Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 933 insertions, 0 deletions

diff --git a/drivers/tty/serial/men_z135_uart.c b/drivers/tty/serial/men_z135_uart.c
new file mode 100644
index 000000000..9acae5f8f
--- /dev/null
+++ b/drivers/tty/serial/men_z135_uart.c
@@ -0,0 +1,933 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * MEN 16z135 High Speed UART
+ *
+ * Copyright (C) 2014 MEN Mikroelektronik GmbH (www.men.de)
+ * Author: Johannes Thumshirn <johannes.thumshirn@men.de>
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ":" fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/serial_core.h>
+#include <linux/ioport.h>
+#include <linux/io.h>
+#include <linux/tty_flip.h>
+#include <linux/bitops.h>
+#include <linux/mcb.h>
+
+#define MEN_Z135_MAX_PORTS		12
+#define MEN_Z135_BASECLK		29491200
+#define MEN_Z135_FIFO_SIZE		1024
+#define MEN_Z135_FIFO_WATERMARK		1020
+
+#define MEN_Z135_STAT_REG		0x0
+#define MEN_Z135_RX_RAM			0x4
+#define MEN_Z135_TX_RAM			0x400
+#define MEN_Z135_RX_CTRL		0x800
+#define MEN_Z135_TX_CTRL		0x804
+#define MEN_Z135_CONF_REG		0x808
+#define MEN_Z135_UART_FREQ		0x80c
+#define MEN_Z135_BAUD_REG		0x810
+#define MEN_Z135_TIMEOUT		0x814
+
+#define IRQ_ID(x) ((x) & 0x1f)
+
+#define MEN_Z135_IER_RXCIEN BIT(0)		/* RX Space IRQ */
+#define MEN_Z135_IER_TXCIEN BIT(1)		/* TX Space IRQ */
+#define MEN_Z135_IER_RLSIEN BIT(2)		/* Receiver Line Status IRQ */
+#define MEN_Z135_IER_MSIEN  BIT(3)		/* Modem Status IRQ */
+#define MEN_Z135_ALL_IRQS (MEN_Z135_IER_RXCIEN		\
+				| MEN_Z135_IER_RLSIEN	\
+				| MEN_Z135_IER_MSIEN	\
+				| MEN_Z135_IER_TXCIEN)
+
+#define MEN_Z135_MCR_DTR	BIT(24)
+#define MEN_Z135_MCR_RTS	BIT(25)
+#define MEN_Z135_MCR_OUT1	BIT(26)
+#define MEN_Z135_MCR_OUT2	BIT(27)
+#define MEN_Z135_MCR_LOOP	BIT(28)
+#define MEN_Z135_MCR_RCFC	BIT(29)
+
+#define MEN_Z135_MSR_DCTS	BIT(0)
+#define MEN_Z135_MSR_DDSR	BIT(1)
+#define MEN_Z135_MSR_DRI	BIT(2)
+#define MEN_Z135_MSR_DDCD	BIT(3)
+#define MEN_Z135_MSR_CTS	BIT(4)
+#define MEN_Z135_MSR_DSR	BIT(5)
+#define MEN_Z135_MSR_RI		BIT(6)
+#define MEN_Z135_MSR_DCD	BIT(7)
+
+#define MEN_Z135_LCR_SHIFT 8	/* LCR shift mask */
+
+#define MEN_Z135_WL5 0		/* CS5 */
+#define MEN_Z135_WL6 1		/* CS6 */
+#define MEN_Z135_WL7 2		/* CS7 */
+#define MEN_Z135_WL8 3		/* CS8 */
+
+#define MEN_Z135_STB_SHIFT 2	/* Stopbits */
+#define MEN_Z135_NSTB1 0
+#define MEN_Z135_NSTB2 1
+
+#define MEN_Z135_PEN_SHIFT 3	/* Parity enable */
+#define MEN_Z135_PAR_DIS 0
+#define MEN_Z135_PAR_ENA 1
+
+#define MEN_Z135_PTY_SHIFT 4	/* Parity type */
+#define MEN_Z135_PTY_ODD 0
+#define MEN_Z135_PTY_EVN 1
+
+#define MEN_Z135_LSR_DR BIT(0)
