tty: move drivers/serial/ to drivers/tty/serial/

The serial drivers are really just tty drivers, so move them to
drivers/tty/ to make things a bit neater overall.

This is part of the tty/serial driver movement proceedure as proposed by
Arnd Bergmann and approved by everyone involved a number of months ago.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Rogier Wolff <R.E.Wolff@bitwizard.nl>
Cc: Michael H. Warfield <mhw@wittsend.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 1213 insertions, 0 deletions

diff --git a/drivers/tty/serial/max3107.c b/drivers/tty/serial/max3107.c
new file mode 100644
index 000000000000..910870edf708
--- /dev/null
+++ b/drivers/tty/serial/max3107.c
@@ -0,0 +1,1213 @@
+/*
+ *  max3107.c - spi uart protocol driver for Maxim 3107
+ *  Based on max3100.c
+ *	by Christian Pellegrin <chripell@evolware.org>
+ *  and	max3110.c
+ *	by Feng Tang <feng.tang@intel.com>
+ *
+ *  Copyright (C) Aavamobile 2009
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ *  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.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/serial_core.h>
+#include <linux/serial.h>
+#include <linux/gpio.h>
+#include <linux/spi/spi.h>
+#include <linux/freezer.h>
+#include "max3107.h"
+
+static const struct baud_table brg26_ext[] = {
+	{ 300,    MAX3107_BRG26_B300 },
+	{ 600,    MAX3107_BRG26_B600 },
+	{ 1200,   MAX3107_BRG26_B1200 },
+	{ 2400,   MAX3107_BRG26_B2400 },
+	{ 4800,   MAX3107_BRG26_B4800 },
+	{ 9600,   MAX3107_BRG26_B9600 },
+	{ 19200,  MAX3107_BRG26_B19200 },
+	{ 57600,  MAX3107_BRG26_B57600 },
+	{ 115200, MAX3107_BRG26_B115200 },
+	{ 230400, MAX3107_BRG26_B230400 },
+	{ 460800, MAX3107_BRG26_B460800 },
+	{ 921600, MAX3107_BRG26_B921600 },
+	{ 0, 0 }
+};
+
+static const struct baud_table brg13_int[] = {
+	{ 300,    MAX3107_BRG13_IB300 },
+	{ 600,    MAX3107_BRG13_IB600 },
+	{ 1200,   MAX3107_BRG13_IB1200 },
+	{ 2400,   MAX3107_BRG13_IB2400 },
+	{ 4800,   MAX3107_BRG13_IB4800 },
+	{ 9600,   MAX3107_BRG13_IB9600 },
+	{ 19200,  MAX3107_BRG13_IB19200 },
+	{ 57600,  MAX3107_BRG13_IB57600 },
+	{ 115200, MAX3107_BRG13_IB115200 },
+	{ 230400, MAX3107_BRG13_IB230400 },
+	{ 460800, MAX3107_BRG13_IB460800 },
+	{ 921600, MAX3107_BRG13_IB921600 },
+	{ 0, 0 }
+};
+
+static u32 get_new_brg(int baud, struct max3107_port *s)
+{
+	int i;
+	const struct baud_table *baud_tbl = s->baud_tbl;
+
+	for (i = 0; i < 13; i++) {
+		if (baud == baud_tbl[i].baud)
+			return baud_tbl[i].new_brg;
+	}
+
+	return 0;
+}
+
+/* Perform SPI transfer for write/read of device register(s) */
+int max3107_rw(struct max3107_port *s, u8 *tx, u8 *rx, int len)
+{
+	struct spi_message spi_msg;
+	struct spi_transfer spi_xfer;
+
+	/* Initialize SPI ,message */
+	spi_message_init(&spi_msg);
+
+	/* Initialize SPI transfer */
+	memset(&spi_xfer, 0, sizeof spi_xfer);
+	spi_xfer.len = len;
+	spi_xfer.tx_buf = tx;
+	spi_xfer.rx_buf = rx;
+	spi_xfer.speed_hz = MAX3107_SPI_SPEED;
+
+	/* Add SPI transfer to SPI message */
+	spi_message_add_tail(&spi_xfer, &spi_msg);
+
+#ifdef DBG_TRACE_SPI_DATA
+	{
+		int i;
+		pr_info("tx len %d:\n", spi_xfer.len);
+		for (i = 0 ; i < spi_xfer.len && i < 32 ; i++)
+			pr_info(" %x", ((u8 *)spi_xfer.tx_buf)[i]);
+		pr_info("\n");
+	}
+#endif
+
+	/* Perform synchronous SPI transfer */
+	if (spi_sync(s->spi, &spi_msg)) {
+		dev_err(&s->spi->dev, "spi_sync failure\n");
+		return -EIO;
+	}
+
+#ifdef DBG_TRACE_SPI_DATA
+	if (spi_xfer.rx_buf) {
+		int i;
+		pr_info("rx len %d:\n", spi_xfer.len);
+		for (i = 0 ; i < spi_xfer.len && i < 32 ; i++)
+			pr_info(" %x", ((u8 *)spi_xfer.rx_buf)[i]);
+		pr_info("\n");
+	}
+#endif
+	return 0;
+}
+EXPORT_SYMBOL_GPL(max3107_rw);
+
+/* Puts received data to circular buffer */
+static void put_data_to_circ_buf(struct max3107_port *s, unsigned char *data,
+					int len)
+{
+	struct uart_port *port = &s->port;
+	struct tty_struct *tty;
+
+	if (!port->state)
+		return;
+
+	tty = port->state->port.tty;
+	if (!tty)
+		return;
+
+	/* Insert received data */
+	tty_insert_flip_string(tty, data, len);
