Initial import

1 files changed, 1133 insertions, 0 deletions

diff --git a/drivers/net/irda/stir4200.c b/drivers/net/irda/stir4200.c
new file mode 100644
index 000000000..83cc48a01
--- /dev/null
+++ b/drivers/net/irda/stir4200.c
@@ -0,0 +1,1133 @@
+/*****************************************************************************
+*
+* Filename:      stir4200.c
+* Version:       0.4
+* Description:   Irda SigmaTel USB Dongle
+* Status:        Experimental
+* Author:        Stephen Hemminger <shemminger@osdl.org>
+*
+*  	Based on earlier driver by Paul Stewart <stewart@parc.com>
+*
+*	Copyright (C) 2000, Roman Weissgaerber <weissg@vienna.at>
+*	Copyright (C) 2001, Dag Brattli <dag@brattli.net>
+*	Copyright (C) 2001, Jean Tourrilhes <jt@hpl.hp.com>
+*	Copyright (C) 2004, Stephen Hemminger <shemminger@osdl.org>
+*
+*	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.
+*
+*	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., 675 Mass Ave, Cambridge, MA 02139, USA.
+*
+*****************************************************************************/
+
+/*
+ * This dongle does no framing, and requires polling to receive the
+ * data.  The STIr4200 has bulk in and out endpoints just like
+ * usr-irda devices, but the data it sends and receives is raw; like
+ * irtty, it needs to call the wrap and unwrap functions to add and
+ * remove SOF/BOF and escape characters to/from the frame.
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+
+#include <linux/kernel.h>
+#include <linux/ktime.h>
+#include <linux/types.h>
+#include <linux/time.h>
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/usb.h>
+#include <linux/crc32.h>
+#include <linux/kthread.h>
+#include <linux/freezer.h>
+#include <net/irda/irda.h>
+#include <net/irda/irda_device.h>
+#include <net/irda/wrapper.h>
+#include <net/irda/crc.h>
+#include <asm/byteorder.h>
+#include <asm/unaligned.h>
+
+MODULE_AUTHOR("Stephen Hemminger <shemminger@linux-foundation.org>");
+MODULE_DESCRIPTION("IrDA-USB Dongle Driver for SigmaTel STIr4200");
+MODULE_LICENSE("GPL");
+
+static int qos_mtt_bits = 0x07;	/* 1 ms or more */
+module_param(qos_mtt_bits, int, 0);
+MODULE_PARM_DESC(qos_mtt_bits, "Minimum Turn Time");
+
+static int rx_sensitivity = 1;	/* FIR 0..4, SIR 0..6 */
+module_param(rx_sensitivity, int, 0);
+MODULE_PARM_DESC(rx_sensitivity, "Set Receiver sensitivity (0-6, 0 is most sensitive)");
+
+static int tx_power = 0;	/* 0 = highest ... 3 = lowest */
+module_param(tx_power, int, 0);
+MODULE_PARM_DESC(tx_power, "Set Transmitter power (0-3, 0 is highest power)");
+
+#define STIR_IRDA_HEADER  	4
+#define CTRL_TIMEOUT		100	   /* milliseconds */
+#define TRANSMIT_TIMEOUT	200	   /* milliseconds */
+#define STIR_FIFO_SIZE		4096
+#define FIFO_REGS_SIZE		3
+
+enum FirChars {
+	FIR_CE   = 0x7d,
+	FIR_XBOF = 0x7f,
+	FIR_EOF  = 0x7e,
+};
+
+enum StirRequests {
+	REQ_WRITE_REG =		0x00,
+	REQ_READ_REG =		0x01,
+	REQ_READ_ROM =		0x02,
+	REQ_WRITE_SINGLE =	0x03,
+};
+
+/* Register offsets */
+enum StirRegs {
+	REG_RSVD=0,
+	REG_MODE,
+	REG_PDCLK,
+	REG_CTRL1,
+	REG_CTRL2,
+	REG_FIFOCTL,
+	REG_FIFOLSB,
+	REG_FIFOMSB,
+	REG_DPLL,
+	REG_IRDIG,
+	REG_TEST=15,
+};
+
