drivers/pcmcia/pcmcia_resource.c

/*
 * PCMCIA 16-bit resource management functions
 *
 * The initial developer of the original code is David A. Hinds
 * <dahinds@users.sourceforge.net>.  Portions created by David A. Hinds
 * are Copyright (C) 1999 David A. Hinds.  All Rights Reserved.
 *
 * Copyright (C) 1999	     David A. Hinds
 * Copyright (C) 2004-2005   Dominik Brodowski
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/pci.h>
#include <linux/device.h>
#include <linux/netdevice.h>
#include <linux/slab.h>

#include <asm/irq.h>

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

#include "cs_internal.h"


/* Access speed for IO windows */
static int io_speed;
module_param(io_speed, int, 0444);


static int pcmcia_adjust_io_region(struct resource *res, unsigned long start,
				   unsigned long end, struct pcmcia_socket *s)
{
	if (s->resource_ops->adjust_io_region)
		return s->resource_ops->adjust_io_region(res, start, end, s);
	return -ENOMEM;
}

static struct resource *pcmcia_find_io_region(unsigned long base, int num,
					      unsigned long align,
					      struct pcmcia_socket *s)
{
	if (s->resource_ops->find_io)
		return s->resource_ops->find_io(base, num, align, s);
	return NULL;
}

int pcmcia_validate_mem(struct pcmcia_socket *s)
{
	if (s->resource_ops->validate_mem)
		return s->resource_ops->validate_mem(s);
	/* if there is no callback, we can assume that everything is OK */
	return 0;
}

struct resource *pcmcia_find_mem_region(u_long base, u_long num, u_long align,
				 int low, struct pcmcia_socket *s)
{
	if (s->resource_ops->find_mem)
		return s->resource_ops->find_mem(base, num, align, low, s);
	return NULL;
}


/** alloc_io_space
 *
 * Special stuff for managing IO windows, because they are scarce
 */

static int alloc_io_space(struct pcmcia_socket *s, u_int attr,
			  unsigned int *base, unsigned int num, u_int lines)
{
	int i;
	unsigned int try, align;

	align = (*base) ? (lines ? 1<<lines : 0) : 1;
	if (align && (align < num)) {
		if (*base) {
			dev_dbg(&s->dev, "odd IO request: num %#x align %#x\n",
			       num, align);
			align = 0;
		} else
			while (align && (align < num))
				align <<= 1;
	}
	if (*base & ~(align-1)) {
		dev_dbg(&s->dev, "odd IO request: base %#x align %#x\n",
		       *base, align);
		align = 0;
	}
	if ((s->features & SS_CAP_STATIC_MAP) && s->io_offset) {
		*base = s->io_offset | (*base & 0x0fff);
		return 0;
	}
	/* Check for an already-allocated window that must conflict with
	 * what was asked for.  It is a hack because it does not catch all
	 * potential conflicts, just the most obvious ones.
	 */
	for (i = 0; i < MAX_IO_WIN; i++)
		if ((s->io[i].res) && *base &&
		    ((s->io[i].res->start & (align-1)) == *base))
			return 1;
	for (i = 0; i < MAX_IO_WIN; i++) {
		if (!s->io[i].res) {
			s->io[i].res = pcmcia_find_io_region(*base, num, align, s);
			if (s->io[i].res) {
				*base = s->io[i].res->start;
				s->io[i].res->flags = (s->io[i].res->flags & ~IORESOURCE_BITS) | (attr & IORESOURCE_BITS);
				s->io[i].InUse = num;
				break;
			} else
				return 1;
		} else if ((s->io[i].res->flags & IORESOURCE_BITS) != (attr & IORESOURCE_BITS))
			continue;
		/* Try to extend top of window */
		try = s->io[i].res->end + 1;
		if ((*base == 0) || (*base == try))
			if (pcmcia_adjust_io_region(s->io[i].res, s->io[i].res->start,
						    s->io[i].res->end + num, s) == 0) {
				*base = try;
				s->io[i].InUse += num;
				break;
			}
		/* Try to extend bottom of window */
		try = s->io[i].res->start - num;
		if ((*base == 0) || (*base == try))
			if (pcmcia_adjust_io_region(s->io[i].res, s->io[i].res->start - num,
						    s->io[i].res->end, s) == 0) {
				*base = try;
				s->io[i].InUse += num;
				break;
			}
	}
	return (i == MAX_IO_WIN);
} /* alloc_io_space */


static void release_io_space(struct pcmcia_socket *s, unsigned int base,
			     unsigned int num)
{
	int i;

	for (i = 0; i < MAX_IO_WIN; i++) {
		if (!s->io[i].res)
			continue;
		if ((s->io[i].res->start <= base) &&
		    (s->io[i].res->end >= base+num-1)) {
			s->io[i].InUse -= num;
			/* Free the window if no one else is using it */
			if (s->io[i].InUse == 0) {
				release_resource(s->io[i].res);
				kfree(s->io[i].res);
				s->io[i].res = NULL;
			}
		}
	}
} /* release_io_space */