+	/* Update RX counter */
+	port->icount.rx += len;
+}
+
+/* Handle data receiving */
+static void max3107_handlerx(struct max3107_port *s, u16 rxlvl)
+{
+	int i;
+	int j;
+	int len;				/* SPI transfer buffer length */
+	u16 *buf;
+	u8 *valid_str;
+
+	if (!s->rx_enabled)
+		/* RX is disabled */
+		return;
+
+	if (rxlvl == 0) {
+		/* RX fifo is empty */
+		return;
+	} else if (rxlvl >= MAX3107_RX_FIFO_SIZE) {
+		dev_warn(&s->spi->dev, "Possible RX FIFO overrun %d\n", rxlvl);
+		/* Ensure sanity of RX level */
+		rxlvl = MAX3107_RX_FIFO_SIZE;
+	}
+	if ((s->rxbuf == 0) || (s->rxstr == 0)) {
+		dev_warn(&s->spi->dev, "Rx buffer/str isn't ready\n");
+		return;
+	}
+	buf = s->rxbuf;
+	valid_str = s->rxstr;
+	while (rxlvl) {
+		pr_debug("rxlvl %d\n", rxlvl);
+		/* Clear buffer */
+		memset(buf, 0, sizeof(u16) * (MAX3107_RX_FIFO_SIZE + 2));
+		len = 0;
+		if (s->irqen_reg & MAX3107_IRQ_RXFIFO_BIT) {
+			/* First disable RX FIFO interrupt */
+			pr_debug("Disabling RX INT\n");
+			buf[0] = (MAX3107_WRITE_BIT | MAX3107_IRQEN_REG);
+			s->irqen_reg &= ~MAX3107_IRQ_RXFIFO_BIT;
+			buf[0] |= s->irqen_reg;
+			len++;
+		}
+		/* Just increase the length by amount of words in FIFO since
+		 * buffer was zeroed and SPI transfer of 0x0000 means reading
+		 * from RX FIFO
+		 */
+		len += rxlvl;
+		/* Append RX level query */
+		buf[len] = MAX3107_RXFIFOLVL_REG;
+		len++;
+
+		/* Perform the SPI transfer */
+		if (max3107_rw(s, (u8 *)buf, (u8 *)buf, len * 2)) {
+			dev_err(&s->spi->dev, "SPI transfer for RX h failed\n");
+			return;
+		}
+
+		/* Skip RX FIFO interrupt disabling word if it was added */
+		j = ((len - 1) - rxlvl);
+		/* Read received words */
+		for (i = 0; i < rxlvl; i++, j++)
+			valid_str[i] = (u8)buf[j];
+		put_data_to_circ_buf(s, valid_str, rxlvl);
+		/* Get new RX level */
+		rxlvl = (buf[len - 1] & MAX3107_SPI_RX_DATA_MASK);
+	}
+
+	if (s->rx_enabled) {
+		/* RX still enabled, re-enable RX FIFO interrupt */
+		pr_debug("Enabling RX INT\n");
+		buf[0] = (MAX3107_WRITE_BIT | MAX3107_IRQEN_REG);
+		s->irqen_reg |= MAX3107_IRQ_RXFIFO_BIT;
+		buf[0] |= s->irqen_reg;
+		if (max3107_rw(s, (u8 *)buf, NULL, 2))
+			dev_err(&s->spi->dev, "RX FIFO INT enabling failed\n");
+	}
+
+	/* Push the received data to receivers */
+	if (s->port.state->port.tty)
+		tty_flip_buffer_push(s->port.state->port.tty);
+}
+
+
+/* Handle data sending */
+static void max3107_handletx(struct max3107_port *s)
+{
+	struct circ_buf *xmit = &s->port.state->xmit;
+	int i;
+	unsigned long flags;
+	int len;				/* SPI transfer buffer length */
+	u16 *buf;
+
+	if (!s->tx_fifo_empty)
+		/* Don't send more data before previous data is sent */
+		return;
+
+	if (uart_circ_empty(xmit) || uart_tx_stopped(&s->port))
+		/* No data to send or TX is stopped */
+		return;
+
+	if (!s->txbuf) {
+		dev_warn(&s->spi->dev, "Txbuf isn't ready\n");
+		return;
+	}
+	buf = s->txbuf;
+	/* Get length of data pending in circular buffer */
+	len = uart_circ_chars_pending(xmit);
+	if (len) {
+		/* Limit to size of TX FIFO */
+		if (len > MAX3107_TX_FIFO_SIZE)
+			len = MAX3107_TX_FIFO_SIZE;
+
+		pr_debug("txlen %d\n", len);
+
+		/* Update TX counter */
+		s->port.icount.tx += len;
+
+		/* TX FIFO will no longer be empty */
+		s->tx_fifo_empty = 0;
+
+		i = 0;
+		if (s->irqen_reg & MAX3107_IRQ_TXEMPTY_BIT) {
+			/* First disable TX empty interrupt */
+			pr_debug("Disabling TE INT\n");
+			buf[i] = (MAX3107_WRITE_BIT | MAX3107_IRQEN_REG);
+			s->irqen_reg &= ~MAX3107_IRQ_TXEMPTY_BIT;
+			buf[i] |= s->irqen_reg;
+			i++;
+			len++;
+		}
+		/* Add data to send */
+		spin_lock_irqsave(&s->port.lock, flags);
+		for ( ; i < len ; i++) {
+			buf[i] = (MAX3107_WRITE_BIT | MAX3107_THR_REG);
+			buf[i] |= ((u16)xmit->buf[xmit->tail] &
+						MAX3107_SPI_TX_DATA_MASK);
+			xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+		}
+		spin_unlock_irqrestore(&s->port.lock, flags);
+		if (!(s->irqen_reg & MAX3107_IRQ_TXEMPTY_BIT)) {
+			/* Enable TX empty interrupt */
+			pr_debug("Enabling TE INT\n");
