// SPDX-License-Identifier: GPL-2.0-only

  /*
   * 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) 2004-2010   Dominik Brodowski

   */

  #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/ss.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);

  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;
  }

  /**
   * release_io_space() - release IO ports allocated with alloc_io_space()
   * @s: pcmcia socket
   * @res: resource to release
   *
   */

  static void release_io_space(struct pcmcia_socket *s, struct resource *res)
  {
  	resource_size_t num = resource_size(res);
  	int i;
  
  	dev_dbg(&s->dev, "release_io_space for %pR
  ", res);
  
  	for (i = 0; i < MAX_IO_WIN; i++) {
  		if (!s->io[i].res)
  			continue;
  		if ((s->io[i].res->start <= res->start) &&
  		    (s->io[i].res->end >= res->end)) {
  			s->io[i].InUse -= num;
  			if (res->parent)
  				release_resource(res);
  			res->start = res->end = 0;
  			res->flags = IORESOURCE_IO;
  			/* 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;
  			}
  		}
  	}

  }

  /**
   * alloc_io_space() - allocate IO ports for use by a PCMCIA device
   * @s: pcmcia socket
   * @res: resource to allocate (begin: begin, end: size)
   * @lines: number of IO lines decoded by the PCMCIA card

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

  static int alloc_io_space(struct pcmcia_socket *s, struct resource *res,
  			unsigned int lines)

  {

  	unsigned int align;

  	unsigned int base = res->start;
  	unsigned int num = res->end;
  	int ret;
  
  	res->flags |= IORESOURCE_IO;

  	dev_dbg(&s->dev, "alloc_io_space request for %pR, %d lines
  ",
  		res, lines);

  
  	align = base ? (lines ? 1<<lines : 0) : 1;

  	if (align && (align < num)) {

  		if (base) {
  			dev_dbg(&s->dev, "odd IO request
  ");

  			align = 0;
  		} else

  			while (align && (align < num))
  				align <<= 1;

  	}

  	if (base & ~(align-1)) {
  		dev_dbg(&s->dev, "odd IO request
  ");

  		align = 0;
  	}

  	ret = s->resource_ops->find_io(s, res->flags, &base, num, align,
  				&res->parent);

  	if (ret) {

  		dev_dbg(&s->dev, "alloc_io_space request failed (%d)
  ", ret);

  		return -EINVAL;
  	}
  
  	res->start = base;
  	res->end = res->start + num - 1;

  	if (res->parent) {
  		ret = request_resource(res->parent, res);
  		if (ret) {
  			dev_warn(&s->dev,
  				"request_resource %pR failed: %d
  ", res, ret);
  			res->parent = NULL;
  			release_io_space(s, res);

  		}
  	}

  	dev_dbg(&s->dev, "alloc_io_space request result %d: %pR
  ", ret, res);
  	return ret;

  }

  /**
   * pcmcia_access_config() - read or write card configuration registers

   *

   * pcmcia_access_config() reads and writes configuration registers in
   * attribute memory.  Memory window 0 is reserved for this and the tuple
   * reading services. Drivers must use pcmcia_read_config_byte() or
   * pcmcia_write_config_byte().

   */

  static int pcmcia_access_config(struct pcmcia_device *p_dev,
  				off_t where, u8 *val,
  				int (*accessf) (struct pcmcia_socket *s,
  						int attr, unsigned int addr,
  						unsigned int len, void *ptr))

  {

  	struct pcmcia_socket *s;

  	config_t *c;
  	int addr;

  	int ret = 0;

  	s = p_dev->socket;

  
  	mutex_lock(&s->ops_mutex);

  	c = p_dev->function_config;

  	if (!(c->state & CONFIG_LOCKED)) {

  		dev_dbg(&p_dev->dev, "Configuration isn't locked
  ");

  		mutex_unlock(&s->ops_mutex);

  		return -EACCES;