+#define MEN_Z135_LSR_OE BIT(1)
+#define MEN_Z135_LSR_PE BIT(2)
+#define MEN_Z135_LSR_FE BIT(3)
+#define MEN_Z135_LSR_BI BIT(4)
+#define MEN_Z135_LSR_THEP BIT(5)
+#define MEN_Z135_LSR_TEXP BIT(6)
+#define MEN_Z135_LSR_RXFIFOERR BIT(7)
+
+#define MEN_Z135_IRQ_ID_RLS BIT(0)
+#define MEN_Z135_IRQ_ID_RDA BIT(1)
+#define MEN_Z135_IRQ_ID_CTI BIT(2)
+#define MEN_Z135_IRQ_ID_TSA BIT(3)
+#define MEN_Z135_IRQ_ID_MST BIT(4)
+
+#define LCR(x) (((x) >> MEN_Z135_LCR_SHIFT) & 0xff)
+
+#define BYTES_TO_ALIGN(x) ((x) & 0x3)
+
+static int line;
+
+static int txlvl = 5;
+module_param(txlvl, int, S_IRUGO);
+MODULE_PARM_DESC(txlvl, "TX IRQ trigger level 0-7, default 5 (128 byte)");
+
+static int rxlvl = 6;
+module_param(rxlvl, int, S_IRUGO);
+MODULE_PARM_DESC(rxlvl, "RX IRQ trigger level 0-7, default 6 (256 byte)");
+
+static int align;
+module_param(align, int, S_IRUGO);
+MODULE_PARM_DESC(align, "Keep hardware FIFO write pointer aligned, default 0");
+
+static uint rx_timeout;
+module_param(rx_timeout, uint, S_IRUGO);
+MODULE_PARM_DESC(rx_timeout, "RX timeout. "
+		"Timeout in seconds = (timeout_reg * baud_reg * 4) / freq_reg");
+
+struct men_z135_port {
+	struct uart_port port;
+	struct mcb_device *mdev;
+	struct resource *mem;
+	unsigned char *rxbuf;
+	u32 stat_reg;
+	spinlock_t lock;
+	bool automode;
+};
+#define to_men_z135(port) container_of((port), struct men_z135_port, port)
+
+/**
+ * men_z135_reg_set() - Set value in register
+ * @uart: The UART port
+ * @addr: Register address
+ * @val: value to set
+ */
+static inline void men_z135_reg_set(struct men_z135_port *uart,
+				u32 addr, u32 val)
+{
+	struct uart_port *port = &uart->port;
+	unsigned long flags;
+	u32 reg;
+
+	spin_lock_irqsave(&uart->lock, flags);
+
+	reg = ioread32(port->membase + addr);
+	reg |= val;
+	iowrite32(reg, port->membase + addr);
+
+	spin_unlock_irqrestore(&uart->lock, flags);
+}
+
+/**
+ * men_z135_reg_clr() - Unset value in register
+ * @uart: The UART port
+ * @addr: Register address
+ * @val: value to clear
+ */
+static void men_z135_reg_clr(struct men_z135_port *uart,
+				u32 addr, u32 val)
+{
+	struct uart_port *port = &uart->port;
+	unsigned long flags;
+	u32 reg;
+
+	spin_lock_irqsave(&uart->lock, flags);
+
+	reg = ioread32(port->membase + addr);
+	reg &= ~val;
+	iowrite32(reg, port->membase + addr);
+
+	spin_unlock_irqrestore(&uart->lock, flags);
+}
+
+/**
+ * men_z135_handle_modem_status() - Handle change of modem status
+ * @uart: The UART port
+ *
+ * Handle change of modem status register. This is done by reading the "delta"
+ * versions of DCD (Data Carrier Detect) and CTS (Clear To Send).