+			buf[i] = (MAX3107_WRITE_BIT | MAX3107_IRQEN_REG);
+			s->irqen_reg |= MAX3107_IRQ_TXEMPTY_BIT;
+			buf[i] |= s->irqen_reg;
+			i++;
+			len++;
+		}
+		if (!s->tx_enabled) {
+			/* Enable TX */
+			pr_debug("Enable TX\n");
+			buf[i] = (MAX3107_WRITE_BIT | MAX3107_MODE1_REG);
+			spin_lock_irqsave(&s->data_lock, flags);
+			s->mode1_reg &= ~MAX3107_MODE1_TXDIS_BIT;
+			buf[i] |= s->mode1_reg;
+			spin_unlock_irqrestore(&s->data_lock, flags);
+			s->tx_enabled = 1;
+			i++;
+			len++;
+		}
+
+		/* Perform the SPI transfer */
+		if (max3107_rw(s, (u8 *)buf, NULL, len*2)) {
+			dev_err(&s->spi->dev,
+				"SPI transfer TX handling failed\n");
+			return;
+		}
+	}
+
+	/* Indicate wake up if circular buffer is getting low on data */
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+		uart_write_wakeup(&s->port);
+
+}
+
+/* Handle interrupts
+ * Also reads and returns current RX FIFO level
+ */
+static u16 handle_interrupt(struct max3107_port *s)
+{
+	u16 buf[4];	/* Buffer for SPI transfers */
+	u8 irq_status;
+	u16 rx_level;
+	unsigned long flags;
+
+	/* Read IRQ status register */
+	buf[0] = MAX3107_IRQSTS_REG;
+	/* Read status IRQ status register */
+	buf[1] = MAX3107_STS_IRQSTS_REG;
+	/* Read LSR IRQ status register */
+	buf[2] = MAX3107_LSR_IRQSTS_REG;
+	/* Query RX level */
+	buf[3] = MAX3107_RXFIFOLVL_REG;
+
+	if (max3107_rw(s, (u8 *)buf, (u8 *)buf, 8)) {
+		dev_err(&s->spi->dev,
+			"SPI transfer for INTR handling failed\n");
+		return 0;
+	}
+
+	irq_status = (u8)buf[0];
+	pr_debug("IRQSTS %x\n", irq_status);
+	rx_level = (buf[3] & MAX3107_SPI_RX_DATA_MASK);
+
+	if (irq_status & MAX3107_IRQ_LSR_BIT) {
+		/* LSR interrupt */
+		if (buf[2] & MAX3107_LSR_RXTO_BIT)
+			/* RX timeout interrupt,
+			 * handled by normal RX handling
+			 */
+			pr_debug("RX TO INT\n");
+	}
+
+	if (irq_status & MAX3107_IRQ_TXEMPTY_BIT) {
+		/* Tx empty interrupt,
+		 * disable TX and set tx_fifo_empty flag
+		 */
+		pr_debug("TE INT, disabling TX\n");
+		buf[0] = (MAX3107_WRITE_BIT | MAX3107_MODE1_REG);
+		spin_lock_irqsave(&s->data_lock, flags);
+		s->mode1_reg |= MAX3107_MODE1_TXDIS_BIT;
+		buf[0] |= s->mode1_reg;
+		spin_unlock_irqrestore(&s->data_lock, flags);
+		if (max3107_rw(s, (u8 *)buf, NULL, 2))
+			dev_err(&s->spi->dev, "SPI transfer TX dis failed\n");
+		s->tx_enabled = 0;
+		s->tx_fifo_empty = 1;
+	}
+
+	if (irq_status & MAX3107_IRQ_RXFIFO_BIT)
+		/* RX FIFO interrupt,
+		 * handled by normal RX handling
+		 */
+		pr_debug("RFIFO INT\n");
+
+	/* Return RX level */
+	return rx_level;
+}
+
+/* Trigger work thread*/
+static void max3107_dowork(struct max3107_port *s)
+{
+	if (!work_pending(&s->work) && !freezing(current) && !s->suspended)
+		queue_work(s->workqueue, &s->work);
+	else
+		dev_warn(&s->spi->dev, "interrup isn't serviced normally!\n");
+}
+
+/* Work thread */
+static void max3107_work(struct work_struct *w)
+{
+	struct max3107_port *s = container_of(w, struct max3107_port, work);
+	u16 rxlvl = 0;
+	int len;	/* SPI transfer buffer length */
+	u16 buf[5];	/* Buffer for SPI transfers */
+	unsigned long flags;
+
+	/* Start by reading current RX FIFO level */
+	buf[0] = MAX3107_RXFIFOLVL_REG;
+	if (max3107_rw(s, (u8 *)buf, (u8 *)buf, 2)) {
+		dev_err(&s->spi->dev, "SPI transfer RX lev failed\n");
+		rxlvl = 0;
+	} else {
+		rxlvl = (buf[0] & MAX3107_SPI_RX_DATA_MASK);
+	}
+
+	do {
+		pr_debug("rxlvl %d\n", rxlvl);
+
+		/* Handle RX */
+		max3107_handlerx(s, rxlvl);
+		rxlvl = 0;
+
+		if (s->handle_irq) {
+			/* Handle pending interrupts
+			 * We also get new RX FIFO level since new data may
+			 * have been received while pushing received data to
+			 * receivers
+			 */
+			s->handle_irq = 0;
+			rxlvl = handle_interrupt(s);
+		}
+
+		/* Handle TX */
+		max3107_handletx(s);
+
+		/* Handle configuration changes */
+		len = 0;
+		spin_lock_irqsave(&s->data_lock, flags);
+		if (s->mode1_commit) {
+			pr_debug("mode1_commit\n");
+			buf[len] = (MAX3107_WRITE_BIT | MAX3107_MODE1_REG);
+			buf[len++] |= s->mode1_reg;
+			s->mode1_commit = 0;
+		}
+		if (s->lcr_commit) {
+			pr_debug("lcr_commit\n");
