/* $Id: cosa.c,v 1.31 2000/03/08 17:47:16 kas Exp $ */
  
  /*
   *  Copyright (C) 1995-1997  Jan "Yenya" Kasprzak <kas@fi.muni.cz>
   *  Generic HDLC port Copyright (C) 2008 Krzysztof Halasa <khc@pm.waw.pl>
   *
   *  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., 675 Mass Ave, Cambridge, MA 02139, USA.
   */
  
  /*
   * The driver for the SRP and COSA synchronous serial cards.
   *
   * HARDWARE INFO
   *
   * Both cards are developed at the Institute of Computer Science,
   * Masaryk University (http://www.ics.muni.cz/). The hardware is
   * developed by Jiri Novotny <novotny@ics.muni.cz>. More information
   * and the photo of both cards is available at
   * http://www.pavoucek.cz/cosa.html. The card documentation, firmwares
   * and other goods can be downloaded from ftp://ftp.ics.muni.cz/pub/cosa/.
   * For Linux-specific utilities, see below in the "Software info" section.
   * If you want to order the card, contact Jiri Novotny.
   *
   * The SRP (serial port?, the Czech word "srp" means "sickle") card
   * is a 2-port intelligent (with its own 8-bit CPU) synchronous serial card
   * with V.24 interfaces up to 80kb/s each.
   *
   * The COSA (communication serial adapter?, the Czech word "kosa" means
   * "scythe") is a next-generation sync/async board with two interfaces
   * - currently any of V.24, X.21, V.35 and V.36 can be selected.
   * It has a 16-bit SAB80166 CPU and can do up to 10 Mb/s per channel.
   * The 8-channels version is in development.
   *
   * Both types have downloadable firmware and communicate via ISA DMA.
   * COSA can be also a bus-mastering device.
   *
   * SOFTWARE INFO
   *
   * The homepage of the Linux driver is at http://www.fi.muni.cz/~kas/cosa/.
   * The CVS tree of Linux driver can be viewed there, as well as the
   * firmware binaries and user-space utilities for downloading the firmware
   * into the card and setting up the card.
   *
   * The Linux driver (unlike the present *BSD drivers :-) can work even
   * for the COSA and SRP in one computer and allows each channel to work
   * in one of the two modes (character or network device).
   *
   * AUTHOR
   *
   * The Linux driver was written by Jan "Yenya" Kasprzak <kas@fi.muni.cz>.
   *
   * You can mail me bugfixes and even success reports. I am especially
   * interested in the SMP and/or muliti-channel success/failure reports
   * (I wonder if I did the locking properly :-).
   *
   * THE AUTHOR USED THE FOLLOWING SOURCES WHEN PROGRAMMING THE DRIVER
   *
   * The COSA/SRP NetBSD driver by Zdenek Salvet and Ivos Cernohlavek
   * The skeleton.c by Donald Becker
   * The SDL Riscom/N2 driver by Mike Natale
   * The Comtrol Hostess SV11 driver by Alan Cox
   * The Sync PPP/Cisco HDLC layer (syncppp.c) ported to Linux by Alan Cox
   */
  
  #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  
  #include <linux/module.h>
  #include <linux/kernel.h>
  #include <linux/sched.h>
  #include <linux/slab.h>
  #include <linux/poll.h>
  #include <linux/fs.h>
  #include <linux/interrupt.h>
  #include <linux/delay.h>
  #include <linux/hdlc.h>
  #include <linux/errno.h>
  #include <linux/ioport.h>
  #include <linux/netdevice.h>
  #include <linux/spinlock.h>
  #include <linux/mutex.h>
  #include <linux/device.h>
  #include <asm/io.h>
  #include <asm/dma.h>
  #include <asm/byteorder.h>
  
  #undef COSA_SLOW_IO	/* for testing purposes only */
  
  #include "cosa.h"
  
  /* Maximum length of the identification string. */
  #define COSA_MAX_ID_STRING	128
  
  /* Maximum length of the channel name */
  #define COSA_MAX_NAME		(sizeof("cosaXXXcXXX")+1)
  
  /* Per-channel data structure */
  
  struct channel_data {
  	int usage;	/* Usage count; >0 for chrdev, -1 for netdev */
  	int num;	/* Number of the channel */
  	struct cosa_data *cosa;	/* Pointer to the per-card structure */
  	int txsize;	/* Size of transmitted data */
  	char *txbuf;	/* Transmit buffer */
  	char name[COSA_MAX_NAME];	/* channel name */
  
  	/* The HW layer interface */
  	/* routine called from the RX interrupt */
  	char *(*setup_rx)(struct channel_data *channel, int size);
  	/* routine called when the RX is done (from the EOT interrupt) */
  	int (*rx_done)(struct channel_data *channel);
  	/* routine called when the TX is done (from the EOT interrupt) */
  	int (*tx_done)(struct channel_data *channel, int size);
  
  	/* Character device parts */
  	struct mutex rlock;
  	struct semaphore wsem;
  	char *rxdata;
  	int rxsize;
  	wait_queue_head_t txwaitq, rxwaitq;
  	int tx_status, rx_status;
  
  	/* generic HDLC device parts */
  	struct net_device *netdev;
  	struct sk_buff *rx_skb, *tx_skb;
  };
  
  /* cosa->firmware_status bits */
  #define COSA_FW_RESET		(1<<0)	/* Is the ROM monitor active? */
  #define COSA_FW_DOWNLOAD	(1<<1)	/* Is the microcode downloaded? */
  #define COSA_FW_START		(1<<2)	/* Is the microcode running? */
  
  struct cosa_data {
  	int num;			/* Card number */
  	char name[COSA_MAX_NAME];	/* Card name - e.g "cosa0" */
  	unsigned int datareg, statusreg;	/* I/O ports */
  	unsigned short irq, dma;	/* IRQ and DMA number */
  	unsigned short startaddr;	/* Firmware start address */
  	unsigned short busmaster;	/* Use busmastering? */
  	int nchannels;			/* # of channels on this card */
  	int driver_status;		/* For communicating with firmware */
  	int firmware_status;		/* Downloaded, reseted, etc. */
  	unsigned long rxbitmap, txbitmap;/* Bitmap of channels who are willing to send/receive data */
  	unsigned long rxtx;		/* RX or TX in progress? */
  	int enabled;
  	int usage;				/* usage count */
  	int txchan, txsize, rxsize;
  	struct channel_data *rxchan;
  	char *bouncebuf;
  	char *txbuf, *rxbuf;
  	struct channel_data *chan;
  	spinlock_t lock;	/* For exclusive operations on this structure */
  	char id_string[COSA_MAX_ID_STRING];	/* ROM monitor ID string */
  	char *type;				/* card type */
  };
  
  /*
   * Define this if you want all the possible ports to be autoprobed.
   * It is here but it probably is not a good idea to use this.
   */
  /* #define COSA_ISA_AUTOPROBE	1 */
  
  /*
   * Character device major number. 117 was allocated for us.
   * The value of 0 means to allocate a first free one.
   */
  static DEFINE_MUTEX(cosa_chardev_mutex);
  static int cosa_major = 117;
  
  /*
   * Encoding of the minor numbers:
   * The lowest CARD_MINOR_BITS bits means the channel on the single card,
   * the highest bits means the card number.
   */
  #define CARD_MINOR_BITS	4	/* How many bits in minor number are reserved
  				 * for the single card */
  /*
   * The following depends on CARD_MINOR_BITS. Unfortunately, the "MODULE_STRING"
   * macro doesn't like anything other than the raw number as an argument :-(
   */
  #define MAX_CARDS	16
  /* #define MAX_CARDS	(1 << (8-CARD_MINOR_BITS)) */
  
  #define DRIVER_RX_READY		0x0001
  #define DRIVER_TX_READY		0x0002
  #define DRIVER_TXMAP_SHIFT	2
  #define DRIVER_TXMAP_MASK	0x0c	/* FIXME: 0xfc for 8-channel version */
  
  /*
   * for cosa->rxtx - indicates whether either transmit or receive is
   * in progress. These values are mean number of the bit.
   */
  #define TXBIT 0
  #define RXBIT 1
  #define IRQBIT 2
  
  #define COSA_MTU 2000	/* FIXME: I don't know this exactly */
  
  #undef DEBUG_DATA //1	/* Dump the data read or written to the channel */
  #undef DEBUG_IRQS //1	/* Print the message when the IRQ is received */
  #undef DEBUG_IO   //1	/* Dump the I/O traffic */
  
  #define TX_TIMEOUT	(5*HZ)
  
  /* Maybe the following should be allocated dynamically */
  static struct cosa_data cosa_cards[MAX_CARDS];
  static int nr_cards;
  
  #ifdef COSA_ISA_AUTOPROBE
  static int io[MAX_CARDS+1]  = { 0x220, 0x228, 0x210, 0x218, 0, };
  /* NOTE: DMA is not autoprobed!!! */
  static int dma[MAX_CARDS+1] = { 1, 7, 1, 7, 1, 7, 1, 7, 0, };
  #else
  static int io[MAX_CARDS+1];
  static int dma[MAX_CARDS+1];
  #endif
  /* IRQ can be safely autoprobed */
  static int irq[MAX_CARDS+1] = { -1, -1, -1, -1, -1, -1, 0, };
  
  /* for class stuff*/
  static struct class *cosa_class;
  
  #ifdef MODULE
  module_param_array(io, int, NULL, 0);
  MODULE_PARM_DESC(io, "The I/O bases of the COSA or SRP cards");
  module_param_array(irq, int, NULL, 0);
  MODULE_PARM_DESC(irq, "The IRQ lines of the COSA or SRP cards");
  module_param_array(dma, int, NULL, 0);
  MODULE_PARM_DESC(dma, "The DMA channels of the COSA or SRP cards");
  
  MODULE_AUTHOR("Jan \"Yenya\" Kasprzak, <kas@fi.muni.cz>");
  MODULE_DESCRIPTION("Modular driver for the COSA or SRP synchronous card");
  MODULE_LICENSE("GPL");
  #endif
  
