text: /*********************************************************************
   *
   * msnd.c - Driver Base
   *
   * Turtle Beach MultiSound Sound Card Driver for Linux
   *
   * Copyright (C) 1998 Andrew Veliath
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
   *
   * $Id: msnd.c,v 1.1.1.4 2003/10/14 08:08:46 sparq Exp $
   *
   ********************************************************************/
  
  #include <linux/version.h>
  #if LINUX_VERSION_CODE < 0x020101
  #  define LINUX20
  #endif
  #include <linux/module.h>
  #include <linux/kernel.h>
  #include <linux/slab.h>
  #include <linux/vmalloc.h>
  #include <linux/types.h>
  #include <linux/delay.h>
  #include <linux/mm.h>
  #ifdef LINUX20
  #  include <linux/major.h>
  #  include <linux/fs.h>
  #  include <linux/sound.h>
  #  include <asm/segment.h>
  #  include "sound_config.h"
  #else
  #  include <linux/init.h>
  #  include <asm/io.h>
  #  include <asm/uaccess.h>
  #  include <linux/spinlock.h>
  #endif
  #include <asm/irq.h>
  #include "msnd.h"
  
  #define LOGNAME			"msnd"
  
  #define MSND_MAX_DEVS		4
  
  static multisound_dev_t		*devs[MSND_MAX_DEVS];
  static int			num_devs;
  
  int __init msnd_register(multisound_dev_t *dev)
  {
  	int i;
  
  	for (i = 0; i < MSND_MAX_DEVS; ++i)
  		if (devs[i] == NULL)
  			break;
  
  	if (i == MSND_MAX_DEVS)
  		return -ENOMEM;
  
  	devs[i] = dev;
  	++num_devs;
  
  	MOD_INC_USE_COUNT;
  
  	return 0;
  }
  
  void msnd_unregister(multisound_dev_t *dev)
  {
  	int i;
  
  	for (i = 0; i < MSND_MAX_DEVS; ++i)
  		if (devs[i] == dev)
  			break;
  
  	if (i == MSND_MAX_DEVS) {
  		printk(KERN_WARNING LOGNAME ": Unregistering unknown device\n");
  		return;
  	}
  
  	devs[i] = NULL;
  	--num_devs;
  
  	MOD_DEC_USE_COUNT;
  }
  
  int msnd_get_num_devs(void)
  {
  	return num_devs;
  }
  
  multisound_dev_t *msnd_get_dev(int j)
  {
  	int i;
  
  	for (i = 0; i < MSND_MAX_DEVS && j; ++i)
  		if (devs[i] != NULL)
  			--j;
  
  	if (i == MSND_MAX_DEVS || j != 0)
  		return NULL;
  
  	return devs[i];
  }
  
  void msnd_init_queue(unsigned long base, int start, int size)
  {
  	isa_writew(PCTODSP_BASED(start), base + JQS_wStart);
  	isa_writew(PCTODSP_OFFSET(size) - 1, base + JQS_wSize);
  	isa_writew(0, base + JQS_wHead);
  	isa_writew(0, base + JQS_wTail);
  }
  
  void msnd_fifo_init(msnd_fifo *f)
  {
  	f->data = NULL;
  }
  
  void msnd_fifo_free(msnd_fifo *f)
  {
  	if (f->data) {
  		vfree(f->data);
  		f->data = NULL;
  	}
  }
  
  int msnd_fifo_alloc(msnd_fifo *f, size_t n)
  {
  	msnd_fifo_free(f);
  	f->data = (char *)vmalloc(n);
  	f->n = n;
  	f->tail = 0;
  	f->head = 0;
  	f->len = 0;
  
  	if (!f->data)
  		return -ENOMEM;
  
  	return 0;
  }
  
  void msnd_fifo_make_empty(msnd_fifo *f)
  {
  	f->len = f->tail = f->head = 0;
  }
  
  int msnd_fifo_write(msnd_fifo *f, const char *buf, size_t len, int user)
  {
  	int count = 0;
  
  	if (f->len == f->n)
  		return 0;
  
