aboutsummaryrefslogblamecommitdiffstats
path: root/drivers/net/sb1000.c
blob: 66cf226c4ee32bd58091ba39c3882de16310d1d1 (plain) (tree)
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938



























































                                                                              
                                  




























                                                                                 


                                                                           
                                                                  




























































































































































                                                                              






















































                                                                                     
          



























































































































































                                                                                            
                  



























































                                                                               
                  




















































































































































































































































































































































































































                                                                                                                        
                  





























































































































































































































































                                                                                     
/* sb1000.c: A General Instruments SB1000 driver for linux. */
/*
	Written 1998 by Franco Venturi.

	Copyright 1998 by Franco Venturi.
	Copyright 1994,1995 by Donald Becker.
	Copyright 1993 United States Government as represented by the
	Director, National Security Agency.

	This driver is for the General Instruments SB1000 (internal SURFboard)

	The author may be reached as fventuri@mediaone.net

	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.

	Changes:

	981115 Steven Hirsch <shirsch@adelphia.net>

	Linus changed the timer interface.  Should work on all recent
	development kernels.

	980608 Steven Hirsch <shirsch@adelphia.net>

	Small changes to make it work with 2.1.x kernels. Hopefully,
	nothing major will change before official release of Linux 2.2.
	
	Merged with 2.2 - Alan Cox
*/

static char version[] = "sb1000.c:v1.1.2 6/01/98 (fventuri@mediaone.net)\n";

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/interrupt.h>
#include <linux/errno.h>
#include <linux/if_cablemodem.h> /* for SIOGCM/SIOSCM stuff */
#include <linux/in.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <linux/skbuff.h>
#include <linux/delay.h>	/* for udelay() */
#include <linux/etherdevice.h>
#include <linux/pnp.h>
#include <linux/init.h>
#include <linux/bitops.h>

#include <asm/io.h>
#include <asm/processor.h>
#include <asm/uaccess.h>

#ifdef SB1000_DEBUG
static int sb1000_debug = SB1000_DEBUG;
#else
static const int sb1000_debug = 1;
#endif

static const int SB1000_IO_EXTENT = 8;
/* SB1000 Maximum Receive Unit */
static const int SB1000_MRU = 1500; /* octects */

#define NPIDS 4
struct sb1000_private {
	struct sk_buff *rx_skb[NPIDS];
	short rx_dlen[NPIDS];
	unsigned int rx_frames;
	short rx_error_count;
	short rx_error_dpc_count;
	unsigned char rx_session_id[NPIDS];
	unsigned char rx_frame_id[NPIDS];
	unsigned char rx_pkt_type[NPIDS];
	struct net_device_stats stats;
};

/* prototypes for Linux interface */
extern int sb1000_probe(struct net_device *dev);
static int sb1000_open(struct net_device *dev);
static int sb1000_dev_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd);
static int sb1000_start_xmit(struct sk_buff *skb, struct net_device *dev);
static irqreturn_t sb1000_interrupt(int irq, void *dev_id, struct pt_regs *regs);
static struct net_device_stats *sb1000_stats(struct net_device *dev);
static int sb1000_close(struct net_device *dev);


/* SB1000 hardware routines to be used during open/configuration phases */
static inline int card_wait_for_busy_clear(const int ioaddr[],
	const char* name);
static inline int card_wait_for_ready(const int ioaddr[], const char* name,
	unsigned char in[]);
static int card_send_command(const int ioaddr[], const char* name,
	const unsigned char out[], unsigned char in[]);

/* SB1000 hardware routines to be used during frame rx interrupt */
static inline int sb1000_wait_for_ready(const int ioaddr[], const char* name);
static inline int sb1000_wait_for_ready_clear(const int ioaddr[],
	const char* name);
static inline void sb1000_send_command(const int ioaddr[], const char* name,
	const unsigned char out[]);
static inline void sb1000_read_status(const int ioaddr[], unsigned char in[]);
static inline void sb1000_issue_read_command(const int ioaddr[],
	const char* name);

/* SB1000 commands for open/configuration */
static inline int sb1000_reset(const int ioaddr[], const char* name);
static inline int sb1000_check_CRC(const int ioaddr[], const char* name);
static inline int sb1000_start_get_set_command(const int ioaddr[],
	const char* name);
static inline int sb1000_end_get_set_command(const int ioaddr[],
	const char* name);
static inline int sb1000_activate(const int ioaddr[], const char* name);
static int sb1000_get_firmware_version(const int ioaddr[],
	const char* name, unsigned char version[], int do_end);
static int sb1000_get_frequency(const int ioaddr[], const char* name,
	int* frequency);
static int sb1000_set_frequency(const int ioaddr[], const char* name,
	int frequency);
static int sb1000_get_PIDs(const int ioaddr[], const char* name,
	short PID[]);
static int sb1000_set_PIDs(const int ioaddr[], const char* name,
	const short PID[]);