+enum StirModeMask {
+	MODE_FIR = 0x80,
+	MODE_SIR = 0x20,
+	MODE_ASK = 0x10,
+	MODE_FASTRX = 0x08,
+	MODE_FFRSTEN = 0x04,
+	MODE_NRESET = 0x02,
+	MODE_2400 = 0x01,
+};
+
+enum StirPdclkMask {
+	PDCLK_4000000 = 0x02,
+	PDCLK_115200 = 0x09,
+	PDCLK_57600 = 0x13,
+	PDCLK_38400 = 0x1D,
+	PDCLK_19200 = 0x3B,
+	PDCLK_9600 = 0x77,
+	PDCLK_2400 = 0xDF,
+};
+
+enum StirCtrl1Mask {
+	CTRL1_SDMODE = 0x80,
+	CTRL1_RXSLOW = 0x40,
+	CTRL1_TXPWD = 0x10,
+	CTRL1_RXPWD = 0x08,
+	CTRL1_SRESET = 0x01,
+};
+
+enum StirCtrl2Mask {
+	CTRL2_SPWIDTH = 0x08,
+	CTRL2_REVID = 0x03,
+};
+
+enum StirFifoCtlMask {
+	FIFOCTL_DIR = 0x10,
+	FIFOCTL_CLR = 0x08,
+	FIFOCTL_EMPTY = 0x04,
+};
+
+enum StirDiagMask {
+	IRDIG_RXHIGH = 0x80,
+	IRDIG_RXLOW = 0x40,
+};
+
+enum StirTestMask {
+	TEST_PLLDOWN = 0x80,
+	TEST_LOOPIR = 0x40,
+	TEST_LOOPUSB = 0x20,
+	TEST_TSTENA = 0x10,
+	TEST_TSTOSC = 0x0F,
+};
+
+struct stir_cb {
+        struct usb_device *usbdev;      /* init: probe_irda */
+        struct net_device *netdev;      /* network layer */
+        struct irlap_cb   *irlap;       /* The link layer we are binded to */
+
+        struct qos_info   qos;
+	unsigned 	  speed;	/* Current speed */
+
+        struct task_struct *thread;     /* transmit thread */
+
+	struct sk_buff	  *tx_pending;
+	void		  *io_buf;	/* transmit/receive buffer */
+	__u8		  *fifo_status;
+
+	iobuff_t  	  rx_buff;	/* receive unwrap state machine */
+	ktime_t		rx_time;
+	int		  receiving;
+	struct urb	 *rx_urb;
+};
+
+
+/* These are the currently known USB ids */
+static struct usb_device_id dongles[] = {
+    /* SigmaTel, Inc,  STIr4200 IrDA/USB Bridge */
+    { USB_DEVICE(0x066f, 0x4200) },
+    { }
+};
+
+MODULE_DEVICE_TABLE(usb, dongles);
+
+/* Send control message to set dongle register */
+static int write_reg(struct stir_cb *stir, __u16 reg, __u8 value)
+{
+	struct usb_device *dev = stir->usbdev;
+
+	pr_debug("%s: write reg %d = 0x%x\n",
+		 stir->netdev->name, reg, value);
+	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
+			       REQ_WRITE_SINGLE,
+			       USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_DEVICE,
+			       value, reg, NULL, 0,
+			       CTRL_TIMEOUT);
+}
+
+/* Send control message to read multiple registers */
+static inline int read_reg(struct stir_cb *stir, __u16 reg,
+		    __u8 *data, __u16 count)
+{
+	struct usb_device *dev = stir->usbdev;
+
+	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
+			       REQ_READ_REG,
+			       USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+			       0, reg, data, count,
+			       CTRL_TIMEOUT);
+}
+
+static inline int isfir(u32 speed)
+{
+	return speed == 4000000;
+}
+
+/*
+ * Prepare a FIR IrDA frame for transmission to the USB dongle.  The
+ * FIR transmit frame is documented in the datasheet.  It consists of
+ * a two byte 0x55 0xAA sequence, two little-endian length bytes, a
+ * sequence of exactly 16 XBOF bytes of 0x7E, two BOF bytes of 0x7E,
+ * then the data escaped as follows:
+ *
+ *    0x7D -> 0x7D 0x5D
+ *    0x7E -> 0x7D 0x5E
+ *    0x7F -> 0x7D 0x5F
+ *
+ * Then, 4 bytes of little endian (stuffed) FCS follow, then two
+ * trailing EOF bytes of 0x7E.
