/*======================================================================

    Aironet driver for 4500 and 4800 series cards

    The contents of this file are subject to the Mozilla Public
    License Version 1.0 (the "License"); you may not use this file
    except in compliance with the License. You may obtain a copy of
    the License at http://www.mozilla.org/MPL/

    Software distributed under the License is distributed on an "AS
    IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
    implied. See the License for the specific language governing
    rights and limitations under the License.

    This code was developed by Benjamin Reed <breed@almaden.ibm.com>
    including portions of which come from the Aironet PC4500
    Developer's Reference Manual and used with permission.  Copyright
    (C) 1999 Benjamin Reed.  All Rights Reserved.  Permission to use
    code in the Developer's manual was granted for this driver by
    Aironet.

    In addition this module was derived from dummy_cs.
    The initial developer of dummy_cs is David A. Hinds
    <dahinds@users.sourceforge.net>.  Portions created by David A. Hinds
    are Copyright (C) 1999 David A. Hinds.  All Rights Reserved.    
    
======================================================================*/

#include <linux/config.h>
#ifndef __KERNEL__
#define __KERNEL__
#endif

#ifndef MODULE
#define MODULE
#endif

#ifdef CONFIG_MODVERSIONS
#define MODVERSIONS
#include <linux/modversions.h>
#endif   

#include <linux/kernel.h>
#include <linux/module.h>

#include <linux/sched.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/timer.h>
#include <linux/netdevice.h>
#include <asm/io.h>
#include <asm/system.h>

#include <pcmcia/version.h>
#include <pcmcia/cs_types.h>
#include <pcmcia/cs.h>
#include <pcmcia/cistpl.h>
#include <pcmcia/cisreg.h>
#include <pcmcia/ds.h>

/*
   All the PCMCIA modules use PCMCIA_DEBUG to control debugging.  If
   you do not define PCMCIA_DEBUG at all, all the debug code will be
   left out.  If you compile with PCMCIA_DEBUG=0, the debug code will
   be present but disabled -- but it can then be enabled for specific
   modules at load time with a 'pc_debug=#' option to insmod.
*/
#ifdef PCMCIA_DEBUG
static int pc_debug = PCMCIA_DEBUG;
MODULE_PARM(pc_debug, "i");
#define DEBUG(n, args...) if (pc_debug>(n)) printk(KERN_DEBUG args);
static char *version =
"airo_cs.c 1.0 2001/02/08 (Benjamin Reed)";
#else
#define DEBUG(n, args...)
#endif

/*====================================================================*/

/* Parameters that can be set with 'insmod' */

/* The old way: bit map of interrupts to choose from */
/* This means pick from 15, 14, 12, 11, 10, 9, 7, 5, 4, and 3 */
static u_int irq_mask = 0xdeb8;
/* Newer, simpler way of listing specific interrupts */
static int irq_list[4] = { -1 };

MODULE_AUTHOR("Benjamin Reed");
MODULE_DESCRIPTION("Support for Cisco/Aironet 802.11 wireless ethernet \
                   cards.  This is the module that links the PCMCIA card \
		   with the airo module.");
MODULE_LICENSE("MPL");
MODULE_SUPPORTED_DEVICE("Aironet 4500, 4800 and Cisco 340 PCMCIA cards");
MODULE_PARM(irq_mask, "i");
MODULE_PARM(irq_list, "1-4i");

/*====================================================================*/

/*
   The event() function is this driver's Card Services event handler.
   It will be called by Card Services when an appropriate card status
   event is received.  The config() and release() entry points are
   used to configure or release a socket, in response to card
   insertion and ejection events.  They are invoked from the airo_cs
   event handler. 
*/

struct net_device *init_airo_card( int, int );
void stop_airo_card( struct net_device *, int );
int reset_airo_card( struct net_device * );

static void airo_config(dev_link_t *link);
static void airo_release(u_long arg);
static int airo_event(event_t event, int priority,
		       event_callback_args_t *args);