/** pccard_access_configuration_register
 *
 * Access_configuration_register() reads and writes configuration
 * registers in attribute memory.  Memory window 0 is reserved for
 * this and the tuple reading services.
 */

int pcmcia_access_configuration_register(struct pcmcia_device *p_dev,
					 conf_reg_t *reg)
{
	struct pcmcia_socket *s;
	config_t *c;
	int addr;
	u_char val;

	if (!p_dev || !p_dev->function_config)
		return -EINVAL;

	s = p_dev->socket;

	mutex_lock(&s->ops_mutex);
	c = p_dev->function_config;

	if (!(c->state & CONFIG_LOCKED)) {
		dev_dbg(&s->dev, "Configuration isnt't locked\n");
		mutex_unlock(&s->ops_mutex);
		return -EACCES;
	}

	addr = (c->ConfigBase + reg->Offset) >> 1;
	mutex_unlock(&s->ops_mutex);

	switch (reg->Action) {
	case CS_READ:
		pcmcia_read_cis_mem(s, 1, addr, 1, &val);
		reg->Value = val;
		break;
	case CS_WRITE:
		val = reg->Value;
		pcmcia_write_cis_mem(s, 1, addr, 1, &val);
		break;
	default:
		dev_dbg(&s->dev, "Invalid conf register request\n");
		return -EINVAL;
		break;
	}
	return 0;
} /* pcmcia_access_configuration_register */
EXPORT_SYMBOL(pcmcia_access_configuration_register);


int pcmcia_map_mem_page(struct pcmcia_device *p_dev, window_handle_t wh,
			memreq_t *req)
{
	struct pcmcia_socket *s = p_dev->socket;
	int ret;

	wh--;
	if (wh >= MAX_WIN)
		return -EINVAL;
	if (req->Page != 0) {
		dev_dbg(&s->dev, "failure: requested page is zero\n");
		return -EINVAL;
	}
	mutex_lock(&s->ops_mutex);
	s->win[wh].card_start = req->CardOffset;
	ret = s->ops->set_mem_map(s, &s->win[wh]);
	if (ret)
		dev_warn(&s->dev, "failed to set_mem_map\n");
	mutex_unlock(&s->ops_mutex);
	return ret;
} /* pcmcia_map_mem_page */
EXPORT_SYMBOL(pcmcia_map_mem_page);


/** pcmcia_modify_configuration
 *
 * Modify a locked socket configuration
 */
int pcmcia_modify_configuration(struct pcmcia_device *p_dev,
				modconf_t *mod)
{
	struct pcmcia_socket *s;
	config_t *c;
	int ret;

	s = p_dev->socket;

	mutex_lock(&s->ops_mutex);
	c = p_dev->function_config;

	if (!(s->state & SOCKET_PRESENT)) {
		dev_dbg(&s->dev, "No card present\n");
		ret = -ENODEV;
		goto unlock;
	}
	if (!(c->state & CONFIG_LOCKED)) {
		dev_dbg(&s->dev, "Configuration isnt't locked\n");
		ret = -EACCES;
		goto unlock;
	}

	if (mod->Attributes & (CONF_IRQ_CHANGE_VALID | CONF_VCC_CHANGE_VALID)) {
		dev_dbg(&s->dev,
			"changing Vcc or IRQ is not allowed at this time\n");
		ret = -EINVAL;
		goto unlock;
	}

	/* We only allow changing Vpp1 and Vpp2 to the same value */
	if ((mod->Attributes & CONF_VPP1_CHANGE_VALID) &&
	    (mod->Attributes & CONF_VPP2_CHANGE_VALID)) {
		if (mod->Vpp1 != mod->Vpp2) {
			dev_dbg(&s->dev, "Vpp1 and Vpp2 must be the same\n");
			ret = -EINVAL;
			goto unlock;
		}
		s->socket.Vpp = mod->Vpp1;
		if (s->ops->set_socket(s, &s->socket)) {
			dev_printk(KERN_WARNING, &s->dev,
				   "Unable to set VPP\n");
			ret = -EIO;
			goto unlock;
		}
	} else if ((mod->Attributes & CONF_VPP1_CHANGE_VALID) ||
		   (mod->Attributes & CONF_VPP2_CHANGE_VALID)) {
		dev_dbg(&s->dev, "changing Vcc is not allowed at this time\n");
		ret = -EINVAL;
		goto unlock;
	}

	if (mod->Attributes & CONF_IO_CHANGE_WIDTH) {
		pccard_io_map io_off = { 0, 0, 0, 0, 1 };
		pccard_io_map io_on;
		int i;

		io_on.speed = io_speed;
		for (i = 0; i < MAX_IO_WIN; i++) {
			if (!s->io[i].res)
				continue;
			io_off.map = i;
			io_on.map = i;

			io_on.flags = MAP_ACTIVE | IO_DATA_PATH_WIDTH_8;
			io_on.start = s->io[i].res->start;
			io_on.stop = s->io[i].res->end;

			s->ops->set_io_map(s, &io_off);
			mdelay(40);
			s->ops->set_io_map(s, &io_on);
		}
	}
	ret = 0;
unlock:
	mutex_unlock(&s->ops_mutex);