  	while ((count < len) && (f->len != f->n)) {
  
  		int nwritten;
  
  		if (f->head <= f->tail) {
  			nwritten = len - count;
  			if (nwritten > f->n - f->tail)
  				nwritten = f->n - f->tail;
  		}
  		else {
  			nwritten = f->head - f->tail;
  			if (nwritten > len - count)
  				nwritten = len - count;
  		}
  
  		if (user) {
  			if (copy_from_user(f->data + f->tail, buf, nwritten))
  				return -EFAULT;
  		} else
  			isa_memcpy_fromio(f->data + f->tail, (unsigned long) buf, nwritten);
  
  		count += nwritten;
  		buf += nwritten;
  		f->len += nwritten;
  		f->tail += nwritten;
  		f->tail %= f->n;
  	}
  
  	return count;
  }
  
  int msnd_fifo_read(msnd_fifo *f, char *buf, size_t len, int user)
  {
  	int count = 0;
  
  	if (f->len == 0)
  		return f->len;
  
  	while ((count < len) && (f->len > 0)) {
  
  		int nread;
  
  		if (f->tail <= f->head) {
  			nread = len - count;
  			if (nread > f->n - f->head)
  				nread = f->n - f->head;
  		}
  		else {
  			nread = f->tail - f->head;
  			if (nread > len - count)
  				nread = len - count;
  		}
  
  		if (user) {
  			if (copy_to_user(buf, f->data + f->head, nread))
  				return -EFAULT;
  		} else
  			isa_memcpy_toio((unsigned long) buf, f->data + f->head, nread);
  
  		count += nread;
  		buf += nread;
  		f->len -= nread;
  		f->head += nread;
  		f->head %= f->n;
  	}
  
  	return count;
  }
  
  int msnd_wait_TXDE(multisound_dev_t *dev)
  {
  	register unsigned int io = dev->io;
  	register int timeout = 1000;
      
  	while(timeout-- > 0)
  		if (inb(io + HP_ISR) & HPISR_TXDE)
  			return 0;
  
  	return -EIO;
  }
  
  int msnd_wait_HC0(multisound_dev_t *dev)
  {
  	register unsigned int io = dev->io;
  	register int timeout = 1000;
  
  	while(timeout-- > 0)
  		if (!(inb(io + HP_CVR) & HPCVR_HC))
  			return 0;
  
  	return -EIO;
  }
  
  int msnd_send_dsp_cmd(multisound_dev_t *dev, BYTE cmd)
  {
  	unsigned long flags;
  
  	spin_lock_irqsave(&dev->lock, flags);
  	if (msnd_wait_HC0(dev) == 0) {
  		outb(cmd, dev->io + HP_CVR);
  		spin_unlock_irqrestore(&dev->lock, flags);
  		return 0;
  	}
  	spin_unlock_irqrestore(&dev->lock, flags);
  
  	printk(KERN_DEBUG LOGNAME ": Send DSP command timeout\n");
  
  	return -EIO;
  }
  
  int msnd_send_word(multisound_dev_t *dev, unsigned char high,
  		   unsigned char mid, unsigned char low)
  {
  	register unsigned int io = dev->io;
  
  	if (msnd_wait_TXDE(dev) == 0) {
  		outb(high, io + HP_TXH);
  		outb(mid, io + HP_TXM);
  		outb(low, io + HP_TXL);
  		return 0;
  	}
  
  	printk(KERN_DEBUG LOGNAME ": Send host word timeout\n");
  
  	return -EIO;
  }
  
  int msnd_upload_host(multisound_dev_t *dev, char *bin, int len)
  {
  	int i;
  
  	if (len % 3 != 0) {
  		printk(KERN_WARNING LOGNAME ": Upload host data not multiple of 3!\n");		
  		return -EINVAL;
  	}
  
  	for (i = 0; i < len; i += 3)
  		if (msnd_send_word(dev, bin[i], bin[i + 1], bin[i + 2]) != 0)
  			return -EIO;
  
  	inb(dev->io + HP_RXL);
  	inb(dev->io + HP_CVR);
  