+			buf[len] = (MAX3107_WRITE_BIT | MAX3107_LCR_REG);
+			buf[len++] |= s->lcr_reg;
+			s->lcr_commit = 0;
+		}
+		if (s->brg_commit) {
+			pr_debug("brg_commit\n");
+			buf[len] = (MAX3107_WRITE_BIT | MAX3107_BRGDIVMSB_REG);
+			buf[len++] |= ((s->brg_cfg >> 16) &
+						MAX3107_SPI_TX_DATA_MASK);
+			buf[len] = (MAX3107_WRITE_BIT | MAX3107_BRGDIVLSB_REG);
+			buf[len++] |= ((s->brg_cfg >> 8) &
+						MAX3107_SPI_TX_DATA_MASK);
+			buf[len] = (MAX3107_WRITE_BIT | MAX3107_BRGCFG_REG);
+			buf[len++] |= ((s->brg_cfg) & 0xff);
+			s->brg_commit = 0;
+		}
+		spin_unlock_irqrestore(&s->data_lock, flags);
+
+		if (len > 0) {
+			if (max3107_rw(s, (u8 *)buf, NULL, len * 2))
+				dev_err(&s->spi->dev,
+					"SPI transfer config failed\n");
+		}
+
+		/* Reloop if interrupt handling indicated data in RX FIFO */
+	} while (rxlvl);
+
+}
+
+/* Set sleep mode */
+static void max3107_set_sleep(struct max3107_port *s, int mode)
+{
+	u16 buf[1];	/* Buffer for SPI transfer */
+	unsigned long flags;
+	pr_debug("enter, mode %d\n", mode);
+
+	buf[0] = (MAX3107_WRITE_BIT | MAX3107_MODE1_REG);
+	spin_lock_irqsave(&s->data_lock, flags);
+	switch (mode) {
+	case MAX3107_DISABLE_FORCED_SLEEP:
+			s->mode1_reg &= ~MAX3107_MODE1_FORCESLEEP_BIT;
+			break;
+	case MAX3107_ENABLE_FORCED_SLEEP:
+			s->mode1_reg |= MAX3107_MODE1_FORCESLEEP_BIT;
+			break;
+	case MAX3107_DISABLE_AUTOSLEEP:
+			s->mode1_reg &= ~MAX3107_MODE1_AUTOSLEEP_BIT;
+			break;
+	case MAX3107_ENABLE_AUTOSLEEP:
+			s->mode1_reg |= MAX3107_MODE1_AUTOSLEEP_BIT;
+			break;
+	default:
+		spin_unlock_irqrestore(&s->data_lock, flags);
+		dev_warn(&s->spi->dev, "invalid sleep mode\n");
+		return;
+	}
+	buf[0] |= s->mode1_reg;
+	spin_unlock_irqrestore(&s->data_lock, flags);
+
+	if (max3107_rw(s, (u8 *)buf, NULL, 2))
+		dev_err(&s->spi->dev, "SPI transfer sleep mode failed\n");
+
+	if (mode == MAX3107_DISABLE_AUTOSLEEP ||
+			mode == MAX3107_DISABLE_FORCED_SLEEP)
+		msleep(MAX3107_WAKEUP_DELAY);
+}
+
+/* Perform full register initialization */
+static void max3107_register_init(struct max3107_port *s)
+{
+	u16 buf[11];	/* Buffer for SPI transfers */
+
+	/* 1. Configure baud rate, 9600 as default */
+	s->baud = 9600;
+	/* the below is default*/
+	if (s->ext_clk) {
+		s->brg_cfg = MAX3107_BRG26_B9600;
+		s->baud_tbl = (struct baud_table *)brg26_ext;
+	} else {
+		s->brg_cfg = MAX3107_BRG13_IB9600;
+		s->baud_tbl = (struct baud_table *)brg13_int;
+	}
+
+	if (s->pdata->init)
+		s->pdata->init(s);
+
+	buf[0] = (MAX3107_WRITE_BIT | MAX3107_BRGDIVMSB_REG)
+		| ((s->brg_cfg >> 16) & MAX3107_SPI_TX_DATA_MASK);
+	buf[1] = (MAX3107_WRITE_BIT | MAX3107_BRGDIVLSB_REG)
+		| ((s->brg_cfg >> 8) & MAX3107_SPI_TX_DATA_MASK);
+	buf[2] = (MAX3107_WRITE_BIT | MAX3107_BRGCFG_REG)
+		| ((s->brg_cfg) & 0xff);
+
+	/* 2. Configure LCR register, 8N1 mode by default */
+	s->lcr_reg = MAX3107_LCR_WORD_LEN_8;
+	buf[3] = (MAX3107_WRITE_BIT | MAX3107_LCR_REG)
+		| s->lcr_reg;
+
+	/* 3. Configure MODE 1 register */
+	s->mode1_reg = 0;
+	/* Enable IRQ pin */
+	s->mode1_reg |= MAX3107_MODE1_IRQSEL_BIT;
+	/* Disable TX */
+	s->mode1_reg |= MAX3107_MODE1_TXDIS_BIT;
+	s->tx_enabled = 0;
+	/* RX is enabled */
+	s->rx_enabled = 1;
+	buf[4] = (MAX3107_WRITE_BIT | MAX3107_MODE1_REG)
+		| s->mode1_reg;
+
+	/* 4. Configure MODE 2 register */
+	buf[5] = (MAX3107_WRITE_BIT | MAX3107_MODE2_REG);
+	if (s->loopback) {
+		/* Enable loopback */
+		buf[5] |= MAX3107_MODE2_LOOPBACK_BIT;
+	}
+	/* Reset FIFOs */
+	buf[5] |= MAX3107_MODE2_FIFORST_BIT;
+	s->tx_fifo_empty = 1;
+
+	/* 5. Configure FIFO trigger level register */
+	buf[6] = (MAX3107_WRITE_BIT | MAX3107_FIFOTRIGLVL_REG);
+	/* RX FIFO trigger for 16 words, TX FIFO trigger not used */
+	buf[6] |= (MAX3107_FIFOTRIGLVL_RX(16) | MAX3107_FIFOTRIGLVL_TX(0));
+
+	/* 6. Configure flow control levels */
+	buf[7] = (MAX3107_WRITE_BIT | MAX3107_FLOWLVL_REG);
+	/* Flow control halt level 96, resume level 48 */
+	buf[7] |= (MAX3107_FLOWLVL_RES(48) | MAX3107_FLOWLVL_HALT(96));
+
+	/* 7. Configure flow control */