  	}

  	addr = (p_dev->config_base + where) >> 1;

  
  	ret = accessf(s, 1, addr, 1, val);

  	mutex_unlock(&s->ops_mutex);

  	return ret;

  }

  
  
  /**
   * pcmcia_read_config_byte() - read a byte from a card configuration register
   *
   * pcmcia_read_config_byte() reads a byte from a configuration register in
   * attribute memory.
   */
  int pcmcia_read_config_byte(struct pcmcia_device *p_dev, off_t where, u8 *val)
  {
  	return pcmcia_access_config(p_dev, where, val, pcmcia_read_cis_mem);
  }
  EXPORT_SYMBOL(pcmcia_read_config_byte);
  
  
  /**
   * pcmcia_write_config_byte() - write a byte to a card configuration register
   *
   * pcmcia_write_config_byte() writes a byte to a configuration register in
   * attribute memory.
   */
  int pcmcia_write_config_byte(struct pcmcia_device *p_dev, off_t where, u8 val)
  {
  	return pcmcia_access_config(p_dev, where, &val, pcmcia_write_cis_mem);
  }
  EXPORT_SYMBOL(pcmcia_write_config_byte);

  /**
   * pcmcia_map_mem_page() - modify iomem window to point to a different offset
   * @p_dev: pcmcia device
   * @res: iomem resource already enabled by pcmcia_request_window()
   * @offset: card_offset to map
   *
   * pcmcia_map_mem_page() modifies what can be read and written by accessing
   * an iomem range previously enabled by pcmcia_request_window(), by setting
   * the card_offset value to @offset.
   */

  int pcmcia_map_mem_page(struct pcmcia_device *p_dev, struct resource *res,

  			unsigned int offset)

  {

  	struct pcmcia_socket *s = p_dev->socket;

  	unsigned int w;

  	int ret;

  	w = ((res->flags & IORESOURCE_BITS & WIN_FLAGS_REQ) >> 2) - 1;
  	if (w >= MAX_WIN)

  		return -EINVAL;

  	mutex_lock(&s->ops_mutex);

  	s->win[w].card_start = offset;
  	ret = s->ops->set_mem_map(s, &s->win[w]);

  	if (ret)

  		dev_warn(&p_dev->dev, "failed to set_mem_map
  ");

  	mutex_unlock(&s->ops_mutex);
  	return ret;

  }

  EXPORT_SYMBOL(pcmcia_map_mem_page);

  /**
   * pcmcia_fixup_iowidth() - reduce io width to 8bit

   * @p_dev: pcmcia device

   *

   * pcmcia_fixup_iowidth() allows a PCMCIA device driver to reduce the

   * IO width to 8bit after having called pcmcia_enable_device()

   * previously.

   */

  int pcmcia_fixup_iowidth(struct pcmcia_device *p_dev)

  {

  	struct pcmcia_socket *s = p_dev->socket;
  	pccard_io_map io_off = { 0, 0, 0, 0, 1 };
  	pccard_io_map io_on;
  	int i, ret = 0;

  
  	mutex_lock(&s->ops_mutex);

  	dev_dbg(&p_dev->dev, "fixup iowidth to 8bit
  ");
  
  	if (!(s->state & SOCKET_PRESENT) ||
  		!(p_dev->function_config->state & CONFIG_LOCKED)) {
  		dev_dbg(&p_dev->dev, "No card? Config not locked?
  ");

  		ret = -EACCES;
  		goto unlock;

  	}

  	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);

  		msleep(40);

  		s->ops->set_io_map(s, &io_on);

  	}

  unlock:
  	mutex_unlock(&s->ops_mutex);

  	return ret;
  }
  EXPORT_SYMBOL(pcmcia_fixup_iowidth);
  