+ */
+static inline __u8 *stuff_fir(__u8 *p, __u8 c)
+{
+	switch(c) {
+	case 0x7d:
+	case 0x7e:
+	case 0x7f:
+		*p++ = 0x7d;
+		c ^= IRDA_TRANS;
+		/* fall through */
+	default:
+		*p++ = c;
+	}
+	return p;
+}
+
+/* Take raw data in skb and put it wrapped into buf */
+static unsigned wrap_fir_skb(const struct sk_buff *skb, __u8 *buf)
+{
+	__u8 *ptr = buf;
+	__u32 fcs = ~(crc32_le(~0, skb->data, skb->len));
+	__u16 wraplen;
+	int i;
+
+	/* Header */
+	buf[0] = 0x55;
+	buf[1] = 0xAA;
+
+	ptr = buf + STIR_IRDA_HEADER;
+	memset(ptr, 0x7f, 16);
+	ptr += 16;
+
+	/* BOF */
+	*ptr++  = 0x7e;
+	*ptr++  = 0x7e;
+
+	/* Address / Control / Information */
+	for (i = 0; i < skb->len; i++)
+		ptr = stuff_fir(ptr, skb->data[i]);
+
+	/* FCS */
+	ptr = stuff_fir(ptr, fcs & 0xff);
+	ptr = stuff_fir(ptr, (fcs >> 8) & 0xff);
+	ptr = stuff_fir(ptr, (fcs >> 16) & 0xff);
+	ptr = stuff_fir(ptr, (fcs >> 24) & 0xff);
+
+	/* EOFs */
+	*ptr++ = 0x7e;
+	*ptr++ = 0x7e;
+
+	/* Total length, minus the header */
+	wraplen = (ptr - buf) - STIR_IRDA_HEADER;
+	buf[2] = wraplen & 0xff;
+	buf[3] = (wraplen >> 8) & 0xff;
+
+	return wraplen + STIR_IRDA_HEADER;
+}
+
+static unsigned wrap_sir_skb(struct sk_buff *skb, __u8 *buf)
+{
+	__u16 wraplen;
+
+	wraplen = async_wrap_skb(skb, buf + STIR_IRDA_HEADER,
+				 STIR_FIFO_SIZE - STIR_IRDA_HEADER);
+	buf[0] = 0x55;
+	buf[1] = 0xAA;
+	buf[2] = wraplen & 0xff;
+	buf[3] = (wraplen >> 8) & 0xff;
+
+	return wraplen + STIR_IRDA_HEADER;
+}
+
+/*
+ * Frame is fully formed in the rx_buff so check crc
+ * and pass up to irlap
+ * setup for next receive
+ */
+static void fir_eof(struct stir_cb *stir)
+{
+	iobuff_t *rx_buff = &stir->rx_buff;
+	int len = rx_buff->len - 4;
+	struct sk_buff *skb, *nskb;
+	__u32 fcs;
+
+	if (unlikely(len <= 0)) {
+		pr_debug("%s: short frame len %d\n",
+			 stir->netdev->name, len);
+
+		++stir->netdev->stats.rx_errors;
+		++stir->netdev->stats.rx_length_errors;
+		return;
+	}
+
+	fcs = ~(crc32_le(~0, rx_buff->data, len));
+	if (fcs != get_unaligned_le32(rx_buff->data + len)) {
+		pr_debug("crc error calc 0x%x len %d\n", fcs, len);
+		stir->netdev->stats.rx_errors++;
+		stir->netdev->stats.rx_crc_errors++;
+		return;
+	}
+
+	/* if frame is short then just copy it */
+	if (len < IRDA_RX_COPY_THRESHOLD) {
+		nskb = dev_alloc_skb(len + 1);
+		if (unlikely(!nskb)) {
+			++stir->netdev->stats.rx_dropped;
+			return;
+		}
+		skb_reserve(nskb, 1);
+		skb = nskb;
+		skb_copy_to_linear_data(nskb, rx_buff->data, len);
+	} else {
+		nskb = dev_alloc_skb(rx_buff->truesize);
+		if (unlikely(!nskb)) {
+			++stir->netdev->stats.rx_dropped;
+			return;
+		}
+		skb_reserve(nskb, 1);
+		skb = rx_buff->skb;
+		rx_buff->skb = nskb;
+		rx_buff->head = nskb->data;
+	}
+
+	skb_put(skb, len);
+
+	skb_reset_mac_header(skb);
+	skb->protocol = htons(ETH_P_IRDA);
+	skb->dev = stir->netdev;
+
+	netif_rx(skb);
+
+	stir->netdev->stats.rx_packets++;
+	stir->netdev->stats.rx_bytes += len;
+
+	rx_buff->data = rx_buff->head;
+	rx_buff->len = 0;
+}
+
+/* Unwrap FIR stuffed data and bump it to IrLAP */
+static void stir_fir_chars(struct stir_cb *stir,
+			    const __u8 *bytes, int len)
+{
+	iobuff_t *rx_buff = &stir->rx_buff;
+	int	i;
+
+	for (i = 0; i < len; i++) {
+		__u8	byte = bytes[i];
+
+		switch(rx_buff->state) {
+		case OUTSIDE_FRAME:
+			/* ignore garbage till start of frame */
+			if (unlikely(byte != FIR_EOF))
+				continue;
+			/* Now receiving frame */
+			rx_buff->state = BEGIN_FRAME;
+
+			/* Time to initialize receive buffer */
+			rx_buff->data = rx_buff->head;
+			rx_buff->len = 0;
+			continue;
+
+		case LINK_ESCAPE:
+			if (byte == FIR_EOF) {