+	buf[8] = (MAX3107_WRITE_BIT | MAX3107_FLOWCTRL_REG);
+	/* Enable auto CTS and auto RTS flow control */
+	buf[8] |= (MAX3107_FLOWCTRL_AUTOCTS_BIT | MAX3107_FLOWCTRL_AUTORTS_BIT);
+
+	/* 8. Configure RX timeout register */
+	buf[9] = (MAX3107_WRITE_BIT | MAX3107_RXTO_REG);
+	/* Timeout after 48 character intervals */
+	buf[9] |= 0x0030;
+
+	/* 9. Configure LSR interrupt enable register */
+	buf[10] = (MAX3107_WRITE_BIT | MAX3107_LSR_IRQEN_REG);
+	/* Enable RX timeout interrupt */
+	buf[10] |= MAX3107_LSR_RXTO_BIT;
+
+	/* Perform SPI transfer */
+	if (max3107_rw(s, (u8 *)buf, NULL, 22))
+		dev_err(&s->spi->dev, "SPI transfer for init failed\n");
+
+	/* 10. Clear IRQ status register by reading it */
+	buf[0] = MAX3107_IRQSTS_REG;
+
+	/* 11. Configure interrupt enable register */
+	/* Enable LSR interrupt */
+	s->irqen_reg = MAX3107_IRQ_LSR_BIT;
+	/* Enable RX FIFO interrupt */
+	s->irqen_reg |= MAX3107_IRQ_RXFIFO_BIT;
+	buf[1] = (MAX3107_WRITE_BIT | MAX3107_IRQEN_REG)
+		| s->irqen_reg;
+
+	/* 12. Clear FIFO reset that was set in step 6 */
+	buf[2] = (MAX3107_WRITE_BIT | MAX3107_MODE2_REG);
+	if (s->loopback) {
+		/* Keep loopback enabled */
+		buf[2] |= MAX3107_MODE2_LOOPBACK_BIT;
+	}
+
+	/* Perform SPI transfer */
+	if (max3107_rw(s, (u8 *)buf, (u8 *)buf, 6))
+		dev_err(&s->spi->dev, "SPI transfer for init failed\n");
+
+}
+
+/* IRQ handler */
+static irqreturn_t max3107_irq(int irqno, void *dev_id)
+{
+	struct max3107_port *s = dev_id;
+
+	if (irqno != s->spi->irq) {
+		/* Unexpected IRQ */
+		return IRQ_NONE;
+	}
+
+	/* Indicate irq */
+	s->handle_irq = 1;
+
+	/* Trigger work thread */
+	max3107_dowork(s);
+
+	return IRQ_HANDLED;
+}
+
+/* HW suspension function
+ *
+ * Currently autosleep is used to decrease current consumption, alternative
+ * approach would be to set the chip to reset mode if UART is not being
+ * used but that would mess the GPIOs
+ *
+ */
+void max3107_hw_susp(struct max3107_port *s, int suspend)
+{
+	pr_debug("enter, suspend %d\n", suspend);
+
+	if (suspend) {
+		/* Suspend requested,
+		 * enable autosleep to decrease current consumption
+		 */
+		s->suspended = 1;
+		max3107_set_sleep(s, MAX3107_ENABLE_AUTOSLEEP);
+	} else {
+		/* Resume requested,
+		 * disable autosleep
+		 */
+		s->suspended = 0;
+		max3107_set_sleep(s, MAX3107_DISABLE_AUTOSLEEP);
+	}
+}
+EXPORT_SYMBOL_GPL(max3107_hw_susp);
+
+/* Modem status IRQ enabling */
+static void max3107_enable_ms(struct uart_port *port)
+{
+	/* Modem status not supported */
+}
+
+/* Data send function */
+static void max3107_start_tx(struct uart_port *port)
+{
+	struct max3107_port *s = container_of(port, struct max3107_port, port);
+
+	/* Trigger work thread for sending data */
+	max3107_dowork(s);
+}
+
+/* Function for checking that there is no pending transfers */
+static unsigned int max3107_tx_empty(struct uart_port *port)
+{
+	struct max3107_port *s = container_of(port, struct max3107_port, port);
+
+	pr_debug("returning %d\n",
+		  (s->tx_fifo_empty && uart_circ_empty(&s->port.state->xmit)));
+	return s->tx_fifo_empty && uart_circ_empty(&s->port.state->xmit);
+}
+
+/* Function for stopping RX */
+static void max3107_stop_rx(struct uart_port *port)
+{
+	struct max3107_port *s = container_of(port, struct max3107_port, port);
+	unsigned long flags;
+
+	/* Set RX disabled in MODE 1 register */
+	spin_lock_irqsave(&s->data_lock, flags);
+	s->mode1_reg |= MAX3107_MODE1_RXDIS_BIT;
+	s->mode1_commit = 1;
+	spin_unlock_irqrestore(&s->data_lock, flags);
+	/* Set RX disabled */
+	s->rx_enabled = 0;
+	/* Trigger work thread for doing the actual configuration change */
+	max3107_dowork(s);
+}
+
+/* Function for returning control pin states */
+static unsigned int max3107_get_mctrl(struct uart_port *port)
+{
+	/* DCD and DSR are not wired and CTS/RTS is handled automatically
+	 * so just indicate DSR and CAR asserted
+	 */
+	return TIOCM_DSR | TIOCM_CAR;
+}
+
+/* Function for setting control pin states */
+static void max3107_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+	/* DCD and DSR are not wired and CTS/RTS is hadnled automatically
