/* Analog Devices 1889 audio driver
   *
   * This is a driver for the AD1889 PCI audio chipset found
   * on the HP PA-RISC [BCJ]-xxx0 workstations.
   *
   * Copyright (C) 2004-2005, Kyle McMartin <kyle@parisc-linux.org>
   * Copyright (C) 2005, Thibaut Varene <varenet@parisc-linux.org>
   *   Based on the OSS AD1889 driver by Randolph Chung <tausq@debian.org>
   *
   * 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.
   *
   * 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.
   *
   * TODO:
   *	Do we need to take care of CCS register?
   *	Maybe we could use finer grained locking (separate locks for pb/cap)?
   * Wishlist:
   *	Control Interface (mixer) support
   *	Better AC97 support (VSR...)?
   *	PM support
   *	MIDI support
   *	Game Port support
   *	SG DMA support (this will need *a lot* of work)
   */
  
  #include <linux/init.h>
  #include <linux/pci.h>
  #include <linux/dma-mapping.h>
  #include <linux/slab.h>
  #include <linux/interrupt.h>
  #include <linux/compiler.h>
  #include <linux/delay.h>
  #include <linux/module.h>
  #include <linux/io.h>
  
  #include <sound/core.h>
  #include <sound/pcm.h>
  #include <sound/initval.h>
  #include <sound/ac97_codec.h>
  
  #include "ad1889.h"
  #include "ac97/ac97_id.h"
  
  #define	AD1889_DRVVER	"Version: 1.7"
  
  MODULE_AUTHOR("Kyle McMartin <kyle@parisc-linux.org>, Thibaut Varene <t-bone@parisc-linux.org>");
  MODULE_DESCRIPTION("Analog Devices AD1889 ALSA sound driver");
  MODULE_LICENSE("GPL");
  MODULE_SUPPORTED_DEVICE("{{Analog Devices,AD1889}}");
  
  static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
  module_param_array(index, int, NULL, 0444);
  MODULE_PARM_DESC(index, "Index value for the AD1889 soundcard.");
  
  static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;
  module_param_array(id, charp, NULL, 0444);
  MODULE_PARM_DESC(id, "ID string for the AD1889 soundcard.");
  
  static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;
  module_param_array(enable, bool, NULL, 0444);
  MODULE_PARM_DESC(enable, "Enable AD1889 soundcard.");
  
  static char *ac97_quirk[SNDRV_CARDS];
  module_param_array(ac97_quirk, charp, NULL, 0444);
  MODULE_PARM_DESC(ac97_quirk, "AC'97 workaround for strange hardware.");
  
  #define DEVNAME "ad1889"
  #define PFX	DEVNAME ": "
  
  /* keep track of some hw registers */
  struct ad1889_register_state {
  	u16 reg;	/* reg setup */
  	u32 addr;	/* dma base address */
  	unsigned long size;	/* DMA buffer size */
  };
  
  struct snd_ad1889 {
  	struct snd_card *card;
  	struct pci_dev *pci;
  
  	int irq;
  	unsigned long bar;
  	void __iomem *iobase;
  
  	struct snd_ac97 *ac97;
  	struct snd_ac97_bus *ac97_bus;
  	struct snd_pcm *pcm;
  	struct snd_info_entry *proc;
  
  	struct snd_pcm_substream *psubs;
  	struct snd_pcm_substream *csubs;
  
  	/* playback register state */
  	struct ad1889_register_state wave;
  	struct ad1889_register_state ramc;
  
  	spinlock_t lock;
  };
  
  static inline u16
  ad1889_readw(struct snd_ad1889 *chip, unsigned reg)
  {
  	return readw(chip->iobase + reg);
  }
  
  static inline void
  ad1889_writew(struct snd_ad1889 *chip, unsigned reg, u16 val)
  {
  	writew(val, chip->iobase + reg);
  }
  
  static inline u32
  ad1889_readl(struct snd_ad1889 *chip, unsigned reg)
  {
  	return readl(chip->iobase + reg);
  }
  
  static inline void
  ad1889_writel(struct snd_ad1889 *chip, unsigned reg, u32 val)
  {
  	writel(val, chip->iobase + reg);
  }
  
  static inline void
  ad1889_unmute(struct snd_ad1889 *chip)
  {
  	u16 st;
  	st = ad1889_readw(chip, AD_DS_WADA) & 
  		~(AD_DS_WADA_RWAM | AD_DS_WADA_LWAM);
  	ad1889_writew(chip, AD_DS_WADA, st);
  	ad1889_readw(chip, AD_DS_WADA);
  }
  
  static inline void
  ad1889_mute(struct snd_ad1889 *chip)
  {
  	u16 st;
  	st = ad1889_readw(chip, AD_DS_WADA) | AD_DS_WADA_RWAM | AD_DS_WADA_LWAM;
  	ad1889_writew(chip, AD_DS_WADA, st);
  	ad1889_readw(chip, AD_DS_WADA);
  }
  
