summaryrefslogblamecommitdiffstats
path: root/drivers/net/wan/cosa.c
blob: cd8f04afed8f2cb1e30edce9212a35b41e487e5c (plain) (tree)
1
2
3
4
5
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956



                                                                  
                                                                         



















































                                                                           
                                                         
















                                                                         
 

                         
                        


                       

                            
                       



                            
                        
                         
                           



                          

                                                       










                                                         















                                                                         

                              




                                           

                                       
                                        
















                                                                             

                                                                                                      










































































                                                                                
                                













































                                                                            





                                                                           
                                                                          



                                                                              

                      









                                                                     

                                                                   



                                                                       
                                                 




                                      
                                             


























                                                                                        
                                                       









                                                                 




                                                                      





                                                























                                                                                  
                                                       



                                          
                                      

                                                                           

                 
 










                                              
 
                                      
                                                                 
                                  

                                                     
                                                   
                                                       
                                                                            

                                                                     





                                                
                                                                     




                                              








                                               


























































































































                                                                                                                   
                                                                                       
                          
                              

                              



















                                                                          
                                                     









                                                                        






                                                                                 






                                                             





                                  
        






                                                                   
                                         
 

                                                                           
 


                                                                         

 
                                                
 
                                                     









                                                                                

                                                                               


                                                                 



                                           


                                                         
                             

                                                            
                                
                                    



                                                                 
                               



                             

                                                            
 
                                                     




                                                 
                            

 
                                                    
 
                                                     

                                                 

                                                       
                

                                                        








                                            
                                                 
 
                                                     

                            

                              









                                                    
                        




                                                         
                                                                   




                                                                          
                                



                                                                           
                                                 

                            
                                            


                                           
                                                      



                                                                    

                                                      

                         

                                                                             
                                           

                                                           

                               



                 
                                                                



                                                                    

                                                        



                                        


                                             


                 

                                           













                                                                                
                                                   



                                                                             
                                           
















                                                                      
                                                   







                                                   
                                   













































































































                                                                                
                    
 
                      
                                                                     



                              

                            
                                                   



                                                                 







                                                           

                             







                                                   


                        






















                                                                      

                                                             






























































































































































































                                                                                                                                    
                                                                             

               





                                                             

 

                                                                          

                                                          







                                                         

















































































































































































































































































































































































                                                                                                          
                                                  
























                                                                               
                                                  




















































































































































































































































































































































                                                                                                   
                                                       













































































































                                                                                           
/* $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
 */

#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 <linux/smp_lock.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 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);

/* Auxilliary 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)) {
			printk(KERN_WARNING "cosa: unable to get major %d\n",
				cosa_major);
			err = -EIO;
			goto out;
		}
	} else {
		if (!(cosa_major=register_chrdev(0, "cosa", &cosa_fops))) {
			printk(KERN_WARNING "cosa: unable to register chardev\n");
			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) {
		printk(KERN_WARNING "cosa: no devices found.\n");
		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)) {
		printk (KERN_INFO "cosa_probe: invalid IRQ %d\n", 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) {
		printk (KERN_INFO "cosa_probe: invalid I/O address 0x%x\n",
			base);
		return -1;
	}
	/* DMA should be 0,1 or 3-7 */
	if (dma < 0 || dma == 4 || dma > 7) {
		printk (KERN_INFO "cosa_probe: invalid DMA %d\n", 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)) {
		printk (KERN_INFO "cosa_probe: 8/16 bit base and DMA mismatch"
			" (base=0x%x, dma=%d)\n", 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 "cosa: probe at 0x%x failed.\n", 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
		printk(KERN_INFO "cosa: valid signature not found at 0x%x.\n",
			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 "cosa: changing name at 0x%x failed.\n", base);
		return -1;
	}