	return ret;
} /* modify_configuration */
EXPORT_SYMBOL(pcmcia_modify_configuration);


int pcmcia_release_configuration(struct pcmcia_device *p_dev)
{
	pccard_io_map io = { 0, 0, 0, 0, 1 };
	struct pcmcia_socket *s = p_dev->socket;
	config_t *c;
	int i;

	mutex_lock(&s->ops_mutex);
	c = p_dev->function_config;
	if (p_dev->_locked) {
		p_dev->_locked = 0;
		if (--(s->lock_count) == 0) {
			s->socket.flags = SS_OUTPUT_ENA;   /* Is this correct? */
			s->socket.Vpp = 0;
			s->socket.io_irq = 0;
			s->ops->set_socket(s, &s->socket);
		}
	}
	if (c->state & CONFIG_LOCKED) {
		c->state &= ~CONFIG_LOCKED;
		if (c->state & CONFIG_IO_REQ)
			for (i = 0; i < MAX_IO_WIN; i++) {
				if (!s->io[i].res)
					continue;
				s->io[i].Config--;
				if (s->io[i].Config != 0)
					continue;
				io.map = i;
				s->ops->set_io_map(s, &io);
			}
	}
	mutex_unlock(&s->ops_mutex);

	return 0;
} /* pcmcia_release_configuration */


/** pcmcia_release_io
 *
 * Release_io() releases the I/O ranges allocated by a client.  This
 * may be invoked some time after a card ejection has already dumped
 * the actual socket configuration, so if the client is "stale", we
 * don't bother checking the port ranges against the current socket
 * values.
 */
static int pcmcia_release_io(struct pcmcia_device *p_dev, io_req_t *req)
{
	struct pcmcia_socket *s = p_dev->socket;
	int ret = -EINVAL;
	config_t *c;

	mutex_lock(&s->ops_mutex);
	c = p_dev->function_config;

	if (!p_dev->_io)
		goto out;

	p_dev->_io = 0;

	if ((c->io.BasePort1 != req->BasePort1) ||
	    (c->io.NumPorts1 != req->NumPorts1) ||
	    (c->io.BasePort2 != req->BasePort2) ||
	    (c->io.NumPorts2 != req->NumPorts2))
		goto out;

	c->state &= ~CONFIG_IO_REQ;

	release_io_space(s, req->BasePort1, req->NumPorts1);
	if (req->NumPorts2)
		release_io_space(s, req->BasePort2, req->NumPorts2);

out:
	mutex_unlock(&s->ops_mutex);

	return ret;
} /* pcmcia_release_io */


static int pcmcia_release_irq(struct pcmcia_device *p_dev, irq_req_t *req)
{
	struct pcmcia_socket *s = p_dev->socket;
	config_t *c;
	int ret = -EINVAL;

	mutex_lock(&s->ops_mutex);

	c = p_dev->function_config;

	if (!p_dev->_irq)
		goto out;

	p_dev->_irq = 0;

	if (c->state & CONFIG_LOCKED)
		goto out;

	if (c->irq.Attributes != req->Attributes) {
		dev_dbg(&s->dev, "IRQ attributes must match assigned ones\n");
		goto out;
	}
	if (s->pcmcia_irq != req->AssignedIRQ) {
		dev_dbg(&s->dev, "IRQ must match assigned one\n");
		goto out;
	}

	if (req->Handler)
		free_irq(req->AssignedIRQ, p_dev->priv);

	ret = 0;

out:
	mutex_unlock(&s->ops_mutex);

	return ret;
} /* pcmcia_release_irq */


int pcmcia_release_window(struct pcmcia_device *p_dev, window_handle_t wh)
{
	struct pcmcia_socket *s = p_dev->socket;
	pccard_mem_map *win;

	wh--;
	if (wh >= MAX_WIN)
		return -EINVAL;

	mutex_lock(&s->ops_mutex);
	win = &s->win[wh];

	if (!(p_dev->_win & CLIENT_WIN_REQ(wh))) {
		dev_dbg(&s->dev, "not releasing unknown window\n");
		mutex_unlock(&s->ops_mutex);
		return -EINVAL;
	}

	/* Shut down memory window */
	win->flags &= ~MAP_ACTIVE;
	s->ops->set_mem_map(s, win);
	s->state &= ~SOCKET_WIN_REQ(wh);

	/* Release system memory */
	if (win->res) {
		release_resource(win->res);
		kfree(win->res);
		win->res = NULL;
	}
	p_dev->_win &= ~CLIENT_WIN_REQ(wh);
	mutex_unlock(&s->ops_mutex);

	return 0;
} /* pcmcia_release_window */
EXPORT_SYMBOL(pcmcia_release_window);


int pcmcia_request_configuration(struct pcmcia_device *p_dev,
				 config_req_t *req)
{
	int i;
	u_int base;
	struct pcmcia_socket *s = p_dev->socket;
	config_t *c;
	pccard_io_map iomap;

	if (!(s->state & SOCKET_PRESENT))
		return -ENODEV;

	if (req->IntType & INT_CARDBUS) {
		dev_dbg(&s->dev, "IntType may not be INT_CARDBUS\n");
		return -EINVAL;
	}

	mutex_lock(&s->ops_mutex);
	c = p_dev->function_config;
	if (c->state & CONFIG_LOCKED) {
		mutex_unlock(&s->ops_mutex);
		dev_dbg(&s->dev, "Configuration is locked\n");
		return -EACCES;
	}