  static inline void
  ad1889_load_adc_buffer_address(struct snd_ad1889 *chip, u32 address)
  {
  	ad1889_writel(chip, AD_DMA_ADCBA, address);
  	ad1889_writel(chip, AD_DMA_ADCCA, address);
  }
  
  static inline void
  ad1889_load_adc_buffer_count(struct snd_ad1889 *chip, u32 count)
  {
  	ad1889_writel(chip, AD_DMA_ADCBC, count);
  	ad1889_writel(chip, AD_DMA_ADCCC, count);
  }
  
  static inline void
  ad1889_load_adc_interrupt_count(struct snd_ad1889 *chip, u32 count)
  {
  	ad1889_writel(chip, AD_DMA_ADCIB, count);
  	ad1889_writel(chip, AD_DMA_ADCIC, count);
  }
  
  static inline void
  ad1889_load_wave_buffer_address(struct snd_ad1889 *chip, u32 address)
  {
  	ad1889_writel(chip, AD_DMA_WAVBA, address);
  	ad1889_writel(chip, AD_DMA_WAVCA, address);
  }
  
  static inline void
  ad1889_load_wave_buffer_count(struct snd_ad1889 *chip, u32 count)
  {
  	ad1889_writel(chip, AD_DMA_WAVBC, count);
  	ad1889_writel(chip, AD_DMA_WAVCC, count);
  }
  
  static inline void
  ad1889_load_wave_interrupt_count(struct snd_ad1889 *chip, u32 count)
  {
  	ad1889_writel(chip, AD_DMA_WAVIB, count);
  	ad1889_writel(chip, AD_DMA_WAVIC, count);
  }
  
  static void
  ad1889_channel_reset(struct snd_ad1889 *chip, unsigned int channel)
  {
  	u16 reg;
  	
  	if (channel & AD_CHAN_WAV) {
  		/* Disable wave channel */
  		reg = ad1889_readw(chip, AD_DS_WSMC) & ~AD_DS_WSMC_WAEN;
  		ad1889_writew(chip, AD_DS_WSMC, reg);
  		chip->wave.reg = reg;
  		
  		/* disable IRQs */
  		reg = ad1889_readw(chip, AD_DMA_WAV);
  		reg &= AD_DMA_IM_DIS;
  		reg &= ~AD_DMA_LOOP;
  		ad1889_writew(chip, AD_DMA_WAV, reg);
  
  		/* clear IRQ and address counters and pointers */
  		ad1889_load_wave_buffer_address(chip, 0x0);
  		ad1889_load_wave_buffer_count(chip, 0x0);
  		ad1889_load_wave_interrupt_count(chip, 0x0);
  
  		/* flush */
  		ad1889_readw(chip, AD_DMA_WAV);
  	}
  	
  	if (channel & AD_CHAN_ADC) {
  		/* Disable ADC channel */
  		reg = ad1889_readw(chip, AD_DS_RAMC) & ~AD_DS_RAMC_ADEN;
  		ad1889_writew(chip, AD_DS_RAMC, reg);
  		chip->ramc.reg = reg;
  
  		reg = ad1889_readw(chip, AD_DMA_ADC);
  		reg &= AD_DMA_IM_DIS;
  		reg &= ~AD_DMA_LOOP;
  		ad1889_writew(chip, AD_DMA_ADC, reg);
  	
  		ad1889_load_adc_buffer_address(chip, 0x0);
  		ad1889_load_adc_buffer_count(chip, 0x0);
  		ad1889_load_adc_interrupt_count(chip, 0x0);
  
  		/* flush */
  		ad1889_readw(chip, AD_DMA_ADC);
  	}
  }
  
  static u16
  snd_ad1889_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
  {
  	struct snd_ad1889 *chip = ac97->private_data;
  	return ad1889_readw(chip, AD_AC97_BASE + reg);
  }
  
  static void
  snd_ad1889_ac97_write(struct snd_ac97 *ac97, unsigned short reg, unsigned short val)
  {
  	struct snd_ad1889 *chip = ac97->private_data;
  	ad1889_writew(chip, AD_AC97_BASE + reg, val);
  }
  
  static int
  snd_ad1889_ac97_ready(struct snd_ad1889 *chip)
  {
  	int retry = 400; /* average needs 352 msec */
  	
  	while (!(ad1889_readw(chip, AD_AC97_ACIC) & AD_AC97_ACIC_ACRDY) 
  			&& --retry)
  		mdelay(1);
  	if (!retry) {
  		dev_err(chip->card->dev, "[%s] Link is not ready.
  ",
  			__func__);
  		return -EIO;
  	}
  	dev_dbg(chip->card->dev, "[%s] ready after %d ms
  ", __func__, 400 - retry);
  
  	return 0;
  }
  
  static int 
  snd_ad1889_hw_params(struct snd_pcm_substream *substream,
  			struct snd_pcm_hw_params *hw_params)
  {
  	return snd_pcm_lib_malloc_pages(substream, 
  					params_buffer_bytes(hw_params));
  }
  
  static int
  snd_ad1889_hw_free(struct snd_pcm_substream *substream)
  {
  	return snd_pcm_lib_free_pages(substream);
  }
  