+ */
+static void men_z135_handle_modem_status(struct men_z135_port *uart)
+{
+	u8 msr;
+
+	msr = (uart->stat_reg >> 8) & 0xff;
+
+	if (msr & MEN_Z135_MSR_DDCD)
+		uart_handle_dcd_change(&uart->port,
+				msr & MEN_Z135_MSR_DCD);
+	if (msr & MEN_Z135_MSR_DCTS)
+		uart_handle_cts_change(&uart->port,
+				msr & MEN_Z135_MSR_CTS);
+}
+
+static void men_z135_handle_lsr(struct men_z135_port *uart)
+{
+	struct uart_port *port = &uart->port;
+	u8 lsr;
+
+	lsr = (uart->stat_reg >> 16) & 0xff;
+
+	if (lsr & MEN_Z135_LSR_OE)
+		port->icount.overrun++;
+	if (lsr & MEN_Z135_LSR_PE)
+		port->icount.parity++;
+	if (lsr & MEN_Z135_LSR_FE)
+		port->icount.frame++;
+	if (lsr & MEN_Z135_LSR_BI) {
+		port->icount.brk++;
+		uart_handle_break(port);
+	}
+}
+
+/**
+ * get_rx_fifo_content() - Get the number of bytes in RX FIFO
+ * @uart: The UART port
+ *
+ * Read RXC register from hardware and return current FIFO fill size.
+ */
+static u16 get_rx_fifo_content(struct men_z135_port *uart)
+{
+	struct uart_port *port = &uart->port;
+	u32 stat_reg;
+	u16 rxc;
+	u8 rxc_lo;
+	u8 rxc_hi;
+
+	stat_reg = ioread32(port->membase + MEN_Z135_STAT_REG);
+	rxc_lo = stat_reg >> 24;
+	rxc_hi = (stat_reg & 0xC0) >> 6;
+
+	rxc = rxc_lo | (rxc_hi << 8);
+
+	return rxc;
+}
+
+/**
+ * men_z135_handle_rx() - RX tasklet routine
+ * @uart: Pointer to struct men_z135_port
+ *
+ * Copy from RX FIFO and acknowledge number of bytes copied.
+ */
+static void men_z135_handle_rx(struct men_z135_port *uart)
+{
+	struct uart_port *port = &uart->port;
+	struct tty_port *tport = &port->state->port;
+	int copied;
+	u16 size;
+	int room;
+
+	size = get_rx_fifo_content(uart);
+
+	if (size == 0)
+		return;
+
+	/* Avoid accidently accessing TX FIFO instead of RX FIFO. Last
+	 * longword in RX FIFO cannot be read.(0x004-0x3FF)
+	 */
+	if (size > MEN_Z135_FIFO_WATERMARK)
+		size = MEN_Z135_FIFO_WATERMARK;
+
+	room = tty_buffer_request_room(tport, size);
+	if (room != size)
+		dev_warn(&uart->mdev->dev,
+			"Not enough room in flip buffer, truncating to %d\n",
+			room);
+
+	if (room == 0)
+		return;
+
+	memcpy_fromio(uart->rxbuf, port->membase + MEN_Z135_RX_RAM, room);
+	/* Be sure to first copy all data and then acknowledge it */
+	mb();
+	iowrite32(room, port->membase +  MEN_Z135_RX_CTRL);
+
+	copied = tty_insert_flip_string(tport, uart->rxbuf, room);
+	if (copied != room)
+		dev_warn(&uart->mdev->dev,
+			"Only copied %d instead of %d bytes\n",
+			copied, room);
+
+	port->icount.rx += copied;
+
+	tty_flip_buffer_push(tport);
+
+}
+
+/**
+ * men_z135_handle_tx() - TX tasklet routine
+ * @uart: Pointer to struct men_z135_port
+ *
+ */
+static void men_z135_handle_tx(struct men_z135_port *uart)
+{
+	struct uart_port *port = &uart->port;
+	struct circ_buf *xmit = &port->state->xmit;
+	u32 txc;
+	u32 wptr;
+	int qlen;
+	int n;
+	int txfree;
+	int head;
+	int tail;
+	int s;
+
+	if (uart_circ_empty(xmit))
+		goto out;
+
+	if (uart_tx_stopped(port))
+		goto out;
+
+	if (port->x_char)
+		goto out;
+
+	/* calculate bytes to copy */
+	qlen = uart_circ_chars_pending(xmit);
+	if (qlen <= 0)
+		goto out;
+
+	wptr = ioread32(port->membase + MEN_Z135_TX_CTRL);
+	txc = (wptr >> 16) & 0x3ff;
+	wptr &= 0x3ff;
+
+	if (txc > MEN_Z135_FIFO_WATERMARK)
+		txc = MEN_Z135_FIFO_WATERMARK;
+
+	txfree = MEN_Z135_FIFO_WATERMARK - txc;
+	if (txfree <= 0) {
+		dev_err(&uart->mdev->dev,
+			"Not enough room in TX FIFO have %d, need %d\n",
+			txfree, qlen);
+		goto irq_en;
+	}
+
+	/* if we're not aligned, it's better to copy only 1 or 2 bytes and
+	 * then the rest.