/* SB1000 commands for frame rx interrupt */
static inline int sb1000_rx(struct net_device *dev);
static inline void sb1000_error_dpc(struct net_device *dev);

static const struct pnp_device_id sb1000_pnp_ids[] = {
	{ "GIC1000", 0 },
	{ "", 0 }
};
MODULE_DEVICE_TABLE(pnp, sb1000_pnp_ids);

static int
sb1000_probe_one(struct pnp_dev *pdev, const struct pnp_device_id *id)
{
	struct net_device *dev;
	unsigned short ioaddr[2], irq;
	unsigned int serial_number;
	int error = -ENODEV;
	
	if (pnp_device_attach(pdev) < 0)
		return -ENODEV;
	if (pnp_activate_dev(pdev) < 0)
		goto out_detach;

	if (!pnp_port_valid(pdev, 0) || !pnp_port_valid(pdev, 1))
		goto out_disable;
	if (!pnp_irq_valid(pdev, 0))
		goto out_disable;
		
	serial_number = pdev->card->serial;
		
	ioaddr[0] = pnp_port_start(pdev, 0);
	ioaddr[1] = pnp_port_start(pdev, 0);
		
	irq = pnp_irq(pdev, 0);

	if (!request_region(ioaddr[0], 16, "sb1000"))
		goto out_disable;
	if (!request_region(ioaddr[1], 16, "sb1000"))
		goto out_release_region0;

	dev = alloc_etherdev(sizeof(struct sb1000_private));
	if (!dev) {
		error = -ENOMEM;
		goto out_release_regions;
	}

		 
	dev->base_addr = ioaddr[0];
	/* mem_start holds the second I/O address */
	dev->mem_start = ioaddr[1];
	dev->irq = irq;

	if (sb1000_debug > 0)
		printk(KERN_NOTICE "%s: sb1000 at (%#3.3lx,%#3.3lx), "
			"S/N %#8.8x, IRQ %d.\n", dev->name, dev->base_addr,
			dev->mem_start, serial_number, dev->irq);

	/*
	 * The SB1000 is an rx-only cable modem device.  The uplink is a modem
	 * and we do not want to arp on it.
	 */
	dev->flags = IFF_POINTOPOINT|IFF_NOARP;

	SET_MODULE_OWNER(dev);
	SET_NETDEV_DEV(dev, &pdev->dev);

	if (sb1000_debug > 0)
		printk(KERN_NOTICE "%s", version);

	/* The SB1000-specific entries in the device structure. */
	dev->open		= sb1000_open;
	dev->do_ioctl		= sb1000_dev_ioctl;
	dev->hard_start_xmit	= sb1000_start_xmit;
	dev->stop		= sb1000_close;
	dev->get_stats		= sb1000_stats;

	/* hardware address is 0:0:serial_number */
	dev->dev_addr[2]	= serial_number >> 24 & 0xff;
	dev->dev_addr[3]	= serial_number >> 16 & 0xff;
	dev->dev_addr[4]	= serial_number >>  8 & 0xff;
	dev->dev_addr[5]	= serial_number >>  0 & 0xff;

	pnp_set_drvdata(pdev, dev);

	error = register_netdev(dev);
	if (error)
		goto out_free_netdev;
	return 0;

 out_free_netdev:
	free_netdev(dev);
 out_release_regions:
	release_region(ioaddr[1], 16);
 out_release_region0:
	release_region(ioaddr[0], 16);
 out_disable:
	pnp_disable_dev(pdev);
 out_detach:
	pnp_device_detach(pdev);
	return error;
}

static void
sb1000_remove_one(struct pnp_dev *pdev)
{
	struct net_device *dev = pnp_get_drvdata(pdev);

	unregister_netdev(dev);
	release_region(dev->base_addr, 16);
	release_region(dev->mem_start, 16);
	free_netdev(dev);
}

static struct pnp_driver sb1000_driver = {
	.name		= "sb1000",
	.id_table	= sb1000_pnp_ids,
	.probe		= sb1000_probe_one,
	.remove		= sb1000_remove_one,
};


/*
 * SB1000 hardware routines to be used during open/configuration phases
 */

static const int TimeOutJiffies = (875 * HZ) / 100;

/* Card Wait For Busy Clear (cannot be used during an interrupt) */
static inline int
card_wait_for_busy_clear(const int ioaddr[], const char* name)
{
	unsigned char a;
	unsigned long timeout;

	a = inb(ioaddr[0] + 7);
	timeout = jiffies + TimeOutJiffies;
	while (a & 0x80 || a & 0x40) {
		/* a little sleep */
		yield();

		a = inb(ioaddr[0] + 7);
		if (time_after_eq(jiffies, timeout)) {
			printk(KERN_WARNING "%s: card_wait_for_busy_clear timeout\n",
				name);
			return -ETIME;
		}
	}

	return 0;
}

/* Card Wait For Ready (cannot be used during an interrupt) */
static inline int
card_wait_for_ready(const int ioaddr[], const char* name, unsigned char in[])
{
	unsigned char a;
	unsigned long timeout;

	a = inb(ioaddr[1] + 6);
	timeout = jiffies + TimeOutJiffies;
	while (a & 0x80 || !(a & 0x40)) {
		/* a little sleep */
		yield();

		a = inb(ioaddr[1] + 6);
		if (time_after_eq(jiffies, timeout)) {
			printk(KERN_WARNING "%s: card_wait_for_ready timeout\n",
				name);
			return -ETIME;
		}
	}

	in[1] = inb(ioaddr[0] + 1);
	in[2] = inb(ioaddr[0] + 2);
	in[3] = inb(ioaddr[0] + 3);
	in[4] = inb(ioaddr[0] + 4);
	in[0] = inb(ioaddr[0] + 5);
	in[6] = inb(ioaddr[0] + 6);
	in[5] = inb(ioaddr[1] + 6);
	return 0;
}

