & SR_FE)
+				flag = TTY_FRAME;
+			else if (sr & SR_OVR)
+				flag = TTY_OVERRUN;
+		}
+
+		if (uart_handle_sysrq_char(port, ch))
+			continue;
+
+		if (sr & port->ignore_status_mask)
+			continue;
+
+		uart_insert_char(port, sr, SR_OVR, ch, flag);
+	}
+
+	tty_flip_buffer_push(tty);
+
+	tty_kref_put(tty);
+}
+
+static void sccnxp_handle_tx(struct uart_port *port)
+{
+	u8 sr;
+	struct circ_buf *xmit = &port->state->xmit;
+	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+
+	if (unlikely(port->x_char)) {
+		sccnxp_port_write(port, SCCNXP_THR_REG, port->x_char);
+		port->icount.tx++;
+		port->x_char = 0;
+		return;
+	}
+
+	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
+		/* Disable TX if FIFO is empty */
+		if (sccnxp_port_read(port, SCCNXP_SR_REG) & SR_TXEMT) {
+			sccnxp_disable_irq(port, IMR_TXRDY);
+
+			/* Set direction to input */
+			if (s->flags & SCCNXP_HAVE_IO)
+				sccnxp_set_bit(port, DIR_OP, 0);
+		}
+		return;
+	}
+
+	while (!uart_circ_empty(xmit)) {
+		sr = sccnxp_port_read(port, SCCNXP_SR_REG);
+		if (!(sr & SR_TXRDY))
+			break;
+
+		sccnxp_port_write(port, SCCNXP_THR_REG, xmit->buf[xmit->tail]);
+		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+		port->icount.tx++;
+	}
+
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+		uart_write_wakeup(port);
+}
+
+static irqreturn_t sccnxp_ist(int irq, void *dev_id)
+{
+	int i;
+	u8 isr;
+	struct sccnxp_port *s = (struct sccnxp_port *)dev_id;
+
+	mutex_lock(&s->sccnxp_mutex);
+
+	for (;;) {
+		isr = sccnxp_read(&s->port[0], SCCNXP_ISR_REG);
+		isr &= s->imr;
+		if (!isr)
+			break;
+
+		dev_dbg(s->port[0].dev, "IRQ status: 0x%02x\n", isr);
+
+		for (i = 0; i < s->uart.nr; i++) {
+			if (isr & ISR_RXRDY(i))
+				sccnxp_handle_rx(&s->port[i]);
+			if (isr & ISR_TXRDY(i))
+				sccnxp_handle_tx(&s->port[i]);
+		}
+	}
+
+	mutex_unlock(&s->sccnxp_mutex);
+
+	return IRQ_HANDLED;
+}
+
+static void sccnxp_start_tx(struct uart_port *port)
+{
+	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+
+	mutex_lock(&s->sccnxp_mutex);
+
+	/* Set direction to output */
+	if (s->flags & SCCNXP_HAVE_IO)
+		sccnxp_set_bit(port, DIR_OP, 1);
+
+	sccnxp_enable_irq(port, IMR_TXRDY);
+
+	mutex_unlock(&s->sccnxp_mutex);
+}
+
+static void sccnxp_stop_tx(struct uart_port *port)
+{
+	/* Do nothing */
+}
+
+static void sccnxp_stop_rx(struct uart_port *port)
+{
+	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+
+	mutex_lock(&s->sccnxp_mutex);
+	sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_DISABLE);
+	mutex_unlock(&s->sccnxp_mutex);
+}
+
+static unsigned int sccnxp_tx_empty(struct uart_port *port)
+{
+	u8 val;
+	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+
+	mutex_lock(&s->sccnxp_mutex);
+	val = sccnxp_port_read(port, SCCNXP_SR_REG);
+	mutex_unlock(&s->sccnxp_mutex);
+
+	return (val & SR_TXEMT) ? TIOCSER_TEMT : 0;
+}
+