  static struct snd_pcm_hardware snd_ad1889_playback_hw = {
  	.info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
  		SNDRV_PCM_INFO_MMAP_VALID | SNDRV_PCM_INFO_BLOCK_TRANSFER,
  	.formats = SNDRV_PCM_FMTBIT_S16_LE,
  	.rates = SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000,
  	.rate_min = 8000,	/* docs say 7000, but we're lazy */
  	.rate_max = 48000,
  	.channels_min = 1,
  	.channels_max = 2,
  	.buffer_bytes_max = BUFFER_BYTES_MAX,
  	.period_bytes_min = PERIOD_BYTES_MIN,
  	.period_bytes_max = PERIOD_BYTES_MAX,
  	.periods_min = PERIODS_MIN,
  	.periods_max = PERIODS_MAX,
  	/*.fifo_size = 0,*/
  };
  
  static struct snd_pcm_hardware snd_ad1889_capture_hw = {
  	.info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
  		SNDRV_PCM_INFO_MMAP_VALID | SNDRV_PCM_INFO_BLOCK_TRANSFER,
  	.formats = SNDRV_PCM_FMTBIT_S16_LE,
  	.rates = SNDRV_PCM_RATE_48000,
  	.rate_min = 48000,	/* docs say we could to VSR, but we're lazy */
  	.rate_max = 48000,
  	.channels_min = 1,
  	.channels_max = 2,
  	.buffer_bytes_max = BUFFER_BYTES_MAX,
  	.period_bytes_min = PERIOD_BYTES_MIN,
  	.period_bytes_max = PERIOD_BYTES_MAX,
  	.periods_min = PERIODS_MIN,
  	.periods_max = PERIODS_MAX,
  	/*.fifo_size = 0,*/
  };
  
  static int
  snd_ad1889_playback_open(struct snd_pcm_substream *ss)
  {
  	struct snd_ad1889 *chip = snd_pcm_substream_chip(ss);
  	struct snd_pcm_runtime *rt = ss->runtime;
  
  	chip->psubs = ss;
  	rt->hw = snd_ad1889_playback_hw;
  
  	return 0;
  }
  
  static int
  snd_ad1889_capture_open(struct snd_pcm_substream *ss)
  {
  	struct snd_ad1889 *chip = snd_pcm_substream_chip(ss);
  	struct snd_pcm_runtime *rt = ss->runtime;
  
  	chip->csubs = ss;
  	rt->hw = snd_ad1889_capture_hw;
  
  	return 0;
  }
  
  static int
  snd_ad1889_playback_close(struct snd_pcm_substream *ss)
  {
  	struct snd_ad1889 *chip = snd_pcm_substream_chip(ss);
  	chip->psubs = NULL;
  	return 0;
  }
  
  static int
  snd_ad1889_capture_close(struct snd_pcm_substream *ss)
  {
  	struct snd_ad1889 *chip = snd_pcm_substream_chip(ss);
  	chip->csubs = NULL;
  	return 0;
  }
  
  static int
  snd_ad1889_playback_prepare(struct snd_pcm_substream *ss)
  {
  	struct snd_ad1889 *chip = snd_pcm_substream_chip(ss);
  	struct snd_pcm_runtime *rt = ss->runtime;
  	unsigned int size = snd_pcm_lib_buffer_bytes(ss);
  	unsigned int count = snd_pcm_lib_period_bytes(ss);
  	u16 reg;
  
  	ad1889_channel_reset(chip, AD_CHAN_WAV);
  
  	reg = ad1889_readw(chip, AD_DS_WSMC);
  	
  	/* Mask out 16-bit / Stereo */
  	reg &= ~(AD_DS_WSMC_WA16 | AD_DS_WSMC_WAST);
  
  	if (snd_pcm_format_width(rt->format) == 16)
  		reg |= AD_DS_WSMC_WA16;
  
  	if (rt->channels > 1)
  		reg |= AD_DS_WSMC_WAST;
  
  	/* let's make sure we don't clobber ourselves */
  	spin_lock_irq(&chip->lock);
  	
  	chip->wave.size = size;
  	chip->wave.reg = reg;
  	chip->wave.addr = rt->dma_addr;
  
  	ad1889_writew(chip, AD_DS_WSMC, chip->wave.reg);
  	
  	/* Set sample rates on the codec */
  	ad1889_writew(chip, AD_DS_WAS, rt->rate);
  
  	/* Set up DMA */
  	ad1889_load_wave_buffer_address(chip, chip->wave.addr);
  	ad1889_load_wave_buffer_count(chip, size);
  	ad1889_load_wave_interrupt_count(chip, count);
  