+	 * so do nothing
+	 */
+}
+
+/* Function for configuring UART parameters */
+static void max3107_set_termios(struct uart_port *port,
+				struct ktermios *termios,
+				struct ktermios *old)
+{
+	struct max3107_port *s = container_of(port, struct max3107_port, port);
+	struct tty_struct *tty;
+	int baud;
+	u16 new_lcr = 0;
+	u32 new_brg = 0;
+	unsigned long flags;
+
+	if (!port->state)
+		return;
+
+	tty = port->state->port.tty;
+	if (!tty)
+		return;
+
+	/* Get new LCR register values */
+	/* Word size */
+	if ((termios->c_cflag & CSIZE) == CS7)
+		new_lcr |= MAX3107_LCR_WORD_LEN_7;
+	else
+		new_lcr |= MAX3107_LCR_WORD_LEN_8;
+
+	/* Parity */
+	if (termios->c_cflag & PARENB) {
+		new_lcr |= MAX3107_LCR_PARITY_BIT;
+		if (!(termios->c_cflag & PARODD))
+			new_lcr |= MAX3107_LCR_EVENPARITY_BIT;
+	}
+
+	/* Stop bits */
+	if (termios->c_cflag & CSTOPB) {
+		/* 2 stop bits */
+		new_lcr |= MAX3107_LCR_STOPLEN_BIT;
+	}
+
+	/* Mask termios capabilities we don't support */
+	termios->c_cflag &= ~CMSPAR;
+
+	/* Set status ignore mask */
+	s->port.ignore_status_mask = 0;
+	if (termios->c_iflag & IGNPAR)
+		s->port.ignore_status_mask |= MAX3107_ALL_ERRORS;
+
+	/* Set low latency to immediately handle pushed data */
+	s->port.state->port.tty->low_latency = 1;
+
+	/* Get new baud rate generator configuration */
+	baud = tty_get_baud_rate(tty);
+
+	spin_lock_irqsave(&s->data_lock, flags);
+	new_brg = get_new_brg(baud, s);
+	/* if can't find the corrent config, use previous */
+	if (!new_brg) {
+		baud = s->baud;
+		new_brg = s->brg_cfg;
+	}
+	spin_unlock_irqrestore(&s->data_lock, flags);
+	tty_termios_encode_baud_rate(termios, baud, baud);
+	s->baud = baud;
+
+	/* Update timeout according to new baud rate */
+	uart_update_timeout(port, termios->c_cflag, baud);
+
+	spin_lock_irqsave(&s->data_lock, flags);
+	if (s->lcr_reg != new_lcr) {
+		s->lcr_reg = new_lcr;
+		s->lcr_commit = 1;
+	}
+	if (s->brg_cfg != new_brg) {
+		s->brg_cfg = new_brg;
+		s->brg_commit = 1;
+	}
+	spin_unlock_irqrestore(&s->data_lock, flags);
+
+	/* Trigger work thread for doing the actual configuration change */
+	max3107_dowork(s);
+}
+
+/* Port shutdown function */
+static void max3107_shutdown(struct uart_port *port)
+{
+	struct max3107_port *s = container_of(port, struct max3107_port, port);
+
+	if (s->suspended && s->pdata->hw_suspend)
+		s->pdata->hw_suspend(s, 0);
+
+	/* Free the interrupt */
+	free_irq(s->spi->irq, s);
+
+	if (s->workqueue) {
+		/* Flush and destroy work queue */
+		flush_workqueue(s->workqueue);
+		destroy_workqueue(s->workqueue);
+		s->workqueue = NULL;
+	}
+
+	/* Suspend HW */
+	if (s->pdata->hw_suspend)
+		s->pdata->hw_suspend(s, 1);
+}
+
+/* Port startup function */
+static int max3107_startup(struct uart_port *port)
+{
+	struct max3107_port *s = container_of(port, struct max3107_port, port);
+
+	/* Initialize work queue */
+	s->workqueue = create_freezeable_workqueue("max3107");
+	if (!s->workqueue) {
+		dev_err(&s->spi->dev, "Workqueue creation failed\n");
+		return -EBUSY;
+	}
+	INIT_WORK(&s->work, max3107_work);
+
+	/* Setup IRQ */
+	if (request_irq(s->spi->irq, max3107_irq, IRQF_TRIGGER_FALLING,
+			"max3107", s)) {
+		dev_err(&s->spi->dev, "IRQ reguest failed\n");
+		destroy_workqueue(s->workqueue);
+		s->workqueue = NULL;
+		return -EBUSY;
+	}
+
+	/* Resume HW */
+	if (s->pdata->hw_suspend)
+		s->pdata->hw_suspend(s, 0);
+
+	/* Init registers */
+	max3107_register_init(s);
+
+	return 0;
+}
+
+/* Port type function */
+static const char *max3107_type(struct uart_port *port)
+{
+	struct max3107_port *s = container_of(port, struct max3107_port, port);
+	return s->spi->modalias;
+}
+
+/* Port release function */
+static void max3107_release_port(struct uart_port *port)
+{
+	/* Do nothing */
+}
+
+/* Port request function */
+static int max3107_request_port(struct uart_port *port)
+{
+	/* Do nothing */
+	return 0;
+}
+
+/* Port config function */
+static void max3107_config_port(struct uart_port *port, int flags)
+{