+static void sccnxp_enable_ms(struct uart_port *port)
+{
+	/* Do nothing */
+}
+
+static void sccnxp_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+
+	if (!(s->flags & SCCNXP_HAVE_IO))
+		return;
+
+	mutex_lock(&s->sccnxp_mutex);
+
+	sccnxp_set_bit(port, DTR_OP, mctrl & TIOCM_DTR);
+	sccnxp_set_bit(port, RTS_OP, mctrl & TIOCM_RTS);
+
+	mutex_unlock(&s->sccnxp_mutex);
+}
+
+static unsigned int sccnxp_get_mctrl(struct uart_port *port)
+{
+	u8 bitmask, ipr;
+	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+	unsigned int mctrl = TIOCM_DSR | TIOCM_CTS | TIOCM_CAR;
+
+	if (!(s->flags & SCCNXP_HAVE_IO))
+		return mctrl;
+
+	mutex_lock(&s->sccnxp_mutex);
+
+	ipr = ~sccnxp_read(port, SCCNXP_IPCR_REG);
+
+	if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(DSR_IP)) {
+		bitmask = 1 << MCTRL_IBIT(s->pdata.mctrl_cfg[port->line],
+					  DSR_IP);
+		mctrl &= ~TIOCM_DSR;
+		mctrl |= (ipr & bitmask) ? TIOCM_DSR : 0;
+	}
+	if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(CTS_IP)) {
+		bitmask = 1 << MCTRL_IBIT(s->pdata.mctrl_cfg[port->line],
+					  CTS_IP);
+		mctrl &= ~TIOCM_CTS;
+		mctrl |= (ipr & bitmask) ? TIOCM_CTS : 0;
+	}
+	if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(DCD_IP)) {
+		bitmask = 1 << MCTRL_IBIT(s->pdata.mctrl_cfg[port->line],
+					  DCD_IP);
+		mctrl &= ~TIOCM_CAR;
+		mctrl |= (ipr & bitmask) ? TIOCM_CAR : 0;
+	}
+	if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(RNG_IP)) {
+		bitmask = 1 << MCTRL_IBIT(s->pdata.mctrl_cfg[port->line],
+					  RNG_IP);
+		mctrl &= ~TIOCM_RNG;
+		mctrl |= (ipr & bitmask) ? TIOCM_RNG : 0;
+	}
+
+	mutex_unlock(&s->sccnxp_mutex);
+
+	return mctrl;
+}
+
+static void sccnxp_break_ctl(struct uart_port *port, int break_state)
+{
+	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+
+	mutex_lock(&s->sccnxp_mutex);
+	sccnxp_port_write(port, SCCNXP_CR_REG, break_state ?
+			  CR_CMD_START_BREAK : CR_CMD_STOP_BREAK);
+	mutex_unlock(&s->sccnxp_mutex);
+}
+
+static void sccnxp_set_termios(struct uart_port *port,
+			       struct ktermios *termios, struct ktermios *old)
+{
+	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+	u8 mr1, mr2;
+	int baud;
+
+	mutex_lock(&s->sccnxp_mutex);
+
+	/* Mask termios capabilities we don't support */
+	termios->c_cflag &= ~CMSPAR;
+	termios->c_iflag &= ~(IXON | IXOFF | IXANY);
+
+	/* Disable RX & TX, reset break condition, status and FIFOs */
+	sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_RX_RESET |
+					       CR_RX_DISABLE | CR_TX_DISABLE);
+	sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_TX_RESET);
+	sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_STATUS_RESET);
+	sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_BREAK_RESET);
+
+	/* Word size */
+	switch (termios->c_cflag & CSIZE) {
+	case CS5:
+		mr1 = MR1_BITS_5;
+		break;
+	case CS6:
+		mr1 = MR1_BITS_6;
+		break;