  	/* writes flush */
  	ad1889_readw(chip, AD_DS_WSMC);
  	
  	spin_unlock_irq(&chip->lock);
  	
  	dev_dbg(chip->card->dev,
  		"prepare playback: addr = 0x%x, count = %u, size = %u, reg = 0x%x, rate = %u
  ",
  		chip->wave.addr, count, size, reg, rt->rate);
  	return 0;
  }
  
  static int
  snd_ad1889_capture_prepare(struct snd_pcm_substream *ss)
  {
  	struct snd_ad1889 *chip = snd_pcm_substream_chip(ss);
  	struct snd_pcm_runtime *rt = ss->runtime;
  	unsigned int size = snd_pcm_lib_buffer_bytes(ss);
  	unsigned int count = snd_pcm_lib_period_bytes(ss);
  	u16 reg;
  
  	ad1889_channel_reset(chip, AD_CHAN_ADC);
  	
  	reg = ad1889_readw(chip, AD_DS_RAMC);
  
  	/* Mask out 16-bit / Stereo */
  	reg &= ~(AD_DS_RAMC_AD16 | AD_DS_RAMC_ADST);
  
  	if (snd_pcm_format_width(rt->format) == 16)
  		reg |= AD_DS_RAMC_AD16;
  
  	if (rt->channels > 1)
  		reg |= AD_DS_RAMC_ADST;
  
  	/* let's make sure we don't clobber ourselves */
  	spin_lock_irq(&chip->lock);
  	
  	chip->ramc.size = size;
  	chip->ramc.reg = reg;
  	chip->ramc.addr = rt->dma_addr;
  
  	ad1889_writew(chip, AD_DS_RAMC, chip->ramc.reg);
  
  	/* Set up DMA */
  	ad1889_load_adc_buffer_address(chip, chip->ramc.addr);
  	ad1889_load_adc_buffer_count(chip, size);
  	ad1889_load_adc_interrupt_count(chip, count);
  
  	/* writes flush */
  	ad1889_readw(chip, AD_DS_RAMC);
  	
  	spin_unlock_irq(&chip->lock);
  	
  	dev_dbg(chip->card->dev,
  		"prepare capture: addr = 0x%x, count = %u, size = %u, reg = 0x%x, rate = %u
  ",
  		chip->ramc.addr, count, size, reg, rt->rate);
  	return 0;
  }
  
  /* this is called in atomic context with IRQ disabled.
     Must be as fast as possible and not sleep.
     DMA should be *triggered* by this call.
     The WSMC "WAEN" bit triggers DMA Wave On/Off */
  static int
  snd_ad1889_playback_trigger(struct snd_pcm_substream *ss, int cmd)
  {
  	u16 wsmc;
  	struct snd_ad1889 *chip = snd_pcm_substream_chip(ss);
  	
  	wsmc = ad1889_readw(chip, AD_DS_WSMC);
  
  	switch (cmd) {
  	case SNDRV_PCM_TRIGGER_START:
  		/* enable DMA loop & interrupts */
  		ad1889_writew(chip, AD_DMA_WAV, AD_DMA_LOOP | AD_DMA_IM_CNT);
  		wsmc |= AD_DS_WSMC_WAEN;
  		/* 1 to clear CHSS bit */
  		ad1889_writel(chip, AD_DMA_CHSS, AD_DMA_CHSS_WAVS);
  		ad1889_unmute(chip);
  		break;
  	case SNDRV_PCM_TRIGGER_STOP:
  		ad1889_mute(chip);
  		wsmc &= ~AD_DS_WSMC_WAEN;
  		break;
  	default:
  		snd_BUG();
  		return -EINVAL;
  	}
  	
  	chip->wave.reg = wsmc;
  	ad1889_writew(chip, AD_DS_WSMC, wsmc);	
  	ad1889_readw(chip, AD_DS_WSMC);	/* flush */
  
  	/* reset the chip when STOP - will disable IRQs */
  	if (cmd == SNDRV_PCM_TRIGGER_STOP)
  		ad1889_channel_reset(chip, AD_CHAN_WAV);
  
  	return 0;
  }
  
  /* this is called in atomic context with IRQ disabled.
     Must be as fast as possible and not sleep.
     DMA should be *triggered* by this call.
     The RAMC "ADEN" bit triggers DMA ADC On/Off */
  static int
  snd_ad1889_capture_trigger(struct snd_pcm_substream *ss, int cmd)
  {
  	u16 ramc;
  	struct snd_ad1889 *chip = snd_pcm_substream_chip(ss);
  
  	ramc = ad1889_readw(chip, AD_DS_RAMC);
  	
  	switch (cmd) {
  	case SNDRV_PCM_TRIGGER_START:
  		/* enable DMA loop & interrupts */
  		ad1889_writew(chip, AD_DMA_ADC, AD_DMA_LOOP | AD_DMA_IM_CNT);
  		ramc |= AD_DS_RAMC_ADEN;
  		/* 1 to clear CHSS bit */
  		ad1889_writel(chip, AD_DMA_CHSS, AD_DMA_CHSS_ADCS);
  		break;
  	case SNDRV_PCM_TRIGGER_STOP:
  		ramc &= ~AD_DS_RAMC_ADEN;
  		break;
  	default:
  		return -EINVAL;
  	}
  	
  	chip->ramc.reg = ramc;
  	ad1889_writew(chip, AD_DS_RAMC, ramc);	
  	ad1889_readw(chip, AD_DS_RAMC);	/* flush */
  	