	/* Now do IRQ autoprobe */
	if (irq < 0) {
		unsigned long irqs;
/*		printk(KERN_INFO "IRQ autoprobe\n"); */
		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) {
			printk (KERN_INFO "cosa IRQ autoprobe: multiple interrupts obtained (%d, board at 0x%x)\n",
				irq, cosa->datareg);
			err = -1;
			goto err_out;
		}
		if (irq == 0) {
			printk (KERN_INFO "cosa IRQ autoprobe: no interrupt obtained (board at 0x%x)\n",
				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);
		init_MUTEX(&chan->wsem);

		/* Register the network interface */
		if (!(chan->netdev = alloc_hdlcdev(chan))) {
			printk(KERN_WARNING "%s: alloc_hdlcdev failed.\n",
			       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)) {
			printk(KERN_WARNING "%s: register_hdlc_device()"
			       " failed.\n", chan->netdev->name);
			free_netdev(chan->netdev);
			goto err_hdlcdev;
		}
	}

	printk (KERN_INFO "cosa%d: %s (%s at 0x%x irq %d dma %d), %d channels\n",
		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);
	printk(KERN_NOTICE "cosa%d: allocating resources failed\n",
	       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)) {
		printk(KERN_NOTICE "%s: start the firmware first (status %d)\n",
			chan->cosa->name, chan->cosa->firmware_status);
		return -EPERM;
	}
	spin_lock_irqsave(&chan->cosa->lock, flags);
	if (chan->usage != 0) {
		printk(KERN_WARNING "%s: cosa_net_open called with usage count"
		       " %d\n", 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) {
		printk(KERN_NOTICE "%s: Memory squeeze, dropping packet\n",
			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) {
		printk(KERN_WARNING "%s: rx_done with empty skb!\n",
			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) {
		printk(KERN_WARNING "%s: tx_done with empty skb!\n",
			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)) {
		printk(KERN_NOTICE "%s: start the firmware first (status %d)\n",
			cosa->name, cosa->firmware_status);
		return -EPERM;
	}
	if (mutex_lock_interruptible(&chan->rlock))
		return -ERESTARTSYS;
	
	if ((chan->rxdata = kmalloc(COSA_MTU, GFP_DMA|GFP_KERNEL)) == NULL) {
		printk(KERN_INFO "%s: cosa_read() - OOM\n", cosa->name);
		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)) {
		printk(KERN_NOTICE "%s: start the firmware first (status %d)\n",
			cosa->name, cosa->firmware_status);
		return -EPERM;
	}
	if (down_interruptible(&chan->wsem))
		return -ERESTARTSYS;

	if (count > COSA_MTU)
		count = COSA_MTU;
	
	/* Allocate the buffer */
	if ((kbuf = kmalloc(count, GFP_KERNEL|GFP_DMA)) == NULL) {
		printk(KERN_NOTICE "%s: cosa_write() OOM - dropping packet\n",
			cosa->name);
		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);
			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)
{
	printk(KERN_INFO "cosa_poll is here\n");
	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;

	lock_kernel();
	if ((n=iminor(file->f_path.dentry->d_inode)>>CARD_MINOR_BITS)
		>= nr_cards) {
		ret = -ENODEV;
		goto out;
	}
	cosa = cosa_cards+n;

