drivers/net/arcnet/com90xx.c - LeafOS-Devices/android_kernel_samsung_gta4xl - Gitiles

 /*
  * Linux ARCnet driver - COM90xx chipset (memory-mapped buffers)
  *
  * Written 1994-1999 by Avery Pennarun.
  * Written 1999 by Martin Mares <mj@ucw.cz>.
  * Derived from skeleton.c by Donald Becker.
  *
  * Special thanks to Contemporary Controls, Inc. (www.ccontrols.com)
  *  for sponsoring the further development of this driver.
  *
  * **********************
  *
  * The original copyright of skeleton.c was as follows:
  *
  * skeleton.c Written 1993 by Donald Becker.
  * Copyright 1993 United States Government as represented by the
  * Director, National Security Agency.  This software may only be used
  * and distributed according to the terms of the GNU General Public License as
  * modified by SRC, incorporated herein by reference.
  *
  * **********************
  *
  * For more details, see drivers/net/arcnet.c
  *
  * **********************
  */
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/init.h>
 #include <linux/ioport.h>
 #include <linux/delay.h>
 #include <linux/netdevice.h>
 #include <asm/io.h>
 #include <linux/arcdevice.h>


 #define VERSION "arcnet: COM90xx chipset support\n"


 /* Define this to speed up the autoprobe by assuming if only one io port and
  * shmem are left in the list at Stage 5, they must correspond to each
  * other.
  *
  * This is undefined by default because it might not always be true, and the
  * extra check makes the autoprobe even more careful.  Speed demons can turn
  * it on - I think it should be fine if you only have one ARCnet card
  * installed.
  *
  * If no ARCnet cards are installed, this delay never happens anyway and thus
  * the option has no effect.
  */
 #undef FAST_PROBE


 /* Internal function declarations */
 static int com90xx_found(int ioaddr, int airq, u_long shmem, void __iomem *);
 static void com90xx_command(struct net_device *dev, int command);
 static int com90xx_status(struct net_device *dev);
 static void com90xx_setmask(struct net_device *dev, int mask);
 static int com90xx_reset(struct net_device *dev, int really_reset);
 static void com90xx_copy_to_card(struct net_device *dev, int bufnum, int offset,
 				 void *buf, int count);
 static void com90xx_copy_from_card(struct net_device *dev, int bufnum, int offset,
 				   void *buf, int count);

 /* Known ARCnet cards */

 static struct net_device *cards[16];
 static int numcards;

 /* Handy defines for ARCnet specific stuff */

 /* The number of low I/O ports used by the card */
 #define ARCNET_TOTAL_SIZE	16

 /* Amount of I/O memory used by the card */
 #define BUFFER_SIZE (512)
 #define MIRROR_SIZE (BUFFER_SIZE*4)

 /* COM 9026 controller chip --> ARCnet register addresses */
 #define _INTMASK (ioaddr+0)	/* writable */
 #define _STATUS  (ioaddr+0)	/* readable */
 #define _COMMAND (ioaddr+1)	/* writable, returns random vals on read (?) */
 #define _CONFIG  (ioaddr+2)	/* Configuration register */
 #define _RESET   (ioaddr+8)	/* software reset (on read) */
 #define _MEMDATA (ioaddr+12)	/* Data port for IO-mapped memory */
 #define _ADDR_HI (ioaddr+15)	/* Control registers for said */
 #define _ADDR_LO (ioaddr+14)

 #undef ASTATUS
 #undef ACOMMAND
 #undef AINTMASK

 #define ASTATUS()	inb(_STATUS)
 #define ACOMMAND(cmd) 	outb((cmd),_COMMAND)
 #define AINTMASK(msk)	outb((msk),_INTMASK)


 static int com90xx_skip_probe __initdata = 0;

 /* Module parameters */

 static int io;			/* use the insmod io= irq= shmem= options */
 static int irq;
 static int shmem;
 static char device[9];		/* use eg. device=arc1 to change name */

 module_param(io, int, 0);
 module_param(irq, int, 0);
 module_param(shmem, int, 0);
 module_param_string(device, device, sizeof(device), 0);

 static void __init com90xx_probe(void)
 {
 	int count, status, ioaddr, numprint, airq, openparen = 0;
 	unsigned long airqmask;
 	int ports[(0x3f0 - 0x200) / 16 + 1] =
 	{0};
 	unsigned long *shmems;
 	void __iomem **iomem;
 	int numports, numshmems, *port;
 	u_long *p;
 	int index;

 	if (!io && !irq && !shmem && !*device && com90xx_skip_probe)
 		return;

 	shmems = kzalloc(((0x10000-0xa0000) / 0x800) * sizeof(unsigned long),
 			 GFP_KERNEL);
 	if (!shmems)
 		return;
 	iomem = kzalloc(((0x10000-0xa0000) / 0x800) * sizeof(void __iomem *),
 			 GFP_KERNEL);
 	if (!iomem) {
 		kfree(shmems);
 		return;
 	}

 	BUGLVL(D_NORMAL) printk(VERSION);

 	/* set up the arrays where we'll store the possible probe addresses */
 	numports = numshmems = 0;
 	if (io)
 		ports[numports++] = io;
 	else
 		for (count = 0x200; count <= 0x3f0; count += 16)
 			ports[numports++] = count;
 	if (shmem)
 		shmems[numshmems++] = shmem;
 	else
 		for (count = 0xA0000; count <= 0xFF800; count += 2048)
 			shmems[numshmems++] = count;