+	case CS7:
+		mr1 = MR1_BITS_7;
+		break;
+	default:
+	case CS8:
+		mr1 = MR1_BITS_8;
+		break;
+	}
+
+	/* Parity */
+	if (termios->c_cflag & PARENB) {
+		if (termios->c_cflag & PARODD)
+			mr1 |= MR1_PAR_ODD;
+	} else
+		mr1 |= MR1_PAR_NO;
+
+	/* Stop bits */
+	mr2 = (termios->c_cflag & CSTOPB) ? MR2_STOP2 : MR2_STOP1;
+
+	/* Update desired format */
+	sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_MRPTR1);
+	sccnxp_port_write(port, SCCNXP_MR_REG, mr1);
+	sccnxp_port_write(port, SCCNXP_MR_REG, mr2);
+
+	/* Set read status mask */
+	port->read_status_mask = SR_OVR;
+	if (termios->c_iflag & INPCK)
+		port->read_status_mask |= SR_PE | SR_FE;
+	if (termios->c_iflag & (BRKINT | PARMRK))
+		port->read_status_mask |= SR_BRK;
+
+	/* Set status ignore mask */
+	port->ignore_status_mask = 0;
+	if (termios->c_iflag & IGNBRK)
+		port->ignore_status_mask |= SR_BRK;
+	if (!(termios->c_cflag & CREAD))
+		port->ignore_status_mask |= SR_PE | SR_OVR | SR_FE | SR_BRK;
+
+	/* Setup baudrate */
+	baud = uart_get_baud_rate(port, termios, old, 50,
+				  (s->flags & SCCNXP_HAVE_MR0) ?
+				  230400 : 38400);
+	sccnxp_set_baud(port, baud);
+
+	/* Update timeout according to new baud rate */
+	uart_update_timeout(port, termios->c_cflag, baud);
+
+	/* Enable RX & TX */
+	sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_ENABLE | CR_TX_ENABLE);
+
+	mutex_unlock(&s->sccnxp_mutex);
+}
+
+static int sccnxp_startup(struct uart_port *port)
+{
+	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+
+	mutex_lock(&s->sccnxp_mutex);
+
+	if (s->flags & SCCNXP_HAVE_IO) {
+		/* Outputs are controlled manually */
+		sccnxp_write(port, SCCNXP_OPCR_REG, 0);
+	}
+
+	/* Reset break condition, status and FIFOs */
+	sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_RX_RESET);
+	sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_TX_RESET);
+	sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_STATUS_RESET);
+	sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_BREAK_RESET);
+
+	/* Enable RX & TX */
+	sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_ENABLE | CR_TX_ENABLE);
+
+	/* Enable RX interrupt */
+	sccnxp_enable_irq(port, IMR_RXRDY);
+
+	mutex_unlock(&s->sccnxp_mutex);
+
+	return 0;
+}
+
+static void sccnxp_shutdown(struct uart_port *port)
+{
+	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+
+	mutex_lock(&s->sccnxp_mutex);
+
+	/* Disable interrupts */
+	sccnxp_disable_irq(port, IMR_TXRDY | IMR_RXRDY);
+
+	/* Disable TX & RX */
+	sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_DISABLE | CR_TX_DISABLE);
+
+	/* Leave direction to input */
+	if (s->flags & SCCNXP_HAVE_IO)
+		sccnxp_set_bit(port, DIR_OP, 0);
+
+	mutex_unlock(&s->sccnxp_mutex);
+}
+
+static const char *sccnxp_type(struct uart_port *port)
+{
+	struct sccnxp_port *s = dev_get_drvdata(port->dev);
+
+	return (port->type == PORT_SC26XX) ? s->name : NULL;