/* Card Send Command (cannot be used during an interrupt) */
static int
card_send_command(const int ioaddr[], const char* name,
	const unsigned char out[], unsigned char in[])
{
	int status, x;

	if ((status = card_wait_for_busy_clear(ioaddr, name)))
		return status;
	outb(0xa0, ioaddr[0] + 6);
	outb(out[2], ioaddr[0] + 1);
	outb(out[3], ioaddr[0] + 2);
	outb(out[4], ioaddr[0] + 3);
	outb(out[5], ioaddr[0] + 4);
	outb(out[1], ioaddr[0] + 5);
	outb(0xa0, ioaddr[0] + 6);
	outb(out[0], ioaddr[0] + 7);
	if (out[0] != 0x20 && out[0] != 0x30) {
		if ((status = card_wait_for_ready(ioaddr, name, in)))
			return status;
		inb(ioaddr[0] + 7);
		if (sb1000_debug > 3)
			printk(KERN_DEBUG "%s: card_send_command "
				"out: %02x%02x%02x%02x%02x%02x  "
				"in: %02x%02x%02x%02x%02x%02x%02x\n", name,
				out[0], out[1], out[2], out[3], out[4], out[5],
				in[0], in[1], in[2], in[3], in[4], in[5], in[6]);
	} else {
		if (sb1000_debug > 3)
			printk(KERN_DEBUG "%s: card_send_command "
				"out: %02x%02x%02x%02x%02x%02x\n", name,
				out[0], out[1], out[2], out[3], out[4], out[5]);
	}

	if (out[1] == 0x1b) {
		x = (out[2] == 0x02);
	} else {
		if (out[0] >= 0x80 && in[0] != (out[1] | 0x80))
			return -EIO;
	}
	return 0;
}


/*
 * SB1000 hardware routines to be used during frame rx interrupt
 */
static const int Sb1000TimeOutJiffies = 7 * HZ;

/* Card Wait For Ready (to be used during frame rx) */
static inline int
sb1000_wait_for_ready(const int ioaddr[], const char* name)
{
	unsigned long timeout;

	timeout = jiffies + Sb1000TimeOutJiffies;
	while (inb(ioaddr[1] + 6) & 0x80) {
		if (time_after_eq(jiffies, timeout)) {
			printk(KERN_WARNING "%s: sb1000_wait_for_ready timeout\n",
				name);
			return -ETIME;
		}
	}
	timeout = jiffies + Sb1000TimeOutJiffies;
	while (!(inb(ioaddr[1] + 6) & 0x40)) {
		if (time_after_eq(jiffies, timeout)) {
			printk(KERN_WARNING "%s: sb1000_wait_for_ready timeout\n",
				name);
			return -ETIME;
		}
	}
	inb(ioaddr[0] + 7);
	return 0;
}

/* Card Wait For Ready Clear (to be used during frame rx) */
static inline int
sb1000_wait_for_ready_clear(const int ioaddr[], const char* name)
{
	unsigned long timeout;

	timeout = jiffies + Sb1000TimeOutJiffies;
	while (inb(ioaddr[1] + 6) & 0x80) {
		if (time_after_eq(jiffies, timeout)) {
			printk(KERN_WARNING "%s: sb1000_wait_for_ready_clear timeout\n",
				name);
			return -ETIME;
		}
	}
	timeout = jiffies + Sb1000TimeOutJiffies;
	while (inb(ioaddr[1] + 6) & 0x40) {
		if (time_after_eq(jiffies, timeout)) {
			printk(KERN_WARNING "%s: sb1000_wait_for_ready_clear timeout\n",
				name);
			return -ETIME;
		}
	}
	return 0;
}

/* Card Send Command (to be used during frame rx) */
static inline void
sb1000_send_command(const int ioaddr[], const char* name,
	const unsigned char out[])
{
	outb(out[2], ioaddr[0] + 1);
	outb(out[3], ioaddr[0] + 2);
	outb(out[4], ioaddr[0] + 3);
	outb(out[5], ioaddr[0] + 4);
	outb(out[1], ioaddr[0] + 5);
	outb(out[0], ioaddr[0] + 7);
	if (sb1000_debug > 3)
		printk(KERN_DEBUG "%s: sb1000_send_command out: %02x%02x%02x%02x"
			"%02x%02x\n", name, out[0], out[1], out[2], out[3], out[4], out[5]);
	return;
}

/* Card Read Status (to be used during frame rx) */
static inline void
sb1000_read_status(const int ioaddr[], unsigned char in[])
{
	in[1] = inb(ioaddr[0] + 1);
	in[2] = inb(ioaddr[0] + 2);
	in[3] = inb(ioaddr[0] + 3);
	in[4] = inb(ioaddr[0] + 4);
	in[0] = inb(ioaddr[0] + 5);
	return;
}

/* Issue Read Command (to be used during frame rx) */
static inline void
sb1000_issue_read_command(const int ioaddr[], const char* name)
{
	const unsigned char Command0[6] = {0x20, 0x00, 0x00, 0x01, 0x00, 0x00};

	sb1000_wait_for_ready_clear(ioaddr, name);
	outb(0xa0, ioaddr[0] + 6);
	sb1000_send_command(ioaddr, name, Command0);
	return;
}