/*
   The attach() and detach() entry points are used to create and destroy
   "instances" of the driver, where each instance represents everything
   needed to manage one actual PCMCIA card.
*/

static dev_link_t *airo_attach(void);
static void airo_detach(dev_link_t *);

/*
   You'll also need to prototype all the functions that will actually
   be used to talk to your device.  See 'pcmem_cs' for a good example
   of a fully self-sufficient driver; the other drivers rely more or
   less on other parts of the kernel.
*/

/*
   The dev_info variable is the "key" that is used to match up this
   device driver with appropriate cards, through the card configuration
   database.
*/

static dev_info_t dev_info = "airo_cs";

/*
   A linked list of "instances" of the  aironet device.  Each actual
   PCMCIA card corresponds to one device instance, and is described
   by one dev_link_t structure (defined in ds.h).

   You may not want to use a linked list for this -- for example, the
   memory card driver uses an array of dev_link_t pointers, where minor
   device numbers are used to derive the corresponding array index.
*/

static dev_link_t *dev_list = NULL;

/*
   A dev_link_t structure has fields for most things that are needed
   to keep track of a socket, but there will usually be some device
   specific information that also needs to be kept track of.  The
   'priv' pointer in a dev_link_t structure can be used to point to
   a device-specific private data structure, like this.

   A driver needs to provide a dev_node_t structure for each device
   on a card.  In some cases, there is only one device per card (for
   example, ethernet cards, modems).  In other cases, there may be
   many actual or logical devices (SCSI adapters, memory cards with
   multiple partitions).  The dev_node_t structures need to be kept
   in a linked list starting at the 'dev' field of a dev_link_t
   structure.  We allocate them in the card's private data structure,
   because they generally shouldn't be allocated dynamically.

   In this case, we also provide a flag to indicate if a device is
   "stopped" due to a power management event, or card ejection.  The
   device IO routines can use a flag like this to throttle IO to a
   card that is not ready to accept it.
*/
   
typedef struct local_info_t {
	dev_node_t	node;
	struct net_device *eth_dev;
} local_info_t;

/*====================================================================*/

static void cs_error(client_handle_t handle, int func, int ret)
{
	error_info_t err = { func, ret };
	CardServices(ReportError, handle, &err);
}

/*======================================================================
  
  This bit of code is used to avoid unregistering network devices
  at inappropriate times.  2.2 and later kernels are fairly picky
  about when this can happen.
  
  ======================================================================*/

static void flush_stale_links(void)
{
	dev_link_t *link, *next;
	for (link = dev_list; link; link = next) {
		next = link->next;
		if (link->state & DEV_STALE_LINK)
			airo_detach(link);
	}
}
 
/*======================================================================
  
  airo_attach() creates an "instance" of the driver, allocating
  local data structures for one device.  The device is registered
  with Card Services.
  
  The dev_link structure is initialized, but we don't actually
  configure the card at this point -- we wait until we receive a
  card insertion event.
  
  ======================================================================*/

static dev_link_t *airo_attach(void)
{
	client_reg_t client_reg;
	dev_link_t *link;
	local_info_t *local;
	int ret, i;
	
	DEBUG(0, "airo_attach()\n");
	flush_stale_links();
	
	/* Initialize the dev_link_t structure */
	link = kmalloc(sizeof(struct dev_link_t), GFP_KERNEL);
	memset(link, 0, sizeof(struct dev_link_t));
	init_timer(&link->release);
	link->release.function = &airo_release;
	link->release.data = (u_long)link;
	
	/* Interrupt setup */
	link->irq.Attributes = IRQ_TYPE_EXCLUSIVE;
	link->irq.IRQInfo1 = IRQ_INFO2_VALID|IRQ_LEVEL_ID;
	if (irq_list[0] == -1)
		link->irq.IRQInfo2 = irq_mask;
	else
		for (i = 0; i < 4; i++)
			link->irq.IRQInfo2 |= 1 << irq_list[i];
	link->irq.Handler = NULL;
	