	/* Do power control.  We don't allow changes in Vcc. */
	s->socket.Vpp = req->Vpp;
	if (s->ops->set_socket(s, &s->socket)) {
		mutex_unlock(&s->ops_mutex);
		dev_printk(KERN_WARNING, &s->dev,
			   "Unable to set socket state\n");
		return -EINVAL;
	}

	/* Pick memory or I/O card, DMA mode, interrupt */
	c->IntType = req->IntType;
	c->Attributes = req->Attributes;
	if (req->IntType & INT_MEMORY_AND_IO)
		s->socket.flags |= SS_IOCARD;
	if (req->IntType & INT_ZOOMED_VIDEO)
		s->socket.flags |= SS_ZVCARD | SS_IOCARD;
	if (req->Attributes & CONF_ENABLE_DMA)
		s->socket.flags |= SS_DMA_MODE;
	if (req->Attributes & CONF_ENABLE_SPKR)
		s->socket.flags |= SS_SPKR_ENA;
	if (req->Attributes & CONF_ENABLE_IRQ)
		s->socket.io_irq = s->pcmcia_irq;
	else
		s->socket.io_irq = 0;
	s->ops->set_socket(s, &s->socket);
	s->lock_count++;
	mutex_unlock(&s->ops_mutex);

	/* Set up CIS configuration registers */
	base = c->ConfigBase = req->ConfigBase;
	c->CardValues = req->Present;
	if (req->Present & PRESENT_COPY) {
		c->Copy = req->Copy;
		pcmcia_write_cis_mem(s, 1, (base + CISREG_SCR)>>1, 1, &c->Copy);
	}
	if (req->Present & PRESENT_OPTION) {
		if (s->functions == 1) {
			c->Option = req->ConfigIndex & COR_CONFIG_MASK;
		} else {
			c->Option = req->ConfigIndex & COR_MFC_CONFIG_MASK;
			c->Option |= COR_FUNC_ENA|COR_IREQ_ENA;
			if (req->Present & PRESENT_IOBASE_0)
				c->Option |= COR_ADDR_DECODE;
		}
		if (req->Attributes & CONF_ENABLE_IRQ)
			if (!(c->irq.Attributes & IRQ_FORCED_PULSE))
				c->Option |= COR_LEVEL_REQ;
		pcmcia_write_cis_mem(s, 1, (base + CISREG_COR)>>1, 1, &c->Option);
		mdelay(40);
	}
	if (req->Present & PRESENT_STATUS) {
		c->Status = req->Status;
		pcmcia_write_cis_mem(s, 1, (base + CISREG_CCSR)>>1, 1, &c->Status);
	}
	if (req->Present & PRESENT_PIN_REPLACE) {
		c->Pin = req->Pin;
		pcmcia_write_cis_mem(s, 1, (base + CISREG_PRR)>>1, 1, &c->Pin);
	}
	if (req->Present & PRESENT_EXT_STATUS) {
		c->ExtStatus = req->ExtStatus;
		pcmcia_write_cis_mem(s, 1, (base + CISREG_ESR)>>1, 1, &c->ExtStatus);
	}
	if (req->Present & PRESENT_IOBASE_0) {
		u_char b = c->io.BasePort1 & 0xff;
		pcmcia_write_cis_mem(s, 1, (base + CISREG_IOBASE_0)>>1, 1, &b);
		b = (c->io.BasePort1 >> 8) & 0xff;
		pcmcia_write_cis_mem(s, 1, (base + CISREG_IOBASE_1)>>1, 1, &b);
	}
	if (req->Present & PRESENT_IOSIZE) {
		u_char b = c->io.NumPorts1 + c->io.NumPorts2 - 1;
		pcmcia_write_cis_mem(s, 1, (base + CISREG_IOSIZE)>>1, 1, &b);
	}

	/* Configure I/O windows */
	if (c->state & CONFIG_IO_REQ) {
		mutex_lock(&s->ops_mutex);
		iomap.speed = io_speed;
		for (i = 0; i < MAX_IO_WIN; i++)
			if (s->io[i].res) {
				iomap.map = i;
				iomap.flags = MAP_ACTIVE;
				switch (s->io[i].res->flags & IO_DATA_PATH_WIDTH) {
				case IO_DATA_PATH_WIDTH_16:
					iomap.flags |= MAP_16BIT; break;
				case IO_DATA_PATH_WIDTH_AUTO:
					iomap.flags |= MAP_AUTOSZ; break;
				default:
					break;
				}
				iomap.start = s->io[i].res->start;
				iomap.stop = s->io[i].res->end;
				s->ops->set_io_map(s, &iomap);
				s->io[i].Config++;
			}
		mutex_unlock(&s->ops_mutex);
	}

	c->state |= CONFIG_LOCKED;
	p_dev->_locked = 1;
	return 0;
} /* pcmcia_request_configuration */
EXPORT_SYMBOL(pcmcia_request_configuration);