  /* I use this mainly for testing purposes */
  #ifdef COSA_SLOW_IO
  #define cosa_outb outb_p
  #define cosa_outw outw_p
  #define cosa_inb  inb_p
  #define cosa_inw  inw_p
  #else
  #define cosa_outb outb
  #define cosa_outw outw
  #define cosa_inb  inb
  #define cosa_inw  inw
  #endif
  
  #define is_8bit(cosa)		(!(cosa->datareg & 0x08))
  
  #define cosa_getstatus(cosa)	(cosa_inb(cosa->statusreg))
  #define cosa_putstatus(cosa, stat)	(cosa_outb(stat, cosa->statusreg))
  #define cosa_getdata16(cosa)	(cosa_inw(cosa->datareg))
  #define cosa_getdata8(cosa)	(cosa_inb(cosa->datareg))
  #define cosa_putdata16(cosa, dt)	(cosa_outw(dt, cosa->datareg))
  #define cosa_putdata8(cosa, dt)	(cosa_outb(dt, cosa->datareg))
  
  /* Initialization stuff */
  static int cosa_probe(int ioaddr, int irq, int dma);
  
  /* HW interface */
  static void cosa_enable_rx(struct channel_data *chan);
  static void cosa_disable_rx(struct channel_data *chan);
  static int cosa_start_tx(struct channel_data *channel, char *buf, int size);
  static void cosa_kick(struct cosa_data *cosa);
  static int cosa_dma_able(struct channel_data *chan, char *buf, int data);
  
  /* Network device stuff */
  static int cosa_net_attach(struct net_device *dev, unsigned short encoding,
  			   unsigned short parity);
  static int cosa_net_open(struct net_device *d);
  static int cosa_net_close(struct net_device *d);
  static void cosa_net_timeout(struct net_device *d);
  static netdev_tx_t cosa_net_tx(struct sk_buff *skb, struct net_device *d);
  static char *cosa_net_setup_rx(struct channel_data *channel, int size);
  static int cosa_net_rx_done(struct channel_data *channel);
  static int cosa_net_tx_done(struct channel_data *channel, int size);
  static int cosa_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd);
  
  /* Character device */
  static char *chrdev_setup_rx(struct channel_data *channel, int size);
  static int chrdev_rx_done(struct channel_data *channel);
  static int chrdev_tx_done(struct channel_data *channel, int size);
  static ssize_t cosa_read(struct file *file,
  	char __user *buf, size_t count, loff_t *ppos);
  static ssize_t cosa_write(struct file *file,
  	const char __user *buf, size_t count, loff_t *ppos);
  static unsigned int cosa_poll(struct file *file, poll_table *poll);
  static int cosa_open(struct inode *inode, struct file *file);
  static int cosa_release(struct inode *inode, struct file *file);
  static long cosa_chardev_ioctl(struct file *file, unsigned int cmd,
  				unsigned long arg);
  #ifdef COSA_FASYNC_WORKING
  static int cosa_fasync(struct inode *inode, struct file *file, int on);
  #endif
  
  static const struct file_operations cosa_fops = {
  	.owner		= THIS_MODULE,
  	.llseek		= no_llseek,
  	.read		= cosa_read,
  	.write		= cosa_write,
  	.poll		= cosa_poll,
  	.unlocked_ioctl	= cosa_chardev_ioctl,
  	.open		= cosa_open,
  	.release	= cosa_release,
  #ifdef COSA_FASYNC_WORKING
  	.fasync		= cosa_fasync,
  #endif
  };
  
  /* Ioctls */
  static int cosa_start(struct cosa_data *cosa, int address);
  static int cosa_reset(struct cosa_data *cosa);
  static int cosa_download(struct cosa_data *cosa, void __user *a);
  static int cosa_readmem(struct cosa_data *cosa, void __user *a);
  
  /* COSA/SRP ROM monitor */
  static int download(struct cosa_data *cosa, const char __user *data, int addr, int len);
  static int startmicrocode(struct cosa_data *cosa, int address);
  static int readmem(struct cosa_data *cosa, char __user *data, int addr, int len);
  static int cosa_reset_and_read_id(struct cosa_data *cosa, char *id);
  
  /* Auxiliary functions */
  static int get_wait_data(struct cosa_data *cosa);
  static int put_wait_data(struct cosa_data *cosa, int data);
  static int puthexnumber(struct cosa_data *cosa, int number);
  static void put_driver_status(struct cosa_data *cosa);
  static void put_driver_status_nolock(struct cosa_data *cosa);
  
  /* Interrupt handling */
  static irqreturn_t cosa_interrupt(int irq, void *cosa);
  
  /* I/O ops debugging */
  #ifdef DEBUG_IO
  static void debug_data_in(struct cosa_data *cosa, int data);
  static void debug_data_out(struct cosa_data *cosa, int data);
  static void debug_data_cmd(struct cosa_data *cosa, int data);
  static void debug_status_in(struct cosa_data *cosa, int status);
  static void debug_status_out(struct cosa_data *cosa, int status);
  #endif
  
  static inline struct channel_data* dev_to_chan(struct net_device *dev)
  {
  	return (struct channel_data *)dev_to_hdlc(dev)->priv;
  }
  
  /* ---------- Initialization stuff ---------- */
  
  static int __init cosa_init(void)
  {
  	int i, err = 0;
  
  	if (cosa_major > 0) {
  		if (register_chrdev(cosa_major, "cosa", &cosa_fops)) {
  			pr_warn("unable to get major %d
  ", cosa_major);
  			err = -EIO;
  			goto out;
  		}
  	} else {
  		if (!(cosa_major=register_chrdev(0, "cosa", &cosa_fops))) {
  			pr_warn("unable to register chardev
  ");
  			err = -EIO;
  			goto out;
  		}
  	}
  	for (i=0; i<MAX_CARDS; i++)
  		cosa_cards[i].num = -1;
  	for (i=0; io[i] != 0 && i < MAX_CARDS; i++)
  		cosa_probe(io[i], irq[i], dma[i]);
  	if (!nr_cards) {
  		pr_warn("no devices found
  ");
  		unregister_chrdev(cosa_major, "cosa");
  		err = -ENODEV;
  		goto out;
  	}
  	cosa_class = class_create(THIS_MODULE, "cosa");
  	if (IS_ERR(cosa_class)) {
  		err = PTR_ERR(cosa_class);
  		goto out_chrdev;
  	}
  	for (i = 0; i < nr_cards; i++)
  		device_create(cosa_class, NULL, MKDEV(cosa_major, i), NULL,
  			      "cosa%d", i);
  	err = 0;
  	goto out;
  
  out_chrdev:
  	unregister_chrdev(cosa_major, "cosa");
  out:
  	return err;
  }
  module_init(cosa_init);
  
  static void __exit cosa_exit(void)
  {
  	struct cosa_data *cosa;
  	int i;
  
  	for (i = 0; i < nr_cards; i++)
  		device_destroy(cosa_class, MKDEV(cosa_major, i));
  	class_destroy(cosa_class);
  
  	for (cosa = cosa_cards; nr_cards--; cosa++) {
  		/* Clean up the per-channel data */
  		for (i = 0; i < cosa->nchannels; i++) {
  			/* Chardev driver has no alloc'd per-channel data */
  			unregister_hdlc_device(cosa->chan[i].netdev);
  			free_netdev(cosa->chan[i].netdev);
  		}
  		/* Clean up the per-card data */
  		kfree(cosa->chan);
  		kfree(cosa->bouncebuf);
  		free_irq(cosa->irq, cosa);
  		free_dma(cosa->dma);
  		release_region(cosa->datareg, is_8bit(cosa) ? 2 : 4);
  	}
  	unregister_chrdev(cosa_major, "cosa");
  }
  module_exit(cosa_exit);
  
  static const struct net_device_ops cosa_ops = {
  	.ndo_open       = cosa_net_open,
  	.ndo_stop       = cosa_net_close,
  	.ndo_change_mtu = hdlc_change_mtu,
  	.ndo_start_xmit = hdlc_start_xmit,
  	.ndo_do_ioctl   = cosa_net_ioctl,
  	.ndo_tx_timeout = cosa_net_timeout,
  };
  
  static int cosa_probe(int base, int irq, int dma)
  {
  	struct cosa_data *cosa = cosa_cards+nr_cards;
  	int i, err = 0;
  
  	memset(cosa, 0, sizeof(struct cosa_data));
  
  	/* Checking validity of parameters: */
  	/* IRQ should be 2-7 or 10-15; negative IRQ means autoprobe */
  	if ((irq >= 0  && irq < 2) || irq > 15 || (irq < 10 && irq > 7)) {
  		pr_info("invalid IRQ %d
  ", irq);
  		return -1;
  	}
  	/* I/O address should be between 0x100 and 0x3ff and should be
  	 * multiple of 8. */
  	if (base < 0x100 || base > 0x3ff || base & 0x7) {
  		pr_info("invalid I/O address 0x%x
  ", base);
  		return -1;
  	}
  	/* DMA should be 0,1 or 3-7 */
  	if (dma < 0 || dma == 4 || dma > 7) {
  		pr_info("invalid DMA %d
  ", dma);
  		return -1;
  	}
  	/* and finally, on 16-bit COSA DMA should be 4-7 and 
  	 * I/O base should not be multiple of 0x10 */
  	if (((base & 0x8) && dma < 4) || (!(base & 0x8) && dma > 3)) {
  		pr_info("8/16 bit base and DMA mismatch (base=0x%x, dma=%d)
  ",
  			base, dma);
  		return -1;
  	}
  
  	cosa->dma = dma;
  	cosa->datareg = base;
  	cosa->statusreg = is_8bit(cosa)?base+1:base+2;
  	spin_lock_init(&cosa->lock);
  
  	if (!request_region(base, is_8bit(cosa)?2:4,"cosa"))
  		return -1;
  	
  	if (cosa_reset_and_read_id(cosa, cosa->id_string) < 0) {
  		printk(KERN_DEBUG "probe at 0x%x failed.
  ", base);
  		err = -1;
  		goto err_out;
  	}
  