+	 */
+	if (align && qlen >= 3 && BYTES_TO_ALIGN(wptr))
+		n = 4 - BYTES_TO_ALIGN(wptr);
+	else if (qlen > txfree)
+		n = txfree;
+	else
+		n = qlen;
+
+	if (n <= 0)
+		goto irq_en;
+
+	head = xmit->head & (UART_XMIT_SIZE - 1);
+	tail = xmit->tail & (UART_XMIT_SIZE - 1);
+
+	s = ((head >= tail) ? head : UART_XMIT_SIZE) - tail;
+	n = min(n, s);
+
+	memcpy_toio(port->membase + MEN_Z135_TX_RAM, &xmit->buf[xmit->tail], n);
+	xmit->tail = (xmit->tail + n) & (UART_XMIT_SIZE - 1);
+
+	iowrite32(n & 0x3ff, port->membase + MEN_Z135_TX_CTRL);
+
+	port->icount.tx += n;
+
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+		uart_write_wakeup(port);
+
+irq_en:
+	if (!uart_circ_empty(xmit))
+		men_z135_reg_set(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_TXCIEN);
+	else
+		men_z135_reg_clr(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_TXCIEN);
+
+out:
+	return;
+
+}
+
+/**
+ * men_z135_intr() - Handle legacy IRQs
+ * @irq: The IRQ number
+ * @data: Pointer to UART port
+ *
+ * Check IIR register to find the cause of the interrupt and handle it.
+ * It is possible that multiple interrupts reason bits are set and reading
+ * the IIR is a destructive read, so we always need to check for all possible
+ * interrupts and handle them.
+ */
+static irqreturn_t men_z135_intr(int irq, void *data)
+{
+	struct men_z135_port *uart = (struct men_z135_port *)data;
+	struct uart_port *port = &uart->port;
+	bool handled = false;
+	int irq_id;
+
+	uart->stat_reg = ioread32(port->membase + MEN_Z135_STAT_REG);
+	irq_id = IRQ_ID(uart->stat_reg);
+
+	if (!irq_id)
+		goto out;
+
+	spin_lock(&port->lock);
+	/* It's save to write to IIR[7:6] RXC[9:8] */
+	iowrite8(irq_id, port->membase + MEN_Z135_STAT_REG);
+
+	if (irq_id & MEN_Z135_IRQ_ID_RLS) {
+		men_z135_handle_lsr(uart);
+		handled = true;
+	}
+
+	if (irq_id & (MEN_Z135_IRQ_ID_RDA | MEN_Z135_IRQ_ID_CTI)) {
+		if (irq_id & MEN_Z135_IRQ_ID_CTI)
+			dev_dbg(&uart->mdev->dev, "Character Timeout Indication\n");
+		men_z135_handle_rx(uart);
+		handled = true;
+	}
+
+	if (irq_id & MEN_Z135_IRQ_ID_TSA) {
+		men_z135_handle_tx(uart);
+		handled = true;
+	}
+
+	if (irq_id & MEN_Z135_IRQ_ID_MST) {
+		men_z135_handle_modem_status(uart);
+		handled = true;
+	}
+
+	spin_unlock(&port->lock);
+out:
+	return IRQ_RETVAL(handled);
+}
+
+/**
+ * men_z135_request_irq() - Request IRQ for 16z135 core
+ * @uart: z135 private uart port structure
+ *
+ * Request an IRQ for 16z135 to use. First try using MSI, if it fails
+ * fall back to using legacy interrupts.