/** pcmcia_request_io
 *
 * Request_io() reserves ranges of port addresses for a socket.
 * I have not implemented range sharing or alias addressing.
 */
int pcmcia_request_io(struct pcmcia_device *p_dev, io_req_t *req)
{
	struct pcmcia_socket *s = p_dev->socket;
	config_t *c;
	int ret = -EINVAL;

	mutex_lock(&s->ops_mutex);

	if (!(s->state & SOCKET_PRESENT)) {
		dev_dbg(&s->dev, "No card present\n");
		goto out;
	}

	if (!req)
		goto out;

	c = p_dev->function_config;
	if (c->state & CONFIG_LOCKED) {
		dev_dbg(&s->dev, "Configuration is locked\n");
		goto out;
	}
	if (c->state & CONFIG_IO_REQ) {
		dev_dbg(&s->dev, "IO already configured\n");
		goto out;
	}
	if (req->Attributes1 & (IO_SHARED | IO_FORCE_ALIAS_ACCESS)) {
		dev_dbg(&s->dev, "bad attribute setting for IO region 1\n");
		goto out;
	}
	if ((req->NumPorts2 > 0) &&
	    (req->Attributes2 & (IO_SHARED | IO_FORCE_ALIAS_ACCESS))) {
		dev_dbg(&s->dev, "bad attribute setting for IO region 2\n");
		goto out;
	}

	dev_dbg(&s->dev, "trying to allocate resource 1\n");
	ret = alloc_io_space(s, req->Attributes1, &req->BasePort1,
			     req->NumPorts1, req->IOAddrLines);
	if (ret) {
		dev_dbg(&s->dev, "allocation of resource 1 failed\n");
		goto out;
	}

	if (req->NumPorts2) {
		dev_dbg(&s->dev, "trying to allocate resource 2\n");
		ret = alloc_io_space(s, req->Attributes2, &req->BasePort2,
				     req->NumPorts2, req->IOAddrLines);
		if (ret) {
			dev_dbg(&s->dev, "allocation of resource 2 failed\n");
			release_io_space(s, req->BasePort1, req->NumPorts1);
			goto out;
		}
	}

	c->io = *req;
	c->state |= CONFIG_IO_REQ;
	p_dev->_io = 1;
	dev_dbg(&s->dev, "allocating resources succeeded: %d\n", ret);

out:
	mutex_unlock(&s->ops_mutex);

	return ret;
} /* pcmcia_request_io */
EXPORT_SYMBOL(pcmcia_request_io);


/** pcmcia_request_irq
 *
 * Request_irq() reserves an irq for this client.
 */

int pcmcia_request_irq(struct pcmcia_device *p_dev, irq_req_t *req)
{
	struct pcmcia_socket *s = p_dev->socket;
	config_t *c;
	int ret = -EINVAL, irq = p_dev->irq_v;
	int type = IRQF_SHARED;

	mutex_lock(&s->ops_mutex);

	if (!(s->state & SOCKET_PRESENT)) {
		dev_dbg(&s->dev, "No card present\n");
		goto out;
	}
	c = p_dev->function_config;
	if (c->state & CONFIG_LOCKED) {
		dev_dbg(&s->dev, "Configuration is locked\n");
		goto out;
	}

	if (!irq) {
		dev_dbg(&s->dev, "no IRQ available\n");
		goto out;
	}

	if (!(req->Attributes & IRQ_TYPE_DYNAMIC_SHARING)) {
		req->Attributes |= IRQ_TYPE_DYNAMIC_SHARING;
		dev_printk(KERN_WARNING, &p_dev->dev, "pcmcia: the driver "
			"needs updating to supported shared IRQ lines.\n");
	}

	if (req->Handler) {
		ret = request_irq(irq, req->Handler, type,
				  p_dev->devname, p_dev->priv);
		if (ret) {
			dev_printk(KERN_INFO, &s->dev,
				"request_irq() failed\n");
			goto out;
		}
	}

	c->irq.Attributes = req->Attributes;
	req->AssignedIRQ = irq;

	p_dev->_irq = 1;

	ret = 0;
out:
	mutex_unlock(&s->ops_mutex);
	return ret;
} /* pcmcia_request_irq */
EXPORT_SYMBOL(pcmcia_request_irq);


#ifdef CONFIG_PCMCIA_PROBE

/* mask of IRQs already reserved by other cards, we should avoid using them */
static u8 pcmcia_used_irq[NR_IRQS];

static irqreturn_t test_action(int cpl, void *dev_id)
{
	return IRQ_NONE;
}

/**
 * pcmcia_setup_isa_irq() - determine whether an ISA IRQ can be used
 * @p_dev - the associated PCMCIA device
 *
 * locking note: must be called with ops_mutex locked.
 */
static int pcmcia_setup_isa_irq(struct pcmcia_device *p_dev, int type)
{
	struct pcmcia_socket *s = p_dev->socket;
	unsigned int try, irq;
	u32 mask = s->irq_mask;
	int ret = -ENODEV;

	for (try = 0; try < 64; try++) {
		irq = try % 32;