 	/* Stage 1: abandon any reserved ports, or ones with status==0xFF
 	 * (empty), and reset any others by reading the reset port.
 	 */
 	numprint = -1;
 	for (port = &ports[0]; port - ports < numports; port++) {
 		numprint++;
 		numprint %= 8;
 		if (!numprint) {
 			BUGMSG2(D_INIT, "\n");
 			BUGMSG2(D_INIT, "S1: ");
 		}
 		BUGMSG2(D_INIT, "%Xh ", *port);

 		ioaddr = *port;

 		if (!request_region(*port, ARCNET_TOTAL_SIZE, "arcnet (90xx)")) {
 			BUGMSG2(D_INIT_REASONS, "(request_region)\n");
 			BUGMSG2(D_INIT_REASONS, "S1: ");
 			BUGLVL(D_INIT_REASONS) numprint = 0;
 			*port-- = ports[--numports];
 			continue;
 		}
 		if (ASTATUS() == 0xFF) {
 			BUGMSG2(D_INIT_REASONS, "(empty)\n");
 			BUGMSG2(D_INIT_REASONS, "S1: ");
 			BUGLVL(D_INIT_REASONS) numprint = 0;
 			release_region(*port, ARCNET_TOTAL_SIZE);
 			*port-- = ports[--numports];
 			continue;
 		}
 		inb(_RESET);	/* begin resetting card */

 		BUGMSG2(D_INIT_REASONS, "\n");
 		BUGMSG2(D_INIT_REASONS, "S1: ");
 		BUGLVL(D_INIT_REASONS) numprint = 0;
 	}
 	BUGMSG2(D_INIT, "\n");

 	if (!numports) {
 		BUGMSG2(D_NORMAL, "S1: No ARCnet cards found.\n");
 		kfree(shmems);
 		kfree(iomem);
 		return;
 	}
 	/* Stage 2: we have now reset any possible ARCnet cards, so we can't
 	 * do anything until they finish.  If D_INIT, print the list of
 	 * cards that are left.
 	 */
 	numprint = -1;
 	for (port = &ports[0]; port < ports + numports; port++) {
 		numprint++;
 		numprint %= 8;
 		if (!numprint) {
 			BUGMSG2(D_INIT, "\n");
 			BUGMSG2(D_INIT, "S2: ");
 		}
 		BUGMSG2(D_INIT, "%Xh ", *port);
 	}
 	BUGMSG2(D_INIT, "\n");
 	mdelay(RESETtime);

 	/* Stage 3: abandon any shmem addresses that don't have the signature
 	 * 0xD1 byte in the right place, or are read-only.
 	 */
 	numprint = -1;
 	for (index = 0, p = &shmems[0]; index < numshmems; p++, index++) {
 		void __iomem *base;

 		numprint++;
 		numprint %= 8;
 		if (!numprint) {
 			BUGMSG2(D_INIT, "\n");
 			BUGMSG2(D_INIT, "S3: ");
 		}
 		BUGMSG2(D_INIT, "%lXh ", *p);

 		if (!request_mem_region(*p, MIRROR_SIZE, "arcnet (90xx)")) {
 			BUGMSG2(D_INIT_REASONS, "(request_mem_region)\n");
 			BUGMSG2(D_INIT_REASONS, "Stage 3: ");
 			BUGLVL(D_INIT_REASONS) numprint = 0;
 			goto out;
 		}
 		base = ioremap(*p, MIRROR_SIZE);
 		if (!base) {
 			BUGMSG2(D_INIT_REASONS, "(ioremap)\n");
 			BUGMSG2(D_INIT_REASONS, "Stage 3: ");
 			BUGLVL(D_INIT_REASONS) numprint = 0;
 			goto out1;
 		}
 		if (readb(base) != TESTvalue) {
 			BUGMSG2(D_INIT_REASONS, "(%02Xh != %02Xh)\n",
 				readb(base), TESTvalue);
 			BUGMSG2(D_INIT_REASONS, "S3: ");
 			BUGLVL(D_INIT_REASONS) numprint = 0;
 			goto out2;
 		}
 		/* By writing 0x42 to the TESTvalue location, we also make
 		 * sure no "mirror" shmem areas show up - if they occur
 		 * in another pass through this loop, they will be discarded
 		 * because *cptr != TESTvalue.
 		 */
 		writeb(0x42, base);
 		if (readb(base) != 0x42) {
 			BUGMSG2(D_INIT_REASONS, "(read only)\n");
 			BUGMSG2(D_INIT_REASONS, "S3: ");
 			goto out2;
 		}
 		BUGMSG2(D_INIT_REASONS, "\n");
 		BUGMSG2(D_INIT_REASONS, "S3: ");
 		BUGLVL(D_INIT_REASONS) numprint = 0;
 		iomem[index] = base;
 		continue;
 	out2:
 		iounmap(base);
 	out1:
 		release_mem_region(*p, MIRROR_SIZE);
 	out:
 		*p-- = shmems[--numshmems];
 		index--;
 	}
 	BUGMSG2(D_INIT, "\n");

 	if (!numshmems) {
 		BUGMSG2(D_NORMAL, "S3: No ARCnet cards found.\n");
 		for (port = &ports[0]; port < ports + numports; port++)
 			release_region(*port, ARCNET_TOTAL_SIZE);
 		kfree(shmems);
 		kfree(iomem);
 		return;
 	}
 	/* Stage 4: something of a dummy, to report the shmems that are
 	 * still possible after stage 3.
 	 */
 	numprint = -1;
 	for (p = &shmems[0]; p < shmems + numshmems; p++) {
 		numprint++;
 		numprint %= 8;
 		if (!numprint) {
 			BUGMSG2(D_INIT, "\n");
 			BUGMSG2(D_INIT, "S4: ");
 		}
 		BUGMSG2(D_INIT, "%lXh ", *p);
 	}
 	BUGMSG2(D_INIT, "\n");