  	return 0;
  }
  
  int msnd_enable_irq(multisound_dev_t *dev)
  {
  	unsigned long flags;
  
  	if (dev->irq_ref++)
  		return 0;
  
  	printk(KERN_DEBUG LOGNAME ": Enabling IRQ\n");
  
  	spin_lock_irqsave(&dev->lock, flags);
  	if (msnd_wait_TXDE(dev) == 0) {
  		outb(inb(dev->io + HP_ICR) | HPICR_TREQ, dev->io + HP_ICR);
  		if (dev->type == msndClassic)
  			outb(dev->irqid, dev->io + HP_IRQM);
  		outb(inb(dev->io + HP_ICR) & ~HPICR_TREQ, dev->io + HP_ICR);
  		outb(inb(dev->io + HP_ICR) | HPICR_RREQ, dev->io + HP_ICR);
  		enable_irq(dev->irq);
  		msnd_init_queue(dev->DSPQ, dev->dspq_data_buff, dev->dspq_buff_size);
  		spin_unlock_irqrestore(&dev->lock, flags);
  		return 0;
  	}
  	spin_unlock_irqrestore(&dev->lock, flags);
  
  	printk(KERN_DEBUG LOGNAME ": Enable IRQ failed\n");
  
  	return -EIO;
  }
  
  int msnd_disable_irq(multisound_dev_t *dev)
  {
  	unsigned long flags;
  
  	if (--dev->irq_ref > 0)
  		return 0;
  
  	if (dev->irq_ref < 0)
  		printk(KERN_DEBUG LOGNAME ": IRQ ref count is %d\n", dev->irq_ref);
  
  	printk(KERN_DEBUG LOGNAME ": Disabling IRQ\n");
  
  	spin_lock_irqsave(&dev->lock, flags);
  	if (msnd_wait_TXDE(dev) == 0) {
  		outb(inb(dev->io + HP_ICR) & ~HPICR_RREQ, dev->io + HP_ICR);
  		if (dev->type == msndClassic)
  			outb(HPIRQ_NONE, dev->io + HP_IRQM);
  		disable_irq(dev->irq);
  		spin_unlock_irqrestore(&dev->lock, flags);
  		return 0;
  	}
  	spin_unlock_irqrestore(&dev->lock, flags);
  
  	printk(KERN_DEBUG LOGNAME ": Disable IRQ failed\n");
  
  	return -EIO;
  }
  
  #ifndef LINUX20
  EXPORT_SYMBOL(msnd_register);
  EXPORT_SYMBOL(msnd_unregister);
  EXPORT_SYMBOL(msnd_get_num_devs);
  EXPORT_SYMBOL(msnd_get_dev);
  
  EXPORT_SYMBOL(msnd_init_queue);
  
  EXPORT_SYMBOL(msnd_fifo_init);
  EXPORT_SYMBOL(msnd_fifo_free);
  EXPORT_SYMBOL(msnd_fifo_alloc);
  EXPORT_SYMBOL(msnd_fifo_make_empty);
  EXPORT_SYMBOL(msnd_fifo_write);
  EXPORT_SYMBOL(msnd_fifo_read);
  
  EXPORT_SYMBOL(msnd_wait_TXDE);
  EXPORT_SYMBOL(msnd_wait_HC0);
  EXPORT_SYMBOL(msnd_send_dsp_cmd);
  EXPORT_SYMBOL(msnd_send_word);
  EXPORT_SYMBOL(msnd_upload_host);
  
  EXPORT_SYMBOL(msnd_enable_irq);
  EXPORT_SYMBOL(msnd_disable_irq);
  #endif
  
  #ifdef MODULE
  MODULE_AUTHOR				("Andrew Veliath <andrewtv@usa.net>");
  MODULE_DESCRIPTION			("Turtle Beach MultiSound Driver Base");
  MODULE_LICENSE("GPL");
  
  
  int init_module(void)
  {
  	return 0;
  }
  
  void cleanup_module(void)
  {
  }
  #endif
  