+				pr_debug("%s: got EOF after escape\n",
+					 stir->netdev->name);
+				goto frame_error;
+			}
+			rx_buff->state = INSIDE_FRAME;
+			byte ^= IRDA_TRANS;
+			break;
+
+		case BEGIN_FRAME:
+			/* ignore multiple BOF/EOF */
+			if (byte == FIR_EOF)
+				continue;
+			rx_buff->state = INSIDE_FRAME;
+			rx_buff->in_frame = TRUE;
+
+			/* fall through */
+		case INSIDE_FRAME:
+			switch(byte) {
+			case FIR_CE:
+				rx_buff->state = LINK_ESCAPE;
+				continue;
+			case FIR_XBOF:
+				/* 0x7f is not used in this framing */
+				pr_debug("%s: got XBOF without escape\n",
+					 stir->netdev->name);
+				goto frame_error;
+			case FIR_EOF:
+				rx_buff->state = OUTSIDE_FRAME;
+				rx_buff->in_frame = FALSE;
+				fir_eof(stir);
+				continue;
+			}
+			break;
+		}
+
+		/* add byte to rx buffer */
+		if (unlikely(rx_buff->len >= rx_buff->truesize)) {
+			pr_debug("%s: fir frame exceeds %d\n",
+				 stir->netdev->name, rx_buff->truesize);
+			++stir->netdev->stats.rx_over_errors;
+			goto error_recovery;
+		}
+
+		rx_buff->data[rx_buff->len++] = byte;
+		continue;
+
+	frame_error:
+		++stir->netdev->stats.rx_frame_errors;
+
+	error_recovery:
+		++stir->netdev->stats.rx_errors;
+		rx_buff->state = OUTSIDE_FRAME;
+		rx_buff->in_frame = FALSE;
+	}
+}
+
+/* Unwrap SIR stuffed data and bump it up to IrLAP */
+static void stir_sir_chars(struct stir_cb *stir,
+			    const __u8 *bytes, int len)
+{
+	int i;
+
+	for (i = 0; i < len; i++)
+		async_unwrap_char(stir->netdev, &stir->netdev->stats,
+				  &stir->rx_buff, bytes[i]);
+}
+
+static inline void unwrap_chars(struct stir_cb *stir,
+				const __u8 *bytes, int length)
+{
+	if (isfir(stir->speed))
+		stir_fir_chars(stir, bytes, length);
+	else
+		stir_sir_chars(stir, bytes, length);
+}
+
+/* Mode parameters for each speed */
+static const struct {
+	unsigned speed;
+	__u8 pdclk;
+} stir_modes[] = {
+        { 2400,    PDCLK_2400 },
+        { 9600,    PDCLK_9600 },
+        { 19200,   PDCLK_19200 },
+        { 38400,   PDCLK_38400 },
+        { 57600,   PDCLK_57600 },
+        { 115200,  PDCLK_115200 },
+        { 4000000, PDCLK_4000000 },
+};
+
+
+/*
+ * Setup chip for speed.
+ *  Called at startup to initialize the chip
+ *  and on speed changes.
+ *
+ * Note: Write multiple registers doesn't appear to work
+ */
+static int change_speed(struct stir_cb *stir, unsigned speed)
+{
+	int i, err;
+	__u8 mode;
+
+	for (i = 0; i < ARRAY_SIZE(stir_modes); ++i) {
+		if (speed == stir_modes[i].speed)
+			goto found;
+	}
+
+	dev_warn(&stir->netdev->dev, "invalid speed %d\n", speed);
+	return -EINVAL;
+
+ found:
+	pr_debug("speed change from %d to %d\n", stir->speed, speed);
+
+	/* Reset modulator */
+	err = write_reg(stir, REG_CTRL1, CTRL1_SRESET);
+	if (err)
+		goto out;
+
+	/* Undocumented magic to tweak the DPLL */
+	err = write_reg(stir, REG_DPLL, 0x15);
+	if (err)
+		goto out;
+
+	/* Set clock */
+	err = write_reg(stir, REG_PDCLK, stir_modes[i].pdclk);
+	if (err)
+		goto out;
+
+	mode = MODE_NRESET | MODE_FASTRX;
+	if (isfir(speed))
+		mode |= MODE_FIR | MODE_FFRSTEN;
+	else
+		mode |= MODE_SIR;
+
+	if (speed == 2400)
+		mode |= MODE_2400;
+
+	err = write_reg(stir, REG_MODE, mode);
+	if (err)
+		goto out;
+
+	/* This resets TEMIC style transceiver if any. */
+	err = write_reg(stir, REG_CTRL1,
+			CTRL1_SDMODE | (tx_power & 3) << 1);
+	if (err)
+		goto out;
+
+	err = write_reg(stir, REG_CTRL1, (tx_power & 3) << 1);
+	if (err)
+		goto out;
+
+	/* Reset sensitivity */
+	err = write_reg(stir, REG_CTRL2, (rx_sensitivity & 7) << 5);
+ out:
+	stir->speed = speed;
+	return err;
+}
+
+/*
+ * Called from net/core when new frame is available.