  
  /**
   * pcmcia_fixup_vpp() - set Vpp to a new voltage level

   * @p_dev: pcmcia device
   * @new_vpp: new Vpp voltage

   *
   * pcmcia_fixup_vpp() allows a PCMCIA device driver to set Vpp to

   * a new voltage level between calls to pcmcia_enable_device()

   * and pcmcia_disable_device().
   */
  int pcmcia_fixup_vpp(struct pcmcia_device *p_dev, unsigned char new_vpp)
  {
  	struct pcmcia_socket *s = p_dev->socket;
  	int ret = 0;
  
  	mutex_lock(&s->ops_mutex);
  
  	dev_dbg(&p_dev->dev, "fixup Vpp to %d
  ", new_vpp);
  
  	if (!(s->state & SOCKET_PRESENT) ||
  		!(p_dev->function_config->state & CONFIG_LOCKED)) {
  		dev_dbg(&p_dev->dev, "No card? Config not locked?
  ");
  		ret = -EACCES;

  		goto unlock;

  	}

  	s->socket.Vpp = new_vpp;
  	if (s->ops->set_socket(s, &s->socket)) {
  		dev_warn(&p_dev->dev, "Unable to set VPP
  ");
  		ret = -EIO;
  		goto unlock;

  	}

  	p_dev->vpp = new_vpp;

  unlock:

  	mutex_unlock(&s->ops_mutex);

  	return ret;

  }
  EXPORT_SYMBOL(pcmcia_fixup_vpp);

  /**
   * pcmcia_release_configuration() - physically disable a PCMCIA device
   * @p_dev: pcmcia device
   *
   * pcmcia_release_configuration() is the 1:1 counterpart to
   * pcmcia_enable_device(): If a PCMCIA device is no longer used by any
   * driver, the Vpp voltage is set to 0, IRQs will no longer be generated,
   * and I/O ranges will be disabled. As pcmcia_release_io() and
   * pcmcia_release_window() still need to be called, device drivers are
   * expected to call pcmcia_disable_device() instead.
   */

  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_io() - release I/O allocated by a PCMCIA device
   * @p_dev: pcmcia device

   *

   * pcmcia_release_io() releases the I/O ranges allocated by a PCMCIA
   * device.  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)

  {

  	struct pcmcia_socket *s = p_dev->socket;

  	int ret = -EINVAL;
  	config_t *c;
  
  	mutex_lock(&s->ops_mutex);

  	if (!p_dev->_io)

  		goto out;

  	c = p_dev->function_config;

  	release_io_space(s, &c->io[0]);

  	if (c->io[1].end)
  		release_io_space(s, &c->io[1]);

  	p_dev->_io = 0;
  	c->state &= ~CONFIG_IO_REQ;

  out:
  	mutex_unlock(&s->ops_mutex);
  
  	return ret;

  } /* pcmcia_release_io */

  /**
   * pcmcia_release_window() - release reserved iomem for PCMCIA devices

   * @p_dev: pcmcia device
   * @res: iomem resource to release

   *

   * pcmcia_release_window() releases &struct resource *res which was

   * previously reserved by calling pcmcia_request_window().
   */

  int pcmcia_release_window(struct pcmcia_device *p_dev, struct resource *res)

  {

  	struct pcmcia_socket *s = p_dev->socket;

  	pccard_mem_map *win;

  	unsigned int w;

  	dev_dbg(&p_dev->dev, "releasing window %pR
  ", res);
  
  	w = ((res->flags & IORESOURCE_BITS & WIN_FLAGS_REQ) >> 2) - 1;
  	if (w >= MAX_WIN)

  		return -EINVAL;

  	mutex_lock(&s->ops_mutex);

  	win = &s->win[w];

  	if (!(p_dev->_win & CLIENT_WIN_REQ(w))) {

  		dev_dbg(&p_dev->dev, "not releasing unknown window
  ");

  		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(w);

  
  	/* Release system memory */

  	if (win->res) {

  		release_resource(res);

  		release_resource(win->res);
  		kfree(win->res);
  		win->res = NULL;