+ */
+static int men_z135_request_irq(struct men_z135_port *uart)
+{
+	struct device *dev = &uart->mdev->dev;
+	struct uart_port *port = &uart->port;
+	int err = 0;
+
+	err = request_irq(port->irq, men_z135_intr, IRQF_SHARED,
+			"men_z135_intr", uart);
+	if (err)
+		dev_err(dev, "Error %d getting interrupt\n", err);
+
+	return err;
+}
+
+/**
+ * men_z135_tx_empty() - Handle tx_empty call
+ * @port: The UART port
+ *
+ * This function tests whether the TX FIFO and shifter for the port
+ * described by @port is empty.
+ */
+static unsigned int men_z135_tx_empty(struct uart_port *port)
+{
+	u32 wptr;
+	u16 txc;
+
+	wptr = ioread32(port->membase + MEN_Z135_TX_CTRL);
+	txc = (wptr >> 16) & 0x3ff;
+
+	if (txc == 0)
+		return TIOCSER_TEMT;
+	else
+		return 0;
+}
+
+/**
+ * men_z135_set_mctrl() - Set modem control lines
+ * @port: The UART port
+ * @mctrl: The modem control lines
+ *
+ * This function sets the modem control lines for a port described by @port
+ * to the state described by @mctrl
+ */
+static void men_z135_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+	u32 old;
+	u32 conf_reg;
+
+	conf_reg = old = ioread32(port->membase + MEN_Z135_CONF_REG);
+	if (mctrl & TIOCM_RTS)
+		conf_reg |= MEN_Z135_MCR_RTS;
+	else
+		conf_reg &= ~MEN_Z135_MCR_RTS;
+
+	if (mctrl & TIOCM_DTR)
+		conf_reg |= MEN_Z135_MCR_DTR;
+	else
+		conf_reg &= ~MEN_Z135_MCR_DTR;
+
+	if (mctrl & TIOCM_OUT1)
+		conf_reg |= MEN_Z135_MCR_OUT1;
+	else
+		conf_reg &= ~MEN_Z135_MCR_OUT1;
+
+	if (mctrl & TIOCM_OUT2)
+		conf_reg |= MEN_Z135_MCR_OUT2;
+	else
+		conf_reg &= ~MEN_Z135_MCR_OUT2;
+
+	if (mctrl & TIOCM_LOOP)
+		conf_reg |= MEN_Z135_MCR_LOOP;
+	else
+		conf_reg &= ~MEN_Z135_MCR_LOOP;
+
+	if (conf_reg != old)
+		iowrite32(conf_reg, port->membase + MEN_Z135_CONF_REG);
+}
+
+/**
+ * men_z135_get_mctrl() - Get modem control lines
+ * @port: The UART port
+ *
+ * Retruns the current state of modem control inputs.
+ */
+static unsigned int men_z135_get_mctrl(struct uart_port *port)
+{
+	unsigned int mctrl = 0;
+	u8 msr;
+
+	msr = ioread8(port->membase + MEN_Z135_STAT_REG + 1);
+
+	if (msr & MEN_Z135_MSR_CTS)
+		mctrl |= TIOCM_CTS;
+	if (msr & MEN_Z135_MSR_DSR)
+		mctrl |= TIOCM_DSR;
+	if (msr & MEN_Z135_MSR_RI)
+		mctrl |= TIOCM_RI;
+	if (msr & MEN_Z135_MSR_DCD)
+		mctrl |= TIOCM_CAR;
+
+	return mctrl;
+}
+
+/**
+ * men_z135_stop_tx() - Stop transmitting characters
+ * @port: The UART port
+ *
+ * Stop transmitting characters. This might be due to CTS line becomming
+ * inactive or the tty layer indicating we want to stop transmission due to
+ * an XOFF character.
+ */
+static void men_z135_stop_tx(struct uart_port *port)
+{
+	struct men_z135_port *uart = to_men_z135(port);
+
+	men_z135_reg_clr(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_TXCIEN);
+}
+
+/*
+ * men_z135_disable_ms() - Disable Modem Status
+ * port: The UART port
+ *
+ * Enable Modem Status IRQ.