		/* marked as available by driver, not blocked by userspace? */
		if (!((mask >> irq) & 1))
			continue;

		/* avoid an IRQ which is already used by another PCMCIA card */
		if ((try < 32) && pcmcia_used_irq[irq])
			continue;

		/* register the correct driver, if possible, to check whether
		 * registering a dummy handle works, i.e. if the IRQ isn't
		 * marked as used by the kernel resource management core */
		ret = request_irq(irq, test_action, type, p_dev->devname,
				  p_dev);
		if (!ret) {
			free_irq(irq, p_dev);
			p_dev->irq_v = s->pcmcia_irq = irq;
			pcmcia_used_irq[irq]++;
			break;
		}
	}

	return ret;
}

void pcmcia_cleanup_irq(struct pcmcia_socket *s)
{
	pcmcia_used_irq[s->pcmcia_irq]--;
	s->pcmcia_irq = 0;
}

#else /* CONFIG_PCMCIA_PROBE */

static int pcmcia_setup_isa_irq(struct pcmcia_device *p_dev, int type)
{
	return -EINVAL;
}

void pcmcia_cleanup_irq(struct pcmcia_socket *s)
{
	s->pcmcia_irq = 0;
	return;
}

#endif  /* CONFIG_PCMCIA_PROBE */


/**
 * pcmcia_setup_irq() - determine IRQ to be used for device
 * @p_dev - the associated PCMCIA device
 *
 * locking note: must be called with ops_mutex locked.
 */
int pcmcia_setup_irq(struct pcmcia_device *p_dev)
{
	struct pcmcia_socket *s = p_dev->socket;

	if (p_dev->irq_v)
		return 0;

	/* already assigned? */
	if (s->pcmcia_irq) {
		p_dev->irq_v = s->pcmcia_irq;
		return 0;
	}

	/* prefer an exclusive ISA irq */
	if (!pcmcia_setup_isa_irq(p_dev, 0))
		return 0;

	/* but accept a shared ISA irq */
	if (!pcmcia_setup_isa_irq(p_dev, IRQF_SHARED))
		return 0;

	/* but use the PCI irq otherwise */
	if (s->pci_irq) {
		p_dev->irq_v = s->pcmcia_irq = s->pci_irq;
		return 0;
	}

	return -EINVAL;
}


/** pcmcia_request_window
 *
 * Request_window() establishes a mapping between card memory space
 * and system memory space.
 */
int pcmcia_request_window(struct pcmcia_device *p_dev, win_req_t *req, window_handle_t *wh)
{
	struct pcmcia_socket *s = p_dev->socket;
	pccard_mem_map *win;
	u_long align;
	int w;

	if (!(s->state & SOCKET_PRESENT)) {
		dev_dbg(&s->dev, "No card present\n");
		return -ENODEV;
	}
	if (req->Attributes & (WIN_PAGED | WIN_SHARED)) {
		dev_dbg(&s->dev, "bad attribute setting for iomem region\n");
		return -EINVAL;
	}

	/* Window size defaults to smallest available */
	if (req->Size == 0)
		req->Size = s->map_size;
	align = (((s->features & SS_CAP_MEM_ALIGN) ||
		  (req->Attributes & WIN_STRICT_ALIGN)) ?
		 req->Size : s->map_size);
	if (req->Size & (s->map_size-1)) {
		dev_dbg(&s->dev, "invalid map size\n");
		return -EINVAL;
	}
	if ((req->Base && (s->features & SS_CAP_STATIC_MAP)) ||
	    (req->Base & (align-1))) {
		dev_dbg(&s->dev, "invalid base address\n");
		return -EINVAL;
	}
	if (req->Base)
		align = 0;

	/* Allocate system memory window */
	for (w = 0; w < MAX_WIN; w++)
		if (!(s->state & SOCKET_WIN_REQ(w)))
			break;
	if (w == MAX_WIN) {
		dev_dbg(&s->dev, "all windows are used already\n");
		return -EINVAL;
	}

	mutex_lock(&s->ops_mutex);
	win = &s->win[w];

	if (!(s->features & SS_CAP_STATIC_MAP)) {
		win->res = pcmcia_find_mem_region(req->Base, req->Size, align,
						      (req->Attributes & WIN_MAP_BELOW_1MB), s);
		if (!win->res) {
			dev_dbg(&s->dev, "allocating mem region failed\n");
			mutex_unlock(&s->ops_mutex);
			return -EINVAL;
		}
	}
	p_dev->_win |= CLIENT_WIN_REQ(w);

	/* Configure the socket controller */
	win->map = w+1;
	win->flags = 0;
	win->speed = req->AccessSpeed;
	if (req->Attributes & WIN_MEMORY_TYPE)
		win->flags |= MAP_ATTRIB;
	if (req->Attributes & WIN_ENABLE)
		win->flags |= MAP_ACTIVE;
	if (req->Attributes & WIN_DATA_WIDTH_16)
		win->flags |= MAP_16BIT;
	if (req->Attributes & WIN_USE_WAIT)
		win->flags |= MAP_USE_WAIT;
	win->card_start = 0;

	if (s->ops->set_mem_map(s, win) != 0) {
		dev_dbg(&s->dev, "failed to set memory mapping\n");
		mutex_unlock(&s->ops_mutex);
		return -EIO;
	}
	s->state |= SOCKET_WIN_REQ(w);