	/*
	  General socket configuration defaults can go here.  In this
	  client, we assume very little, and rely on the CIS for almost
	  everything.  In most clients, many details (i.e., number, sizes,
	  and attributes of IO windows) are fixed by the nature of the
	  device, and can be hard-wired here.
	*/
	link->conf.Attributes = 0;
	link->conf.Vcc = 50;
	link->conf.IntType = INT_MEMORY_AND_IO;
	
	/* Allocate space for private device-specific data */
	local = kmalloc(sizeof(local_info_t), GFP_KERNEL);
	memset(local, 0, sizeof(local_info_t));
	link->priv = local;
	
	/* Register with Card Services */
	link->next = dev_list;
	dev_list = link;
	client_reg.dev_info = &dev_info;
	client_reg.Attributes = INFO_IO_CLIENT | INFO_CARD_SHARE;
	client_reg.EventMask =
		CS_EVENT_CARD_INSERTION | CS_EVENT_CARD_REMOVAL |
		CS_EVENT_RESET_PHYSICAL | CS_EVENT_CARD_RESET |
		CS_EVENT_PM_SUSPEND | CS_EVENT_PM_RESUME;
	client_reg.event_handler = &airo_event;
	client_reg.Version = 0x0210;
	client_reg.event_callback_args.client_data = link;
	ret = CardServices(RegisterClient, &link->handle, &client_reg);
	if (ret != 0) {
		cs_error(link->handle, RegisterClient, ret);
		airo_detach(link);
		return NULL;
	}
	
	return link;
} /* airo_attach */

/*======================================================================
  
  This deletes a driver "instance".  The device is de-registered
  with Card Services.  If it has been released, all local data
  structures are freed.  Otherwise, the structures will be freed
  when the device is released.
  
  ======================================================================*/

static void airo_detach(dev_link_t *link)
{
	dev_link_t **linkp;
	
	DEBUG(0, "airo_detach(0x%p)\n", link);
	
	/* Locate device structure */
	for (linkp = &dev_list; *linkp; linkp = &(*linkp)->next)
		if (*linkp == link) break;
	if (*linkp == NULL)
		return;
	
	del_timer(&link->release);
	if ( link->state & DEV_CONFIG ) {
		airo_release( (int)link );
		if ( link->state & DEV_STALE_CONFIG ) {
			link->state |= DEV_STALE_LINK;
			return;
		}
	}
	
	if ( ((local_info_t*)link->priv)->eth_dev ) {
		stop_airo_card( ((local_info_t*)link->priv)->eth_dev, 0 );
	}
	((local_info_t*)link->priv)->eth_dev = 0;   
	
	/* Break the link with Card Services */
	if (link->handle)
		CardServices(DeregisterClient, link->handle);
	
	
	
	/* Unlink device structure, free pieces */
	*linkp = link->next;
	if (link->priv) {
		kfree(link->priv);
	}
	kfree(link);
	
} /* airo_detach */

/*======================================================================
  
  airo_config() is scheduled to run after a CARD_INSERTION event
  is received, to configure the PCMCIA socket, and to make the
  device available to the system.
  
  ======================================================================*/

#define CS_CHECK(fn, args...) \
while ((last_ret=CardServices(last_fn=(fn),args))!=0) goto cs_failed

#define CFG_CHECK(fn, args...) \
if (CardServices(fn, args) != 0) goto next_entry

static void airo_config(dev_link_t *link)
{
	client_handle_t handle;
	tuple_t tuple;
	cisparse_t parse;
	local_info_t *dev;
	int last_fn, last_ret;
	u_char buf[64];
	win_req_t req;
	memreq_t map;
	cistpl_cftable_entry_t dflt = { 0 };
	
	handle = link->handle;
	dev = link->priv;

	DEBUG(0, "airo_config(0x%p)\n", link);
	