+ */
+static void men_z135_disable_ms(struct uart_port *port)
+{
+	struct men_z135_port *uart = to_men_z135(port);
+
+	men_z135_reg_clr(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_MSIEN);
+}
+
+/**
+ * men_z135_start_tx() - Start transmitting characters
+ * @port: The UART port
+ *
+ * Start transmitting character. This actually doesn't transmit anything, but
+ * fires off the TX tasklet.
+ */
+static void men_z135_start_tx(struct uart_port *port)
+{
+	struct men_z135_port *uart = to_men_z135(port);
+
+	if (uart->automode)
+		men_z135_disable_ms(port);
+
+	men_z135_handle_tx(uart);
+}
+
+/**
+ * men_z135_stop_rx() - Stop receiving characters
+ * @port: The UART port
+ *
+ * Stop receiving characters; the port is in the process of being closed.
+ */
+static void men_z135_stop_rx(struct uart_port *port)
+{
+	struct men_z135_port *uart = to_men_z135(port);
+
+	men_z135_reg_clr(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_RXCIEN);
+}
+
+/**
+ * men_z135_enable_ms() - Enable Modem Status
+ * @port: the port
+ *
+ * Enable Modem Status IRQ.
+ */
+static void men_z135_enable_ms(struct uart_port *port)
+{
+	struct men_z135_port *uart = to_men_z135(port);
+
+	men_z135_reg_set(uart, MEN_Z135_CONF_REG, MEN_Z135_IER_MSIEN);
+}
+
+static int men_z135_startup(struct uart_port *port)
+{
+	struct men_z135_port *uart = to_men_z135(port);
+	int err;
+	u32 conf_reg = 0;
+
+	err = men_z135_request_irq(uart);
+	if (err)
+		return -ENODEV;
+
+	conf_reg = ioread32(port->membase + MEN_Z135_CONF_REG);
+
+	/* Activate all but TX space available IRQ */
+	conf_reg |= MEN_Z135_ALL_IRQS & ~MEN_Z135_IER_TXCIEN;
+	conf_reg &= ~(0xff << 16);
+	conf_reg |= (txlvl << 16);
+	conf_reg |= (rxlvl << 20);
+
+	iowrite32(conf_reg, port->membase + MEN_Z135_CONF_REG);
+
+	if (rx_timeout)
+		iowrite32(rx_timeout, port->membase + MEN_Z135_TIMEOUT);
+
+	return 0;
+}
+
+static void men_z135_shutdown(struct uart_port *port)
+{
+	struct men_z135_port *uart = to_men_z135(port);
+	u32 conf_reg = 0;
+
+	conf_reg |= MEN_Z135_ALL_IRQS;
+
+	men_z135_reg_clr(uart, MEN_Z135_CONF_REG, conf_reg);
+
+	free_irq(uart->port.irq, uart);
+}
+
+static void men_z135_set_termios(struct uart_port *port,
+				struct ktermios *termios,
+				struct ktermios *old)
+{
+	struct men_z135_port *uart = to_men_z135(port);
+	unsigned int baud;
+	u32 conf_reg;
+	u32 bd_reg;
+	u32 uart_freq;
+	u8 lcr;
+
+	conf_reg = ioread32(port->membase + MEN_Z135_CONF_REG);
+	lcr = LCR(conf_reg);
+
+	/* byte size */
+	switch (termios->c_cflag & CSIZE) {
+	case CS5:
+		lcr |= MEN_Z135_WL5;
+		break;
+	case CS6:
+		lcr |= MEN_Z135_WL6;
+		break;
+	case CS7:
+		lcr |= MEN_Z135_WL7;
+		break;
+	case CS8:
+		lcr |= MEN_Z135_WL8;
+		break;
+	}
+
+	/* stop bits */
+	if (termios->c_cflag & CSTOPB)
+		lcr |= MEN_Z135_NSTB2 << MEN_Z135_STB_SHIFT;
+
+	/* parity */
+	if (termios->c_cflag & PARENB) {
+		lcr |= MEN_Z135_PAR_ENA << MEN_Z135_PEN_SHIFT;
+
+		if (termios->c_cflag & PARODD)
+			lcr |= MEN_Z135_PTY_ODD << MEN_Z135_PTY_SHIFT;
+		else