 	/* Stage 5: for any ports that have the correct status, can disable
 	 * the RESET flag, and (if no irq is given) generate an autoirq,
 	 * register an ARCnet device.
 	 *
 	 * Currently, we can only register one device per probe, so quit
 	 * after the first one is found.
 	 */
 	numprint = -1;
 	for (port = &ports[0]; port < ports + numports; port++) {
 		int found = 0;
 		numprint++;
 		numprint %= 8;
 		if (!numprint) {
 			BUGMSG2(D_INIT, "\n");
 			BUGMSG2(D_INIT, "S5: ");
 		}
 		BUGMSG2(D_INIT, "%Xh ", *port);

 		ioaddr = *port;
 		status = ASTATUS();

 		if ((status & 0x9D)
 		    != (NORXflag | RECONflag | TXFREEflag | RESETflag)) {
 			BUGMSG2(D_INIT_REASONS, "(status=%Xh)\n", status);
 			BUGMSG2(D_INIT_REASONS, "S5: ");
 			BUGLVL(D_INIT_REASONS) numprint = 0;
 			release_region(*port, ARCNET_TOTAL_SIZE);
 			*port-- = ports[--numports];
 			continue;
 		}
 		ACOMMAND(CFLAGScmd | RESETclear | CONFIGclear);
 		status = ASTATUS();
 		if (status & RESETflag) {
 			BUGMSG2(D_INIT_REASONS, " (eternal reset, status=%Xh)\n",
 				status);
 			BUGMSG2(D_INIT_REASONS, "S5: ");
 			BUGLVL(D_INIT_REASONS) numprint = 0;
 			release_region(*port, ARCNET_TOTAL_SIZE);
 			*port-- = ports[--numports];
 			continue;
 		}
 		/* skip this completely if an IRQ was given, because maybe
 		 * we're on a machine that locks during autoirq!
 		 */
 		if (!irq) {
 			/* if we do this, we're sure to get an IRQ since the
 			 * card has just reset and the NORXflag is on until
 			 * we tell it to start receiving.
 			 */
 			airqmask = probe_irq_on();
 			AINTMASK(NORXflag);
 			udelay(1);
 			AINTMASK(0);
 			airq = probe_irq_off(airqmask);

 			if (airq <= 0) {
 				BUGMSG2(D_INIT_REASONS, "(airq=%d)\n", airq);
 				BUGMSG2(D_INIT_REASONS, "S5: ");
 				BUGLVL(D_INIT_REASONS) numprint = 0;
 				release_region(*port, ARCNET_TOTAL_SIZE);
 				*port-- = ports[--numports];
 				continue;
 			}
 		} else {
 			airq = irq;
 		}

 		BUGMSG2(D_INIT, "(%d,", airq);
 		openparen = 1;

 		/* Everything seems okay.  But which shmem, if any, puts
 		 * back its signature byte when the card is reset?
 		 *
 		 * If there are multiple cards installed, there might be
 		 * multiple shmems still in the list.
 		 */
 #ifdef FAST_PROBE
 		if (numports > 1 || numshmems > 1) {
 			inb(_RESET);
 			mdelay(RESETtime);
 		} else {
 			/* just one shmem and port, assume they match */
 			writeb(TESTvalue, iomem[0]);
 		}
 #else
 		inb(_RESET);
 		mdelay(RESETtime);
 #endif

 		for (index = 0; index < numshmems; index++) {
 			u_long ptr = shmems[index];
 			void __iomem *base = iomem[index];

 			if (readb(base) == TESTvalue) {	/* found one */
 				BUGMSG2(D_INIT, "%lXh)\n", *p);
 				openparen = 0;

 				/* register the card */
 				if (com90xx_found(*port, airq, ptr, base) == 0)
 					found = 1;
 				numprint = -1;

 				/* remove shmem from the list */
 				shmems[index] = shmems[--numshmems];
 				iomem[index] = iomem[numshmems];
 				break;	/* go to the next I/O port */
 			} else {
 				BUGMSG2(D_INIT_REASONS, "%Xh-", readb(base));
 			}
 		}

 		if (openparen) {
 			BUGLVL(D_INIT) printk("no matching shmem)\n");
 			BUGLVL(D_INIT_REASONS) printk("S5: ");
 			BUGLVL(D_INIT_REASONS) numprint = 0;
 		}
 		if (!found)
 			release_region(*port, ARCNET_TOTAL_SIZE);
 		*port-- = ports[--numports];
 	}

 	BUGLVL(D_INIT_REASONS) printk("\n");

 	/* Now put back TESTvalue on all leftover shmems. */
 	for (index = 0; index < numshmems; index++) {
 		writeb(TESTvalue, iomem[index]);
 		iounmap(iomem[index]);
 		release_mem_region(shmems[index], MIRROR_SIZE);
 	}
 	kfree(shmems);
 	kfree(iomem);
 }

 static int check_mirror(unsigned long addr, size_t size)
 {
 	void __iomem *p;
 	int res = -1;

 	if (!request_mem_region(addr, size, "arcnet (90xx)"))
 		return -1;

 	p = ioremap(addr, size);
 	if (p) {
 		if (readb(p) == TESTvalue)
 			res = 1;
 		else
 			res = 0;
 		iounmap(p);
 	}

 	release_mem_region(addr, size);
 	return res;
 }

 /* Set up the struct net_device associated with this card.  Called after
  * probing succeeds.
  */
 static int __init com90xx_found(int ioaddr, int airq, u_long shmem, void __iomem *p)
 {
 	struct net_device *dev = NULL;
 	struct arcnet_local *lp;
 	u_long first_mirror, last_mirror;
 	int mirror_size;

 	/* allocate struct net_device */
 	dev = alloc_arcdev(device);
 	if (!dev) {
 		BUGMSG2(D_NORMAL, "com90xx: Can't allocate device!\n");
 		iounmap(p);
 		release_mem_region(shmem, MIRROR_SIZE);
 		return -ENOMEM;
 	}
 	lp = dev->priv;
 	/* find the real shared memory start/end points, including mirrors */

 	/* guess the actual size of one "memory mirror" - the number of
 	 * bytes between copies of the shared memory.  On most cards, it's
 	 * 2k (or there are no mirrors at all) but on some, it's 4k.
 	 */
 	mirror_size = MIRROR_SIZE;
 	if (readb(p) == TESTvalue &&
 	    check_mirror(shmem - MIRROR_SIZE, MIRROR_SIZE) == 0 &&
 	    check_mirror(shmem - 2 * MIRROR_SIZE, MIRROR_SIZE) == 1)
 		mirror_size = 2 * MIRROR_SIZE;

 	first_mirror = shmem - mirror_size;
 	while (check_mirror(first_mirror, mirror_size) == 1)
 		first_mirror -= mirror_size;
 	first_mirror += mirror_size;

 	last_mirror = shmem + mirror_size;
 	while (check_mirror(last_mirror, mirror_size) == 1)
 		last_mirror += mirror_size;
 	last_mirror -= mirror_size;

 	dev->mem_start = first_mirror;
 	dev->mem_end = last_mirror + MIRROR_SIZE - 1;

 	iounmap(p);
 	release_mem_region(shmem, MIRROR_SIZE);

 	if (!request_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1, "arcnet (90xx)"))
 		goto err_free_dev;