+}
+
+static void sccnxp_release_port(struct uart_port *port)
+{
+	/* Do nothing */
+}
+
+static int sccnxp_request_port(struct uart_port *port)
+{
+	/* Do nothing */
+	return 0;
+}
+
+static void sccnxp_config_port(struct uart_port *port, int flags)
+{
+	if (flags & UART_CONFIG_TYPE)
+		port->type = PORT_SC26XX;
+}
+
+static int sccnxp_verify_port(struct uart_port *port, struct serial_struct *s)
+{
+	if ((s->type == PORT_UNKNOWN) || (s->type == PORT_SC26XX))
+		return 0;
+	if (s->irq == port->irq)
+		return 0;
+
+	return -EINVAL;
+}
+
+static const struct uart_ops sccnxp_ops = {
+	.tx_empty	= sccnxp_tx_empty,
+	.set_mctrl	= sccnxp_set_mctrl,
+	.get_mctrl	= sccnxp_get_mctrl,
+	.stop_tx	= sccnxp_stop_tx,
+	.start_tx	= sccnxp_start_tx,
+	.stop_rx	= sccnxp_stop_rx,
+	.enable_ms	= sccnxp_enable_ms,
+	.break_ctl	= sccnxp_break_ctl,
+	.startup	= sccnxp_startup,
+	.shutdown	= sccnxp_shutdown,
+	.set_termios	= sccnxp_set_termios,
+	.type		= sccnxp_type,
+	.release_port	= sccnxp_release_port,
+	.request_port	= sccnxp_request_port,
+	.config_port	= sccnxp_config_port,
+	.verify_port	= sccnxp_verify_port,
+};
+
+#ifdef CONFIG_SERIAL_SCCNXP_CONSOLE
+static void sccnxp_console_putchar(struct uart_port *port, int c)
+{
+	int tryes = 100000;
+
+	while (tryes--) {
+		if (sccnxp_port_read(port, SCCNXP_SR_REG) & SR_TXRDY) {
+			sccnxp_port_write(port, SCCNXP_THR_REG, c);
+			break;
+		}
+		barrier();
+	}
+}
+
+static void sccnxp_console_write(struct console *co, const char *c, unsigned n)
+{
+	struct sccnxp_port *s = (struct sccnxp_port *)co->data;
+	struct uart_port *port = &s->port[co->index];
+
+	mutex_lock(&s->sccnxp_mutex);
+	uart_console_write(port, c, n, sccnxp_console_putchar);
+	mutex_unlock(&s->sccnxp_mutex);
+}
+
+static int sccnxp_console_setup(struct console *co, char *options)
+{
+	struct sccnxp_port *s = (struct sccnxp_port *)co->data;
+	struct uart_port *port = &s->port[(co->index > 0) ? co->index : 0];
+	int baud = 9600, bits = 8, parity = 'n', flow = 'n';
+
+	if (options)
+		uart_parse_options(options, &baud, &parity, &bits, &flow);
+
+	return uart_set_options(port, co, baud, parity, bits, flow);
+}
+#endif
+
+static int __devinit sccnxp_probe(struct platform_device *pdev)
+{
+	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	int chiptype = pdev->id_entry->driver_data;
+	struct sccnxp_pdata *pdata = dev_get_platdata(&pdev->dev);
+	int i, ret, fifosize, freq_min, freq_max;
+	struct sccnxp_port *s;
+	void __iomem *membase;
+
+	if (!res) {
+		dev_err(&pdev->dev, "Missing memory resource data\n");
+		return -EADDRNOTAVAIL;
+	}
+
+	dev_set_name(&pdev->dev, SCCNXP_NAME);
+
+	s = devm_kzalloc(&pdev->dev, sizeof(struct sccnxp_port), GFP_KERNEL);
+	if (!s) {
+		dev_err(&pdev->dev, "Error allocating port structure\n");
+		return -ENOMEM;
+	}
+	platform_set_drvdata(pdev, s);
+