+			lcr |= MEN_Z135_PTY_EVN << MEN_Z135_PTY_SHIFT;
+	} else
+		lcr |= MEN_Z135_PAR_DIS << MEN_Z135_PEN_SHIFT;
+
+	conf_reg |= MEN_Z135_IER_MSIEN;
+	if (termios->c_cflag & CRTSCTS) {
+		conf_reg |= MEN_Z135_MCR_RCFC;
+		uart->automode = true;
+		termios->c_cflag &= ~CLOCAL;
+	} else {
+		conf_reg &= ~MEN_Z135_MCR_RCFC;
+		uart->automode = false;
+	}
+
+	termios->c_cflag &= ~CMSPAR; /* Mark/Space parity is not supported */
+
+	conf_reg |= lcr << MEN_Z135_LCR_SHIFT;
+	iowrite32(conf_reg, port->membase + MEN_Z135_CONF_REG);
+
+	uart_freq = ioread32(port->membase + MEN_Z135_UART_FREQ);
+	if (uart_freq == 0)
+		uart_freq = MEN_Z135_BASECLK;
+
+	baud = uart_get_baud_rate(port, termios, old, 0, uart_freq / 16);
+
+	spin_lock_irq(&port->lock);
+	if (tty_termios_baud_rate(termios))
+		tty_termios_encode_baud_rate(termios, baud, baud);
+
+	bd_reg = uart_freq / (4 * baud);
+	iowrite32(bd_reg, port->membase + MEN_Z135_BAUD_REG);
+
+	uart_update_timeout(port, termios->c_cflag, baud);
+	spin_unlock_irq(&port->lock);
+}
+
+static const char *men_z135_type(struct uart_port *port)
+{
+	return KBUILD_MODNAME;
+}
+
+static void men_z135_release_port(struct uart_port *port)
+{
+	struct men_z135_port *uart = to_men_z135(port);
+
+	iounmap(port->membase);
+	port->membase = NULL;
+
+	mcb_release_mem(uart->mem);
+}
+
+static int men_z135_request_port(struct uart_port *port)
+{
+	struct men_z135_port *uart = to_men_z135(port);
+	struct mcb_device *mdev = uart->mdev;
+	struct resource *mem;
+
+	mem = mcb_request_mem(uart->mdev, dev_name(&mdev->dev));
+	if (IS_ERR(mem))
+		return PTR_ERR(mem);
+
+	port->mapbase = mem->start;
+	uart->mem = mem;
+
+	port->membase = ioremap(mem->start, resource_size(mem));
+	if (port->membase == NULL) {
+		mcb_release_mem(mem);
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static void men_z135_config_port(struct uart_port *port, int type)
+{
+	port->type = PORT_MEN_Z135;
+	men_z135_request_port(port);
+}
+
+static int men_z135_verify_port(struct uart_port *port,
+				struct serial_struct *serinfo)
+{
+	return -EINVAL;
+}
+
+static const struct uart_ops men_z135_ops = {
+	.tx_empty = men_z135_tx_empty,
+	.set_mctrl = men_z135_set_mctrl,
+	.get_mctrl = men_z135_get_mctrl,
+	.stop_tx = men_z135_stop_tx,
+	.start_tx = men_z135_start_tx,
+	.stop_rx = men_z135_stop_rx,
+	.enable_ms = men_z135_enable_ms,
+	.startup = men_z135_startup,
+	.shutdown = men_z135_shutdown,
+	.set_termios = men_z135_set_termios,
+	.type = men_z135_type,
+	.release_port = men_z135_release_port,
+	.request_port = men_z135_request_port,
+	.config_port = men_z135_config_port,
+	.verify_port = men_z135_verify_port,
+};
+
+static struct uart_driver men_z135_driver = {
+	.owner = THIS_MODULE,
+	.driver_name = KBUILD_MODNAME,
+	.dev_name = "ttyHSU",
+	.major = 0,
+	.minor = 0,
+	.nr = MEN_Z135_MAX_PORTS,
+};
+
+/**
+ * men_z135_probe() - Probe a z135 instance
+ * @mdev: The MCB device
+ * @id: The MCB device ID
+ *
+ * men_z135_probe does the basic setup of hardware resources and registers the
+ * new uart port to the tty layer.