  	}

  	res->start = res->end = 0;
  	res->flags = IORESOURCE_MEM;

  	p_dev->_win &= ~CLIENT_WIN_REQ(w);

  	mutex_unlock(&s->ops_mutex);

  	return 0;

  } /* pcmcia_release_window */
  EXPORT_SYMBOL(pcmcia_release_window);

  /**
   * pcmcia_enable_device() - set up and activate a PCMCIA device

   * @p_dev: the associated PCMCIA device

   *

   * pcmcia_enable_device() physically enables a PCMCIA device. It parses
   * the flags passed to in @flags and stored in @p_dev->flags and sets up
   * the Vpp voltage, enables the speaker line, I/O ports and store proper
   * values to configuration registers.

   */
  int pcmcia_enable_device(struct pcmcia_device *p_dev)

  {
  	int i;

  	unsigned int base;

  	struct pcmcia_socket *s = p_dev->socket;

  	config_t *c;
  	pccard_io_map iomap;

  	unsigned char status = 0;
  	unsigned char ext_status = 0;

  	unsigned char option = 0;

  	unsigned int flags = p_dev->config_flags;

  	if (!(s->state & SOCKET_PRESENT))

  		return -ENODEV;

  	mutex_lock(&s->ops_mutex);

  	c = p_dev->function_config;

  	if (c->state & CONFIG_LOCKED) {

  		mutex_unlock(&s->ops_mutex);

  		dev_dbg(&p_dev->dev, "Configuration is locked
  ");

  		return -EACCES;

  	}

  
  	/* Do power control.  We don't allow changes in Vcc. */

  	s->socket.Vpp = p_dev->vpp;

  	if (s->ops->set_socket(s, &s->socket)) {

  		mutex_unlock(&s->ops_mutex);

  		dev_warn(&p_dev->dev, "Unable to set socket state
  ");

  		return -EINVAL;
  	}

  	/* Pick memory or I/O card, DMA mode, interrupt */

  	if (p_dev->_io || flags & CONF_ENABLE_IRQ)
  		flags |= CONF_ENABLE_IOCARD;
  	if (flags & CONF_ENABLE_IOCARD)

  		s->socket.flags |= SS_IOCARD;

  	if (flags & CONF_ENABLE_ZVCARD)
  		s->socket.flags |= SS_ZVCARD | SS_IOCARD;

  	if (flags & CONF_ENABLE_SPKR) {

  		s->socket.flags |= SS_SPKR_ENA;

  		status = CCSR_AUDIO_ENA;

  		if (!(p_dev->config_regs & PRESENT_STATUS))

  			dev_warn(&p_dev->dev, "speaker requested, but "
  					      "PRESENT_STATUS not set!
  ");
  	}

  	if (flags & CONF_ENABLE_IRQ)

  		s->socket.io_irq = s->pcmcia_irq;

  	else
  		s->socket.io_irq = 0;

  	if (flags & CONF_ENABLE_ESR) {

  		p_dev->config_regs |= PRESENT_EXT_STATUS;

  		ext_status = ESR_REQ_ATTN_ENA;
  	}

  	s->ops->set_socket(s, &s->socket);
  	s->lock_count++;

  	dev_dbg(&p_dev->dev,
  		"enable_device: V %d, flags %x, base %x, regs %x, idx %x
  ",
  		p_dev->vpp, flags, p_dev->config_base, p_dev->config_regs,
  		p_dev->config_index);

  	/* Set up CIS configuration registers */

  	base = p_dev->config_base;
  	if (p_dev->config_regs & PRESENT_COPY) {

  		u16 tmp = 0;
  		dev_dbg(&p_dev->dev, "clearing CISREG_SCR
  ");
  		pcmcia_write_cis_mem(s, 1, (base + CISREG_SCR)>>1, 1, &tmp);
  	}

  	if (p_dev->config_regs & PRESENT_PIN_REPLACE) {

  		u16 tmp = 0;
  		dev_dbg(&p_dev->dev, "clearing CISREG_PRR
  ");
  		pcmcia_write_cis_mem(s, 1, (base + CISREG_PRR)>>1, 1, &tmp);