  	/* Test the validity of identification string */
  	if (!strncmp(cosa->id_string, "SRP", 3))
  		cosa->type = "srp";
  	else if (!strncmp(cosa->id_string, "COSA", 4))
  		cosa->type = is_8bit(cosa)? "cosa8": "cosa16";
  	else {
  /* Print a warning only if we are not autoprobing */
  #ifndef COSA_ISA_AUTOPROBE
  		pr_info("valid signature not found at 0x%x
  ", base);
  #endif
  		err = -1;
  		goto err_out;
  	}
  	/* Update the name of the region now we know the type of card */ 
  	release_region(base, is_8bit(cosa)?2:4);
  	if (!request_region(base, is_8bit(cosa)?2:4, cosa->type)) {
  		printk(KERN_DEBUG "changing name at 0x%x failed.
  ", base);
  		return -1;
  	}
  
  	/* Now do IRQ autoprobe */
  	if (irq < 0) {
  		unsigned long irqs;
  /*		pr_info("IRQ autoprobe
  "); */
  		irqs = probe_irq_on();
  		/* 
  		 * Enable interrupt on tx buffer empty (it sure is) 
  		 * really sure ?
  		 * FIXME: When this code is not used as module, we should
  		 * probably call udelay() instead of the interruptible sleep.
  		 */
  		set_current_state(TASK_INTERRUPTIBLE);
  		cosa_putstatus(cosa, SR_TX_INT_ENA);
  		schedule_timeout(30);
  		irq = probe_irq_off(irqs);
  		/* Disable all IRQs from the card */
  		cosa_putstatus(cosa, 0);
  		/* Empty the received data register */
  		cosa_getdata8(cosa);
  
  		if (irq < 0) {
  			pr_info("multiple interrupts obtained (%d, board at 0x%x)
  ",
  				irq, cosa->datareg);
  			err = -1;
  			goto err_out;
  		}
  		if (irq == 0) {
  			pr_info("no interrupt obtained (board at 0x%x)
  ",
  				cosa->datareg);
  		/*	return -1; */
  		}
  	}
  
  	cosa->irq = irq;
  	cosa->num = nr_cards;
  	cosa->usage = 0;
  	cosa->nchannels = 2;	/* FIXME: how to determine this? */
  
  	if (request_irq(cosa->irq, cosa_interrupt, 0, cosa->type, cosa)) {
  		err = -1;
  		goto err_out;
  	}
  	if (request_dma(cosa->dma, cosa->type)) {
  		err = -1;
  		goto err_out1;
  	}
  	
  	cosa->bouncebuf = kmalloc(COSA_MTU, GFP_KERNEL|GFP_DMA);
  	if (!cosa->bouncebuf) {
  		err = -ENOMEM;
  		goto err_out2;
  	}
  	sprintf(cosa->name, "cosa%d", cosa->num);
  
  	/* Initialize the per-channel data */
  	cosa->chan = kcalloc(cosa->nchannels, sizeof(struct channel_data), GFP_KERNEL);
  	if (!cosa->chan) {
  		err = -ENOMEM;
  		goto err_out3;
  	}
  
  	for (i = 0; i < cosa->nchannels; i++) {
  		struct channel_data *chan = &cosa->chan[i];
  
  		chan->cosa = cosa;
  		chan->num = i;
  		sprintf(chan->name, "cosa%dc%d", chan->cosa->num, i);
  
  		/* Initialize the chardev data structures */
  		mutex_init(&chan->rlock);
  		sema_init(&chan->wsem, 1);
  
  		/* Register the network interface */
  		if (!(chan->netdev = alloc_hdlcdev(chan))) {
  			pr_warn("%s: alloc_hdlcdev failed
  ", chan->name);
  			goto err_hdlcdev;
  		}
  		dev_to_hdlc(chan->netdev)->attach = cosa_net_attach;
  		dev_to_hdlc(chan->netdev)->xmit = cosa_net_tx;
  		chan->netdev->netdev_ops = &cosa_ops;
  		chan->netdev->watchdog_timeo = TX_TIMEOUT;
  		chan->netdev->base_addr = chan->cosa->datareg;
  		chan->netdev->irq = chan->cosa->irq;
  		chan->netdev->dma = chan->cosa->dma;
  		if (register_hdlc_device(chan->netdev)) {
  			netdev_warn(chan->netdev,
  				    "register_hdlc_device() failed
  ");
  			free_netdev(chan->netdev);
  			goto err_hdlcdev;
  		}
  	}
  
  	pr_info("cosa%d: %s (%s at 0x%x irq %d dma %d), %d channels
  ",
  		cosa->num, cosa->id_string, cosa->type,
  		cosa->datareg, cosa->irq, cosa->dma, cosa->nchannels);
  
  	return nr_cards++;
  
  err_hdlcdev:
  	while (i-- > 0) {
  		unregister_hdlc_device(cosa->chan[i].netdev);
  		free_netdev(cosa->chan[i].netdev);
  	}
  	kfree(cosa->chan);
  err_out3:
  	kfree(cosa->bouncebuf);
  err_out2:
  	free_dma(cosa->dma);
  err_out1:
  	free_irq(cosa->irq, cosa);
  err_out:
  	release_region(cosa->datareg,is_8bit(cosa)?2:4);
  	pr_notice("cosa%d: allocating resources failed
  ", cosa->num);
  	return err;
  }
  
  
  /*---------- network device ---------- */
  
  static int cosa_net_attach(struct net_device *dev, unsigned short encoding,
  			   unsigned short parity)
  {
  	if (encoding == ENCODING_NRZ && parity == PARITY_CRC16_PR1_CCITT)
  		return 0;
  	return -EINVAL;
  }
  
  static int cosa_net_open(struct net_device *dev)
  {
  	struct channel_data *chan = dev_to_chan(dev);
  	int err;
  	unsigned long flags;
  
  	if (!(chan->cosa->firmware_status & COSA_FW_START)) {
  		pr_notice("%s: start the firmware first (status %d)
  ",
  			  chan->cosa->name, chan->cosa->firmware_status);
  		return -EPERM;
  	}
  	spin_lock_irqsave(&chan->cosa->lock, flags);
  	if (chan->usage != 0) {
  		pr_warn("%s: cosa_net_open called with usage count %d
  ",
  			chan->name, chan->usage);
  		spin_unlock_irqrestore(&chan->cosa->lock, flags);
  		return -EBUSY;
  	}
  	chan->setup_rx = cosa_net_setup_rx;
  	chan->tx_done = cosa_net_tx_done;
  	chan->rx_done = cosa_net_rx_done;
  	chan->usage = -1;
  	chan->cosa->usage++;
  	spin_unlock_irqrestore(&chan->cosa->lock, flags);
  
  	err = hdlc_open(dev);
  	if (err) {
  		spin_lock_irqsave(&chan->cosa->lock, flags);
  		chan->usage = 0;
  		chan->cosa->usage--;
  		spin_unlock_irqrestore(&chan->cosa->lock, flags);
  		return err;
  	}
  
  	netif_start_queue(dev);
  	cosa_enable_rx(chan);
  	return 0;
  }
  
  static netdev_tx_t cosa_net_tx(struct sk_buff *skb,
  				     struct net_device *dev)
  {
  	struct channel_data *chan = dev_to_chan(dev);
  
  	netif_stop_queue(dev);
  
  	chan->tx_skb = skb;
  	cosa_start_tx(chan, skb->data, skb->len);
  	return NETDEV_TX_OK;
  }
  
  static void cosa_net_timeout(struct net_device *dev)
  {
  	struct channel_data *chan = dev_to_chan(dev);
  
  	if (test_bit(RXBIT, &chan->cosa->rxtx)) {
  		chan->netdev->stats.rx_errors++;
  		chan->netdev->stats.rx_missed_errors++;
  	} else {
  		chan->netdev->stats.tx_errors++;
  		chan->netdev->stats.tx_aborted_errors++;
  	}
  	cosa_kick(chan->cosa);
  	if (chan->tx_skb) {
  		dev_kfree_skb(chan->tx_skb);
  		chan->tx_skb = NULL;
  	}
  	netif_wake_queue(dev);
  }
  
  static int cosa_net_close(struct net_device *dev)
  {
  	struct channel_data *chan = dev_to_chan(dev);
  	unsigned long flags;
  
  	netif_stop_queue(dev);
  	hdlc_close(dev);
  	cosa_disable_rx(chan);
  	spin_lock_irqsave(&chan->cosa->lock, flags);
  	if (chan->rx_skb) {
  		kfree_skb(chan->rx_skb);
  		chan->rx_skb = NULL;
  	}
  	if (chan->tx_skb) {
  		kfree_skb(chan->tx_skb);
  		chan->tx_skb = NULL;
  	}
  	chan->usage = 0;
  	chan->cosa->usage--;
  	spin_unlock_irqrestore(&chan->cosa->lock, flags);
  	return 0;
  }
  
  static char *cosa_net_setup_rx(struct channel_data *chan, int size)
  {
  	/*
  	 * We can safely fall back to non-dma-able memory, because we have
  	 * the cosa->bouncebuf pre-allocated.
  	 */
  	kfree_skb(chan->rx_skb);
  	chan->rx_skb = dev_alloc_skb(size);
  	if (chan->rx_skb == NULL) {
  		pr_notice("%s: Memory squeeze, dropping packet
  ", chan->name);
  		chan->netdev->stats.rx_dropped++;
  		return NULL;
  	}
  	chan->netdev->trans_start = jiffies;
  	return skb_put(chan->rx_skb, size);
  }
  
  static int cosa_net_rx_done(struct channel_data *chan)
  {
  	if (!chan->rx_skb) {
  		pr_warn("%s: rx_done with empty skb!
  ", chan->name);
  		chan->netdev->stats.rx_errors++;
  		chan->netdev->stats.rx_frame_errors++;
  		return 0;
  	}
  	chan->rx_skb->protocol = hdlc_type_trans(chan->rx_skb, chan->netdev);
  	chan->rx_skb->dev = chan->netdev;
  	skb_reset_mac_header(chan->rx_skb);
  	chan->netdev->stats.rx_packets++;
  	chan->netdev->stats.rx_bytes += chan->cosa->rxsize;
  	netif_rx(chan->rx_skb);
  	chan->rx_skb = NULL;
  	return 0;
  }
  