	if ((n=iminor(file->f_path.dentry->d_inode)
		& ((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:
	unlock_kernel();
	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)
		printk(KERN_INFO "cosa%d: WARNING: reset requested with cosa->usage > 1 (%d). Odd things may happen.\n",
			cosa->num, cosa->usage);
	cosa->firmware_status &= ~(COSA_FW_RESET|COSA_FW_START);
	if (cosa_reset_and_read_id(cosa, idstring) < 0) {
		printk(KERN_NOTICE "cosa%d: reset failed\n", cosa->num);
		return -EIO;
	}
	printk(KERN_INFO "cosa%d: resetting device: %s\n", 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)
		printk(KERN_INFO "%s: WARNING: download of microcode requested with cosa->usage > 1 (%d). Odd things may happen.\n",
			cosa->name, cosa->usage);
	if (!(cosa->firmware_status & COSA_FW_RESET)) {
		printk(KERN_NOTICE "%s: reset the card first (status %d).\n",
			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) {
		printk(KERN_NOTICE "cosa%d: microcode download failed: %d\n",
			cosa->num, i);
		return -EIO;
	}
	printk(KERN_INFO "cosa%d: downloading microcode - 0x%04x bytes at 0x%04x\n",
		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)
		printk(KERN_INFO "cosa%d: WARNING: readmem requested with "
			"cosa->usage > 1 (%d). Odd things may happen.\n",
			cosa->num, cosa->usage);
	if (!(cosa->firmware_status & COSA_FW_RESET)) {
		printk(KERN_NOTICE "%s: reset the card first (status %d).\n",
			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) {
		printk(KERN_NOTICE "cosa%d: reading memory failed: %d\n",
			cosa->num, i);
		return -EIO;
	}
	printk(KERN_INFO "cosa%d: reading card memory - 0x%04x bytes at 0x%04x\n",
		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)
		printk(KERN_INFO "cosa%d: WARNING: start microcode requested with cosa->usage > 1 (%d). Odd things may happen.\n",
			cosa->num, cosa->usage);

	if ((cosa->firmware_status & (COSA_FW_RESET|COSA_FW_DOWNLOAD))
		!= (COSA_FW_RESET|COSA_FW_DOWNLOAD)) {
		printk(KERN_NOTICE "%s: download the microcode and/or reset the card first (status %d).\n",
			cosa->name, cosa->firmware_status);
		return -EPERM;
	}
	cosa->firmware_status &= ~COSA_FW_RESET;
	if ((i=startmicrocode(cosa, address)) < 0) {
		printk(KERN_NOTICE "cosa%d: start microcode at 0x%04x failed: %d\n",
			cosa->num, address, i);
		return -EIO;
	}
	printk(KERN_INFO "cosa%d: starting microcode at 0x%04x\n",
		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;

	lock_kernel();
	cosa = channel->cosa;
	ret = cosa_ioctl_common(cosa, channel, cmd, arg);
	unlock_kernel();
	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;

	printk(KERN_INFO "cosa%dc%d: starting tx(0x%x)", chan->cosa->num,
		chan->num, len);
	for (i=0; i<len; i++)
		printk(" %02x", buf[i]&0xff);
	printk("\n");
#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";

	printk(KERN_INFO "%s: %s timeout - restarting.\n", 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)
			printk(KERN_INFO "%s: packet spanning a 64k boundary\n",
				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\n." (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\n",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) != '\n') return -22;
	if (get_wait_data(cosa) != '.') return -23;
#if 0
	printk(KERN_DEBUG "cosa%d: download completed.\n", 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) != '\n') return -8;
	if (get_wait_data(cosa) != '\r') return -9;
	if (get_wait_data(cosa) != '\n') return -10;
#if 0
	printk(KERN_DEBUG "cosa%d: microcode started\n", 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) {
			printk (KERN_INFO "cosa: 0x%04x bytes remaining\n",
				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) != '\n') return -22;
	if (get_wait_data(cosa) != '.') return -23;
#if 0
	printk(KERN_DEBUG "cosa%d: readmem completed.\n", 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 "\n\x2e".
	 *
	 * The following loop is indexed through i (instead of id)
	 * to avoid looping forever when for any reason
	 * the port returns '\r', '\n' 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 != '\n' && curr != 0x2e)
			idstring[id++] = curr;
		if (curr == 0x2e && prev == '\n')
			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
			printk(KERN_INFO "cosa: get_wait_data returning after %d retries\n", 999-retries);
#endif
			return r;
		}
		/* sleep if not ready to read */
		schedule_timeout_interruptible(1);
	}
	printk(KERN_INFO "cosa: timeout in get_wait_data (status 0x%x)\n",
		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
			printk(KERN_INFO "Putdata: %d retries\n", 999-retries);
#endif
			return 0;
		}
#if 0
		/* sleep if not ready to read */
		schedule_timeout_interruptible(1);
#endif
	}
	printk(KERN_INFO "cosa%d: timeout in put_wait_data (status 0x%x)\n",
		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) {
			printk(KERN_NOTICE "cosa%d: puthexnumber failed to write byte %d\n",
				cosa->num, i);
			return -1-2*i;
		}
		if (get_wait_data(cosa) != temp[i]) {
			printk(KERN_NOTICE "cosa%d: puthexhumber failed to read echo of byte %d\n",
				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
	printk(KERN_INFO "cosa%d: SR_DOWN_REQUEST status=0x%04x\n",
		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) {
			printk(KERN_WARNING "%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\n",
					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;
		printk(KERN_INFO "busmaster IRQ\n");
		while (!(cosa_getstatus(cosa)&SR_TX_RDY)) {
			count++;
			udelay(10);
			if (count > 1000) break;
		}
		printk(KERN_INFO "status %x\n", cosa_getstatus(cosa));
		printk(KERN_INFO "ready after %d loops\n", count);
		cosa_putdata16(cosa, (addr >> 16)&0xffff);