	/*
	  This reads the card's CONFIG tuple to find its configuration
	  registers.
	*/
	tuple.DesiredTuple = CISTPL_CONFIG;
	tuple.Attributes = 0;
	tuple.TupleData = buf;
	tuple.TupleDataMax = sizeof(buf);
	tuple.TupleOffset = 0;
	CS_CHECK(GetFirstTuple, handle, &tuple);
	CS_CHECK(GetTupleData, handle, &tuple);
	CS_CHECK(ParseTuple, handle, &tuple, &parse);
	link->conf.ConfigBase = parse.config.base;
	link->conf.Present = parse.config.rmask[0];
	
	/* Configure card */
	link->state |= DEV_CONFIG;
	
	/*
	  In this loop, we scan the CIS for configuration table entries,
	  each of which describes a valid card configuration, including
	  voltage, IO window, memory window, and interrupt settings.
	  
	  We make no assumptions about the card to be configured: we use
	  just the information available in the CIS.  In an ideal world,
	  this would work for any PCMCIA card, but it requires a complete
	  and accurate CIS.  In practice, a driver usually "knows" most of
	  these things without consulting the CIS, and most client drivers
	  will only use the CIS to fill in implementation-defined details.
	*/
	tuple.DesiredTuple = CISTPL_CFTABLE_ENTRY;
	CS_CHECK(GetFirstTuple, handle, &tuple);
	while (1) {
		cistpl_cftable_entry_t *cfg = &(parse.cftable_entry);
		CFG_CHECK(GetTupleData, handle, &tuple);
		CFG_CHECK(ParseTuple, handle, &tuple, &parse);
		
		if (cfg->flags & CISTPL_CFTABLE_DEFAULT) dflt = *cfg;
		if (cfg->index == 0) goto next_entry;
		link->conf.ConfigIndex = cfg->index;
		
		/* Does this card need audio output? */
		if (cfg->flags & CISTPL_CFTABLE_AUDIO) {
			link->conf.Attributes |= CONF_ENABLE_SPKR;
			link->conf.Status = CCSR_AUDIO_ENA;
		}
		
		/* Use power settings for Vcc and Vpp if present */
		/*  Note that the CIS values need to be rescaled */
		if (cfg->vcc.present & (1<<CISTPL_POWER_VNOM))
			link->conf.Vcc = cfg->vcc.param[CISTPL_POWER_VNOM]/10000;
		else if (dflt.vcc.present & (1<<CISTPL_POWER_VNOM))
			link->conf.Vcc = dflt.vcc.param[CISTPL_POWER_VNOM]/10000;
		
		if (cfg->vpp1.present & (1<<CISTPL_POWER_VNOM))
			link->conf.Vpp1 = link->conf.Vpp2 =
				cfg->vpp1.param[CISTPL_POWER_VNOM]/10000;
		else if (dflt.vpp1.present & (1<<CISTPL_POWER_VNOM))
			link->conf.Vpp1 = link->conf.Vpp2 =
				dflt.vpp1.param[CISTPL_POWER_VNOM]/10000;
		
		/* Do we need to allocate an interrupt? */
		if (cfg->irq.IRQInfo1 || dflt.irq.IRQInfo1)
			link->conf.Attributes |= CONF_ENABLE_IRQ;
		
		/* IO window settings */
		link->io.NumPorts1 = link->io.NumPorts2 = 0;
		if ((cfg->io.nwin > 0) || (dflt.io.nwin > 0)) {
			cistpl_io_t *io = (cfg->io.nwin) ? &cfg->io : &dflt.io;
			link->io.Attributes1 = IO_DATA_PATH_WIDTH_AUTO;
			if (!(io->flags & CISTPL_IO_8BIT))
				link->io.Attributes1 = IO_DATA_PATH_WIDTH_16;
			if (!(io->flags & CISTPL_IO_16BIT))
				link->io.Attributes1 = IO_DATA_PATH_WIDTH_8;
			link->io.BasePort1 = io->win[0].base;
			link->io.NumPorts1 = io->win[0].len;
			if (io->nwin > 1) {
				link->io.Attributes2 = link->io.Attributes1;
				link->io.BasePort2 = io->win[1].base;
				link->io.NumPorts2 = io->win[1].len;
			}
		}
		
		/* This reserves IO space but doesn't actually enable it */
		CFG_CHECK(RequestIO, link->handle, &link->io); 
		
		/*
		  Now set up a common memory window, if needed.  There is room
		  in the dev_link_t structure for one memory window handle,
		  but if the base addresses need to be saved, or if multiple
		  windows are needed, the info should go in the private data
		  structure for this device.
		  