/*
 * SB1000 commands for open/configuration
 */
/* reset SB1000 card */
static inline int
sb1000_reset(const int ioaddr[], const char* name)
{
	unsigned char st[7];
	int port, status;
	const unsigned char Command0[6] = {0x80, 0x16, 0x00, 0x00, 0x00, 0x00};

	port = ioaddr[1] + 6;
	outb(0x4, port);
	inb(port);
	udelay(1000);
	outb(0x0, port);
	inb(port);
	ssleep(1);
	outb(0x4, port);
	inb(port);
	udelay(1000);
	outb(0x0, port);
	inb(port);
	udelay(0);

	if ((status = card_send_command(ioaddr, name, Command0, st)))
		return status;
	if (st[3] != 0xf0)
		return -EIO;
	return 0;
}

/* check SB1000 firmware CRC */
static inline int
sb1000_check_CRC(const int ioaddr[], const char* name)
{
	unsigned char st[7];
	int crc, status;
	const unsigned char Command0[6] = {0x80, 0x1f, 0x00, 0x00, 0x00, 0x00};

	/* check CRC */
	if ((status = card_send_command(ioaddr, name, Command0, st)))
		return status;
	if (st[1] != st[3] || st[2] != st[4])
		return -EIO;
	crc = st[1] << 8 | st[2];
	return 0;
}

static inline int
sb1000_start_get_set_command(const int ioaddr[], const char* name)
{
	unsigned char st[7];
	const unsigned char Command0[6] = {0x80, 0x1b, 0x00, 0x00, 0x00, 0x00};

	return card_send_command(ioaddr, name, Command0, st);
}

static inline int
sb1000_end_get_set_command(const int ioaddr[], const char* name)
{
	unsigned char st[7];
	int status;
	const unsigned char Command0[6] = {0x80, 0x1b, 0x02, 0x00, 0x00, 0x00};
	const unsigned char Command1[6] = {0x20, 0x00, 0x00, 0x00, 0x00, 0x00};

	if ((status = card_send_command(ioaddr, name, Command0, st)))
		return status;
	return card_send_command(ioaddr, name, Command1, st);
}

static inline int
sb1000_activate(const int ioaddr[], const char* name)
{
	unsigned char st[7];
	int status;
	const unsigned char Command0[6] = {0x80, 0x11, 0x00, 0x00, 0x00, 0x00};
	const unsigned char Command1[6] = {0x80, 0x16, 0x00, 0x00, 0x00, 0x00};

	ssleep(1);
	if ((status = card_send_command(ioaddr, name, Command0, st)))
		return status;
	if ((status = card_send_command(ioaddr, name, Command1, st)))
		return status;
	if (st[3] != 0xf1) {
    	if ((status = sb1000_start_get_set_command(ioaddr, name)))
			return status;
		return -EIO;
	}
	udelay(1000);
    return sb1000_start_get_set_command(ioaddr, name);
}

/* get SB1000 firmware version */
static int
sb1000_get_firmware_version(const int ioaddr[], const char* name,
	unsigned char version[], int do_end)
{
	unsigned char st[7];
	int status;
	const unsigned char Command0[6] = {0x80, 0x23, 0x00, 0x00, 0x00, 0x00};

	if ((status = sb1000_start_get_set_command(ioaddr, name)))
		return status;
	if ((status = card_send_command(ioaddr, name, Command0, st)))
		return status;
	if (st[0] != 0xa3)
		return -EIO;
	version[0] = st[1];
	version[1] = st[2];
	if (do_end)
		return sb1000_end_get_set_command(ioaddr, name);
	else
		return 0;
}

/* get SB1000 frequency */
static int
sb1000_get_frequency(const int ioaddr[], const char* name, int* frequency)
{
	unsigned char st[7];
	int status;
	const unsigned char Command0[6] = {0x80, 0x44, 0x00, 0x00, 0x00, 0x00};

	udelay(1000);
	if ((status = sb1000_start_get_set_command(ioaddr, name)))
		return status;
	if ((status = card_send_command(ioaddr, name, Command0, st)))
		return status;
	*frequency = ((st[1] << 8 | st[2]) << 8 | st[3]) << 8 | st[4];
	return sb1000_end_get_set_command(ioaddr, name);
}

/* set SB1000 frequency */
static int
sb1000_set_frequency(const int ioaddr[], const char* name, int frequency)
{
	unsigned char st[7];
	int status;
	unsigned char Command0[6] = {0x80, 0x29, 0x00, 0x00, 0x00, 0x00};

	const int FrequencyLowerLimit = 57000;
	const int FrequencyUpperLimit = 804000;

	if (frequency < FrequencyLowerLimit || frequency > FrequencyUpperLimit) {
		printk(KERN_ERR "%s: frequency chosen (%d kHz) is not in the range "
			"[%d,%d] kHz\n", name, frequency, FrequencyLowerLimit,
			FrequencyUpperLimit);
		return -EINVAL;
	}
	udelay(1000);
	if ((status = sb1000_start_get_set_command(ioaddr, name)))
		return status;
	Command0[5] = frequency & 0xff;
	frequency >>= 8;
	Command0[4] = frequency & 0xff;
	frequency >>= 8;
	Command0[3] = frequency & 0xff;
	frequency >>= 8;
	Command0[2] = frequency & 0xff;
	return card_send_command(ioaddr, name, Command0, st);
}