+	mutex_init(&s->sccnxp_mutex);
+
+	/* Individual chip settings */
+	switch (chiptype) {
+	case SCCNXP_TYPE_SC2681:
+		s->name		= "SC2681";
+		s->uart.nr	= 2;
+		s->freq_std	= 3686400;
+		s->addr_mask	= 0x0f;
+		s->flags	= SCCNXP_HAVE_IO;
+		fifosize	= 3;
+		freq_min	= 1000000;
+		freq_max	= 4000000;
+		break;
+	case SCCNXP_TYPE_SC2691:
+		s->name		= "SC2691";
+		s->uart.nr	= 1;
+		s->freq_std	= 3686400;
+		s->addr_mask	= 0x07;
+		s->flags	= 0;
+		fifosize	= 3;
+		freq_min	= 1000000;
+		freq_max	= 4000000;
+		break;
+	case SCCNXP_TYPE_SC2692:
+		s->name		= "SC2692";
+		s->uart.nr	= 2;
+		s->freq_std	= 3686400;
+		s->addr_mask	= 0x0f;
+		s->flags	= SCCNXP_HAVE_IO;
+		fifosize	= 3;
+		freq_min	= 1000000;
+		freq_max	= 4000000;
+		break;
+	case SCCNXP_TYPE_SC2891:
+		s->name		= "SC2891";
+		s->uart.nr	= 1;
+		s->freq_std	= 3686400;
+		s->addr_mask	= 0x0f;
+		s->flags	= SCCNXP_HAVE_IO | SCCNXP_HAVE_MR0;
+		fifosize	= 16;
+		freq_min	= 100000;
+		freq_max	= 8000000;
+		break;
+	case SCCNXP_TYPE_SC2892:
+		s->name		= "SC2892";
+		s->uart.nr	= 2;
+		s->freq_std	= 3686400;
+		s->addr_mask	= 0x0f;
+		s->flags	= SCCNXP_HAVE_IO | SCCNXP_HAVE_MR0;
+		fifosize	= 16;
+		freq_min	= 100000;
+		freq_max	= 8000000;
+		break;
+	case SCCNXP_TYPE_SC28202:
+		s->name		= "SC28202";
+		s->uart.nr	= 2;
+		s->freq_std	= 14745600;
+		s->addr_mask	= 0x7f;
+		s->flags	= SCCNXP_HAVE_IO | SCCNXP_HAVE_MR0;
+		fifosize	= 256;
+		freq_min	= 1000000;
+		freq_max	= 50000000;
+		break;
+	case SCCNXP_TYPE_SC68681:
+		s->name		= "SC68681";
+		s->uart.nr	= 2;
+		s->freq_std	= 3686400;
+		s->addr_mask	= 0x0f;
+		s->flags	= SCCNXP_HAVE_IO;
+		fifosize	= 3;
+		freq_min	= 1000000;
+		freq_max	= 4000000;
+		break;
+	case SCCNXP_TYPE_SC68692:
+		s->name		= "SC68692";
+		s->uart.nr	= 2;
+		s->freq_std	= 3686400;
+		s->addr_mask	= 0x0f;
+		s->flags	= SCCNXP_HAVE_IO;
+		fifosize	= 3;
+		freq_min	= 1000000;
+		freq_max	= 4000000;
+		break;
+	default:
+		dev_err(&pdev->dev, "Unsupported chip type %i\n", chiptype);
+		ret = -ENOTSUPP;
+		goto err_out;
+	}
+
+	if (!pdata) {
+		dev_warn(&pdev->dev,
+			 "No platform data supplied, using defaults\n");
+		s->pdata.frequency = s->freq_std;
+	} else
+		memcpy(&s->pdata, pdata, sizeof(struct sccnxp_pdata));
+
+	s->irq = platform_get_irq(pdev, 0);
+	if (s->irq <= 0) {
+		dev_err(&pdev->dev, "Missing irq resource data\n");
+		ret = -ENXIO;
+		goto err_out;
+	}
+
+	/* Check input frequency */
+	if ((s->pdata.frequency < freq_min) ||
+	    (s->pdata.frequency > freq_max)) {
+		dev_err(&pdev->dev, "Frequency out of bounds\n");
+		ret = -EINVAL;
+		goto err_out;
+	}
+
+	membase = devm_request_and_ioremap(&pdev->dev, res);
+	if (!membase) {
+		dev_err(&pdev->dev, "Failed to ioremap\n");
+		ret = -EIO;
+		goto err_out;
+	}
+
+	s->uart.owner		= THIS_MODULE;
+	s->uart.dev_name	= "ttySC";
+	s->uart.major		= SCCNXP_MAJOR;