+ */
+static netdev_tx_t stir_hard_xmit(struct sk_buff *skb,
+					struct net_device *netdev)
+{
+	struct stir_cb *stir = netdev_priv(netdev);
+
+	netif_stop_queue(netdev);
+
+	/* the IRDA wrapping routines don't deal with non linear skb */
+	SKB_LINEAR_ASSERT(skb);
+
+	skb = xchg(&stir->tx_pending, skb);
+        wake_up_process(stir->thread);
+	
+	/* this should never happen unless stop/wakeup problem */
+	if (unlikely(skb)) {
+		WARN_ON(1);
+		dev_kfree_skb(skb);
+	}
+
+	return NETDEV_TX_OK;
+}
+
+/*
+ * Wait for the transmit FIFO to have space for next data
+ *
+ * If space < 0 then wait till FIFO completely drains.
+ * FYI: can take up to 13 seconds at 2400baud.
+ */
+static int fifo_txwait(struct stir_cb *stir, int space)
+{
+	int err;
+	unsigned long count, status;
+	unsigned long prev_count = 0x1fff;
+
+	/* Read FIFO status and count */
+	for (;; prev_count = count) {
+		err = read_reg(stir, REG_FIFOCTL, stir->fifo_status, 
+				   FIFO_REGS_SIZE);
+		if (unlikely(err != FIFO_REGS_SIZE)) {
+			dev_warn(&stir->netdev->dev,
+				 "FIFO register read error: %d\n", err);
+
+			return err;
+		}
+
+		status = stir->fifo_status[0];
+		count = (unsigned)(stir->fifo_status[2] & 0x1f) << 8 
+			| stir->fifo_status[1];
+
+		pr_debug("fifo status 0x%lx count %lu\n", status, count);
+
+		/* is fifo receiving already, or empty */
+		if (!(status & FIFOCTL_DIR) ||
+		    (status & FIFOCTL_EMPTY))
+			return 0;
+
+		if (signal_pending(current))
+			return -EINTR;
+
+		/* shutting down? */
+		if (!netif_running(stir->netdev) ||
+		    !netif_device_present(stir->netdev))
+			return -ESHUTDOWN;
+
+		/* only waiting for some space */
+		if (space >= 0 && STIR_FIFO_SIZE - 4 > space + count)
+			return 0;
+
+		/* queue confused */
+		if (prev_count < count)
+			break;
+
+		/* estimate transfer time for remaining chars */
+		msleep((count * 8000) / stir->speed);
+	}
+			
+	err = write_reg(stir, REG_FIFOCTL, FIFOCTL_CLR);
+	if (err) 
+		return err;
+	err = write_reg(stir, REG_FIFOCTL, 0);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+
+/* Wait for turnaround delay before starting transmit.  */
+static void turnaround_delay(const struct stir_cb *stir, long us)
+{
+	long ticks;
+
+	if (us <= 0)
+		return;
+
+	us -= ktime_us_delta(ktime_get(), stir->rx_time);
+
+	if (us < 10)
+		return;
+
+	ticks = us / (1000000 / HZ);
+	if (ticks > 0)
+		schedule_timeout_interruptible(1 + ticks);
+	else
+		udelay(us);
+}
+
+/*
+ * Start receiver by submitting a request to the receive pipe.
+ * If nothing is available it will return after rx_interval.
+ */
+static int receive_start(struct stir_cb *stir)
+{
+	/* reset state */
+	stir->receiving = 1;
+
+	stir->rx_buff.in_frame = FALSE;
+	stir->rx_buff.state = OUTSIDE_FRAME;
+
+	stir->rx_urb->status = 0;
+	return usb_submit_urb(stir->rx_urb, GFP_KERNEL);
+}
+
+/* Stop all pending receive Urb's */
+static void receive_stop(struct stir_cb *stir)
+{
+	stir->receiving = 0;
+	usb_kill_urb(stir->rx_urb);
+
+	if (stir->rx_buff.in_frame) 
+		stir->netdev->stats.collisions++;
+}
+/*
+ * Wrap data in socket buffer and send it.