 	/* reserve the irq */
 	if (request_irq(airq, &arcnet_interrupt, 0, "arcnet (90xx)", dev)) {
 		BUGMSG(D_NORMAL, "Can't get IRQ %d!\n", airq);
 		goto err_release_mem;
 	}
 	dev->irq = airq;

 	/* Initialize the rest of the device structure. */
 	lp->card_name = "COM90xx";
 	lp->hw.command = com90xx_command;
 	lp->hw.status = com90xx_status;
 	lp->hw.intmask = com90xx_setmask;
 	lp->hw.reset = com90xx_reset;
 	lp->hw.owner = THIS_MODULE;
 	lp->hw.copy_to_card = com90xx_copy_to_card;
 	lp->hw.copy_from_card = com90xx_copy_from_card;
 	lp->mem_start = ioremap(dev->mem_start, dev->mem_end - dev->mem_start + 1);
 	if (!lp->mem_start) {
 		BUGMSG(D_NORMAL, "Can't remap device memory!\n");
 		goto err_free_irq;
 	}

 	/* get and check the station ID from offset 1 in shmem */
 	dev->dev_addr[0] = readb(lp->mem_start + 1);

 	dev->base_addr = ioaddr;

 	BUGMSG(D_NORMAL, "COM90xx station %02Xh found at %03lXh, IRQ %d, "
 	       "ShMem %lXh (%ld*%xh).\n",
 	       dev->dev_addr[0],
 	       dev->base_addr, dev->irq, dev->mem_start,
 	 (dev->mem_end - dev->mem_start + 1) / mirror_size, mirror_size);

 	if (register_netdev(dev))
 		goto err_unmap;

 	cards[numcards++] = dev;
 	return 0;

 err_unmap:
 	iounmap(lp->mem_start);
 err_free_irq:
 	free_irq(dev->irq, dev);
 err_release_mem:
 	release_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1);
 err_free_dev:
 	free_netdev(dev);
 	return -EIO;
 }


 static void com90xx_command(struct net_device *dev, int cmd)
 {
 	short ioaddr = dev->base_addr;

 	ACOMMAND(cmd);
 }


 static int com90xx_status(struct net_device *dev)
 {
 	short ioaddr = dev->base_addr;

 	return ASTATUS();
 }


 static void com90xx_setmask(struct net_device *dev, int mask)
 {
 	short ioaddr = dev->base_addr;

 	AINTMASK(mask);
 }


 /*
  * Do a hardware reset on the card, and set up necessary registers.
  *
  * This should be called as little as possible, because it disrupts the
  * token on the network (causes a RECON) and requires a significant delay.
  *
  * However, it does make sure the card is in a defined state.
  */
 int com90xx_reset(struct net_device *dev, int really_reset)
 {
 	struct arcnet_local *lp = dev->priv;
 	short ioaddr = dev->base_addr;

 	BUGMSG(D_INIT, "Resetting (status=%02Xh)\n", ASTATUS());

 	if (really_reset) {
 		/* reset the card */
 		inb(_RESET);
 		mdelay(RESETtime);
 	}
 	ACOMMAND(CFLAGScmd | RESETclear);	/* clear flags & end reset */
 	ACOMMAND(CFLAGScmd | CONFIGclear);

 	/* don't do this until we verify that it doesn't hurt older cards! */
 	/* outb(inb(_CONFIG) | ENABLE16flag, _CONFIG); */

 	/* verify that the ARCnet signature byte is present */
 	if (readb(lp->mem_start) != TESTvalue) {
 		if (really_reset)
 			BUGMSG(D_NORMAL, "reset failed: TESTvalue not present.\n");
 		return 1;
 	}
 	/* enable extended (512-byte) packets */
 	ACOMMAND(CONFIGcmd | EXTconf);

 	/* clean out all the memory to make debugging make more sense :) */
 	BUGLVL(D_DURING)
 	    memset_io(lp->mem_start, 0x42, 2048);

 	/* done!  return success. */
 	return 0;
 }

 static void com90xx_copy_to_card(struct net_device *dev, int bufnum, int offset,
 				 void *buf, int count)
 {
 	struct arcnet_local *lp = dev->priv;
 	void __iomem *memaddr = lp->mem_start + bufnum * 512 + offset;
 	TIME("memcpy_toio", count, memcpy_toio(memaddr, buf, count));
 }


 static void com90xx_copy_from_card(struct net_device *dev, int bufnum, int offset,
 				   void *buf, int count)
 {
 	struct arcnet_local *lp = dev->priv;
 	void __iomem *memaddr = lp->mem_start + bufnum * 512 + offset;
 	TIME("memcpy_fromio", count, memcpy_fromio(buf, memaddr, count));
 }


 MODULE_LICENSE("GPL");

 static int __init com90xx_init(void)
 {
 	if (irq == 2)
 		irq = 9;
 	com90xx_probe();
 	if (!numcards)
 		return -EIO;
 	return 0;
 }

 static void __exit com90xx_exit(void)
 {
 	struct net_device *dev;
 	struct arcnet_local *lp;
 	int count;

 	for (count = 0; count < numcards; count++) {
 		dev = cards[count];
 		lp = dev->priv;

 		unregister_netdev(dev);
 		free_irq(dev->irq, dev);
 		iounmap(lp->mem_start);
 		release_region(dev->base_addr, ARCNET_TOTAL_SIZE);
 		release_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1);
 		free_netdev(dev);
 	}
 }

 module_init(com90xx_init);
 module_exit(com90xx_exit);