  /* ARGSUSED */
  static int cosa_net_tx_done(struct channel_data *chan, int size)
  {
  	if (!chan->tx_skb) {
  		pr_warn("%s: tx_done with empty skb!
  ", chan->name);
  		chan->netdev->stats.tx_errors++;
  		chan->netdev->stats.tx_aborted_errors++;
  		return 1;
  	}
  	dev_kfree_skb_irq(chan->tx_skb);
  	chan->tx_skb = NULL;
  	chan->netdev->stats.tx_packets++;
  	chan->netdev->stats.tx_bytes += size;
  	netif_wake_queue(chan->netdev);
  	return 1;
  }
  
  /*---------- Character device ---------- */
  
  static ssize_t cosa_read(struct file *file,
  	char __user *buf, size_t count, loff_t *ppos)
  {
  	DECLARE_WAITQUEUE(wait, current);
  	unsigned long flags;
  	struct channel_data *chan = file->private_data;
  	struct cosa_data *cosa = chan->cosa;
  	char *kbuf;
  
  	if (!(cosa->firmware_status & COSA_FW_START)) {
  		pr_notice("%s: start the firmware first (status %d)
  ",
  			  cosa->name, cosa->firmware_status);
  		return -EPERM;
  	}
  	if (mutex_lock_interruptible(&chan->rlock))
  		return -ERESTARTSYS;
  	
  	chan->rxdata = kmalloc(COSA_MTU, GFP_DMA|GFP_KERNEL);
  	if (chan->rxdata == NULL) {
  		mutex_unlock(&chan->rlock);
  		return -ENOMEM;
  	}
  
  	chan->rx_status = 0;
  	cosa_enable_rx(chan);
  	spin_lock_irqsave(&cosa->lock, flags);
  	add_wait_queue(&chan->rxwaitq, &wait);
  	while (!chan->rx_status) {
  		current->state = TASK_INTERRUPTIBLE;
  		spin_unlock_irqrestore(&cosa->lock, flags);
  		schedule();
  		spin_lock_irqsave(&cosa->lock, flags);
  		if (signal_pending(current) && chan->rx_status == 0) {
  			chan->rx_status = 1;
  			remove_wait_queue(&chan->rxwaitq, &wait);
  			current->state = TASK_RUNNING;
  			spin_unlock_irqrestore(&cosa->lock, flags);
  			mutex_unlock(&chan->rlock);
  			return -ERESTARTSYS;
  		}
  	}
  	remove_wait_queue(&chan->rxwaitq, &wait);
  	current->state = TASK_RUNNING;
  	kbuf = chan->rxdata;
  	count = chan->rxsize;
  	spin_unlock_irqrestore(&cosa->lock, flags);
  	mutex_unlock(&chan->rlock);
  
  	if (copy_to_user(buf, kbuf, count)) {
  		kfree(kbuf);
  		return -EFAULT;
  	}
  	kfree(kbuf);
  	return count;
  }
  
  static char *chrdev_setup_rx(struct channel_data *chan, int size)
  {
  	/* Expect size <= COSA_MTU */
  	chan->rxsize = size;
  	return chan->rxdata;
  }
  
  static int chrdev_rx_done(struct channel_data *chan)
  {
  	if (chan->rx_status) { /* Reader has died */
  		kfree(chan->rxdata);
  		up(&chan->wsem);
  	}
  	chan->rx_status = 1;
  	wake_up_interruptible(&chan->rxwaitq);
  	return 1;
  }
  
  
  static ssize_t cosa_write(struct file *file,
  	const char __user *buf, size_t count, loff_t *ppos)
  {
  	DECLARE_WAITQUEUE(wait, current);
  	struct channel_data *chan = file->private_data;
  	struct cosa_data *cosa = chan->cosa;
  	unsigned long flags;
  	char *kbuf;
  
  	if (!(cosa->firmware_status & COSA_FW_START)) {
  		pr_notice("%s: start the firmware first (status %d)
  ",
  			  cosa->name, cosa->firmware_status);
  		return -EPERM;
  	}
  	if (down_interruptible(&chan->wsem))
  		return -ERESTARTSYS;
  
  	if (count > COSA_MTU)
  		count = COSA_MTU;
  	
  	/* Allocate the buffer */
  	kbuf = kmalloc(count, GFP_KERNEL|GFP_DMA);
  	if (kbuf == NULL) {
  		up(&chan->wsem);
  		return -ENOMEM;
  	}
  	if (copy_from_user(kbuf, buf, count)) {
  		up(&chan->wsem);
  		kfree(kbuf);
  		return -EFAULT;
  	}
  	chan->tx_status=0;
  	cosa_start_tx(chan, kbuf, count);
  
  	spin_lock_irqsave(&cosa->lock, flags);
  	add_wait_queue(&chan->txwaitq, &wait);
  	while (!chan->tx_status) {
  		current->state = TASK_INTERRUPTIBLE;
  		spin_unlock_irqrestore(&cosa->lock, flags);
  		schedule();
  		spin_lock_irqsave(&cosa->lock, flags);
  		if (signal_pending(current) && chan->tx_status == 0) {
  			chan->tx_status = 1;
  			remove_wait_queue(&chan->txwaitq, &wait);
  			current->state = TASK_RUNNING;
  			chan->tx_status = 1;
  			spin_unlock_irqrestore(&cosa->lock, flags);
  			up(&chan->wsem);
  			return -ERESTARTSYS;
  		}
  	}
  	remove_wait_queue(&chan->txwaitq, &wait);
  	current->state = TASK_RUNNING;
  	up(&chan->wsem);
  	spin_unlock_irqrestore(&cosa->lock, flags);
  	kfree(kbuf);
  	return count;
  }
  
  static int chrdev_tx_done(struct channel_data *chan, int size)
  {
  	if (chan->tx_status) { /* Writer was interrupted */
  		kfree(chan->txbuf);
  		up(&chan->wsem);
  	}
  	chan->tx_status = 1;
  	wake_up_interruptible(&chan->txwaitq);
  	return 1;
  }
  
  static unsigned int cosa_poll(struct file *file, poll_table *poll)
  {
  	pr_info("cosa_poll is here
  ");
  	return 0;
  }
  
  static int cosa_open(struct inode *inode, struct file *file)
  {
  	struct cosa_data *cosa;
  	struct channel_data *chan;
  	unsigned long flags;
  	int n;
  	int ret = 0;
  
  	mutex_lock(&cosa_chardev_mutex);
  	if ((n=iminor(file_inode(file))>>CARD_MINOR_BITS)
  		>= nr_cards) {
  		ret = -ENODEV;
  		goto out;
  	}
  	cosa = cosa_cards+n;
  
  	if ((n=iminor(file_inode(file))
  		& ((1<<CARD_MINOR_BITS)-1)) >= cosa->nchannels) {
  		ret = -ENODEV;
  		goto out;
  	}
  	chan = cosa->chan + n;
  	
  	file->private_data = chan;
  
  	spin_lock_irqsave(&cosa->lock, flags);
  
  	if (chan->usage < 0) { /* in netdev mode */
  		spin_unlock_irqrestore(&cosa->lock, flags);
  		ret = -EBUSY;
  		goto out;
  	}
  	cosa->usage++;
  	chan->usage++;
  
  	chan->tx_done = chrdev_tx_done;
  	chan->setup_rx = chrdev_setup_rx;
  	chan->rx_done = chrdev_rx_done;
  	spin_unlock_irqrestore(&cosa->lock, flags);
  out:
  	mutex_unlock(&cosa_chardev_mutex);
  	return ret;
  }
  
  static int cosa_release(struct inode *inode, struct file *file)
  {
  	struct channel_data *channel = file->private_data;
  	struct cosa_data *cosa;
  	unsigned long flags;
  
  	cosa = channel->cosa;
  	spin_lock_irqsave(&cosa->lock, flags);
  	cosa->usage--;
  	channel->usage--;
  	spin_unlock_irqrestore(&cosa->lock, flags);
  	return 0;
  }
  
  #ifdef COSA_FASYNC_WORKING
  static struct fasync_struct *fasync[256] = { NULL, };
  
  /* To be done ... */
  static int cosa_fasync(struct inode *inode, struct file *file, int on)
  {
          int port = iminor(inode);
  
  	return fasync_helper(inode, file, on, &fasync[port]);
  }
  #endif
  
  
  /* ---------- Ioctls ---------- */
  
  /*
   * Ioctl subroutines can safely be made inline, because they are called
   * only from cosa_ioctl().
   */
  static inline int cosa_reset(struct cosa_data *cosa)
  {
  	char idstring[COSA_MAX_ID_STRING];
  	if (cosa->usage > 1)
  		pr_info("cosa%d: WARNING: reset requested with cosa->usage > 1 (%d). Odd things may happen.
  ",
  			cosa->num, cosa->usage);
  	cosa->firmware_status &= ~(COSA_FW_RESET|COSA_FW_START);
  	if (cosa_reset_and_read_id(cosa, idstring) < 0) {
  		pr_notice("cosa%d: reset failed
  ", cosa->num);
  		return -EIO;
  	}
  	pr_info("cosa%d: resetting device: %s
  ", cosa->num, idstring);
  	cosa->firmware_status |= COSA_FW_RESET;
  	return 0;
  }
  