  	/* reset the chip when STOP - will disable IRQs */
  	if (cmd == SNDRV_PCM_TRIGGER_STOP)
  		ad1889_channel_reset(chip, AD_CHAN_ADC);
  		
  	return 0;
  }
  
  /* Called in atomic context with IRQ disabled */
  static snd_pcm_uframes_t
  snd_ad1889_playback_pointer(struct snd_pcm_substream *ss)
  {
  	size_t ptr = 0;
  	struct snd_ad1889 *chip = snd_pcm_substream_chip(ss);
  
  	if (unlikely(!(chip->wave.reg & AD_DS_WSMC_WAEN)))
  		return 0;
  
  	ptr = ad1889_readl(chip, AD_DMA_WAVCA);
  	ptr -= chip->wave.addr;
  	
  	if (snd_BUG_ON(ptr >= chip->wave.size))
  		return 0;
  	
  	return bytes_to_frames(ss->runtime, ptr);
  }
  
  /* Called in atomic context with IRQ disabled */
  static snd_pcm_uframes_t
  snd_ad1889_capture_pointer(struct snd_pcm_substream *ss)
  {
  	size_t ptr = 0;
  	struct snd_ad1889 *chip = snd_pcm_substream_chip(ss);
  
  	if (unlikely(!(chip->ramc.reg & AD_DS_RAMC_ADEN)))
  		return 0;
  
  	ptr = ad1889_readl(chip, AD_DMA_ADCCA);
  	ptr -= chip->ramc.addr;
  
  	if (snd_BUG_ON(ptr >= chip->ramc.size))
  		return 0;
  	
  	return bytes_to_frames(ss->runtime, ptr);
  }
  
  static struct snd_pcm_ops snd_ad1889_playback_ops = {
  	.open = snd_ad1889_playback_open,
  	.close = snd_ad1889_playback_close,
  	.ioctl = snd_pcm_lib_ioctl,
  	.hw_params = snd_ad1889_hw_params,
  	.hw_free = snd_ad1889_hw_free,
  	.prepare = snd_ad1889_playback_prepare,
  	.trigger = snd_ad1889_playback_trigger,
  	.pointer = snd_ad1889_playback_pointer, 
  };
  
  static struct snd_pcm_ops snd_ad1889_capture_ops = {
  	.open = snd_ad1889_capture_open,
  	.close = snd_ad1889_capture_close,
  	.ioctl = snd_pcm_lib_ioctl,
  	.hw_params = snd_ad1889_hw_params,
  	.hw_free = snd_ad1889_hw_free,
  	.prepare = snd_ad1889_capture_prepare,
  	.trigger = snd_ad1889_capture_trigger,
  	.pointer = snd_ad1889_capture_pointer, 
  };
  
  static irqreturn_t
  snd_ad1889_interrupt(int irq, void *dev_id)
  {
  	unsigned long st;
  	struct snd_ad1889 *chip = dev_id;
  
  	st = ad1889_readl(chip, AD_DMA_DISR);
  
  	/* clear ISR */
  	ad1889_writel(chip, AD_DMA_DISR, st);
  
  	st &= AD_INTR_MASK;
  
  	if (unlikely(!st))
  		return IRQ_NONE;
  
  	if (st & (AD_DMA_DISR_PMAI|AD_DMA_DISR_PTAI))
  		dev_dbg(chip->card->dev,
  			"Unexpected master or target abort interrupt!
  ");
  
  	if ((st & AD_DMA_DISR_WAVI) && chip->psubs)
  		snd_pcm_period_elapsed(chip->psubs);
  	if ((st & AD_DMA_DISR_ADCI) && chip->csubs)
  		snd_pcm_period_elapsed(chip->csubs);
  
  	return IRQ_HANDLED;
  }
  
  static int
  snd_ad1889_pcm_init(struct snd_ad1889 *chip, int device)
  {
  	int err;
  	struct snd_pcm *pcm;
  
  	err = snd_pcm_new(chip->card, chip->card->driver, device, 1, 1, &pcm);
  	if (err < 0)
  		return err;
  
  	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, 
  			&snd_ad1889_playback_ops);
  	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE,
  			&snd_ad1889_capture_ops);
  
  	pcm->private_data = chip;
  	pcm->info_flags = 0;
  	strcpy(pcm->name, chip->card->shortname);
  	
  	chip->pcm = pcm;
  	chip->psubs = NULL;
  	chip->csubs = NULL;
  
  	err = snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
  						snd_dma_pci_data(chip->pci),
  						BUFFER_BYTES_MAX / 2,
  						BUFFER_BYTES_MAX);
  
  	if (err < 0) {
  		dev_err(chip->card->dev, "buffer allocation error: %d
  ", err);
  		return err;
  	}
  	
  	return 0;
  }
  
  static void
  snd_ad1889_proc_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer)
  {
  	struct snd_ad1889 *chip = entry->private_data;
  	u16 reg;
  	int tmp;
  
  	reg = ad1889_readw(chip, AD_DS_WSMC);
  	snd_iprintf(buffer, "Wave output: %s
  ",
  			(reg & AD_DS_WSMC_WAEN) ? "enabled" : "disabled");
  	snd_iprintf(buffer, "Wave Channels: %s
  ",
  			(reg & AD_DS_WSMC_WAST) ? "stereo" : "mono");
  	snd_iprintf(buffer, "Wave Quality: %d-bit linear
  ",
  			(reg & AD_DS_WSMC_WA16) ? 16 : 8);
  	