+ */
+static void stir_send(struct stir_cb *stir, struct sk_buff *skb)
+{
+	unsigned wraplen;
+	int first_frame = 0;
+
+	/* if receiving, need to turnaround */
+	if (stir->receiving) {
+		receive_stop(stir);
+		turnaround_delay(stir, irda_get_mtt(skb));
+		first_frame = 1;
+	}
+
+	if (isfir(stir->speed))
+		wraplen = wrap_fir_skb(skb, stir->io_buf);
+	else
+		wraplen = wrap_sir_skb(skb, stir->io_buf);
+		
+	/* check for space available in fifo */
+	if (!first_frame)
+		fifo_txwait(stir, wraplen);
+
+	stir->netdev->stats.tx_packets++;
+	stir->netdev->stats.tx_bytes += skb->len;
+	stir->netdev->trans_start = jiffies;
+	pr_debug("send %d (%d)\n", skb->len, wraplen);
+
+	if (usb_bulk_msg(stir->usbdev, usb_sndbulkpipe(stir->usbdev, 1),
+			 stir->io_buf, wraplen,
+			 NULL, TRANSMIT_TIMEOUT))
+		stir->netdev->stats.tx_errors++;
+}
+
+/*
+ * Transmit state machine thread
+ */
+static int stir_transmit_thread(void *arg)
+{
+	struct stir_cb *stir = arg;
+	struct net_device *dev = stir->netdev;
+	struct sk_buff *skb;
+
+        while (!kthread_should_stop()) {
+#ifdef CONFIG_PM
+		/* if suspending, then power off and wait */
+		if (unlikely(freezing(current))) {
+			if (stir->receiving)
+				receive_stop(stir);
+			else
+				fifo_txwait(stir, -1);
+
+			write_reg(stir, REG_CTRL1, CTRL1_TXPWD|CTRL1_RXPWD);
+
+			try_to_freeze();
+
+			if (change_speed(stir, stir->speed))
+				break;
+		}
+#endif
+
+		/* if something to send? */
+		skb = xchg(&stir->tx_pending, NULL);
+		if (skb) {
+			unsigned new_speed = irda_get_next_speed(skb);
+			netif_wake_queue(dev);
+
+			if (skb->len > 0)
+				stir_send(stir, skb);
+			dev_kfree_skb(skb);
+
+			if ((new_speed != -1) && (stir->speed != new_speed)) {
+				if (fifo_txwait(stir, -1) ||
+				    change_speed(stir, new_speed))
+					break;
+			}
+			continue;
+		}
+
+		/* nothing to send? start receiving */
+		if (!stir->receiving &&
+		    irda_device_txqueue_empty(dev)) {
+			/* Wait otherwise chip gets confused. */
+			if (fifo_txwait(stir, -1))
+				break;
+
+			if (unlikely(receive_start(stir))) {
+				if (net_ratelimit())
+					dev_info(&dev->dev,
+						 "%s: receive usb submit failed\n",
+						 stir->netdev->name);
+				stir->receiving = 0;
+				msleep(10);
+				continue;
+			}
+		}
+
+		/* sleep if nothing to send */
+                set_current_state(TASK_INTERRUPTIBLE);
+                schedule();
+
+	}
+        return 0;
+}
+
+
+/*
+ * USB bulk receive completion callback.
+ * Wakes up every ms (usb round trip) with wrapped 
+ * data.
+ */
+static void stir_rcv_irq(struct urb *urb)
+{
+	struct stir_cb *stir = urb->context;
+	int err;
+
+	/* in process of stopping, just drop data */
+	if (!netif_running(stir->netdev))
+		return;
+
+	/* unlink, shutdown, unplug, other nasties */
+	if (urb->status != 0) 
+		return;
+
+	if (urb->actual_length > 0) {
+		pr_debug("receive %d\n", urb->actual_length);
+		unwrap_chars(stir, urb->transfer_buffer,
+			     urb->actual_length);
+
+		stir->rx_time = ktime_get();
+	}
+
+	/* kernel thread is stopping receiver don't resubmit */
+	if (!stir->receiving)
+		return;
+
+	/* resubmit existing urb */
+	err = usb_submit_urb(urb, GFP_ATOMIC);
+
+	/* in case of error, the kernel thread will restart us */