+	s->uart.minor		= SCCNXP_MINOR;
+#ifdef CONFIG_SERIAL_SCCNXP_CONSOLE
+	s->uart.cons		= &s->console;
+	s->uart.cons->device	= uart_console_device;
+	s->uart.cons->write	= sccnxp_console_write;
+	s->uart.cons->setup	= sccnxp_console_setup;
+	s->uart.cons->flags	= CON_PRINTBUFFER;
+	s->uart.cons->index	= -1;
+	s->uart.cons->data	= s;
+	strcpy(s->uart.cons->name, "ttySC");
+#endif
+	ret = uart_register_driver(&s->uart);
+	if (ret) {
+		dev_err(&pdev->dev, "Registering UART driver failed\n");
+		goto err_out;
+	}
+
+	for (i = 0; i < s->uart.nr; i++) {
+		s->port[i].line		= i;
+		s->port[i].dev		= &pdev->dev;
+		s->port[i].irq		= s->irq;
+		s->port[i].type		= PORT_SC26XX;
+		s->port[i].fifosize	= fifosize;
+		s->port[i].flags	= UPF_SKIP_TEST | UPF_FIXED_TYPE;
+		s->port[i].iotype	= UPIO_MEM;
+		s->port[i].mapbase	= res->start;
+		s->port[i].membase	= membase;
+		s->port[i].regshift	= s->pdata.reg_shift;
+		s->port[i].uartclk	= s->pdata.frequency;
+		s->port[i].ops		= &sccnxp_ops;
+		uart_add_one_port(&s->uart, &s->port[i]);
+		/* Set direction to input */
+		if (s->flags & SCCNXP_HAVE_IO)
+			sccnxp_set_bit(&s->port[i], DIR_OP, 0);
+	}
+
+	/* Disable interrupts */
+	s->imr = 0;
+	sccnxp_write(&s->port[0], SCCNXP_IMR_REG, 0);
+
+	/* Board specific configure */
+	if (s->pdata.init)
+		s->pdata.init();
+
+	ret = devm_request_threaded_irq(&pdev->dev, s->irq, NULL, sccnxp_ist,
+					IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+					dev_name(&pdev->dev), s);
+	if (!ret)
+		return 0;
+
+	dev_err(&pdev->dev, "Unable to reguest IRQ %i\n", s->irq);
+
+err_out:
+	platform_set_drvdata(pdev, NULL);
+
+	return ret;
+}
+
+static int __devexit sccnxp_remove(struct platform_device *pdev)
+{
+	int i;
+	struct sccnxp_port *s = platform_get_drvdata(pdev);
+
+	devm_free_irq(&pdev->dev, s->irq, s);
+
+	for (i = 0; i < s->uart.nr; i++)
+		uart_remove_one_port(&s->uart, &s->port[i]);
+
+	uart_unregister_driver(&s->uart);
+	platform_set_drvdata(pdev, NULL);
+
+	if (s->pdata.exit)
+		s->pdata.exit();
+
+	return 0;
+}
+
+static const struct platform_device_id sccnxp_id_table[] = {
+	{ "sc2681",	SCCNXP_TYPE_SC2681 },
+	{ "sc2691",	SCCNXP_TYPE_SC2691 },
+	{ "sc2692",	SCCNXP_TYPE_SC2692 },
+	{ "sc2891",	SCCNXP_TYPE_SC2891 },
+	{ "sc2892",	SCCNXP_TYPE_SC2892 },
+	{ "sc28202",	SCCNXP_TYPE_SC28202 },
+	{ "sc68681",	SCCNXP_TYPE_SC68681 },
+	{ "sc68692",	SCCNXP_TYPE_SC68692 },
+};
+MODULE_DEVICE_TABLE(platform, sccnxp_id_table);
+
+static struct platform_driver sccnxp_uart_driver = {
+	.driver = {
+		.name	= SCCNXP_NAME,
+		.owner	= THIS_MODULE,
+	},
+	.probe		= sccnxp_probe,
+	.remove		= __devexit_p(sccnxp_remove),
+	.id_table	= sccnxp_id_table,
+};
+module_platform_driver(sccnxp_uart_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
+MODULE_DESCRIPTION("SCCNXP serial driver");

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