		  Note that the memory window base is a physical address, and
		  needs to be mapped to virtual space with ioremap() before it
		  is used.
		*/
		if ((cfg->mem.nwin > 0) || (dflt.mem.nwin > 0)) {
			cistpl_mem_t *mem =
				(cfg->mem.nwin) ? &cfg->mem : &dflt.mem;
			req.Attributes = WIN_DATA_WIDTH_16|WIN_MEMORY_TYPE_CM;
			req.Base = mem->win[0].host_addr;
			req.Size = mem->win[0].len;
			req.AccessSpeed = 0;
			link->win = (window_handle_t)link->handle;
			CFG_CHECK(RequestWindow, &link->win, &req);
			map.Page = 0; map.CardOffset = mem->win[0].card_addr;
			CFG_CHECK(MapMemPage, link->win, &map);
		}
		/* If we got this far, we're cool! */
		break;
		
	next_entry:
		CS_CHECK(GetNextTuple, handle, &tuple);
	}
	
    /*
      Allocate an interrupt line.  Note that this does not assign a
      handler to the interrupt, unless the 'Handler' member of the
      irq structure is initialized.
    */
	if (link->conf.Attributes & CONF_ENABLE_IRQ)
		CS_CHECK(RequestIRQ, link->handle, &link->irq);
	
	/*
	  This actually configures the PCMCIA socket -- setting up
	  the I/O windows and the interrupt mapping, and putting the
	  card and host interface into "Memory and IO" mode.
	*/
	CS_CHECK(RequestConfiguration, link->handle, &link->conf);
	((local_info_t*)link->priv)->eth_dev = 
		init_airo_card( link->irq.AssignedIRQ,
				link->io.BasePort1 );
	if (!((local_info_t*)link->priv)->eth_dev) goto cs_failed;
	
	/*
	  At this point, the dev_node_t structure(s) need to be
	  initialized and arranged in a linked list at link->dev.
	*/
	strcpy(dev->node.dev_name, ((local_info_t*)link->priv)->eth_dev->name );
	dev->node.major = dev->node.minor = 0;
	link->dev = &dev->node;
	
	/* Finally, report what we've done */
	printk(KERN_INFO "%s: index 0x%02x: Vcc %d.%d",
	       dev->node.dev_name, link->conf.ConfigIndex,
	       link->conf.Vcc/10, link->conf.Vcc%10);
	if (link->conf.Vpp1)
		printk(", Vpp %d.%d", link->conf.Vpp1/10, link->conf.Vpp1%10);
	if (link->conf.Attributes & CONF_ENABLE_IRQ)
		printk(", irq %d", link->irq.AssignedIRQ);
	if (link->io.NumPorts1)
		printk(", io 0x%04x-0x%04x", link->io.BasePort1,
		       link->io.BasePort1+link->io.NumPorts1-1);
	if (link->io.NumPorts2)
		printk(" & 0x%04x-0x%04x", link->io.BasePort2,
		       link->io.BasePort2+link->io.NumPorts2-1);
	if (link->win)
		printk(", mem 0x%06lx-0x%06lx", req.Base,
		       req.Base+req.Size-1);
	printk("\n");
	
	link->state &= ~DEV_CONFIG_PENDING;
	return;
	
 cs_failed:
	cs_error(link->handle, last_fn, last_ret);
	airo_release((u_long)link);
	link->state &= ~DEV_CONFIG_PENDING;
	
} /* airo_config */

/*======================================================================
  
  After a card is removed, airo_release() will unregister the
  device, and release the PCMCIA configuration.  If the device is
  still open, this will be postponed until it is closed.
  