+	struct max3107_port *s = container_of(port, struct max3107_port, port);
+	s->port.type = PORT_MAX3107;
+}
+
+/* Port verify function */
+static int max3107_verify_port(struct uart_port *port,
+				struct serial_struct *ser)
+{
+	if (ser->type == PORT_UNKNOWN || ser->type == PORT_MAX3107)
+		return 0;
+
+	return -EINVAL;
+}
+
+/* Port stop TX function */
+static void max3107_stop_tx(struct uart_port *port)
+{
+	/* Do nothing */
+}
+
+/* Port break control function */
+static void max3107_break_ctl(struct uart_port *port, int break_state)
+{
+	/* We don't support break control, do nothing */
+}
+
+
+/* Port functions */
+static struct uart_ops max3107_ops = {
+	.tx_empty       = max3107_tx_empty,
+	.set_mctrl      = max3107_set_mctrl,
+	.get_mctrl      = max3107_get_mctrl,
+	.stop_tx        = max3107_stop_tx,
+	.start_tx       = max3107_start_tx,
+	.stop_rx        = max3107_stop_rx,
+	.enable_ms      = max3107_enable_ms,
+	.break_ctl      = max3107_break_ctl,
+	.startup        = max3107_startup,
+	.shutdown       = max3107_shutdown,
+	.set_termios    = max3107_set_termios,
+	.type           = max3107_type,
+	.release_port   = max3107_release_port,
+	.request_port   = max3107_request_port,
+	.config_port    = max3107_config_port,
+	.verify_port    = max3107_verify_port,
+};
+
+/* UART driver data */
+static struct uart_driver max3107_uart_driver = {
+	.owner          = THIS_MODULE,
+	.driver_name    = "ttyMAX",
+	.dev_name       = "ttyMAX",
+	.nr             = 1,
+};
+
+static int driver_registered = 0;
+
+
+
+/* 'Generic' platform data */
+static struct max3107_plat generic_plat_data = {
+	.loopback               = 0,
+	.ext_clk                = 1,
+	.hw_suspend		= max3107_hw_susp,
+	.polled_mode            = 0,
+	.poll_time              = 0,
+};
+
+
+/*******************************************************************/
+
+/**
+ *	max3107_probe		-	SPI bus probe entry point
+ *	@spi: the spi device
+ *
+ *	SPI wants us to probe this device and if appropriate claim it.
+ *	Perform any platform specific requirements and then initialise
+ *	the device.
+ */
+
+int max3107_probe(struct spi_device *spi, struct max3107_plat *pdata)
+{
+	struct max3107_port *s;
+	u16 buf[2];	/* Buffer for SPI transfers */
+	int retval;
+
+	pr_info("enter max3107 probe\n");
+
+	/* Allocate port structure */
+	s = kzalloc(sizeof(*s), GFP_KERNEL);
+	if (!s) {
+		pr_err("Allocating port structure failed\n");
+		return -ENOMEM;
+	}
+
+	s->pdata = pdata;
+
+	/* SPI Rx buffer
+	 * +2 for RX FIFO interrupt
+	 * disabling and RX level query
+	 */
+	s->rxbuf = kzalloc(sizeof(u16) * (MAX3107_RX_FIFO_SIZE+2), GFP_KERNEL);
+	if (!s->rxbuf) {
+		pr_err("Allocating RX buffer failed\n");
+		retval = -ENOMEM;
+		goto err_free4;
+	}
+	s->rxstr = kzalloc(sizeof(u8) * MAX3107_RX_FIFO_SIZE, GFP_KERNEL);
+	if (!s->rxstr) {
+		pr_err("Allocating RX buffer failed\n");
+		retval = -ENOMEM;
+		goto err_free3;
+	}
+	/* SPI Tx buffer
+	 * SPI transfer buffer
+	 * +3 for TX FIFO empty
+	 * interrupt disabling and
+	 * enabling and TX enabling
+	 */
+	s->txbuf = kzalloc(sizeof(u16) * MAX3107_TX_FIFO_SIZE + 3, GFP_KERNEL);
+	if (!s->txbuf) {
+		pr_err("Allocating TX buffer failed\n");
+		retval = -ENOMEM;
+		goto err_free2;
+	}
+	/* Initialize shared data lock */
+	spin_lock_init(&s->data_lock);
+
+	/* SPI intializations */
+	dev_set_drvdata(&spi->dev, s);
+	spi->mode = SPI_MODE_0;
+	spi->dev.platform_data = pdata;
+	spi->bits_per_word = 16;
+	s->ext_clk = pdata->ext_clk;
+	s->loopback = pdata->loopback;
+	spi_setup(spi);
+	s->spi = spi;
+
+	/* Check REV ID to ensure we are talking to what we expect */
+	buf[0] = MAX3107_REVID_REG;
+	if (max3107_rw(s, (u8 *)buf, (u8 *)buf, 2)) {
+		dev_err(&s->spi->dev, "SPI transfer for REVID read failed\n");
+		retval = -EIO;
+		goto err_free1;
+	}
+	if ((buf[0] & MAX3107_SPI_RX_DATA_MASK) != MAX3107_REVID1 &&
+		(buf[0] & MAX3107_SPI_RX_DATA_MASK) != MAX3107_REVID2) {
+		dev_err(&s->spi->dev, "REVID %x does not match\n",
+				(buf[0] & MAX3107_SPI_RX_DATA_MASK));
+		retval = -ENODEV;