	/* Return window handle */
	if (s->features & SS_CAP_STATIC_MAP)
		req->Base = win->static_start;
	else
		req->Base = win->res->start;

	mutex_unlock(&s->ops_mutex);
	*wh = w + 1;

	return 0;
} /* pcmcia_request_window */
EXPORT_SYMBOL(pcmcia_request_window);

void pcmcia_disable_device(struct pcmcia_device *p_dev)
{
	pcmcia_release_configuration(p_dev);
	pcmcia_release_io(p_dev, &p_dev->io);
	pcmcia_release_irq(p_dev, &p_dev->irq);
	if (p_dev->win)
		pcmcia_release_window(p_dev, p_dev->win);
}
EXPORT_SYMBOL(pcmcia_disable_device);


struct pcmcia_cfg_mem {
	struct pcmcia_device *p_dev;
	void *priv_data;
	int (*conf_check) (struct pcmcia_device *p_dev,
			   cistpl_cftable_entry_t *cfg,
			   cistpl_cftable_entry_t *dflt,
			   unsigned int vcc,
			   void *priv_data);
	cisparse_t parse;
	cistpl_cftable_entry_t dflt;
};

/**
 * pcmcia_do_loop_config() - internal helper for pcmcia_loop_config()
 *
 * pcmcia_do_loop_config() is the internal callback for the call from
 * pcmcia_loop_config() to pccard_loop_tuple(). Data is transferred
 * by a struct pcmcia_cfg_mem.
 */
static int pcmcia_do_loop_config(tuple_t *tuple, cisparse_t *parse, void *priv)
{
	cistpl_cftable_entry_t *cfg = &parse->cftable_entry;
	struct pcmcia_cfg_mem *cfg_mem = priv;

	/* default values */
	cfg_mem->p_dev->conf.ConfigIndex = cfg->index;
	if (cfg->flags & CISTPL_CFTABLE_DEFAULT)
		cfg_mem->dflt = *cfg;

	return cfg_mem->conf_check(cfg_mem->p_dev, cfg, &cfg_mem->dflt,
				   cfg_mem->p_dev->socket->socket.Vcc,
				   cfg_mem->priv_data);
}

/**
 * pcmcia_loop_config() - loop over configuration options
 * @p_dev:	the struct pcmcia_device which we need to loop for.
 * @conf_check:	function to call for each configuration option.
 *		It gets passed the struct pcmcia_device, the CIS data
 *		describing the configuration option, and private data
 *		being passed to pcmcia_loop_config()
 * @priv_data:	private data to be passed to the conf_check function.
 *
 * pcmcia_loop_config() loops over all configuration options, and calls
 * the driver-specific conf_check() for each one, checking whether
 * it is a valid one. Returns 0 on success or errorcode otherwise.
 */
int pcmcia_loop_config(struct pcmcia_device *p_dev,
		       int	(*conf_check)	(struct pcmcia_device *p_dev,
						 cistpl_cftable_entry_t *cfg,
						 cistpl_cftable_entry_t *dflt,
						 unsigned int vcc,
						 void *priv_data),
		       void *priv_data)
{
	struct pcmcia_cfg_mem *cfg_mem;
	int ret;

	cfg_mem = kzalloc(sizeof(struct pcmcia_cfg_mem), GFP_KERNEL);
	if (cfg_mem == NULL)
		return -ENOMEM;

	cfg_mem->p_dev = p_dev;
	cfg_mem->conf_check = conf_check;
	cfg_mem->priv_data = priv_data;

	ret = pccard_loop_tuple(p_dev->socket, p_dev->func,
				CISTPL_CFTABLE_ENTRY, &cfg_mem->parse,
				cfg_mem, pcmcia_do_loop_config);

	kfree(cfg_mem);
	return ret;
}
EXPORT_SYMBOL(pcmcia_loop_config);


struct pcmcia_loop_mem {
	struct pcmcia_device *p_dev;
	void *priv_data;
	int (*loop_tuple) (struct pcmcia_device *p_dev,
			   tuple_t *tuple,
			   void *priv_data);
};

/**
 * pcmcia_do_loop_tuple() - internal helper for pcmcia_loop_config()
 *
 * pcmcia_do_loop_tuple() is the internal callback for the call from
 * pcmcia_loop_tuple() to pccard_loop_tuple(). Data is transferred
 * by a struct pcmcia_cfg_mem.
 */
static int pcmcia_do_loop_tuple(tuple_t *tuple, cisparse_t *parse, void *priv)
{
	struct pcmcia_loop_mem *loop = priv;

	return loop->loop_tuple(loop->p_dev, tuple, loop->priv_data);
};