+ */
+static int men_z135_probe(struct mcb_device *mdev,
+			const struct mcb_device_id *id)
+{
+	struct men_z135_port *uart;
+	struct resource *mem;
+	struct device *dev;
+	int err;
+
+	dev = &mdev->dev;
+
+	uart = devm_kzalloc(dev, sizeof(struct men_z135_port), GFP_KERNEL);
+	if (!uart)
+		return -ENOMEM;
+
+	uart->rxbuf = (unsigned char *)__get_free_page(GFP_KERNEL);
+	if (!uart->rxbuf)
+		return -ENOMEM;
+
+	mem = &mdev->mem;
+
+	mcb_set_drvdata(mdev, uart);
+
+	uart->port.uartclk = MEN_Z135_BASECLK * 16;
+	uart->port.fifosize = MEN_Z135_FIFO_SIZE;
+	uart->port.iotype = UPIO_MEM;
+	uart->port.ops = &men_z135_ops;
+	uart->port.irq = mcb_get_irq(mdev);
+	uart->port.iotype = UPIO_MEM;
+	uart->port.flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP;
+	uart->port.line = line++;
+	uart->port.dev = dev;
+	uart->port.type = PORT_MEN_Z135;
+	uart->port.mapbase = mem->start;
+	uart->port.membase = NULL;
+	uart->mdev = mdev;
+
+	spin_lock_init(&uart->lock);
+
+	err = uart_add_one_port(&men_z135_driver, &uart->port);
+	if (err)
+		goto err;
+
+	return 0;
+
+err:
+	free_page((unsigned long) uart->rxbuf);
+	dev_err(dev, "Failed to add UART: %d\n", err);
+
+	return err;
+}
+
+/**
+ * men_z135_remove() - Remove a z135 instance from the system
+ *
+ * @mdev: The MCB device
+ */
+static void men_z135_remove(struct mcb_device *mdev)
+{
+	struct men_z135_port *uart = mcb_get_drvdata(mdev);
+
+	line--;
+	uart_remove_one_port(&men_z135_driver, &uart->port);
+	free_page((unsigned long) uart->rxbuf);
+}
+
+static const struct mcb_device_id men_z135_ids[] = {
+	{ .device = 0x87 },
+	{ }
+};
+MODULE_DEVICE_TABLE(mcb, men_z135_ids);
+
+static struct mcb_driver mcb_driver = {
+	.driver = {
+		.name = "z135-uart",
+		.owner = THIS_MODULE,
+	},
+	.probe = men_z135_probe,
+	.remove = men_z135_remove,
+	.id_table = men_z135_ids,
+};
+
+/**
+ * men_z135_init() - Driver Registration Routine
+ *
+ * men_z135_init is the first routine called when the driver is loaded. All it
+ * does is register with the legacy MEN Chameleon subsystem.
+ */
+static int __init men_z135_init(void)
+{
+	int err;
+
+	err = uart_register_driver(&men_z135_driver);
+	if (err) {
+		pr_err("Failed to register UART: %d\n", err);
+		return err;
+	}
+
+	err = mcb_register_driver(&mcb_driver);
+	if  (err) {
+		pr_err("Failed to register MCB driver: %d\n", err);
+		uart_unregister_driver(&men_z135_driver);
+		return err;
+	}
+
+	return 0;
+}
+module_init(men_z135_init);
+
+/**
+ * men_z135_exit() - Driver Exit Routine
+ *
+ * men_z135_exit is called just before the driver is removed from memory.
+ */
+static void __exit men_z135_exit(void)
+{
+	mcb_unregister_driver(&mcb_driver);
+	uart_unregister_driver(&men_z135_driver);
+}
+module_exit(men_z135_exit);
+
+MODULE_AUTHOR("Johannes Thumshirn <johannes.thumshirn@men.de>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("MEN 16z135 High Speed UART");
+MODULE_ALIAS("mcb:16z135");
+MODULE_IMPORT_NS(MCB);