 #ifndef MODULE
 static int __init com90xx_setup(char *s)
 {
 	int ints[8];

 	s = get_options(s, 8, ints);
 	if (!ints[0] && !*s) {
 		printk("com90xx: Disabled.\n");
 		return 1;
 	}

 	switch (ints[0]) {
 	default:		/* ERROR */
 		printk("com90xx: Too many arguments.\n");
 	case 3:		/* Mem address */
 		shmem = ints[3];
 	case 2:		/* IRQ */
 		irq = ints[2];
 	case 1:		/* IO address */
 		io = ints[1];
 	}

 	if (*s)
 		snprintf(device, sizeof(device), "%s", s);

 	return 1;
 }

 __setup("com90xx=", com90xx_setup);
 #endif
	/*
	* Linux ARCnet driver - COM90xx chipset (memory-mapped buffers)
	*
	* Written 1994-1999 by Avery Pennarun.
	* Written 1999 by Martin Mares <mj@ucw.cz>.
	* Derived from skeleton.c by Donald Becker.
	*
	* Special thanks to Contemporary Controls, Inc. (www.ccontrols.com)
	* for sponsoring the further development of this driver.
	*
	* **********************
	*
	* The original copyright of skeleton.c was as follows:
	*
	* skeleton.c Written 1993 by Donald Becker.
	* Copyright 1993 United States Government as represented by the
	* Director, National Security Agency. This software may only be used
	* and distributed according to the terms of the GNU General Public License as
	* modified by SRC, incorporated herein by reference.
	*
	* **********************
	*
	* For more details, see drivers/net/arcnet.c
	*
	* **********************
	*/
	#include <linux/module.h>
	#include <linux/moduleparam.h>
	#include <linux/init.h>
	#include <linux/ioport.h>
	#include <linux/delay.h>
	#include <linux/netdevice.h>
	#include <asm/io.h>
	#include <linux/arcdevice.h>


	#define VERSION "arcnet: COM90xx chipset support\n"


	/* Define this to speed up the autoprobe by assuming if only one io port and
	* shmem are left in the list at Stage 5, they must correspond to each
	* other.
	*
	* This is undefined by default because it might not always be true, and the
	* extra check makes the autoprobe even more careful. Speed demons can turn
	* it on - I think it should be fine if you only have one ARCnet card
	* installed.
	*
	* If no ARCnet cards are installed, this delay never happens anyway and thus
	* the option has no effect.
	*/
	#undef FAST_PROBE


	/* Internal function declarations */
	static int com90xx_found(int ioaddr, int airq, u_long shmem, void __iomem *);
	static void com90xx_command(struct net_device *dev, int command);
	static int com90xx_status(struct net_device *dev);
	static void com90xx_setmask(struct net_device *dev, int mask);
	static int com90xx_reset(struct net_device *dev, int really_reset);
	static void com90xx_copy_to_card(struct net_device *dev, int bufnum, int offset,
	void *buf, int count);
	static void com90xx_copy_from_card(struct net_device *dev, int bufnum, int offset,
	void *buf, int count);

	/* Known ARCnet cards */

	static struct net_device *cards[16];
	static int numcards;

	/* Handy defines for ARCnet specific stuff */

	/* The number of low I/O ports used by the card */
	#define ARCNET_TOTAL_SIZE 16

	/* Amount of I/O memory used by the card */
	#define BUFFER_SIZE (512)
	#define MIRROR_SIZE (BUFFER_SIZE*4)

	/* COM 9026 controller chip --> ARCnet register addresses */
	#define _INTMASK (ioaddr+0) /* writable */
	#define _STATUS (ioaddr+0) /* readable */
	#define _COMMAND (ioaddr+1) /* writable, returns random vals on read (?) */
	#define _CONFIG (ioaddr+2) /* Configuration register */
	#define _RESET (ioaddr+8) /* software reset (on read) */
	#define _MEMDATA (ioaddr+12) /* Data port for IO-mapped memory */
	#define _ADDR_HI (ioaddr+15) /* Control registers for said */
	#define _ADDR_LO (ioaddr+14)

	#undef ASTATUS
	#undef ACOMMAND
	#undef AINTMASK

	#define ASTATUS() inb(_STATUS)
	#define ACOMMAND(cmd) outb((cmd),_COMMAND)
	#define AINTMASK(msk) outb((msk),_INTMASK)


	static int com90xx_skip_probe __initdata = 0;

	/* Module parameters */

	static int io; /* use the insmod io= irq= shmem= options */
	static int irq;
	static int shmem;
	static char device[9]; /* use eg. device=arc1 to change name */

	module_param(io, int, 0);
	module_param(irq, int, 0);
	module_param(shmem, int, 0);
	module_param_string(device, device, sizeof(device), 0);

	static void __init com90xx_probe(void)
	{
	int count, status, ioaddr, numprint, airq, openparen = 0;
	unsigned long airqmask;
	int ports[(0x3f0 - 0x200) / 16 + 1] =
	{0};
	unsigned long *shmems;
	void __iomem **iomem;
	int numports, numshmems, *port;
	u_long *p;
	int index;

	if (!io && !irq && !shmem && !*device && com90xx_skip_probe)
	return;

	shmems = kzalloc(((0x10000-0xa0000) / 0x800) * sizeof(unsigned long),
	GFP_KERNEL);
	if (!shmems)
	return;
	iomem = kzalloc(((0x10000-0xa0000) / 0x800) * sizeof(void __iomem *),
	GFP_KERNEL);
	if (!iomem) {
	kfree(shmems);
	return;
	}

	BUGLVL(D_NORMAL) printk(VERSION);

	/* set up the arrays where we'll store the possible probe addresses */
	numports = numshmems = 0;
	if (io)
	ports[numports++] = io;
	else
	for (count = 0x200; count <= 0x3f0; count += 16)
	ports[numports++] = count;
	if (shmem)
	shmems[numshmems++] = shmem;
	else
	for (count = 0xA0000; count <= 0xFF800; count += 2048)
	shmems[numshmems++] = count;