/* get SB1000 PIDs */
static int
sb1000_get_PIDs(const int ioaddr[], const char* name, short PID[])
{
	unsigned char st[7];
	int status;
	const unsigned char Command0[6] = {0x80, 0x40, 0x00, 0x00, 0x00, 0x00};
	const unsigned char Command1[6] = {0x80, 0x41, 0x00, 0x00, 0x00, 0x00};
	const unsigned char Command2[6] = {0x80, 0x42, 0x00, 0x00, 0x00, 0x00};
	const unsigned char Command3[6] = {0x80, 0x43, 0x00, 0x00, 0x00, 0x00};

	udelay(1000);
	if ((status = sb1000_start_get_set_command(ioaddr, name)))
		return status;

	if ((status = card_send_command(ioaddr, name, Command0, st)))
		return status;
	PID[0] = st[1] << 8 | st[2];

	if ((status = card_send_command(ioaddr, name, Command1, st)))
		return status;
	PID[1] = st[1] << 8 | st[2];

	if ((status = card_send_command(ioaddr, name, Command2, st)))
		return status;
	PID[2] = st[1] << 8 | st[2];

	if ((status = card_send_command(ioaddr, name, Command3, st)))
		return status;
	PID[3] = st[1] << 8 | st[2];

	return sb1000_end_get_set_command(ioaddr, name);
}

/* set SB1000 PIDs */
static int
sb1000_set_PIDs(const int ioaddr[], const char* name, const short PID[])
{
	unsigned char st[7];
	short p;
	int status;
	unsigned char Command0[6] = {0x80, 0x31, 0x00, 0x00, 0x00, 0x00};
	unsigned char Command1[6] = {0x80, 0x32, 0x00, 0x00, 0x00, 0x00};
	unsigned char Command2[6] = {0x80, 0x33, 0x00, 0x00, 0x00, 0x00};
	unsigned char Command3[6] = {0x80, 0x34, 0x00, 0x00, 0x00, 0x00};
	const unsigned char Command4[6] = {0x80, 0x2e, 0x00, 0x00, 0x00, 0x00};

	udelay(1000);
	if ((status = sb1000_start_get_set_command(ioaddr, name)))
		return status;

	p = PID[0];
	Command0[3] = p & 0xff;
	p >>= 8;
	Command0[2] = p & 0xff;
	if ((status = card_send_command(ioaddr, name, Command0, st)))
		return status;

	p = PID[1];
	Command1[3] = p & 0xff;
	p >>= 8;
	Command1[2] = p & 0xff;
	if ((status = card_send_command(ioaddr, name, Command1, st)))
		return status;

	p = PID[2];
	Command2[3] = p & 0xff;
	p >>= 8;
	Command2[2] = p & 0xff;
	if ((status = card_send_command(ioaddr, name, Command2, st)))
		return status;

	p = PID[3];
	Command3[3] = p & 0xff;
	p >>= 8;
	Command3[2] = p & 0xff;
	if ((status = card_send_command(ioaddr, name, Command3, st)))
		return status;

	if ((status = card_send_command(ioaddr, name, Command4, st)))
		return status;
	return sb1000_end_get_set_command(ioaddr, name);
}


static inline void
sb1000_print_status_buffer(const char* name, unsigned char st[],
	unsigned char buffer[], int size)
{
	int i, j, k;

	printk(KERN_DEBUG "%s: status: %02x %02x\n", name, st[0], st[1]);
	if (buffer[24] == 0x08 && buffer[25] == 0x00 && buffer[26] == 0x45) {
		printk(KERN_DEBUG "%s: length: %d protocol: %d from: %d.%d.%d.%d:%d "
			"to %d.%d.%d.%d:%d\n", name, buffer[28] << 8 | buffer[29],
			buffer[35], buffer[38], buffer[39], buffer[40], buffer[41],
            buffer[46] << 8 | buffer[47],
			buffer[42], buffer[43], buffer[44], buffer[45],
            buffer[48] << 8 | buffer[49]);
	} else {
		for (i = 0, k = 0; i < (size + 7) / 8; i++) {
			printk(KERN_DEBUG "%s: %s", name, i ? "       " : "buffer:");
			for (j = 0; j < 8 && k < size; j++, k++)
				printk(" %02x", buffer[k]);
			printk("\n");
		}
	}
	return;
}

/*
 * SB1000 commands for frame rx interrupt
 */
/* receive a single frame and assemble datagram
 * (this is the heart of the interrupt routine)
 */
static inline int
sb1000_rx(struct net_device *dev)
{

#define FRAMESIZE 184
	unsigned char st[2], buffer[FRAMESIZE], session_id, frame_id;
	short dlen;
	int ioaddr, ns;
	unsigned int skbsize;
	struct sk_buff *skb;
	struct sb1000_private *lp = netdev_priv(dev);
	struct net_device_stats *stats = &lp->stats;

	/* SB1000 frame constants */
	const int FrameSize = FRAMESIZE;
	const int NewDatagramHeaderSkip = 8;
	const int NewDatagramHeaderSize = NewDatagramHeaderSkip + 18;
	const int NewDatagramDataSize = FrameSize - NewDatagramHeaderSize;
	const int ContDatagramHeaderSkip = 7;
	const int ContDatagramHeaderSize = ContDatagramHeaderSkip + 1;
	const int ContDatagramDataSize = FrameSize - ContDatagramHeaderSize;
	const int TrailerSize = 4;

	ioaddr = dev->base_addr;

	insw(ioaddr, (unsigned short*) st, 1);
#ifdef XXXDEBUG
printk("cm0: received: %02x %02x\n", st[0], st[1]);
#endif /* XXXDEBUG */
	lp->rx_frames++;