+	if (err) {
+		dev_warn(&stir->netdev->dev, "usb receive submit error: %d\n",
+			 err);
+		stir->receiving = 0;
+		wake_up_process(stir->thread);
+	}
+}
+
+/*
+ * Function stir_net_open (dev)
+ *
+ *    Network device is taken up. Usually this is done by "ifconfig irda0 up"
+ */
+static int stir_net_open(struct net_device *netdev)
+{
+	struct stir_cb *stir = netdev_priv(netdev);
+	int err;
+	char hwname[16];
+
+	err = usb_clear_halt(stir->usbdev, usb_sndbulkpipe(stir->usbdev, 1));
+	if (err)
+		goto err_out1;
+	err = usb_clear_halt(stir->usbdev, usb_rcvbulkpipe(stir->usbdev, 2));
+	if (err)
+		goto err_out1;
+
+	err = change_speed(stir, 9600);
+	if (err)
+		goto err_out1;
+
+	err = -ENOMEM;
+
+	/* Initialize for SIR/FIR to copy data directly into skb.  */
+	stir->receiving = 0;
+	stir->rx_buff.truesize = IRDA_SKB_MAX_MTU;
+	stir->rx_buff.skb = dev_alloc_skb(IRDA_SKB_MAX_MTU);
+	if (!stir->rx_buff.skb) 
+		goto err_out1;
+
+	skb_reserve(stir->rx_buff.skb, 1);
+	stir->rx_buff.head = stir->rx_buff.skb->data;
+	stir->rx_time = ktime_get();
+
+	stir->rx_urb = usb_alloc_urb(0, GFP_KERNEL);
+	if (!stir->rx_urb) 
+		goto err_out2;
+
+	stir->io_buf = kmalloc(STIR_FIFO_SIZE, GFP_KERNEL);
+	if (!stir->io_buf)
+		goto err_out3;
+
+	usb_fill_bulk_urb(stir->rx_urb, stir->usbdev,
+			  usb_rcvbulkpipe(stir->usbdev, 2),
+			  stir->io_buf, STIR_FIFO_SIZE,
+			  stir_rcv_irq, stir);
+
+	stir->fifo_status = kmalloc(FIFO_REGS_SIZE, GFP_KERNEL);
+	if (!stir->fifo_status) 
+		goto err_out4;
+		
+	/*
+	 * Now that everything should be initialized properly,
+	 * Open new IrLAP layer instance to take care of us...
+	 * Note : will send immediately a speed change...
+	 */
+	sprintf(hwname, "usb#%d", stir->usbdev->devnum);
+	stir->irlap = irlap_open(netdev, &stir->qos, hwname);
+	if (!stir->irlap) {
+		dev_err(&stir->usbdev->dev, "irlap_open failed\n");
+		goto err_out5;
+	}
+
+	/** Start kernel thread for transmit.  */
+	stir->thread = kthread_run(stir_transmit_thread, stir,
+				   "%s", stir->netdev->name);
+        if (IS_ERR(stir->thread)) {
+                err = PTR_ERR(stir->thread);
+		dev_err(&stir->usbdev->dev, "unable to start kernel thread\n");
+		goto err_out6;
+	}
+
+	netif_start_queue(netdev);
+
+	return 0;
+
+ err_out6:
+	irlap_close(stir->irlap);
+ err_out5:
+	kfree(stir->fifo_status);
+ err_out4:
+	kfree(stir->io_buf);
+ err_out3:
+	usb_free_urb(stir->rx_urb);
+ err_out2:
+	kfree_skb(stir->rx_buff.skb);
+ err_out1:
+	return err;
+}
+
+/*
+ * Function stir_net_close (stir)
+ *
+ *    Network device is taken down. Usually this is done by
+ *    "ifconfig irda0 down"
+ */
+static int stir_net_close(struct net_device *netdev)
+{
+	struct stir_cb *stir = netdev_priv(netdev);
+
+	/* Stop transmit processing */
+	netif_stop_queue(netdev);
+
+	/* Kill transmit thread */
+	kthread_stop(stir->thread);
+	kfree(stir->fifo_status);
+
+	/* Mop up receive urb's */
+	usb_kill_urb(stir->rx_urb);
+	
+	kfree(stir->io_buf);
+	usb_free_urb(stir->rx_urb);
+	kfree_skb(stir->rx_buff.skb);
+
+	/* Stop and remove instance of IrLAP */
+	if (stir->irlap)
+		irlap_close(stir->irlap);
+
+	stir->irlap = NULL;
+
+	return 0;
+}
+
+/*
+ * IOCTLs : Extra out-of-band network commands...