  	/* WARQ is at offset 12 */
  	tmp = (reg & AD_DS_WSMC_WARQ) ?
  		((((reg & AD_DS_WSMC_WARQ) >> 12) & 0x01) ? 12 : 18) : 4;
  	tmp /= (reg & AD_DS_WSMC_WAST) ? 2 : 1;
  	
  	snd_iprintf(buffer, "Wave FIFO: %d %s words
  
  ", tmp,
  			(reg & AD_DS_WSMC_WAST) ? "stereo" : "mono");
  				
  	
  	snd_iprintf(buffer, "Synthesis output: %s
  ",
  			reg & AD_DS_WSMC_SYEN ? "enabled" : "disabled");
  	
  	/* SYRQ is at offset 4 */
  	tmp = (reg & AD_DS_WSMC_SYRQ) ?
  		((((reg & AD_DS_WSMC_SYRQ) >> 4) & 0x01) ? 12 : 18) : 4;
  	tmp /= (reg & AD_DS_WSMC_WAST) ? 2 : 1;
  	
  	snd_iprintf(buffer, "Synthesis FIFO: %d %s words
  
  ", tmp,
  			(reg & AD_DS_WSMC_WAST) ? "stereo" : "mono");
  
  	reg = ad1889_readw(chip, AD_DS_RAMC);
  	snd_iprintf(buffer, "ADC input: %s
  ",
  			(reg & AD_DS_RAMC_ADEN) ? "enabled" : "disabled");
  	snd_iprintf(buffer, "ADC Channels: %s
  ",
  			(reg & AD_DS_RAMC_ADST) ? "stereo" : "mono");
  	snd_iprintf(buffer, "ADC Quality: %d-bit linear
  ",
  			(reg & AD_DS_RAMC_AD16) ? 16 : 8);
  	
  	/* ACRQ is at offset 4 */
  	tmp = (reg & AD_DS_RAMC_ACRQ) ?
  		((((reg & AD_DS_RAMC_ACRQ) >> 4) & 0x01) ? 12 : 18) : 4;
  	tmp /= (reg & AD_DS_RAMC_ADST) ? 2 : 1;
  	
  	snd_iprintf(buffer, "ADC FIFO: %d %s words
  
  ", tmp,
  			(reg & AD_DS_RAMC_ADST) ? "stereo" : "mono");
  	
  	snd_iprintf(buffer, "Resampler input: %s
  ",
  			reg & AD_DS_RAMC_REEN ? "enabled" : "disabled");
  			
  	/* RERQ is at offset 12 */
  	tmp = (reg & AD_DS_RAMC_RERQ) ?
  		((((reg & AD_DS_RAMC_RERQ) >> 12) & 0x01) ? 12 : 18) : 4;
  	tmp /= (reg & AD_DS_RAMC_ADST) ? 2 : 1;
  	
  	snd_iprintf(buffer, "Resampler FIFO: %d %s words
  
  ", tmp,
  			(reg & AD_DS_WSMC_WAST) ? "stereo" : "mono");
  				
  	
  	/* doc says LSB represents -1.5dB, but the max value (-94.5dB)
  	suggests that LSB is -3dB, which is more coherent with the logarithmic
  	nature of the dB scale */
  	reg = ad1889_readw(chip, AD_DS_WADA);
  	snd_iprintf(buffer, "Left: %s, -%d dB
  ",
  			(reg & AD_DS_WADA_LWAM) ? "mute" : "unmute",
  			((reg & AD_DS_WADA_LWAA) >> 8) * 3);
  	reg = ad1889_readw(chip, AD_DS_WADA);
  	snd_iprintf(buffer, "Right: %s, -%d dB
  ",
  			(reg & AD_DS_WADA_RWAM) ? "mute" : "unmute",
  			(reg & AD_DS_WADA_RWAA) * 3);
  	
  	reg = ad1889_readw(chip, AD_DS_WAS);
  	snd_iprintf(buffer, "Wave samplerate: %u Hz
  ", reg);
  	reg = ad1889_readw(chip, AD_DS_RES);
  	snd_iprintf(buffer, "Resampler samplerate: %u Hz
  ", reg);
  }
  
  static void
  snd_ad1889_proc_init(struct snd_ad1889 *chip)
  {
  	struct snd_info_entry *entry;
  
  	if (!snd_card_proc_new(chip->card, chip->card->driver, &entry))
  		snd_info_set_text_ops(entry, chip, snd_ad1889_proc_read);
  }
  