	/* decide if it is a good or bad frame */
	for (ns = 0; ns < NPIDS; ns++) {
		session_id = lp->rx_session_id[ns];
		frame_id = lp->rx_frame_id[ns];
		if (st[0] == session_id) {
			if (st[1] == frame_id || (!frame_id && (st[1] & 0xf0) == 0x30)) {
				goto good_frame;
			} else if ((st[1] & 0xf0) == 0x30 && (st[0] & 0x40)) {
				goto skipped_frame;
			} else {
				goto bad_frame;
			}
		} else if (st[0] == (session_id | 0x40)) {
			if ((st[1] & 0xf0) == 0x30) {
				goto skipped_frame;
			} else {
				goto bad_frame;
			}
		}
	}
	goto bad_frame;

skipped_frame:
	stats->rx_frame_errors++;
	skb = lp->rx_skb[ns];
	if (sb1000_debug > 1)
		printk(KERN_WARNING "%s: missing frame(s): got %02x %02x "
			"expecting %02x %02x\n", dev->name, st[0], st[1],
			skb ? session_id : session_id | 0x40, frame_id);
	if (skb) {
		dev_kfree_skb(skb);
		skb = NULL;
	}

good_frame:
	lp->rx_frame_id[ns] = 0x30 | ((st[1] + 1) & 0x0f);
	/* new datagram */
	if (st[0] & 0x40) {
		/* get data length */
		insw(ioaddr, buffer, NewDatagramHeaderSize / 2);
#ifdef XXXDEBUG
printk("cm0: IP identification: %02x%02x  fragment offset: %02x%02x\n", buffer[30], buffer[31], buffer[32], buffer[33]);
#endif /* XXXDEBUG */
		if (buffer[0] != NewDatagramHeaderSkip) {
			if (sb1000_debug > 1)
				printk(KERN_WARNING "%s: new datagram header skip error: "
					"got %02x expecting %02x\n", dev->name, buffer[0],
					NewDatagramHeaderSkip);
			stats->rx_length_errors++;
			insw(ioaddr, buffer, NewDatagramDataSize / 2);
			goto bad_frame_next;
		}
		dlen = ((buffer[NewDatagramHeaderSkip + 3] & 0x0f) << 8 |
			buffer[NewDatagramHeaderSkip + 4]) - 17;
		if (dlen > SB1000_MRU) {
			if (sb1000_debug > 1)
				printk(KERN_WARNING "%s: datagram length (%d) greater "
					"than MRU (%d)\n", dev->name, dlen, SB1000_MRU);
			stats->rx_length_errors++;
			insw(ioaddr, buffer, NewDatagramDataSize / 2);
			goto bad_frame_next;
		}
		lp->rx_dlen[ns] = dlen;
		/* compute size to allocate for datagram */
		skbsize = dlen + FrameSize;
		if ((skb = alloc_skb(skbsize, GFP_ATOMIC)) == NULL) {
			if (sb1000_debug > 1)
				printk(KERN_WARNING "%s: can't allocate %d bytes long "
					"skbuff\n", dev->name, skbsize);
			stats->rx_dropped++;
			insw(ioaddr, buffer, NewDatagramDataSize / 2);
			goto dropped_frame;
		}
		skb->dev = dev;
		skb->mac.raw = skb->data;
		skb->protocol = (unsigned short) buffer[NewDatagramHeaderSkip + 16];
		insw(ioaddr, skb_put(skb, NewDatagramDataSize),
			NewDatagramDataSize / 2);
		lp->rx_skb[ns] = skb;
	} else {
		/* continuation of previous datagram */
		insw(ioaddr, buffer, ContDatagramHeaderSize / 2);
		if (buffer[0] != ContDatagramHeaderSkip) {
			if (sb1000_debug > 1)
				printk(KERN_WARNING "%s: cont datagram header skip error: "
					"got %02x expecting %02x\n", dev->name, buffer[0],
					ContDatagramHeaderSkip);
			stats->rx_length_errors++;
			insw(ioaddr, buffer, ContDatagramDataSize / 2);
			goto bad_frame_next;
		}
		skb = lp->rx_skb[ns];
		insw(ioaddr, skb_put(skb, ContDatagramDataSize),
			ContDatagramDataSize / 2);
		dlen = lp->rx_dlen[ns];
	}
	if (skb->len < dlen + TrailerSize) {
		lp->rx_session_id[ns] &= ~0x40;
		return 0;
	}