  /* High-level function to download data into COSA memory. Calls download() */
  static inline int cosa_download(struct cosa_data *cosa, void __user *arg)
  {
  	struct cosa_download d;
  	int i;
  
  	if (cosa->usage > 1)
  		pr_info("%s: WARNING: download of microcode requested with cosa->usage > 1 (%d). Odd things may happen.
  ",
  			cosa->name, cosa->usage);
  	if (!(cosa->firmware_status & COSA_FW_RESET)) {
  		pr_notice("%s: reset the card first (status %d)
  ",
  			  cosa->name, cosa->firmware_status);
  		return -EPERM;
  	}
  	
  	if (copy_from_user(&d, arg, sizeof(d)))
  		return -EFAULT;
  
  	if (d.addr < 0 || d.addr > COSA_MAX_FIRMWARE_SIZE)
  		return -EINVAL;
  	if (d.len < 0 || d.len > COSA_MAX_FIRMWARE_SIZE)
  		return -EINVAL;
  
  
  	/* If something fails, force the user to reset the card */
  	cosa->firmware_status &= ~(COSA_FW_RESET|COSA_FW_DOWNLOAD);
  
  	i = download(cosa, d.code, d.len, d.addr);
  	if (i < 0) {
  		pr_notice("cosa%d: microcode download failed: %d
  ",
  			  cosa->num, i);
  		return -EIO;
  	}
  	pr_info("cosa%d: downloading microcode - 0x%04x bytes at 0x%04x
  ",
  		cosa->num, d.len, d.addr);
  	cosa->firmware_status |= COSA_FW_RESET|COSA_FW_DOWNLOAD;
  	return 0;
  }
  
  /* High-level function to read COSA memory. Calls readmem() */
  static inline int cosa_readmem(struct cosa_data *cosa, void __user *arg)
  {
  	struct cosa_download d;
  	int i;
  
  	if (cosa->usage > 1)
  		pr_info("cosa%d: WARNING: readmem requested with cosa->usage > 1 (%d). Odd things may happen.
  ",
  			cosa->num, cosa->usage);
  	if (!(cosa->firmware_status & COSA_FW_RESET)) {
  		pr_notice("%s: reset the card first (status %d)
  ",
  			  cosa->name, cosa->firmware_status);
  		return -EPERM;
  	}
  
  	if (copy_from_user(&d, arg, sizeof(d)))
  		return -EFAULT;
  
  	/* If something fails, force the user to reset the card */
  	cosa->firmware_status &= ~COSA_FW_RESET;
  
  	i = readmem(cosa, d.code, d.len, d.addr);
  	if (i < 0) {
  		pr_notice("cosa%d: reading memory failed: %d
  ", cosa->num, i);
  		return -EIO;
  	}
  	pr_info("cosa%d: reading card memory - 0x%04x bytes at 0x%04x
  ",
  		cosa->num, d.len, d.addr);
  	cosa->firmware_status |= COSA_FW_RESET;
  	return 0;
  }
  
  /* High-level function to start microcode. Calls startmicrocode(). */
  static inline int cosa_start(struct cosa_data *cosa, int address)
  {
  	int i;
  
  	if (cosa->usage > 1)
  		pr_info("cosa%d: WARNING: start microcode requested with cosa->usage > 1 (%d). Odd things may happen.
  ",
  			cosa->num, cosa->usage);
  
  	if ((cosa->firmware_status & (COSA_FW_RESET|COSA_FW_DOWNLOAD))
  		!= (COSA_FW_RESET|COSA_FW_DOWNLOAD)) {
  		pr_notice("%s: download the microcode and/or reset the card first (status %d)
  ",
  			  cosa->name, cosa->firmware_status);
  		return -EPERM;
  	}
  	cosa->firmware_status &= ~COSA_FW_RESET;
  	if ((i=startmicrocode(cosa, address)) < 0) {
  		pr_notice("cosa%d: start microcode at 0x%04x failed: %d
  ",
  			  cosa->num, address, i);
  		return -EIO;
  	}
  	pr_info("cosa%d: starting microcode at 0x%04x
  ", cosa->num, address);
  	cosa->startaddr = address;
  	cosa->firmware_status |= COSA_FW_START;
  	return 0;
  }
  		
  /* Buffer of size at least COSA_MAX_ID_STRING is expected */
  static inline int cosa_getidstr(struct cosa_data *cosa, char __user *string)
  {
  	int l = strlen(cosa->id_string)+1;
  	if (copy_to_user(string, cosa->id_string, l))
  		return -EFAULT;
  	return l;
  }
  
  /* Buffer of size at least COSA_MAX_ID_STRING is expected */
  static inline int cosa_gettype(struct cosa_data *cosa, char __user *string)
  {
  	int l = strlen(cosa->type)+1;
  	if (copy_to_user(string, cosa->type, l))
  		return -EFAULT;
  	return l;
  }
  
  static int cosa_ioctl_common(struct cosa_data *cosa,
  	struct channel_data *channel, unsigned int cmd, unsigned long arg)
  {
  	void __user *argp = (void __user *)arg;
  	switch (cmd) {
  	case COSAIORSET:	/* Reset the device */
  		if (!capable(CAP_NET_ADMIN))
  			return -EACCES;
  		return cosa_reset(cosa);
  	case COSAIOSTRT:	/* Start the firmware */
  		if (!capable(CAP_SYS_RAWIO))
  			return -EACCES;
  		return cosa_start(cosa, arg);
  	case COSAIODOWNLD:	/* Download the firmware */
  		if (!capable(CAP_SYS_RAWIO))
  			return -EACCES;
  		
  		return cosa_download(cosa, argp);
  	case COSAIORMEM:
  		if (!capable(CAP_SYS_RAWIO))
  			return -EACCES;
  		return cosa_readmem(cosa, argp);
  	case COSAIORTYPE:
  		return cosa_gettype(cosa, argp);
  	case COSAIORIDSTR:
  		return cosa_getidstr(cosa, argp);
  	case COSAIONRCARDS:
  		return nr_cards;
  	case COSAIONRCHANS:
  		return cosa->nchannels;
  	case COSAIOBMSET:
  		if (!capable(CAP_SYS_RAWIO))
  			return -EACCES;
  		if (is_8bit(cosa))
  			return -EINVAL;
  		if (arg != COSA_BM_OFF && arg != COSA_BM_ON)
  			return -EINVAL;
  		cosa->busmaster = arg;
  		return 0;
  	case COSAIOBMGET:
  		return cosa->busmaster;
  	}
  	return -ENOIOCTLCMD;
  }
  
  static int cosa_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
  {
  	int rv;
  	struct channel_data *chan = dev_to_chan(dev);
  	rv = cosa_ioctl_common(chan->cosa, chan, cmd,
  			       (unsigned long)ifr->ifr_data);
  	if (rv != -ENOIOCTLCMD)
  		return rv;
  	return hdlc_ioctl(dev, ifr, cmd);
  }
  
  static long cosa_chardev_ioctl(struct file *file, unsigned int cmd,
  							unsigned long arg)
  {
  	struct channel_data *channel = file->private_data;
  	struct cosa_data *cosa;
  	long ret;
  
  	mutex_lock(&cosa_chardev_mutex);
  	cosa = channel->cosa;
  	ret = cosa_ioctl_common(cosa, channel, cmd, arg);
  	mutex_unlock(&cosa_chardev_mutex);
  	return ret;
  }
  
  
  /*---------- HW layer interface ---------- */
  
  /*
   * The higher layer can bind itself to the HW layer by setting the callbacks
   * in the channel_data structure and by using these routines.
   */
  static void cosa_enable_rx(struct channel_data *chan)
  {
  	struct cosa_data *cosa = chan->cosa;
  
  	if (!test_and_set_bit(chan->num, &cosa->rxbitmap))
  		put_driver_status(cosa);
  }
  
  static void cosa_disable_rx(struct channel_data *chan)
  {
  	struct cosa_data *cosa = chan->cosa;
  
  	if (test_and_clear_bit(chan->num, &cosa->rxbitmap))
  		put_driver_status(cosa);
  }
  
  /*
   * FIXME: This routine probably should check for cosa_start_tx() called when
   * the previous transmit is still unfinished. In this case the non-zero
   * return value should indicate to the caller that the queuing(sp?) up
   * the transmit has failed.
   */
  static int cosa_start_tx(struct channel_data *chan, char *buf, int len)
  {
  	struct cosa_data *cosa = chan->cosa;
  	unsigned long flags;
  #ifdef DEBUG_DATA
  	int i;
  
  	pr_info("cosa%dc%d: starting tx(0x%x)",
  		chan->cosa->num, chan->num, len);
  	for (i=0; i<len; i++)
  		pr_cont(" %02x", buf[i]&0xff);
  	pr_cont("
  ");
  #endif
  	spin_lock_irqsave(&cosa->lock, flags);
  	chan->txbuf = buf;
  	chan->txsize = len;
  	if (len > COSA_MTU)
  		chan->txsize = COSA_MTU;
  	spin_unlock_irqrestore(&cosa->lock, flags);
  
  	/* Tell the firmware we are ready */
  	set_bit(chan->num, &cosa->txbitmap);
  	put_driver_status(cosa);
  
  	return 0;
  }
  
  static void put_driver_status(struct cosa_data *cosa)
  {
  	unsigned long flags;
  	int status;
  
  	spin_lock_irqsave(&cosa->lock, flags);
  
  	status = (cosa->rxbitmap ? DRIVER_RX_READY : 0)
  		| (cosa->txbitmap ? DRIVER_TX_READY : 0)
  		| (cosa->txbitmap? ~(cosa->txbitmap<<DRIVER_TXMAP_SHIFT)
  			&DRIVER_TXMAP_MASK : 0);
  	if (!cosa->rxtx) {
  		if (cosa->rxbitmap|cosa->txbitmap) {
  			if (!cosa->enabled) {
  				cosa_putstatus(cosa, SR_RX_INT_ENA);
  #ifdef DEBUG_IO
  				debug_status_out(cosa, SR_RX_INT_ENA);
  #endif
  				cosa->enabled = 1;
  			}
  		} else if (cosa->enabled) {
  			cosa->enabled = 0;
  			cosa_putstatus(cosa, 0);
  #ifdef DEBUG_IO
  			debug_status_out(cosa, 0);
  #endif
  		}
  		cosa_putdata8(cosa, status);
  #ifdef DEBUG_IO
  		debug_data_cmd(cosa, status);
  #endif
  	}
  	spin_unlock_irqrestore(&cosa->lock, flags);
  }
  
  static void put_driver_status_nolock(struct cosa_data *cosa)
  {
  	int status;
  
  	status = (cosa->rxbitmap ? DRIVER_RX_READY : 0)
  		| (cosa->txbitmap ? DRIVER_TX_READY : 0)
  		| (cosa->txbitmap? ~(cosa->txbitmap<<DRIVER_TXMAP_SHIFT)
  			&DRIVER_TXMAP_MASK : 0);
  
  	if (cosa->rxbitmap|cosa->txbitmap) {
  		cosa_putstatus(cosa, SR_RX_INT_ENA);
  #ifdef DEBUG_IO
  		debug_status_out(cosa, SR_RX_INT_ENA);
  #endif
  		cosa->enabled = 1;
  	} else {
  		cosa_putstatus(cosa, 0);
  #ifdef DEBUG_IO
  		debug_status_out(cosa, 0);
  #endif
  		cosa->enabled = 0;
  	}
  	cosa_putdata8(cosa, status);
  #ifdef DEBUG_IO
  	debug_data_cmd(cosa, status);
  #endif
  }
  