	/* Stage 1: abandon any reserved ports, or ones with status==0xFF
	* (empty), and reset any others by reading the reset port.
	*/
	numprint = -1;
	for (port = &ports[0]; port - ports < numports; port++) {
	numprint++;
	numprint %= 8;
	if (!numprint) {
	BUGMSG2(D_INIT, "\n");
	BUGMSG2(D_INIT, "S1: ");
	}
	BUGMSG2(D_INIT, "%Xh ", *port);

	ioaddr = *port;

	if (!request_region(*port, ARCNET_TOTAL_SIZE, "arcnet (90xx)")) {
	BUGMSG2(D_INIT_REASONS, "(request_region)\n");
	BUGMSG2(D_INIT_REASONS, "S1: ");
	BUGLVL(D_INIT_REASONS) numprint = 0;
	*port-- = ports[--numports];
	continue;
	}
	if (ASTATUS() == 0xFF) {
	BUGMSG2(D_INIT_REASONS, "(empty)\n");
	BUGMSG2(D_INIT_REASONS, "S1: ");
	BUGLVL(D_INIT_REASONS) numprint = 0;
	release_region(*port, ARCNET_TOTAL_SIZE);
	*port-- = ports[--numports];
	continue;
	}
	inb(_RESET); /* begin resetting card */

	BUGMSG2(D_INIT_REASONS, "\n");
	BUGMSG2(D_INIT_REASONS, "S1: ");
	BUGLVL(D_INIT_REASONS) numprint = 0;
	}
	BUGMSG2(D_INIT, "\n");

	if (!numports) {
	BUGMSG2(D_NORMAL, "S1: No ARCnet cards found.\n");
	kfree(shmems);
	kfree(iomem);
	return;
	}
	/* Stage 2: we have now reset any possible ARCnet cards, so we can't
	* do anything until they finish. If D_INIT, print the list of
	* cards that are left.
	*/
	numprint = -1;
	for (port = &ports[0]; port < ports + numports; port++) {
	numprint++;
	numprint %= 8;
	if (!numprint) {
	BUGMSG2(D_INIT, "\n");
	BUGMSG2(D_INIT, "S2: ");
	}
	BUGMSG2(D_INIT, "%Xh ", *port);
	}
	BUGMSG2(D_INIT, "\n");
	mdelay(RESETtime);

	/* Stage 3: abandon any shmem addresses that don't have the signature
	* 0xD1 byte in the right place, or are read-only.
	*/
	numprint = -1;
	for (index = 0, p = &shmems[0]; index < numshmems; p++, index++) {
	void __iomem *base;

	numprint++;
	numprint %= 8;
	if (!numprint) {
	BUGMSG2(D_INIT, "\n");
	BUGMSG2(D_INIT, "S3: ");
	}
	BUGMSG2(D_INIT, "%lXh ", *p);

	if (!request_mem_region(*p, MIRROR_SIZE, "arcnet (90xx)")) {
	BUGMSG2(D_INIT_REASONS, "(request_mem_region)\n");
	BUGMSG2(D_INIT_REASONS, "Stage 3: ");
	BUGLVL(D_INIT_REASONS) numprint = 0;
	goto out;
	}
	base = ioremap(*p, MIRROR_SIZE);
	if (!base) {
	BUGMSG2(D_INIT_REASONS, "(ioremap)\n");
	BUGMSG2(D_INIT_REASONS, "Stage 3: ");
	BUGLVL(D_INIT_REASONS) numprint = 0;
	goto out1;
	}
	if (readb(base) != TESTvalue) {
	BUGMSG2(D_INIT_REASONS, "(%02Xh != %02Xh)\n",
	readb(base), TESTvalue);
	BUGMSG2(D_INIT_REASONS, "S3: ");
	BUGLVL(D_INIT_REASONS) numprint = 0;
	goto out2;
	}
	/* By writing 0x42 to the TESTvalue location, we also make
	* sure no "mirror" shmem areas show up - if they occur
	* in another pass through this loop, they will be discarded
	* because *cptr != TESTvalue.
	*/
	writeb(0x42, base);
	if (readb(base) != 0x42) {
	BUGMSG2(D_INIT_REASONS, "(read only)\n");
	BUGMSG2(D_INIT_REASONS, "S3: ");
	goto out2;
	}
	BUGMSG2(D_INIT_REASONS, "\n");
	BUGMSG2(D_INIT_REASONS, "S3: ");
	BUGLVL(D_INIT_REASONS) numprint = 0;
	iomem[index] = base;
	continue;
	out2:
	iounmap(base);
	out1:
	release_mem_region(*p, MIRROR_SIZE);
	out:
	*p-- = shmems[--numshmems];
	index--;
	}
	BUGMSG2(D_INIT, "\n");

	if (!numshmems) {
	BUGMSG2(D_NORMAL, "S3: No ARCnet cards found.\n");
	for (port = &ports[0]; port < ports + numports; port++)
	release_region(*port, ARCNET_TOTAL_SIZE);
	kfree(shmems);
	kfree(iomem);
	return;
	}
	/* Stage 4: something of a dummy, to report the shmems that are
	* still possible after stage 3.
	*/
	numprint = -1;
	for (p = &shmems[0]; p < shmems + numshmems; p++) {
	numprint++;
	numprint %= 8;
	if (!numprint) {
	BUGMSG2(D_INIT, "\n");
	BUGMSG2(D_INIT, "S4: ");
	}
	BUGMSG2(D_INIT, "%lXh ", *p);
	}
	BUGMSG2(D_INIT, "\n");