  	}

  	if (p_dev->config_regs & PRESENT_OPTION) {

  		if (s->functions == 1) {

  			option = p_dev->config_index & COR_CONFIG_MASK;

  		} else {

  			option = p_dev->config_index & COR_MFC_CONFIG_MASK;
  			option |= COR_FUNC_ENA|COR_IREQ_ENA;
  			if (p_dev->config_regs & PRESENT_IOBASE_0)
  				option |= COR_ADDR_DECODE;

  		}

  		if ((flags & CONF_ENABLE_IRQ) &&
  			!(flags & CONF_ENABLE_PULSE_IRQ))

  			option |= COR_LEVEL_REQ;
  		pcmcia_write_cis_mem(s, 1, (base + CISREG_COR)>>1, 1, &option);

  		msleep(40);

  	}

  	if (p_dev->config_regs & PRESENT_STATUS)

  		pcmcia_write_cis_mem(s, 1, (base + CISREG_CCSR)>>1, 1, &status);

  	if (p_dev->config_regs & PRESENT_EXT_STATUS)

  		pcmcia_write_cis_mem(s, 1, (base + CISREG_ESR)>>1, 1,
  					&ext_status);

  	if (p_dev->config_regs & PRESENT_IOBASE_0) {

  		u8 b = c->io[0].start & 0xff;

  		pcmcia_write_cis_mem(s, 1, (base + CISREG_IOBASE_0)>>1, 1, &b);

  		b = (c->io[0].start >> 8) & 0xff;

  		pcmcia_write_cis_mem(s, 1, (base + CISREG_IOBASE_1)>>1, 1, &b);
  	}

  	if (p_dev->config_regs & PRESENT_IOSIZE) {

  		u8 b = resource_size(&c->io[0]) + resource_size(&c->io[1]) - 1;

  		pcmcia_write_cis_mem(s, 1, (base + CISREG_IOSIZE)>>1, 1, &b);
  	}
  
  	/* Configure I/O windows */
  	if (c->state & CONFIG_IO_REQ) {
  		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++;
  			}
  	}
  
  	c->state |= CONFIG_LOCKED;

  	p_dev->_locked = 1;

  	mutex_unlock(&s->ops_mutex);

  	return 0;

  } /* pcmcia_enable_device */
  EXPORT_SYMBOL(pcmcia_enable_device);

  /**
   * pcmcia_request_io() - attempt to reserve port ranges for PCMCIA devices

   * @p_dev: the associated PCMCIA device

   *

   * pcmcia_request_io() attempts to reserve the IO port ranges specified in

   * &struct pcmcia_device @p_dev->resource[0] and @p_dev->resource[1]. The

   * "start" value is the requested start of the IO port resource; "end"

   * reflects the number of ports requested. The number of IO lines requested
   * is specified in &struct pcmcia_device @p_dev->io_lines.

   */

  int pcmcia_request_io(struct pcmcia_device *p_dev)

  {

  	struct pcmcia_socket *s = p_dev->socket;

  	config_t *c = p_dev->function_config;

  	int ret = -EINVAL;
  
  	mutex_lock(&s->ops_mutex);

  	dev_dbg(&p_dev->dev, "pcmcia_request_io: %pR , %pR",
  		&c->io[0], &c->io[1]);

  	if (!(s->state & SOCKET_PRESENT)) {

  		dev_dbg(&p_dev->dev, "pcmcia_request_io: No card present
  ");

  		goto out;

  	}

  	if (c->state & CONFIG_LOCKED) {

  		dev_dbg(&p_dev->dev, "Configuration is locked
  ");

  		goto out;