  static const struct ac97_quirk ac97_quirks[] = {
  	{
  		.subvendor = 0x11d4,	/* AD */
  		.subdevice = 0x1889,	/* AD1889 */
  		.codec_id = AC97_ID_AD1819,
  		.name = "AD1889",
  		.type = AC97_TUNE_HP_ONLY
  	},
  	{ } /* terminator */
  };
  
  static void
  snd_ad1889_ac97_xinit(struct snd_ad1889 *chip)
  {
  	u16 reg;
  
  	reg = ad1889_readw(chip, AD_AC97_ACIC);
  	reg |= AD_AC97_ACIC_ACRD;		/* Reset Disable */
  	ad1889_writew(chip, AD_AC97_ACIC, reg);
  	ad1889_readw(chip, AD_AC97_ACIC);	/* flush posted write */
  	udelay(10);
  	/* Interface Enable */
  	reg |= AD_AC97_ACIC_ACIE;
  	ad1889_writew(chip, AD_AC97_ACIC, reg);
  	
  	snd_ad1889_ac97_ready(chip);
  
  	/* Audio Stream Output | Variable Sample Rate Mode */
  	reg = ad1889_readw(chip, AD_AC97_ACIC);
  	reg |= AD_AC97_ACIC_ASOE | AD_AC97_ACIC_VSRM;
  	ad1889_writew(chip, AD_AC97_ACIC, reg);
  	ad1889_readw(chip, AD_AC97_ACIC); /* flush posted write */
  
  }
  
  static void
  snd_ad1889_ac97_bus_free(struct snd_ac97_bus *bus)
  {
  	struct snd_ad1889 *chip = bus->private_data;
  	chip->ac97_bus = NULL;
  }
  
  static void
  snd_ad1889_ac97_free(struct snd_ac97 *ac97)
  {
  	struct snd_ad1889 *chip = ac97->private_data;
  	chip->ac97 = NULL;
  }
  
  static int
  snd_ad1889_ac97_init(struct snd_ad1889 *chip, const char *quirk_override)
  {
  	int err;
  	struct snd_ac97_template ac97;
  	static struct snd_ac97_bus_ops ops = {
  		.write = snd_ad1889_ac97_write,
  		.read = snd_ad1889_ac97_read,
  	};
  
  	/* doing that here, it works. */
  	snd_ad1889_ac97_xinit(chip);
  
  	err = snd_ac97_bus(chip->card, 0, &ops, chip, &chip->ac97_bus);
  	if (err < 0)
  		return err;
  	
  	chip->ac97_bus->private_free = snd_ad1889_ac97_bus_free;
  
  	memset(&ac97, 0, sizeof(ac97));
  	ac97.private_data = chip;
  	ac97.private_free = snd_ad1889_ac97_free;
  	ac97.pci = chip->pci;
  
  	err = snd_ac97_mixer(chip->ac97_bus, &ac97, &chip->ac97);
  	if (err < 0)
  		return err;
  		
  	snd_ac97_tune_hardware(chip->ac97, ac97_quirks, quirk_override);
  	
  	return 0;
  }
  
  static int
  snd_ad1889_free(struct snd_ad1889 *chip)
  {
  	if (chip->irq < 0)
  		goto skip_hw;
  
  	spin_lock_irq(&chip->lock);
  
  	ad1889_mute(chip);
  
  	/* Turn off interrupt on count and zero DMA registers */
  	ad1889_channel_reset(chip, AD_CHAN_WAV | AD_CHAN_ADC);
  
  	/* clear DISR. If we don't, we'd better jump off the Eiffel Tower */
  	ad1889_writel(chip, AD_DMA_DISR, AD_DMA_DISR_PTAI | AD_DMA_DISR_PMAI);
  	ad1889_readl(chip, AD_DMA_DISR);	/* flush, dammit! */
  
  	spin_unlock_irq(&chip->lock);
  
  	if (chip->irq >= 0)
  		free_irq(chip->irq, chip);
  
  skip_hw:
  	iounmap(chip->iobase);
  	pci_release_regions(chip->pci);
  	pci_disable_device(chip->pci);
  	kfree(chip);
  	return 0;
  }
  
  static int
  snd_ad1889_dev_free(struct snd_device *device) 
  {
  	struct snd_ad1889 *chip = device->device_data;
  	return snd_ad1889_free(chip);
  }
  
  static int
  snd_ad1889_init(struct snd_ad1889 *chip) 
  {
  	ad1889_writew(chip, AD_DS_CCS, AD_DS_CCS_CLKEN); /* turn on clock */
  	ad1889_readw(chip, AD_DS_CCS);	/* flush posted write */
  
  	mdelay(10);
  
  	/* enable Master and Target abort interrupts */
  	ad1889_writel(chip, AD_DMA_DISR, AD_DMA_DISR_PMAE | AD_DMA_DISR_PTAE);
  
  	return 0;
  }
  
  static int
  snd_ad1889_create(struct snd_card *card,
  		  struct pci_dev *pci,
  		  struct snd_ad1889 **rchip)
  {
  	int err;
  
  	struct snd_ad1889 *chip;
  	static struct snd_device_ops ops = {
  		.dev_free = snd_ad1889_dev_free,
  	};
  