/**
 * pcmcia_loop_tuple() - loop over tuples in the CIS
 * @p_dev:	the struct pcmcia_device which we need to loop for.
 * @code:	which CIS code shall we look for?
 * @priv_data:	private data to be passed to the loop_tuple function.
 * @loop_tuple:	function to call for each CIS entry of type @function. IT
 *		gets passed the raw tuple and @priv_data.
 *
 * pcmcia_loop_tuple() loops over all CIS entries of type @function, and
 * calls the @loop_tuple function for each entry. If the call to @loop_tuple
 * returns 0, the loop exits. Returns 0 on success or errorcode otherwise.
 */
int pcmcia_loop_tuple(struct pcmcia_device *p_dev, cisdata_t code,
		      int (*loop_tuple) (struct pcmcia_device *p_dev,
					 tuple_t *tuple,
					 void *priv_data),
		      void *priv_data)
{
	struct pcmcia_loop_mem loop = {
		.p_dev = p_dev,
		.loop_tuple = loop_tuple,
		.priv_data = priv_data};

	return pccard_loop_tuple(p_dev->socket, p_dev->func, code, NULL,
				 &loop, pcmcia_do_loop_tuple);
}
EXPORT_SYMBOL(pcmcia_loop_tuple);


struct pcmcia_loop_get {
	size_t len;
	cisdata_t **buf;
};

/**
 * pcmcia_do_get_tuple() - internal helper for pcmcia_get_tuple()
 *
 * pcmcia_do_get_tuple() is the internal callback for the call from
 * pcmcia_get_tuple() to pcmcia_loop_tuple(). As we're only interested in
 * the first tuple, return 0 unconditionally. Create a memory buffer large
 * enough to hold the content of the tuple, and fill it with the tuple data.
 * The caller is responsible to free the buffer.
 */
static int pcmcia_do_get_tuple(struct pcmcia_device *p_dev, tuple_t *tuple,
			       void *priv)
{
	struct pcmcia_loop_get *get = priv;

	*get->buf = kzalloc(tuple->TupleDataLen, GFP_KERNEL);
	if (*get->buf) {
		get->len = tuple->TupleDataLen;
		memcpy(*get->buf, tuple->TupleData, tuple->TupleDataLen);
	} else
		dev_dbg(&p_dev->dev, "do_get_tuple: out of memory\n");
	return 0;
}

/**
 * pcmcia_get_tuple() - get first tuple from CIS
 * @p_dev:	the struct pcmcia_device which we need to loop for.
 * @code:	which CIS code shall we look for?
 * @buf:        pointer to store the buffer to.
 *
 * pcmcia_get_tuple() gets the content of the first CIS entry of type @code.
 * It returns the buffer length (or zero). The caller is responsible to free
 * the buffer passed in @buf.
 */
size_t pcmcia_get_tuple(struct pcmcia_device *p_dev, cisdata_t code,
			unsigned char **buf)
{
	struct pcmcia_loop_get get = {
		.len = 0,
		.buf = buf,
	};

	*get.buf = NULL;
	pcmcia_loop_tuple(p_dev, code, pcmcia_do_get_tuple, &get);

	return get.len;
}
EXPORT_SYMBOL(pcmcia_get_tuple);


/**
 * pcmcia_do_get_mac() - internal helper for pcmcia_get_mac_from_cis()
 *
 * pcmcia_do_get_mac() is the internal callback for the call from
 * pcmcia_get_mac_from_cis() to pcmcia_loop_tuple(). We check whether the
 * tuple contains a proper LAN_NODE_ID of length 6, and copy the data
 * to struct net_device->dev_addr[i].
 */
static int pcmcia_do_get_mac(struct pcmcia_device *p_dev, tuple_t *tuple,
			     void *priv)
{
	struct net_device *dev = priv;
	int i;

	if (tuple->TupleData[0] != CISTPL_FUNCE_LAN_NODE_ID)
		return -EINVAL;
	if (tuple->TupleDataLen < ETH_ALEN + 2) {
		dev_warn(&p_dev->dev, "Invalid CIS tuple length for "
			"LAN_NODE_ID\n");
		return -EINVAL;
	}

	if (tuple->TupleData[1] != ETH_ALEN) {
		dev_warn(&p_dev->dev, "Invalid header for LAN_NODE_ID\n");
		return -EINVAL;
	}
	for (i = 0; i < 6; i++)
		dev->dev_addr[i] = tuple->TupleData[i+2];
	return 0;
}

/**
 * pcmcia_get_mac_from_cis() - read out MAC address from CISTPL_FUNCE
 * @p_dev:	the struct pcmcia_device for which we want the address.
 * @dev:	a properly prepared struct net_device to store the info to.
 *
 * pcmcia_get_mac_from_cis() reads out the hardware MAC address from
 * CISTPL_FUNCE and stores it into struct net_device *dev->dev_addr which
 * must be set up properly by the driver (see examples!).
 */
int pcmcia_get_mac_from_cis(struct pcmcia_device *p_dev, struct net_device *dev)
{
	return pcmcia_loop_tuple(p_dev, CISTPL_FUNCE, pcmcia_do_get_mac, dev);
}
EXPORT_SYMBOL(pcmcia_get_mac_from_cis);