  ======================================================================*/

static void airo_release(u_long arg)
{
	dev_link_t *link = (dev_link_t *)arg;
	
	DEBUG(0, "airo_release(0x%p)\n", link);
	
	/*
	  If the device is currently in use, we won't release until it
	  is actually closed, because until then, we can't be sure that
	  no one will try to access the device or its data structures.
	*/
	if (link->open) {
		DEBUG(1, "airo_cs: release postponed, '%s' still open\n",
		      link->dev->dev_name);
		link->state |= DEV_STALE_CONFIG;
		return;
	}
	
	/* Unlink the device chain */
	link->dev = NULL;
	
	/*
	  In a normal driver, additional code may be needed to release
	  other kernel data structures associated with this device. 
	*/
	
	/* Don't bother checking to see if these succeed or not */
	if (link->win)
		CardServices(ReleaseWindow, link->win);
	CardServices(ReleaseConfiguration, link->handle);
	if (link->io.NumPorts1)
		CardServices(ReleaseIO, link->handle, &link->io);
	if (link->irq.AssignedIRQ)
		CardServices(ReleaseIRQ, link->handle, &link->irq);
	link->state &= ~DEV_CONFIG;
	
} /* airo_release */

/*======================================================================
  
  The card status event handler.  Mostly, this schedules other
  stuff to run after an event is received.

  When a CARD_REMOVAL event is received, we immediately set a
  private flag to block future accesses to this device.  All the
  functions that actually access the device should check this flag
  to make sure the card is still present.
  
  ======================================================================*/

static int airo_event(event_t event, int priority,
		      event_callback_args_t *args)
{
	dev_link_t *link = args->client_data;
	local_info_t *local = link->priv;
	
	DEBUG(1, "airo_event(0x%06x)\n", event);
	
	switch (event) {
	case CS_EVENT_CARD_REMOVAL:
		link->state &= ~DEV_PRESENT;
		if (link->state & DEV_CONFIG) {
			netif_device_detach(local->eth_dev);
			mod_timer(&link->release, jiffies + HZ/20);
		}
		break;
	case CS_EVENT_CARD_INSERTION:
		link->state |= DEV_PRESENT | DEV_CONFIG_PENDING;
		airo_config(link);
		break;
	case CS_EVENT_PM_SUSPEND:
		link->state |= DEV_SUSPEND;
		/* Fall through... */
	case CS_EVENT_RESET_PHYSICAL:
		if (link->state & DEV_CONFIG) {
			netif_device_detach(local->eth_dev);
			CardServices(ReleaseConfiguration, link->handle);
		}
		break;
	case CS_EVENT_PM_RESUME:
		link->state &= ~DEV_SUSPEND;
		/* Fall through... */
	case CS_EVENT_CARD_RESET:
		if (link->state & DEV_CONFIG) {
			CardServices(RequestConfiguration, link->handle, &link->conf);
			reset_airo_card(local->eth_dev);
			netif_device_attach(local->eth_dev);
		}
		break;
	}
	return 0;
} /* airo_event */

/*====================================================================*/

int init_module(void)
{
	servinfo_t serv;
	DEBUG(0, "%s\n", version);
	CardServices(GetCardServicesInfo, &serv);
	if (serv.Revision != CS_RELEASE_CODE) {
		printk(KERN_NOTICE "airo_cs: Card Services release "
		       "does not match!\n");
		return -EINVAL;
	}
	register_pcmcia_driver(&dev_info, &airo_attach, &airo_detach);
	return 0;
}

void cleanup_module(void)
{
	DEBUG(0, "airo_cs: unloading\n");
	unregister_pcmcia_driver(&dev_info);
	while (dev_list != NULL) {
		if (dev_list->state & DEV_CONFIG)
			airo_release((u_long)dev_list);
		airo_detach(dev_list);
	}
}