+ */
+static int stir_net_ioctl(struct net_device *netdev, struct ifreq *rq, int cmd)
+{
+	struct if_irda_req *irq = (struct if_irda_req *) rq;
+	struct stir_cb *stir = netdev_priv(netdev);
+	int ret = 0;
+
+	switch (cmd) {
+	case SIOCSBANDWIDTH: /* Set bandwidth */
+		if (!capable(CAP_NET_ADMIN))
+			return -EPERM;
+
+		/* Check if the device is still there */
+		if (netif_device_present(stir->netdev))
+			ret = change_speed(stir, irq->ifr_baudrate);
+		break;
+
+	case SIOCSMEDIABUSY: /* Set media busy */
+		if (!capable(CAP_NET_ADMIN))
+			return -EPERM;
+
+		/* Check if the IrDA stack is still there */
+		if (netif_running(stir->netdev))
+			irda_device_set_media_busy(stir->netdev, TRUE);
+		break;
+
+	case SIOCGRECEIVING:
+		/* Only approximately true */
+		irq->ifr_receiving = stir->receiving;
+		break;
+
+	default:
+		ret = -EOPNOTSUPP;
+	}
+
+	return ret;
+}
+
+static const struct net_device_ops stir_netdev_ops = {
+	.ndo_open       = stir_net_open,
+	.ndo_stop       = stir_net_close,
+	.ndo_start_xmit = stir_hard_xmit,
+	.ndo_do_ioctl   = stir_net_ioctl,
+};
+
+/*
+ * This routine is called by the USB subsystem for each new device
+ * in the system. We need to check if the device is ours, and in
+ * this case start handling it.
+ * Note : it might be worth protecting this function by a global
+ * spinlock... Or not, because maybe USB already deal with that...
+ */
+static int stir_probe(struct usb_interface *intf,
+		      const struct usb_device_id *id)
+{
+	struct usb_device *dev = interface_to_usbdev(intf);
+	struct stir_cb *stir = NULL;
+	struct net_device *net;
+	int ret = -ENOMEM;
+
+	/* Allocate network device container. */
+	net = alloc_irdadev(sizeof(*stir));
+	if(!net)
+		goto err_out1;
+
+	SET_NETDEV_DEV(net, &intf->dev);
+	stir = netdev_priv(net);
+	stir->netdev = net;
+	stir->usbdev = dev;
+
+	ret = usb_reset_configuration(dev);
+	if (ret != 0) {
+		dev_err(&intf->dev, "usb reset configuration failed\n");
+		goto err_out2;
+	}
+
+	printk(KERN_INFO "SigmaTel STIr4200 IRDA/USB found at address %d, "
+		"Vendor: %x, Product: %x\n",
+	       dev->devnum, le16_to_cpu(dev->descriptor.idVendor),
+	       le16_to_cpu(dev->descriptor.idProduct));
+
+	/* Initialize QoS for this device */
+	irda_init_max_qos_capabilies(&stir->qos);
+
+	/* That's the Rx capability. */
+	stir->qos.baud_rate.bits       &= IR_2400 | IR_9600 | IR_19200 |
+					 IR_38400 | IR_57600 | IR_115200 |
+					 (IR_4000000 << 8);
+	stir->qos.min_turn_time.bits   &= qos_mtt_bits;
+	irda_qos_bits_to_value(&stir->qos);
+
+	/* Override the network functions we need to use */
+	net->netdev_ops = &stir_netdev_ops;
+
+	ret = register_netdev(net);
+	if (ret != 0)
+		goto err_out2;
+
+	dev_info(&intf->dev, "IrDA: Registered SigmaTel device %s\n",
+		 net->name);
+
+	usb_set_intfdata(intf, stir);
+
+	return 0;
+
+err_out2:
+	free_netdev(net);
+err_out1:
+	return ret;
+}
+
+/*
+ * The current device is removed, the USB layer tell us to shut it down...
+ */
+static void stir_disconnect(struct usb_interface *intf)
+{
+	struct stir_cb *stir = usb_get_intfdata(intf);
+
+	if (!stir)
+		return;
+
+	unregister_netdev(stir->netdev);
+	free_netdev(stir->netdev);
+
+	usb_set_intfdata(intf, NULL);
+}
+
+#ifdef CONFIG_PM
+/* USB suspend, so power off the transmitter/receiver */
+static int stir_suspend(struct usb_interface *intf, pm_message_t message)
+{
+	struct stir_cb *stir = usb_get_intfdata(intf);
+
+	netif_device_detach(stir->netdev);
+	return 0;
+}
+
+/* Coming out of suspend, so reset hardware */
+static int stir_resume(struct usb_interface *intf)
+{
+	struct stir_cb *stir = usb_get_intfdata(intf);
+
+	netif_device_attach(stir->netdev);
+
+	/* receiver restarted when send thread wakes up */
+	return 0;
+}
+#endif
+
+/*
+ * USB device callbacks
+ */
+static struct usb_driver irda_driver = {
+	.name		= "stir4200",
+	.probe		= stir_probe,
+	.disconnect	= stir_disconnect,
+	.id_table	= dongles,
+#ifdef CONFIG_PM
+	.suspend	= stir_suspend,
+	.resume		= stir_resume,
+#endif
+};
+
+module_usb_driver(irda_driver);