  /*
   * The "kickme" function: When the DMA times out, this is called to
   * clean up the driver status.
   * FIXME: Preliminary support, the interface is probably wrong.
   */
  static void cosa_kick(struct cosa_data *cosa)
  {
  	unsigned long flags, flags1;
  	char *s = "(probably) IRQ";
  
  	if (test_bit(RXBIT, &cosa->rxtx))
  		s = "RX DMA";
  	if (test_bit(TXBIT, &cosa->rxtx))
  		s = "TX DMA";
  
  	pr_info("%s: %s timeout - restarting
  ", cosa->name, s);
  	spin_lock_irqsave(&cosa->lock, flags);
  	cosa->rxtx = 0;
  
  	flags1 = claim_dma_lock();
  	disable_dma(cosa->dma);
  	clear_dma_ff(cosa->dma);
  	release_dma_lock(flags1);
  
  	/* FIXME: Anything else? */
  	udelay(100);
  	cosa_putstatus(cosa, 0);
  	udelay(100);
  	(void) cosa_getdata8(cosa);
  	udelay(100);
  	cosa_putdata8(cosa, 0);
  	udelay(100);
  	put_driver_status_nolock(cosa);
  	spin_unlock_irqrestore(&cosa->lock, flags);
  }
  
  /*
   * Check if the whole buffer is DMA-able. It means it is below the 16M of
   * physical memory and doesn't span the 64k boundary. For now it seems
   * SKB's never do this, but we'll check this anyway.
   */
  static int cosa_dma_able(struct channel_data *chan, char *buf, int len)
  {
  	static int count;
  	unsigned long b = (unsigned long)buf;
  	if (b+len >= MAX_DMA_ADDRESS)
  		return 0;
  	if ((b^ (b+len)) & 0x10000) {
  		if (count++ < 5)
  			pr_info("%s: packet spanning a 64k boundary
  ",
  				chan->name);
  		return 0;
  	}
  	return 1;
  }
  
  
  /* ---------- The SRP/COSA ROM monitor functions ---------- */
  
  /*
   * Downloading SRP microcode: say "w" to SRP monitor, it answers by "w=",
   * drivers need to say 4-digit hex number meaning start address of the microcode
   * separated by a single space. Monitor replies by saying " =". Now driver
   * has to write 4-digit hex number meaning the last byte address ended
   * by a single space. Monitor has to reply with a space. Now the download
   * begins. After the download monitor replies with "\r
  ." (CR LF dot).
   */
  static int download(struct cosa_data *cosa, const char __user *microcode, int length, int address)
  {
  	int i;
  
  	if (put_wait_data(cosa, 'w') == -1) return -1;
  	if ((i=get_wait_data(cosa)) != 'w') { printk("dnld: 0x%04x
  ",i); return -2;}
  	if (get_wait_data(cosa) != '=') return -3;
  
  	if (puthexnumber(cosa, address) < 0) return -4;
  	if (put_wait_data(cosa, ' ') == -1) return -10;
  	if (get_wait_data(cosa) != ' ') return -11;
  	if (get_wait_data(cosa) != '=') return -12;
  
  	if (puthexnumber(cosa, address+length-1) < 0) return -13;
  	if (put_wait_data(cosa, ' ') == -1) return -18;
  	if (get_wait_data(cosa) != ' ') return -19;
  
  	while (length--) {
  		char c;
  #ifndef SRP_DOWNLOAD_AT_BOOT
  		if (get_user(c, microcode))
  			return -23; /* ??? */
  #else
  		c = *microcode;
  #endif
  		if (put_wait_data(cosa, c) == -1)
  			return -20;
  		microcode++;
  	}
  
  	if (get_wait_data(cosa) != '\r') return -21;
  	if (get_wait_data(cosa) != '
  ') return -22;
  	if (get_wait_data(cosa) != '.') return -23;
  #if 0
  	printk(KERN_DEBUG "cosa%d: download completed.
  ", cosa->num);
  #endif
  	return 0;
  }
  
  
  /*
   * Starting microcode is done via the "g" command of the SRP monitor.
   * The chat should be the following: "g" "g=" "<addr><CR>"
   * "<CR><CR><LF><CR><LF>".
   */
  static int startmicrocode(struct cosa_data *cosa, int address)
  {
  	if (put_wait_data(cosa, 'g') == -1) return -1;
  	if (get_wait_data(cosa) != 'g') return -2;
  	if (get_wait_data(cosa) != '=') return -3;
  
  	if (puthexnumber(cosa, address) < 0) return -4;
  	if (put_wait_data(cosa, '\r') == -1) return -5;
  	
  	if (get_wait_data(cosa) != '\r') return -6;
  	if (get_wait_data(cosa) != '\r') return -7;
  	if (get_wait_data(cosa) != '
  ') return -8;
  	if (get_wait_data(cosa) != '\r') return -9;
  	if (get_wait_data(cosa) != '
  ') return -10;
  #if 0
  	printk(KERN_DEBUG "cosa%d: microcode started
  ", cosa->num);
  #endif
  	return 0;
  }
  
  /*
   * Reading memory is done via the "r" command of the SRP monitor.
   * The chat is the following "r" "r=" "<addr> " " =" "<last_byte> " " "
   * Then driver can read the data and the conversation is finished
   * by SRP monitor sending "<CR><LF>." (dot at the end).
   *
   * This routine is not needed during the normal operation and serves
   * for debugging purposes only.
   */
  static int readmem(struct cosa_data *cosa, char __user *microcode, int length, int address)
  {
  	if (put_wait_data(cosa, 'r') == -1) return -1;
  	if ((get_wait_data(cosa)) != 'r') return -2;
  	if ((get_wait_data(cosa)) != '=') return -3;
  
  	if (puthexnumber(cosa, address) < 0) return -4;
  	if (put_wait_data(cosa, ' ') == -1) return -5;
  	if (get_wait_data(cosa) != ' ') return -6;
  	if (get_wait_data(cosa) != '=') return -7;
  
  	if (puthexnumber(cosa, address+length-1) < 0) return -8;
  	if (put_wait_data(cosa, ' ') == -1) return -9;
  	if (get_wait_data(cosa) != ' ') return -10;
  
  	while (length--) {
  		char c;
  		int i;
  		if ((i=get_wait_data(cosa)) == -1) {
  			pr_info("0x%04x bytes remaining
  ", length);
  			return -11;
  		}
  		c=i;
  #if 1
  		if (put_user(c, microcode))
  			return -23; /* ??? */
  #else
  		*microcode = c;
  #endif
  		microcode++;
  	}
  
  	if (get_wait_data(cosa) != '\r') return -21;
  	if (get_wait_data(cosa) != '
  ') return -22;
  	if (get_wait_data(cosa) != '.') return -23;
  #if 0
  	printk(KERN_DEBUG "cosa%d: readmem completed.
  ", cosa->num);
  #endif
  	return 0;
  }
  
  /*
   * This function resets the device and reads the initial prompt
   * of the device's ROM monitor.
   */
  static int cosa_reset_and_read_id(struct cosa_data *cosa, char *idstring)
  {
  	int i=0, id=0, prev=0, curr=0;
  
  	/* Reset the card ... */
  	cosa_putstatus(cosa, 0);
  	cosa_getdata8(cosa);
  	cosa_putstatus(cosa, SR_RST);
  #ifdef MODULE
  	msleep(500);
  #else
  	udelay(5*100000);
  #endif
  	/* Disable all IRQs from the card */
  	cosa_putstatus(cosa, 0);
  
  	/*
  	 * Try to read the ID string. The card then prints out the
  	 * identification string ended by the "
  \x2e".
  	 *
  	 * The following loop is indexed through i (instead of id)
  	 * to avoid looping forever when for any reason
  	 * the port returns '\r', '
  ' or '\x2e' permanently.
  	 */
  	for (i=0; i<COSA_MAX_ID_STRING-1; i++, prev=curr) {
  		if ((curr = get_wait_data(cosa)) == -1) {
  			return -1;
  		}
  		curr &= 0xff;
  		if (curr != '\r' && curr != '
  ' && curr != 0x2e)
  			idstring[id++] = curr;
  		if (curr == 0x2e && prev == '
  ')
  			break;
  	}
  	/* Perhaps we should fail when i==COSA_MAX_ID_STRING-1 ? */
  	idstring[id] = '\0';
  	return id;
  }
  
  
  /* ---------- Auxiliary routines for COSA/SRP monitor ---------- */
  
  /*
   * This routine gets the data byte from the card waiting for the SR_RX_RDY
   * bit to be set in a loop. It should be used in the exceptional cases
   * only (for example when resetting the card or downloading the firmware.
   */
  static int get_wait_data(struct cosa_data *cosa)
  {
  	int retries = 1000;
  
  	while (--retries) {
  		/* read data and return them */
  		if (cosa_getstatus(cosa) & SR_RX_RDY) {
  			short r;
  			r = cosa_getdata8(cosa);
  #if 0
  			pr_info("get_wait_data returning after %d retries
  ",
  				999-retries);
  #endif
  			return r;
  		}
  		/* sleep if not ready to read */
  		schedule_timeout_interruptible(1);
  	}
  	pr_info("timeout in get_wait_data (status 0x%x)
  ",
  		cosa_getstatus(cosa));
  	return -1;
  }
  