	/* datagram completed: send to upper level */
	skb_trim(skb, dlen);
	netif_rx(skb);
	dev->last_rx = jiffies;
	stats->rx_bytes+=dlen;
	stats->rx_packets++;
	lp->rx_skb[ns] = NULL;
	lp->rx_session_id[ns] |= 0x40;
	return 0;

bad_frame:
	insw(ioaddr, buffer, FrameSize / 2);
	if (sb1000_debug > 1)
		printk(KERN_WARNING "%s: frame error: got %02x %02x\n",
			dev->name, st[0], st[1]);
	stats->rx_frame_errors++;
bad_frame_next:
	if (sb1000_debug > 2)
		sb1000_print_status_buffer(dev->name, st, buffer, FrameSize);
dropped_frame:
	stats->rx_errors++;
	if (ns < NPIDS) {
		if ((skb = lp->rx_skb[ns])) {
			dev_kfree_skb(skb);
			lp->rx_skb[ns] = NULL;
		}
		lp->rx_session_id[ns] |= 0x40;
	}
	return -1;
}

static inline void
sb1000_error_dpc(struct net_device *dev)
{
	char *name;
	unsigned char st[5];
	int ioaddr[2];
	struct sb1000_private *lp = netdev_priv(dev);
	const unsigned char Command0[6] = {0x80, 0x26, 0x00, 0x00, 0x00, 0x00};
	const int ErrorDpcCounterInitialize = 200;

	ioaddr[0] = dev->base_addr;
	/* mem_start holds the second I/O address */
	ioaddr[1] = dev->mem_start;
	name = dev->name;

	sb1000_wait_for_ready_clear(ioaddr, name);
	sb1000_send_command(ioaddr, name, Command0);
	sb1000_wait_for_ready(ioaddr, name);
	sb1000_read_status(ioaddr, st);
	if (st[1] & 0x10)
		lp->rx_error_dpc_count = ErrorDpcCounterInitialize;
	return;
}


/*
 * Linux interface functions
 */
static int
sb1000_open(struct net_device *dev)
{
	char *name;
	int ioaddr[2], status;
	struct sb1000_private *lp = netdev_priv(dev);
	const unsigned short FirmwareVersion[] = {0x01, 0x01};

	ioaddr[0] = dev->base_addr;
	/* mem_start holds the second I/O address */
	ioaddr[1] = dev->mem_start;
	name = dev->name;

	/* initialize sb1000 */
	if ((status = sb1000_reset(ioaddr, name)))
		return status;
	ssleep(1);
	if ((status = sb1000_check_CRC(ioaddr, name)))
		return status;

	/* initialize private data before board can catch interrupts */
	lp->rx_skb[0] = NULL;
	lp->rx_skb[1] = NULL;
	lp->rx_skb[2] = NULL;
	lp->rx_skb[3] = NULL;
	lp->rx_dlen[0] = 0;
	lp->rx_dlen[1] = 0;
	lp->rx_dlen[2] = 0;
	lp->rx_dlen[3] = 0;
	lp->rx_frames = 0;
	lp->rx_error_count = 0;
	lp->rx_error_dpc_count = 0;
	lp->rx_session_id[0] = 0x50;
	lp->rx_session_id[0] = 0x48;
	lp->rx_session_id[0] = 0x44;
	lp->rx_session_id[0] = 0x42;
	lp->rx_frame_id[0] = 0;
	lp->rx_frame_id[1] = 0;
	lp->rx_frame_id[2] = 0;
	lp->rx_frame_id[3] = 0;
	if (request_irq(dev->irq, &sb1000_interrupt, 0, "sb1000", dev)) {
		return -EAGAIN;
	}

	if (sb1000_debug > 2)
		printk(KERN_DEBUG "%s: Opening, IRQ %d\n", name, dev->irq);

	/* Activate board and check firmware version */
	udelay(1000);
	if ((status = sb1000_activate(ioaddr, name)))
		return status;
	udelay(0);
	if ((status = sb1000_get_firmware_version(ioaddr, name, version, 0)))
		return status;
	if (version[0] != FirmwareVersion[0] || version[1] != FirmwareVersion[1])
		printk(KERN_WARNING "%s: found firmware version %x.%02x "
			"(should be %x.%02x)\n", name, version[0], version[1],
			FirmwareVersion[0], FirmwareVersion[1]);


	netif_start_queue(dev);
	return 0;					/* Always succeed */
}

static int sb1000_dev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
{
	char* name;
	unsigned char version[2];
	short PID[4];
	int ioaddr[2], status, frequency;
	unsigned int stats[5];
	struct sb1000_private *lp = netdev_priv(dev);

	if (!(dev && dev->flags & IFF_UP))
		return -ENODEV;

	ioaddr[0] = dev->base_addr;
	/* mem_start holds the second I/O address */
	ioaddr[1] = dev->mem_start;
	name = dev->name;

	switch (cmd) {
	case SIOCGCMSTATS:		/* get statistics */
		stats[0] = lp->stats.rx_bytes;
		stats[1] = lp->rx_frames;
		stats[2] = lp->stats.rx_packets;
		stats[3] = lp->stats.rx_errors;
		stats[4] = lp->stats.rx_dropped;
		if(copy_to_user(ifr->ifr_data, stats, sizeof(stats)))
			return -EFAULT;
		status = 0;
		break;

	case SIOCGCMFIRMWARE:		/* get firmware version */
		if ((status = sb1000_get_firmware_version(ioaddr, name, version, 1)))
			return status;
		if(copy_to_user(ifr->ifr_data, version, sizeof(version)))
			return -EFAULT;
		break;

	case SIOCGCMFREQUENCY:		/* get frequency */
		if ((status = sb1000_get_frequency(ioaddr, name, &frequency)))
			return status;
		if(put_user(frequency, (int __user *) ifr->ifr_data))
			return -EFAULT;
		break;

	case SIOCSCMFREQUENCY:		/* set frequency */
		if (!capable(CAP_NET_ADMIN))
			return -EPERM;
		if(get_user(frequency, (int __user *) ifr->ifr_data))
			return -EFAULT;
		if ((status = sb1000_set_frequency(ioaddr, name, frequency)))
			return status;
		break;