		count = 0;
		while (!(cosa_getstatus(cosa)&SR_TX_RDY)) {
			count++;
			if (count > 1000) break;
			udelay(10);
		}
		printk(KERN_INFO "ready after %d loops\n", 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
	printk(KERN_INFO "cosa%d: SR_UP_REQUEST\n", 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
			printk(KERN_INFO "cosa%d: receive rxsize = (0x%04x).\n",
				cosa->num, cosa->rxsize);
#endif
		}
	} else {
		cosa->rxsize = cosa_getdata16(cosa);
#ifdef DEBUG_IO
		debug_data_in(cosa, cosa->rxsize);
#endif
#if 0
		printk(KERN_INFO "cosa%d: receive rxsize = (0x%04x).\n",
			cosa->num, cosa->rxsize);
#endif
	}
	if (((cosa->rxsize & 0xe000) >> 13) >= cosa->nchannels) {
		printk(KERN_WARNING "%s: rx for unknown channel (0x%04x)\n",
			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 */
		printk(KERN_INFO "cosa%d: rejecting packet on channel %d\n",
			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;
		printk(KERN_INFO "cosa%dc%d: done rx(0x%x)", cosa->num, 
			cosa->rxchan->num, cosa->rxsize);
		for (i=0; i<cosa->rxsize; i++)
			printk (" %02x", cosa->rxbuf[i]&0xff);
		printk("\n");
	}
#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 {
		printk(KERN_NOTICE "cosa%d: unexpected EOT interrupt\n",
			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
	printk(KERN_INFO "cosa%d: got IRQ, status 0x%02x\n", 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;
		}
		printk(KERN_INFO "cosa%d: unknown status 0x%02x in IRQ after %d retries\n",
			cosa->num, status & 0xff, count);
	}
#ifdef DEBUG_IRQS
	if (count)
		printk(KERN_INFO "%s: %d-times got unknown status in IRQ\n",
			cosa->name, count);
	else
		printk(KERN_INFO "%s: returning from IRQ\n", 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;
	}
	printk(KERN_INFO "%s: IO: status -> 0x%02x (%s%s%s%s)\n",
		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)
{
	printk(KERN_INFO "%s: IO: status <- 0x%02x (%s%s%s%s%s%s)\n",
		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)
{
	printk(KERN_INFO "%s: IO: data -> 0x%04x\n", cosa->name, data);
}

static void debug_data_out(struct cosa_data *cosa, int data)
{
	printk(KERN_INFO "%s: IO: data <- 0x%04x\n", cosa->name, data);
}

static void debug_data_cmd(struct cosa_data *cosa, int data)
{
	printk(KERN_INFO "%s: IO: data <- 0x%04x (%s|%s)\n",
		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 */