  	}

  	if (c->state & CONFIG_IO_REQ) {

  		dev_dbg(&p_dev->dev, "IO already configured
  ");

  		goto out;

  	}

  	ret = alloc_io_space(s, &c->io[0], p_dev->io_lines);

  	if (ret)

  		goto out;

  	if (c->io[1].end) {

  		ret = alloc_io_space(s, &c->io[1], p_dev->io_lines);

  		if (ret) {

  			struct resource tmp = c->io[0];
  			/* release the previously allocated resource */

  			release_io_space(s, &c->io[0]);

  			/* but preserve the settings, for they worked... */
  			c->io[0].end = resource_size(&tmp);
  			c->io[0].start = tmp.start;
  			c->io[0].flags = tmp.flags;

  			goto out;

  		}

  	} else
  		c->io[1].start = 0;

  	c->state |= CONFIG_IO_REQ;

  	p_dev->_io = 1;

  	dev_dbg(&p_dev->dev, "pcmcia_request_io succeeded: %pR , %pR",

  		&c->io[0], &c->io[1]);

  out:
  	mutex_unlock(&s->ops_mutex);
  
  	return ret;

  } /* pcmcia_request_io */
  EXPORT_SYMBOL(pcmcia_request_io);

  /**
   * pcmcia_request_irq() - attempt to request a IRQ for a PCMCIA device

   * @p_dev: the associated PCMCIA device
   * @handler: IRQ handler to register

   *

   * pcmcia_request_irq() is a wrapper around request_irq() which allows

   * the PCMCIA core to clean up the registration in pcmcia_disable_device().
   * Drivers are free to use request_irq() directly, but then they need to

   * call free_irq() themselfves, too. Also, only %IRQF_SHARED capable IRQ

   * handlers are allowed.

   */

  int __must_check pcmcia_request_irq(struct pcmcia_device *p_dev,
  				    irq_handler_t handler)

  {

  	int ret;

  	if (!p_dev->irq)
  		return -EINVAL;

  	ret = request_irq(p_dev->irq, handler, IRQF_SHARED,
  			p_dev->devname, p_dev->priv);
  	if (!ret)
  		p_dev->_irq = 1;

  	return ret;
  }
  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[32];

  
  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;

  		if (irq > NR_IRQS)
  			continue;

  		/* 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 = 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)

  		return 0;
  
  	/* already assigned? */

  	if (s->pcmcia_irq) {

  		p_dev->irq = 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 = s->pcmcia_irq = s->pci_irq;

  		return 0;
  	}
  
  	return -EINVAL;
  }

  /**
   * pcmcia_request_window() - attempt to reserve iomem for PCMCIA devices

   * @p_dev: the associated PCMCIA device
   * @res: &struct resource pointing to p_dev->resource[2..5]
   * @speed: access speed

   *

   * pcmcia_request_window() attepts to reserve an iomem ranges specified in

   * &struct resource @res pointing to one of the entries in
   * &struct pcmcia_device @p_dev->resource[2..5]. The "start" value is the

   * requested start of the IO mem resource; "end" reflects the size
   * requested.

   */

  int pcmcia_request_window(struct pcmcia_device *p_dev, struct resource *res,
  			unsigned int speed)

  {

  	struct pcmcia_socket *s = p_dev->socket;

  	pccard_mem_map *win;

  	u_long align;
  	int w;

  	dev_dbg(&p_dev->dev, "request_window %pR %d
  ", res, speed);

  	if (!(s->state & SOCKET_PRESENT)) {

  		dev_dbg(&p_dev->dev, "No card present
  ");

  		return -ENODEV;