	/* Stage 5: for any ports that have the correct status, can disable
	* the RESET flag, and (if no irq is given) generate an autoirq,
	* register an ARCnet device.
	*
	* Currently, we can only register one device per probe, so quit
	* after the first one is found.
	*/
	numprint = -1;
	for (port = &ports[0]; port < ports + numports; port++) {
	int found = 0;
	numprint++;
	numprint %= 8;
	if (!numprint) {
	BUGMSG2(D_INIT, "\n");
	BUGMSG2(D_INIT, "S5: ");
	}
	BUGMSG2(D_INIT, "%Xh ", *port);

	ioaddr = *port;
	status = ASTATUS();

	if ((status & 0x9D)
	!= (NORXflag \| RECONflag \| TXFREEflag \| RESETflag)) {
	BUGMSG2(D_INIT_REASONS, "(status=%Xh)\n", status);
	BUGMSG2(D_INIT_REASONS, "S5: ");
	BUGLVL(D_INIT_REASONS) numprint = 0;
	release_region(*port, ARCNET_TOTAL_SIZE);
	*port-- = ports[--numports];
	continue;
	}
	ACOMMAND(CFLAGScmd \| RESETclear \| CONFIGclear);
	status = ASTATUS();
	if (status & RESETflag) {
	BUGMSG2(D_INIT_REASONS, " (eternal reset, status=%Xh)\n",
	status);
	BUGMSG2(D_INIT_REASONS, "S5: ");
	BUGLVL(D_INIT_REASONS) numprint = 0;
	release_region(*port, ARCNET_TOTAL_SIZE);
	*port-- = ports[--numports];
	continue;
	}
	/* skip this completely if an IRQ was given, because maybe
	* we're on a machine that locks during autoirq!
	*/
	if (!irq) {
	/* if we do this, we're sure to get an IRQ since the
	* card has just reset and the NORXflag is on until
	* we tell it to start receiving.
	*/
	airqmask = probe_irq_on();
	AINTMASK(NORXflag);
	udelay(1);
	AINTMASK(0);
	airq = probe_irq_off(airqmask);

	if (airq <= 0) {
	BUGMSG2(D_INIT_REASONS, "(airq=%d)\n", airq);
	BUGMSG2(D_INIT_REASONS, "S5: ");
	BUGLVL(D_INIT_REASONS) numprint = 0;
	release_region(*port, ARCNET_TOTAL_SIZE);
	*port-- = ports[--numports];
	continue;
	}
	} else {
	airq = irq;
	}

	BUGMSG2(D_INIT, "(%d,", airq);
	openparen = 1;

	/* Everything seems okay. But which shmem, if any, puts
	* back its signature byte when the card is reset?
	*
	* If there are multiple cards installed, there might be
	* multiple shmems still in the list.
	*/
	#ifdef FAST_PROBE
	if (numports > 1 \|\| numshmems > 1) {
	inb(_RESET);
	mdelay(RESETtime);
	} else {
	/* just one shmem and port, assume they match */
	writeb(TESTvalue, iomem[0]);
	}
	#else
	inb(_RESET);
	mdelay(RESETtime);
	#endif

	for (index = 0; index < numshmems; index++) {
	u_long ptr = shmems[index];
	void __iomem *base = iomem[index];

	if (readb(base) == TESTvalue) { /* found one */
	BUGMSG2(D_INIT, "%lXh)\n", *p);
	openparen = 0;

	/* register the card */
	if (com90xx_found(*port, airq, ptr, base) == 0)
	found = 1;
	numprint = -1;

	/* remove shmem from the list */
	shmems[index] = shmems[--numshmems];
	iomem[index] = iomem[numshmems];
	break; /* go to the next I/O port */
	} else {
	BUGMSG2(D_INIT_REASONS, "%Xh-", readb(base));
	}
	}

	if (openparen) {
	BUGLVL(D_INIT) printk("no matching shmem)\n");
	BUGLVL(D_INIT_REASONS) printk("S5: ");
	BUGLVL(D_INIT_REASONS) numprint = 0;
	}
	if (!found)
	release_region(*port, ARCNET_TOTAL_SIZE);
	*port-- = ports[--numports];
	}

	BUGLVL(D_INIT_REASONS) printk("\n");

	/* Now put back TESTvalue on all leftover shmems. */
	for (index = 0; index < numshmems; index++) {
	writeb(TESTvalue, iomem[index]);
	iounmap(iomem[index]);
	release_mem_region(shmems[index], MIRROR_SIZE);
	}
	kfree(shmems);
	kfree(iomem);
	}

	static int check_mirror(unsigned long addr, size_t size)
	{
	void __iomem *p;
	int res = -1;

	if (!request_mem_region(addr, size, "arcnet (90xx)"))
	return -1;

	p = ioremap(addr, size);
	if (p) {
	if (readb(p) == TESTvalue)
	res = 1;
	else
	res = 0;
	iounmap(p);
	}

	release_mem_region(addr, size);
	return res;
	}

	/* Set up the struct net_device associated with this card. Called after
	* probing succeeds.
	*/
	static int __init com90xx_found(int ioaddr, int airq, u_long shmem, void __iomem *p)
	{
	struct net_device *dev = NULL;
	struct arcnet_local *lp;
	u_long first_mirror, last_mirror;
	int mirror_size;

	/* allocate struct net_device */
	dev = alloc_arcdev(device);
	if (!dev) {
	BUGMSG2(D_NORMAL, "com90xx: Can't allocate device!\n");
	iounmap(p);
	release_mem_region(shmem, MIRROR_SIZE);
	return -ENOMEM;
	}
	lp = dev->priv;
	/* find the real shared memory start/end points, including mirrors */

	/* guess the actual size of one "memory mirror" - the number of
	* bytes between copies of the shared memory. On most cards, it's
	* 2k (or there are no mirrors at all) but on some, it's 4k.
	*/
	mirror_size = MIRROR_SIZE;
	if (readb(p) == TESTvalue &&
	check_mirror(shmem - MIRROR_SIZE, MIRROR_SIZE) == 0 &&
	check_mirror(shmem - 2 * MIRROR_SIZE, MIRROR_SIZE) == 1)
	mirror_size = 2 * MIRROR_SIZE;

	first_mirror = shmem - mirror_size;
	while (check_mirror(first_mirror, mirror_size) == 1)
	first_mirror -= mirror_size;
	first_mirror += mirror_size;

	last_mirror = shmem + mirror_size;
	while (check_mirror(last_mirror, mirror_size) == 1)
	last_mirror += mirror_size;
	last_mirror -= mirror_size;

	dev->mem_start = first_mirror;
	dev->mem_end = last_mirror + MIRROR_SIZE - 1;

	iounmap(p);
	release_mem_region(shmem, MIRROR_SIZE);

	if (!request_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1, "arcnet (90xx)"))
	goto err_free_dev;