  /*
   * This routine puts the data byte to the card waiting for the SR_TX_RDY
   * bit to be set in a loop. It should be used in the exceptional cases
   * only (for example when resetting the card or downloading the firmware).
   */
  static int put_wait_data(struct cosa_data *cosa, int data)
  {
  	int retries = 1000;
  	while (--retries) {
  		/* read data and return them */
  		if (cosa_getstatus(cosa) & SR_TX_RDY) {
  			cosa_putdata8(cosa, data);
  #if 0
  			pr_info("Putdata: %d retries
  ", 999-retries);
  #endif
  			return 0;
  		}
  #if 0
  		/* sleep if not ready to read */
  		schedule_timeout_interruptible(1);
  #endif
  	}
  	pr_info("cosa%d: timeout in put_wait_data (status 0x%x)
  ",
  		cosa->num, cosa_getstatus(cosa));
  	return -1;
  }
  	
  /* 
   * The following routine puts the hexadecimal number into the SRP monitor
   * and verifies the proper echo of the sent bytes. Returns 0 on success,
   * negative number on failure (-1,-3,-5,-7) means that put_wait_data() failed,
   * (-2,-4,-6,-8) means that reading echo failed.
   */
  static int puthexnumber(struct cosa_data *cosa, int number)
  {
  	char temp[5];
  	int i;
  
  	/* Well, I should probably replace this by something faster. */
  	sprintf(temp, "%04X", number);
  	for (i=0; i<4; i++) {
  		if (put_wait_data(cosa, temp[i]) == -1) {
  			pr_notice("cosa%d: puthexnumber failed to write byte %d
  ",
  				  cosa->num, i);
  			return -1-2*i;
  		}
  		if (get_wait_data(cosa) != temp[i]) {
  			pr_notice("cosa%d: puthexhumber failed to read echo of byte %d
  ",
  				  cosa->num, i);
  			return -2-2*i;
  		}
  	}
  	return 0;
  }
  
  
  /* ---------- Interrupt routines ---------- */
  
  /*
   * There are three types of interrupt:
   * At the beginning of transmit - this handled is in tx_interrupt(),
   * at the beginning of receive - it is in rx_interrupt() and
   * at the end of transmit/receive - it is the eot_interrupt() function.
   * These functions are multiplexed by cosa_interrupt() according to the
   * COSA status byte. I have moved the rx/tx/eot interrupt handling into
   * separate functions to make it more readable. These functions are inline,
   * so there should be no overhead of function call.
   * 
   * In the COSA bus-master mode, we need to tell the card the address of a
   * buffer. Unfortunately, COSA may be too slow for us, so we must busy-wait.
   * It's time to use the bottom half :-(
   */
  
  /*
   * Transmit interrupt routine - called when COSA is willing to obtain
   * data from the OS. The most tricky part of the routine is selection
   * of channel we (OS) want to send packet for. For SRP we should probably
   * use the round-robin approach. The newer COSA firmwares have a simple
   * flow-control - in the status word has bits 2 and 3 set to 1 means that the
   * channel 0 or 1 doesn't want to receive data.
   *
   * It seems there is a bug in COSA firmware (need to trace it further):
   * When the driver status says that the kernel has no more data for transmit
   * (e.g. at the end of TX DMA) and then the kernel changes its mind
   * (e.g. new packet is queued to hard_start_xmit()), the card issues
   * the TX interrupt but does not mark the channel as ready-to-transmit.
   * The fix seems to be to push the packet to COSA despite its request.
   * We first try to obey the card's opinion, and then fall back to forced TX.
   */
  static inline void tx_interrupt(struct cosa_data *cosa, int status)
  {
  	unsigned long flags, flags1;
  #ifdef DEBUG_IRQS
  	pr_info("cosa%d: SR_DOWN_REQUEST status=0x%04x
  ", cosa->num, status);
  #endif
  	spin_lock_irqsave(&cosa->lock, flags);
  	set_bit(TXBIT, &cosa->rxtx);
  	if (!test_bit(IRQBIT, &cosa->rxtx)) {
  		/* flow control, see the comment above */
  		int i=0;
  		if (!cosa->txbitmap) {
  			pr_warn("%s: No channel wants data in TX IRQ. Expect DMA timeout.
  ",
  				cosa->name);
  			put_driver_status_nolock(cosa);
  			clear_bit(TXBIT, &cosa->rxtx);
  			spin_unlock_irqrestore(&cosa->lock, flags);
  			return;
  		}
  		while (1) {
  			cosa->txchan++;
  			i++;
  			if (cosa->txchan >= cosa->nchannels)
  				cosa->txchan = 0;
  			if (!(cosa->txbitmap & (1<<cosa->txchan)))
  				continue;
  			if (~status & (1 << (cosa->txchan+DRIVER_TXMAP_SHIFT)))
  				break;
  			/* in second pass, accept first ready-to-TX channel */
  			if (i > cosa->nchannels) {
  				/* Can be safely ignored */
  #ifdef DEBUG_IRQS
  				printk(KERN_DEBUG "%s: Forcing TX "
  					"to not-ready channel %d
  ",
  					cosa->name, cosa->txchan);
  #endif
  				break;
  			}
  		}
  
  		cosa->txsize = cosa->chan[cosa->txchan].txsize;
  		if (cosa_dma_able(cosa->chan+cosa->txchan,
  			cosa->chan[cosa->txchan].txbuf, cosa->txsize)) {
  			cosa->txbuf = cosa->chan[cosa->txchan].txbuf;
  		} else {
  			memcpy(cosa->bouncebuf, cosa->chan[cosa->txchan].txbuf,
  				cosa->txsize);
  			cosa->txbuf = cosa->bouncebuf;
  		}
  	}
  
  	if (is_8bit(cosa)) {
  		if (!test_bit(IRQBIT, &cosa->rxtx)) {
  			cosa_putstatus(cosa, SR_TX_INT_ENA);
  			cosa_putdata8(cosa, ((cosa->txchan << 5) & 0xe0)|
  				((cosa->txsize >> 8) & 0x1f));
  #ifdef DEBUG_IO
  			debug_status_out(cosa, SR_TX_INT_ENA);
  			debug_data_out(cosa, ((cosa->txchan << 5) & 0xe0)|
                                  ((cosa->txsize >> 8) & 0x1f));
  			debug_data_in(cosa, cosa_getdata8(cosa));
  #else
  			cosa_getdata8(cosa);
  #endif
  			set_bit(IRQBIT, &cosa->rxtx);
  			spin_unlock_irqrestore(&cosa->lock, flags);
  			return;
  		} else {
  			clear_bit(IRQBIT, &cosa->rxtx);
  			cosa_putstatus(cosa, 0);
  			cosa_putdata8(cosa, cosa->txsize&0xff);
  #ifdef DEBUG_IO
  			debug_status_out(cosa, 0);
  			debug_data_out(cosa, cosa->txsize&0xff);
  #endif
  		}
  	} else {
  		cosa_putstatus(cosa, SR_TX_INT_ENA);
  		cosa_putdata16(cosa, ((cosa->txchan<<13) & 0xe000)
  			| (cosa->txsize & 0x1fff));
  #ifdef DEBUG_IO
  		debug_status_out(cosa, SR_TX_INT_ENA);
  		debug_data_out(cosa, ((cosa->txchan<<13) & 0xe000)
                          | (cosa->txsize & 0x1fff));
  		debug_data_in(cosa, cosa_getdata8(cosa));
  		debug_status_out(cosa, 0);
  #else
  		cosa_getdata8(cosa);
  #endif
  		cosa_putstatus(cosa, 0);
  	}
  
  	if (cosa->busmaster) {
  		unsigned long addr = virt_to_bus(cosa->txbuf);
  		int count=0;
  		pr_info("busmaster IRQ
  ");
  		while (!(cosa_getstatus(cosa)&SR_TX_RDY)) {
  			count++;
  			udelay(10);
  			if (count > 1000) break;
  		}
  		pr_info("status %x
  ", cosa_getstatus(cosa));
  		pr_info("ready after %d loops
  ", count);
  		cosa_putdata16(cosa, (addr >> 16)&0xffff);
  
  		count = 0;
  		while (!(cosa_getstatus(cosa)&SR_TX_RDY)) {
  			count++;
  			if (count > 1000) break;
  			udelay(10);
  		}
  		pr_info("ready after %d loops
  ", count);
  		cosa_putdata16(cosa, addr &0xffff);
  		flags1 = claim_dma_lock();
  		set_dma_mode(cosa->dma, DMA_MODE_CASCADE);
  		enable_dma(cosa->dma);
  		release_dma_lock(flags1);
  	} else {
  		/* start the DMA */
  		flags1 = claim_dma_lock();
  		disable_dma(cosa->dma);
  		clear_dma_ff(cosa->dma);
  		set_dma_mode(cosa->dma, DMA_MODE_WRITE);
  		set_dma_addr(cosa->dma, virt_to_bus(cosa->txbuf));
  		set_dma_count(cosa->dma, cosa->txsize);
  		enable_dma(cosa->dma);
  		release_dma_lock(flags1);
  	}
  	cosa_putstatus(cosa, SR_TX_DMA_ENA|SR_USR_INT_ENA);
  #ifdef DEBUG_IO
  	debug_status_out(cosa, SR_TX_DMA_ENA|SR_USR_INT_ENA);
  #endif
  	spin_unlock_irqrestore(&cosa->lock, flags);
  }
  
  static inline void rx_interrupt(struct cosa_data *cosa, int status)
  {
  	unsigned long flags;
  #ifdef DEBUG_IRQS
  	pr_info("cosa%d: SR_UP_REQUEST
  ", cosa->num);
  #endif
  