	case SIOCGCMPIDS:			/* get PIDs */
		if ((status = sb1000_get_PIDs(ioaddr, name, PID)))
			return status;
		if(copy_to_user(ifr->ifr_data, PID, sizeof(PID)))
			return -EFAULT;
		break;

	case SIOCSCMPIDS:			/* set PIDs */
		if (!capable(CAP_NET_ADMIN))
			return -EPERM;
		if(copy_from_user(PID, ifr->ifr_data, sizeof(PID)))
			return -EFAULT;
		if ((status = sb1000_set_PIDs(ioaddr, name, PID)))
			return status;
		/* set session_id, frame_id and pkt_type too */
		lp->rx_session_id[0] = 0x50 | (PID[0] & 0x0f);
		lp->rx_session_id[1] = 0x48;
		lp->rx_session_id[2] = 0x44;
		lp->rx_session_id[3] = 0x42;
		lp->rx_frame_id[0] = 0;
		lp->rx_frame_id[1] = 0;
		lp->rx_frame_id[2] = 0;
		lp->rx_frame_id[3] = 0;
		break;

	default:
		status = -EINVAL;
		break;
	}
	return status;
}

/* transmit function: do nothing since SB1000 can't send anything out */
static int
sb1000_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
	printk(KERN_WARNING "%s: trying to transmit!!!\n", dev->name);
	/* sb1000 can't xmit datagrams */
	dev_kfree_skb(skb);
	return 0;
}

/* SB1000 interrupt handler. */
static irqreturn_t sb1000_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
	char *name;
	unsigned char st;
	int ioaddr[2];
	struct net_device *dev = (struct net_device *) dev_id;
	struct sb1000_private *lp = netdev_priv(dev);

	const unsigned char Command0[6] = {0x80, 0x2c, 0x00, 0x00, 0x00, 0x00};
	const unsigned char Command1[6] = {0x80, 0x2e, 0x00, 0x00, 0x00, 0x00};
	const int MaxRxErrorCount = 6;

	if (dev == NULL) {
		printk(KERN_ERR "sb1000_interrupt(): irq %d for unknown device.\n",
			irq);
		return IRQ_NONE;
	}

	ioaddr[0] = dev->base_addr;
	/* mem_start holds the second I/O address */
	ioaddr[1] = dev->mem_start;
	name = dev->name;

	/* is it a good interrupt? */
	st = inb(ioaddr[1] + 6);
	if (!(st & 0x08 && st & 0x20)) {
		return IRQ_NONE;
	}

	if (sb1000_debug > 3)
		printk(KERN_DEBUG "%s: entering interrupt\n", dev->name);

	st = inb(ioaddr[0] + 7);
	if (sb1000_rx(dev))
		lp->rx_error_count++;
#ifdef SB1000_DELAY
	udelay(SB1000_DELAY);
#endif /* SB1000_DELAY */
	sb1000_issue_read_command(ioaddr, name);
	if (st & 0x01) {
		sb1000_error_dpc(dev);
		sb1000_issue_read_command(ioaddr, name);
	}
	if (lp->rx_error_dpc_count && !(--lp->rx_error_dpc_count)) {
		sb1000_wait_for_ready_clear(ioaddr, name);
		sb1000_send_command(ioaddr, name, Command0);
		sb1000_wait_for_ready(ioaddr, name);
		sb1000_issue_read_command(ioaddr, name);
	}
	if (lp->rx_error_count >= MaxRxErrorCount) {
		sb1000_wait_for_ready_clear(ioaddr, name);
		sb1000_send_command(ioaddr, name, Command1);
		sb1000_wait_for_ready(ioaddr, name);
		sb1000_issue_read_command(ioaddr, name);
		lp->rx_error_count = 0;
	}

	return IRQ_HANDLED;
}

static struct net_device_stats *sb1000_stats(struct net_device *dev)
{
	struct sb1000_private *lp = netdev_priv(dev);
	return &lp->stats;
}

static int sb1000_close(struct net_device *dev)
{
	int i;
	int ioaddr[2];
	struct sb1000_private *lp = netdev_priv(dev);

	if (sb1000_debug > 2)
		printk(KERN_DEBUG "%s: Shutting down sb1000.\n", dev->name);

	netif_stop_queue(dev);
	
	ioaddr[0] = dev->base_addr;
	/* mem_start holds the second I/O address */
	ioaddr[1] = dev->mem_start;

	free_irq(dev->irq, dev);
	/* If we don't do this, we can't re-insmod it later. */
	release_region(ioaddr[1], SB1000_IO_EXTENT);
	release_region(ioaddr[0], SB1000_IO_EXTENT);

	/* free rx_skb's if needed */
	for (i=0; i<4; i++) {
		if (lp->rx_skb[i]) {
			dev_kfree_skb(lp->rx_skb[i]);
		}
	}
	return 0;
}

MODULE_AUTHOR("Franco Venturi <fventuri@mediaone.net>");
MODULE_DESCRIPTION("General Instruments SB1000 driver");
MODULE_LICENSE("GPL");

static int __init
sb1000_init(void)
{
	return pnp_register_driver(&sb1000_driver);
}

static void __exit
sb1000_exit(void)
{
	pnp_unregister_driver(&sb1000_driver);
}

module_init(sb1000_init);
module_exit(sb1000_exit);