	/* reserve the irq */
	if (request_irq(airq, &arcnet_interrupt, 0, "arcnet (90xx)", dev)) {
	BUGMSG(D_NORMAL, "Can't get IRQ %d!\n", airq);
	goto err_release_mem;
	}
	dev->irq = airq;

	/* Initialize the rest of the device structure. */
	lp->card_name = "COM90xx";
	lp->hw.command = com90xx_command;
	lp->hw.status = com90xx_status;
	lp->hw.intmask = com90xx_setmask;
	lp->hw.reset = com90xx_reset;
	lp->hw.owner = THIS_MODULE;
	lp->hw.copy_to_card = com90xx_copy_to_card;
	lp->hw.copy_from_card = com90xx_copy_from_card;
	lp->mem_start = ioremap(dev->mem_start, dev->mem_end - dev->mem_start + 1);
	if (!lp->mem_start) {
	BUGMSG(D_NORMAL, "Can't remap device memory!\n");
	goto err_free_irq;
	}

	/* get and check the station ID from offset 1 in shmem */
	dev->dev_addr[0] = readb(lp->mem_start + 1);

	dev->base_addr = ioaddr;

	BUGMSG(D_NORMAL, "COM90xx station %02Xh found at %03lXh, IRQ %d, "
	"ShMem %lXh (%ld*%xh).\n",
	dev->dev_addr[0],
	dev->base_addr, dev->irq, dev->mem_start,
	(dev->mem_end - dev->mem_start + 1) / mirror_size, mirror_size);

	if (register_netdev(dev))
	goto err_unmap;

	cards[numcards++] = dev;
	return 0;

	err_unmap:
	iounmap(lp->mem_start);
	err_free_irq:
	free_irq(dev->irq, dev);
	err_release_mem:
	release_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1);
	err_free_dev:
	free_netdev(dev);
	return -EIO;
	}


	static void com90xx_command(struct net_device *dev, int cmd)
	{
	short ioaddr = dev->base_addr;

	ACOMMAND(cmd);
	}


	static int com90xx_status(struct net_device *dev)
	{
	short ioaddr = dev->base_addr;

	return ASTATUS();
	}


	static void com90xx_setmask(struct net_device *dev, int mask)
	{
	short ioaddr = dev->base_addr;

	AINTMASK(mask);
	}


	/*
	* Do a hardware reset on the card, and set up necessary registers.
	*
	* This should be called as little as possible, because it disrupts the
	* token on the network (causes a RECON) and requires a significant delay.
	*
	* However, it does make sure the card is in a defined state.
	*/
	int com90xx_reset(struct net_device *dev, int really_reset)
	{
	struct arcnet_local *lp = dev->priv;
	short ioaddr = dev->base_addr;

	BUGMSG(D_INIT, "Resetting (status=%02Xh)\n", ASTATUS());

	if (really_reset) {
	/* reset the card */
	inb(_RESET);
	mdelay(RESETtime);
	}
	ACOMMAND(CFLAGScmd \| RESETclear); /* clear flags & end reset */
	ACOMMAND(CFLAGScmd \| CONFIGclear);

	/* don't do this until we verify that it doesn't hurt older cards! */
	/* outb(inb(_CONFIG) \| ENABLE16flag, _CONFIG); */

	/* verify that the ARCnet signature byte is present */
	if (readb(lp->mem_start) != TESTvalue) {
	if (really_reset)
	BUGMSG(D_NORMAL, "reset failed: TESTvalue not present.\n");
	return 1;
	}
	/* enable extended (512-byte) packets */
	ACOMMAND(CONFIGcmd \| EXTconf);

	/* clean out all the memory to make debugging make more sense :) */
	BUGLVL(D_DURING)
	memset_io(lp->mem_start, 0x42, 2048);

	/* done! return success. */
	return 0;
	}

	static void com90xx_copy_to_card(struct net_device *dev, int bufnum, int offset,
	void *buf, int count)
	{
	struct arcnet_local *lp = dev->priv;
	void __iomem memaddr = lp->mem_start + bufnum 512 + offset;
	TIME("memcpy_toio", count, memcpy_toio(memaddr, buf, count));
	}


	static void com90xx_copy_from_card(struct net_device *dev, int bufnum, int offset,
	void *buf, int count)
	{
	struct arcnet_local *lp = dev->priv;
	void __iomem memaddr = lp->mem_start + bufnum 512 + offset;
	TIME("memcpy_fromio", count, memcpy_fromio(buf, memaddr, count));
	}


	MODULE_LICENSE("GPL");

	static int __init com90xx_init(void)
	{
	if (irq == 2)
	irq = 9;
	com90xx_probe();
	if (!numcards)
	return -EIO;
	return 0;
	}

	static void __exit com90xx_exit(void)
	{
	struct net_device *dev;
	struct arcnet_local *lp;
	int count;

	for (count = 0; count < numcards; count++) {
	dev = cards[count];
	lp = dev->priv;

	unregister_netdev(dev);
	free_irq(dev->irq, dev);
	iounmap(lp->mem_start);
	release_region(dev->base_addr, ARCNET_TOTAL_SIZE);
	release_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1);
	free_netdev(dev);
	}
	}

	module_init(com90xx_init);
	module_exit(com90xx_exit);

	#ifndef MODULE
	static int __init com90xx_setup(char *s)
	{
	int ints[8];

	s = get_options(s, 8, ints);
	if (!ints[0] && !*s) {
	printk("com90xx: Disabled.\n");
	return 1;
	}

	switch (ints[0]) {
	default: /* ERROR */
	printk("com90xx: Too many arguments.\n");
	case 3: /* Mem address */
	shmem = ints[3];
	case 2: /* IRQ */
	irq = ints[2];
	case 1: /* IO address */
	io = ints[1];
	}

	if (*s)
	snprintf(device, sizeof(device), "%s", s);

	return 1;
	}

	__setup("com90xx=", com90xx_setup);
	#endif