  	*rchip = NULL;
  
  	if ((err = pci_enable_device(pci)) < 0)
  		return err;
  
  	/* check PCI availability (32bit DMA) */
  	if (dma_set_mask(&pci->dev, DMA_BIT_MASK(32)) < 0 ||
  	    dma_set_coherent_mask(&pci->dev, DMA_BIT_MASK(32)) < 0) {
  		dev_err(card->dev, "error setting 32-bit DMA mask.
  ");
  		pci_disable_device(pci);
  		return -ENXIO;
  	}
  
  	/* allocate chip specific data with zero-filled memory */
  	if ((chip = kzalloc(sizeof(*chip), GFP_KERNEL)) == NULL) {
  		pci_disable_device(pci);
  		return -ENOMEM;
  	}
  
  	chip->card = card;
  	card->private_data = chip;
  	chip->pci = pci;
  	chip->irq = -1;
  
  	/* (1) PCI resource allocation */
  	if ((err = pci_request_regions(pci, card->driver)) < 0)
  		goto free_and_ret;
  
  	chip->bar = pci_resource_start(pci, 0);
  	chip->iobase = pci_ioremap_bar(pci, 0);
  	if (chip->iobase == NULL) {
  		dev_err(card->dev, "unable to reserve region.
  ");
  		err = -EBUSY;
  		goto free_and_ret;
  	}
  	
  	pci_set_master(pci);
  
  	spin_lock_init(&chip->lock);	/* only now can we call ad1889_free */
  
  	if (request_irq(pci->irq, snd_ad1889_interrupt,
  			IRQF_SHARED, KBUILD_MODNAME, chip)) {
  		dev_err(card->dev, "cannot obtain IRQ %d
  ", pci->irq);
  		snd_ad1889_free(chip);
  		return -EBUSY;
  	}
  
  	chip->irq = pci->irq;
  	synchronize_irq(chip->irq);
  
  	/* (2) initialization of the chip hardware */
  	if ((err = snd_ad1889_init(chip)) < 0) {
  		snd_ad1889_free(chip);
  		return err;
  	}
  
  	if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops)) < 0) {
  		snd_ad1889_free(chip);
  		return err;
  	}
  
  	*rchip = chip;
  
  	return 0;
  
  free_and_ret:
  	kfree(chip);
  	pci_disable_device(pci);
  
  	return err;
  }
  
  static int
  snd_ad1889_probe(struct pci_dev *pci,
  		 const struct pci_device_id *pci_id)
  {
  	int err;
  	static int devno;
  	struct snd_card *card;
  	struct snd_ad1889 *chip;
  
  	/* (1) */
  	if (devno >= SNDRV_CARDS)
  		return -ENODEV;
  	if (!enable[devno]) {
  		devno++;
  		return -ENOENT;
  	}
  
  	/* (2) */
  	err = snd_card_new(&pci->dev, index[devno], id[devno], THIS_MODULE,
  			   0, &card);
  	/* XXX REVISIT: we can probably allocate chip in this call */
  	if (err < 0)
  		return err;
  
  	strcpy(card->driver, "AD1889");
  	strcpy(card->shortname, "Analog Devices AD1889");
  
  	/* (3) */
  	err = snd_ad1889_create(card, pci, &chip);
  	if (err < 0)
  		goto free_and_ret;
  
  	/* (4) */
  	sprintf(card->longname, "%s at 0x%lx irq %i",
  		card->shortname, chip->bar, chip->irq);
  
  	/* (5) */
  	/* register AC97 mixer */
  	err = snd_ad1889_ac97_init(chip, ac97_quirk[devno]);
  	if (err < 0)
  		goto free_and_ret;
  	
  	err = snd_ad1889_pcm_init(chip, 0);
  	if (err < 0)
  		goto free_and_ret;
  
  	/* register proc interface */
  	snd_ad1889_proc_init(chip);
  
  	/* (6) */
  	err = snd_card_register(card);
  	if (err < 0)
  		goto free_and_ret;
  
  	/* (7) */
  	pci_set_drvdata(pci, card);
  
  	devno++;
  	return 0;
  
  free_and_ret:
  	snd_card_free(card);
  	return err;
  }
  
  static void
  snd_ad1889_remove(struct pci_dev *pci)
  {
  	snd_card_free(pci_get_drvdata(pci));
  }
  
  static const struct pci_device_id snd_ad1889_ids[] = {
  	{ PCI_DEVICE(PCI_VENDOR_ID_ANALOG_DEVICES, PCI_DEVICE_ID_AD1889JS) },
  	{ 0, },
  };
  MODULE_DEVICE_TABLE(pci, snd_ad1889_ids);
  
  static struct pci_driver ad1889_pci_driver = {
  	.name = KBUILD_MODNAME,
  	.id_table = snd_ad1889_ids,
  	.probe = snd_ad1889_probe,
  	.remove = snd_ad1889_remove,
  };
  
  module_pci_driver(ad1889_pci_driver);