  	}

  
  	/* Window size defaults to smallest available */

  	if (res->end == 0)
  		res->end = s->map_size;
  	align = (s->features & SS_CAP_MEM_ALIGN) ? res->end : s->map_size;
  	if (res->end & (s->map_size-1)) {

  		dev_dbg(&p_dev->dev, "invalid map size
  ");

  		return -EINVAL;
  	}

  	if ((res->start && (s->features & SS_CAP_STATIC_MAP)) ||
  	    (res->start & (align-1))) {

  		dev_dbg(&p_dev->dev, "invalid base address
  ");

  		return -EINVAL;
  	}

  	if (res->start)

  		align = 0;
  
  	/* Allocate system memory window */

  	mutex_lock(&s->ops_mutex);

  	for (w = 0; w < MAX_WIN; w++)

  		if (!(s->state & SOCKET_WIN_REQ(w)))
  			break;

  	if (w == MAX_WIN) {

  		dev_dbg(&p_dev->dev, "all windows are used already
  ");

  		mutex_unlock(&s->ops_mutex);

  		return -EINVAL;
  	}

  
  	win = &s->win[w];

  
  	if (!(s->features & SS_CAP_STATIC_MAP)) {

  		win->res = pcmcia_find_mem_region(res->start, res->end, align,

  						0, s);

  		if (!win->res) {

  			dev_dbg(&p_dev->dev, "allocating mem region failed
  ");

  			mutex_unlock(&s->ops_mutex);

  			return -EINVAL;
  		}

  	}

  	p_dev->_win |= CLIENT_WIN_REQ(w);

  
  	/* Configure the socket controller */

  	win->map = w+1;

  	win->flags = res->flags & WIN_FLAGS_MAP;
  	win->speed = speed;

  	win->card_start = 0;

  	if (s->ops->set_mem_map(s, win) != 0) {

  		dev_dbg(&p_dev->dev, "failed to set memory mapping
  ");

  		mutex_unlock(&s->ops_mutex);

  		return -EIO;
  	}

  	s->state |= SOCKET_WIN_REQ(w);
  
  	/* Return window handle */

  	if (s->features & SS_CAP_STATIC_MAP)

  		res->start = win->static_start;

  	else

  		res->start = win->res->start;

  	/* convert to new-style resources */

  	res->end += res->start - 1;
  	res->flags &= ~WIN_FLAGS_REQ;
  	res->flags |= (win->map << 2) | IORESOURCE_MEM;

  	res->parent = win->res;
  	if (win->res)
  		request_resource(&iomem_resource, res);

  	dev_dbg(&p_dev->dev, "request_window results in %pR
  ", res);

  	mutex_unlock(&s->ops_mutex);

  	return 0;

  } /* pcmcia_request_window */
  EXPORT_SYMBOL(pcmcia_request_window);

  
  /**
   * pcmcia_disable_device() - disable and clean up a PCMCIA device
   * @p_dev: the associated PCMCIA device
   *
   * pcmcia_disable_device() is the driver-callable counterpart to
   * pcmcia_enable_device(): If a PCMCIA device is no longer used,
   * drivers are expected to clean up and disable the device by calling
   * this function. Any I/O ranges (iomem and ioports) will be released,
   * the Vpp voltage will be set to 0, and IRQs will no longer be
   * generated -- at least if there is no other card function (of
   * multifunction devices) being used.
   */

  void pcmcia_disable_device(struct pcmcia_device *p_dev)
  {

  	int i;

  
  	dev_dbg(&p_dev->dev, "disabling device
  ");

  	for (i = 0; i < MAX_WIN; i++) {
  		struct resource *res = p_dev->resource[MAX_IO_WIN + i];
  		if (res->flags & WIN_FLAGS_REQ)
  			pcmcia_release_window(p_dev, res);
  	}

  	pcmcia_release_configuration(p_dev);

  	pcmcia_release_io(p_dev);

  	if (p_dev->_irq) {

  		free_irq(p_dev->irq, p_dev->priv);

  		p_dev->_irq = 0;
  	}

  }
  EXPORT_SYMBOL(pcmcia_disable_device);