+		goto err_free1;
+	}
+
+	/* Disable all interrupts */
+	buf[0] = (MAX3107_WRITE_BIT | MAX3107_IRQEN_REG | 0x0000);
+	buf[0] |= 0x0000;
+
+	/* Configure clock source */
+	buf[1] = (MAX3107_WRITE_BIT | MAX3107_CLKSRC_REG);
+	if (s->ext_clk) {
+		/* External clock */
+		buf[1] |= MAX3107_CLKSRC_EXTCLK_BIT;
+	}
+
+	/* PLL bypass ON */
+	buf[1] |= MAX3107_CLKSRC_PLLBYP_BIT;
+
+	/* Perform SPI transfer */
+	if (max3107_rw(s, (u8 *)buf, NULL, 4)) {
+		dev_err(&s->spi->dev, "SPI transfer for init failed\n");
+		retval = -EIO;
+		goto err_free1;
+	}
+
+	/* Register UART driver */
+	if (!driver_registered) {
+		retval = uart_register_driver(&max3107_uart_driver);
+		if (retval) {
+			dev_err(&s->spi->dev, "Registering UART driver failed\n");
+			goto err_free1;
+		}
+		driver_registered = 1;
+	}
+
+	/* Initialize UART port data */
+	s->port.fifosize = 128;
+	s->port.ops = &max3107_ops;
+	s->port.line = 0;
+	s->port.dev = &spi->dev;
+	s->port.uartclk = 9600;
+	s->port.flags = UPF_SKIP_TEST | UPF_BOOT_AUTOCONF;
+	s->port.irq = s->spi->irq;
+	s->port.type = PORT_MAX3107;
+
+	/* Add UART port */
+	retval = uart_add_one_port(&max3107_uart_driver, &s->port);
+	if (retval < 0) {
+		dev_err(&s->spi->dev, "Adding UART port failed\n");
+		goto err_free1;
+	}
+
+	if (pdata->configure) {
+		retval = pdata->configure(s);
+		if (retval < 0)
+			goto err_free1;
+	}
+
+	/* Go to suspend mode */
+	if (pdata->hw_suspend)
+		pdata->hw_suspend(s, 1);
+
+	return 0;
+
+err_free1:
+	kfree(s->txbuf);
+err_free2:
+	kfree(s->rxstr);
+err_free3:
+	kfree(s->rxbuf);
+err_free4:
+	kfree(s);
+	return retval;
+}
+EXPORT_SYMBOL_GPL(max3107_probe);
+
+/* Driver remove function */
+int max3107_remove(struct spi_device *spi)
+{
+	struct max3107_port *s = dev_get_drvdata(&spi->dev);
+
+	pr_info("enter max3107 remove\n");
+
+	/* Remove port */
+	if (uart_remove_one_port(&max3107_uart_driver, &s->port))
+		dev_warn(&s->spi->dev, "Removing UART port failed\n");
+
+
+	/* Free TxRx buffer */
+	kfree(s->rxbuf);
+	kfree(s->rxstr);
+	kfree(s->txbuf);
+
+	/* Free port structure */
+	kfree(s);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(max3107_remove);
+
+/* Driver suspend function */
+int max3107_suspend(struct spi_device *spi, pm_message_t state)
+{
+#ifdef CONFIG_PM
+	struct max3107_port *s = dev_get_drvdata(&spi->dev);
+
+	pr_debug("enter suspend\n");
+
+	/* Suspend UART port */
+	uart_suspend_port(&max3107_uart_driver, &s->port);
+
+	/* Go to suspend mode */
+	if (s->pdata->hw_suspend)
+		s->pdata->hw_suspend(s, 1);
+#endif	/* CONFIG_PM */
+	return 0;
+}
+EXPORT_SYMBOL_GPL(max3107_suspend);
+
+/* Driver resume function */
+int max3107_resume(struct spi_device *spi)
+{
+#ifdef CONFIG_PM
+	struct max3107_port *s = dev_get_drvdata(&spi->dev);
+
+	pr_debug("enter resume\n");
+
+	/* Resume from suspend */
+	if (s->pdata->hw_suspend)
+		s->pdata->hw_suspend(s, 0);
+
+	/* Resume UART port */
+	uart_resume_port(&max3107_uart_driver, &s->port);
+#endif	/* CONFIG_PM */
+	return 0;
+}
+EXPORT_SYMBOL_GPL(max3107_resume);
+
+static int max3107_probe_generic(struct spi_device *spi)
+{
+	return max3107_probe(spi, &generic_plat_data);
+}
+
+/* Spi driver data */
+static struct spi_driver max3107_driver = {
+	.driver = {
+		.name		= "max3107",
+		.bus		= &spi_bus_type,
+		.owner		= THIS_MODULE,
+	},
+	.probe		= max3107_probe_generic,
+	.remove		= __devexit_p(max3107_remove),
+	.suspend	= max3107_suspend,
+	.resume		= max3107_resume,
+};
+
+/* Driver init function */
+static int __init max3107_init(void)
+{
+	pr_info("enter max3107 init\n");
+	return spi_register_driver(&max3107_driver);
+}
+
+/* Driver exit function */
+static void __exit max3107_exit(void)
+{
+	pr_info("enter max3107 exit\n");
+	/* Unregister UART driver */
+	if (driver_registered)
+		uart_unregister_driver(&max3107_uart_driver);
+	spi_unregister_driver(&max3107_driver);
+}
+
+module_init(max3107_init);
+module_exit(max3107_exit);
+
+MODULE_DESCRIPTION("MAX3107 driver");
+MODULE_AUTHOR("Aavamobile");
+MODULE_ALIAS("max3107-spi");
+MODULE_LICENSE("GPL v2");