  	spin_lock_irqsave(&cosa->lock, flags);
  	set_bit(RXBIT, &cosa->rxtx);
  
  	if (is_8bit(cosa)) {
  		if (!test_bit(IRQBIT, &cosa->rxtx)) {
  			set_bit(IRQBIT, &cosa->rxtx);
  			put_driver_status_nolock(cosa);
  			cosa->rxsize = cosa_getdata8(cosa) <<8;
  #ifdef DEBUG_IO
  			debug_data_in(cosa, cosa->rxsize >> 8);
  #endif
  			spin_unlock_irqrestore(&cosa->lock, flags);
  			return;
  		} else {
  			clear_bit(IRQBIT, &cosa->rxtx);
  			cosa->rxsize |= cosa_getdata8(cosa) & 0xff;
  #ifdef DEBUG_IO
  			debug_data_in(cosa, cosa->rxsize & 0xff);
  #endif
  #if 0
  			pr_info("cosa%d: receive rxsize = (0x%04x)
  ",
  				cosa->num, cosa->rxsize);
  #endif
  		}
  	} else {
  		cosa->rxsize = cosa_getdata16(cosa);
  #ifdef DEBUG_IO
  		debug_data_in(cosa, cosa->rxsize);
  #endif
  #if 0
  		pr_info("cosa%d: receive rxsize = (0x%04x)
  ",
  			cosa->num, cosa->rxsize);
  #endif
  	}
  	if (((cosa->rxsize & 0xe000) >> 13) >= cosa->nchannels) {
  		pr_warn("%s: rx for unknown channel (0x%04x)
  ",
  			cosa->name, cosa->rxsize);
  		spin_unlock_irqrestore(&cosa->lock, flags);
  		goto reject;
  	}
  	cosa->rxchan = cosa->chan + ((cosa->rxsize & 0xe000) >> 13);
  	cosa->rxsize &= 0x1fff;
  	spin_unlock_irqrestore(&cosa->lock, flags);
  
  	cosa->rxbuf = NULL;
  	if (cosa->rxchan->setup_rx)
  		cosa->rxbuf = cosa->rxchan->setup_rx(cosa->rxchan, cosa->rxsize);
  
  	if (!cosa->rxbuf) {
  reject:		/* Reject the packet */
  		pr_info("cosa%d: rejecting packet on channel %d
  ",
  			cosa->num, cosa->rxchan->num);
  		cosa->rxbuf = cosa->bouncebuf;
  	}
  
  	/* start the DMA */
  	flags = claim_dma_lock();
  	disable_dma(cosa->dma);
  	clear_dma_ff(cosa->dma);
  	set_dma_mode(cosa->dma, DMA_MODE_READ);
  	if (cosa_dma_able(cosa->rxchan, cosa->rxbuf, cosa->rxsize & 0x1fff)) {
  		set_dma_addr(cosa->dma, virt_to_bus(cosa->rxbuf));
  	} else {
  		set_dma_addr(cosa->dma, virt_to_bus(cosa->bouncebuf));
  	}
  	set_dma_count(cosa->dma, (cosa->rxsize&0x1fff));
  	enable_dma(cosa->dma);
  	release_dma_lock(flags);
  	spin_lock_irqsave(&cosa->lock, flags);
  	cosa_putstatus(cosa, SR_RX_DMA_ENA|SR_USR_INT_ENA);
  	if (!is_8bit(cosa) && (status & SR_TX_RDY))
  		cosa_putdata8(cosa, DRIVER_RX_READY);
  #ifdef DEBUG_IO
  	debug_status_out(cosa, SR_RX_DMA_ENA|SR_USR_INT_ENA);
  	if (!is_8bit(cosa) && (status & SR_TX_RDY))
  		debug_data_cmd(cosa, DRIVER_RX_READY);
  #endif
  	spin_unlock_irqrestore(&cosa->lock, flags);
  }
  
  static inline void eot_interrupt(struct cosa_data *cosa, int status)
  {
  	unsigned long flags, flags1;
  	spin_lock_irqsave(&cosa->lock, flags);
  	flags1 = claim_dma_lock();
  	disable_dma(cosa->dma);
  	clear_dma_ff(cosa->dma);
  	release_dma_lock(flags1);
  	if (test_bit(TXBIT, &cosa->rxtx)) {
  		struct channel_data *chan = cosa->chan+cosa->txchan;
  		if (chan->tx_done)
  			if (chan->tx_done(chan, cosa->txsize))
  				clear_bit(chan->num, &cosa->txbitmap);
  	} else if (test_bit(RXBIT, &cosa->rxtx)) {
  #ifdef DEBUG_DATA
  	{
  		int i;
  		pr_info("cosa%dc%d: done rx(0x%x)",
  			cosa->num, cosa->rxchan->num, cosa->rxsize);
  		for (i=0; i<cosa->rxsize; i++)
  			pr_cont(" %02x", cosa->rxbuf[i]&0xff);
  		pr_cont("
  ");
  	}
  #endif
  		/* Packet for unknown channel? */
  		if (cosa->rxbuf == cosa->bouncebuf)
  			goto out;
  		if (!cosa_dma_able(cosa->rxchan, cosa->rxbuf, cosa->rxsize))
  			memcpy(cosa->rxbuf, cosa->bouncebuf, cosa->rxsize);
  		if (cosa->rxchan->rx_done)
  			if (cosa->rxchan->rx_done(cosa->rxchan))
  				clear_bit(cosa->rxchan->num, &cosa->rxbitmap);
  	} else {
  		pr_notice("cosa%d: unexpected EOT interrupt
  ", cosa->num);
  	}
  	/*
  	 * Clear the RXBIT, TXBIT and IRQBIT (the latest should be
  	 * cleared anyway). We should do it as soon as possible
  	 * so that we can tell the COSA we are done and to give it a time
  	 * for recovery.
  	 */
  out:
  	cosa->rxtx = 0;
  	put_driver_status_nolock(cosa);
  	spin_unlock_irqrestore(&cosa->lock, flags);
  }
  
  static irqreturn_t cosa_interrupt(int irq, void *cosa_)
  {
  	unsigned status;
  	int count = 0;
  	struct cosa_data *cosa = cosa_;
  again:
  	status = cosa_getstatus(cosa);
  #ifdef DEBUG_IRQS
  	pr_info("cosa%d: got IRQ, status 0x%02x
  ", cosa->num, status & 0xff);
  #endif
  #ifdef DEBUG_IO
  	debug_status_in(cosa, status);
  #endif
  	switch (status & SR_CMD_FROM_SRP_MASK) {
  	case SR_DOWN_REQUEST:
  		tx_interrupt(cosa, status);
  		break;
  	case SR_UP_REQUEST:
  		rx_interrupt(cosa, status);
  		break;
  	case SR_END_OF_TRANSFER:
  		eot_interrupt(cosa, status);
  		break;
  	default:
  		/* We may be too fast for SRP. Try to wait a bit more. */
  		if (count++ < 100) {
  			udelay(100);
  			goto again;
  		}
  		pr_info("cosa%d: unknown status 0x%02x in IRQ after %d retries
  ",
  			cosa->num, status & 0xff, count);
  	}
  #ifdef DEBUG_IRQS
  	if (count)
  		pr_info("%s: %d-times got unknown status in IRQ
  ",
  			cosa->name, count);
  	else
  		pr_info("%s: returning from IRQ
  ", cosa->name);
  #endif
  	return IRQ_HANDLED;
  }
  
  
  /* ---------- I/O debugging routines ---------- */
  /*
   * These routines can be used to monitor COSA/SRP I/O and to printk()
   * the data being transferred on the data and status I/O port in a
   * readable way.
   */
  
  #ifdef DEBUG_IO
  static void debug_status_in(struct cosa_data *cosa, int status)
  {
  	char *s;
  	switch (status & SR_CMD_FROM_SRP_MASK) {
  	case SR_UP_REQUEST:
  		s = "RX_REQ";
  		break;
  	case SR_DOWN_REQUEST:
  		s = "TX_REQ";
  		break;
  	case SR_END_OF_TRANSFER:
  		s = "ET_REQ";
  		break;
  	default:
  		s = "NO_REQ";
  		break;
  	}
  	pr_info("%s: IO: status -> 0x%02x (%s%s%s%s)
  ",
  		cosa->name,
  		status,
  		status & SR_USR_RQ ? "USR_RQ|" : "",
  		status & SR_TX_RDY ? "TX_RDY|" : "",
  		status & SR_RX_RDY ? "RX_RDY|" : "",
  		s);
  }
  
  static void debug_status_out(struct cosa_data *cosa, int status)
  {
  	pr_info("%s: IO: status <- 0x%02x (%s%s%s%s%s%s)
  ",
  		cosa->name,
  		status,
  		status & SR_RX_DMA_ENA  ? "RXDMA|"  : "!rxdma|",
  		status & SR_TX_DMA_ENA  ? "TXDMA|"  : "!txdma|",
  		status & SR_RST         ? "RESET|"  : "",
  		status & SR_USR_INT_ENA ? "USRINT|" : "!usrint|",
  		status & SR_TX_INT_ENA  ? "TXINT|"  : "!txint|",
  		status & SR_RX_INT_ENA  ? "RXINT"   : "!rxint");
  }
  
  static void debug_data_in(struct cosa_data *cosa, int data)
  {
  	pr_info("%s: IO: data -> 0x%04x
  ", cosa->name, data);
  }
  
  static void debug_data_out(struct cosa_data *cosa, int data)
  {
  	pr_info("%s: IO: data <- 0x%04x
  ", cosa->name, data);
  }
  
  static void debug_data_cmd(struct cosa_data *cosa, int data)
  {
  	pr_info("%s: IO: data <- 0x%04x (%s|%s)
  ",
  		cosa->name, data,
  		data & SR_RDY_RCV ? "RX_RDY" : "!rx_rdy",
  		data & SR_RDY_SND ? "TX_RDY" : "!tx_rdy");
  }
  #endif
  
  /* EOF -- this file has not been truncated */