nm256.c

linux 内核源代码

static int
snd_nm256_capture_close(struct snd_pcm_substream *substream)
{
	struct nm256 *chip = snd_pcm_substream_chip(substream);

	snd_nm256_release_irq(chip);
	return 0;
}

/*
 * create a pcm instance
 */
static struct snd_pcm_ops snd_nm256_playback_ops = {
	.open =		snd_nm256_playback_open,
	.close =	snd_nm256_playback_close,
	.ioctl =	snd_pcm_lib_ioctl,
	.hw_params =	snd_nm256_pcm_hw_params,
	.prepare =	snd_nm256_pcm_prepare,
	.trigger =	snd_nm256_playback_trigger,
	.pointer =	snd_nm256_playback_pointer,
#ifndef __i386__
	.copy =		snd_nm256_playback_copy,
	.silence =	snd_nm256_playback_silence,
#endif
	.mmap =		snd_pcm_lib_mmap_iomem,
};

static struct snd_pcm_ops snd_nm256_capture_ops = {
	.open =		snd_nm256_capture_open,
	.close =	snd_nm256_capture_close,
	.ioctl =	snd_pcm_lib_ioctl,
	.hw_params =	snd_nm256_pcm_hw_params,
	.prepare =	snd_nm256_pcm_prepare,
	.trigger =	snd_nm256_capture_trigger,
	.pointer =	snd_nm256_capture_pointer,
#ifndef __i386__
	.copy =		snd_nm256_capture_copy,
#endif
	.mmap =		snd_pcm_lib_mmap_iomem,
};

static int __devinit
snd_nm256_pcm(struct nm256 *chip, int device)
{
	struct snd_pcm *pcm;
	int i, err;

	for (i = 0; i < 2; i++) {
		struct nm256_stream *s = &chip->streams[i];
		s->bufptr = chip->buffer + (s->buf - chip->buffer_start);
		s->bufptr_addr = chip->buffer_addr + (s->buf - chip->buffer_start);
	}

	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_nm256_playback_ops);
	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_nm256_capture_ops);

	pcm->private_data = chip;
	pcm->info_flags = 0;
	chip->pcm = pcm;

	return 0;
}


/* 
 * Initialize the hardware. 
 */
static void
snd_nm256_init_chip(struct nm256 *chip)
{
	/* Reset everything. */
	snd_nm256_writeb(chip, 0x0, 0x11);
	snd_nm256_writew(chip, 0x214, 0);
	/* stop sounds.. */
	//snd_nm256_playback_stop(chip);
	//snd_nm256_capture_stop(chip);
}


static irqreturn_t
snd_nm256_intr_check(struct nm256 *chip)
{
	if (chip->badintrcount++ > 1000) {
		/*
		 * I'm not sure if the best thing is to stop the card from
		 * playing or just release the interrupt (after all, we're in
		 * a bad situation, so doing fancy stuff may not be such a good
		 * idea).
		 *
		 * I worry about the card engine continuing to play noise
		 * over and over, however--that could become a very
		 * obnoxious problem.  And we know that when this usually
		 * happens things are fairly safe, it just means the user's
		 * inserted a PCMCIA card and someone's spamming us with IRQ 9s.
		 */
		if (chip->streams[SNDRV_PCM_STREAM_PLAYBACK].running)
			snd_nm256_playback_stop(chip);
		if (chip->streams[SNDRV_PCM_STREAM_CAPTURE].running)
			snd_nm256_capture_stop(chip);
		chip->badintrcount = 0;
		return IRQ_HANDLED;
	}
	return IRQ_NONE;
}

/* 
 * Handle a potential interrupt for the device referred to by DEV_ID. 
 *
 * I don't like the cut-n-paste job here either between the two routines,
 * but there are sufficient differences between the two interrupt handlers
 * that parameterizing it isn't all that great either.  (Could use a macro,
 * I suppose...yucky bleah.)
 */

static irqreturn_t
snd_nm256_interrupt(int irq, void *dev_id)
{
	struct nm256 *chip = dev_id;
	u16 status;
	u8 cbyte;

	status = snd_nm256_readw(chip, NM_INT_REG);

	/* Not ours. */
	if (status == 0)
		return snd_nm256_intr_check(chip);

	chip->badintrcount = 0;

	/* Rather boring; check for individual interrupts and process them. */

	spin_lock(&chip->reg_lock);
	if (status & NM_PLAYBACK_INT) {
		status &= ~NM_PLAYBACK_INT;
		NM_ACK_INT(chip, NM_PLAYBACK_INT);
		snd_nm256_playback_update(chip);
	}

	if (status & NM_RECORD_INT) {
		status &= ~NM_RECORD_INT;
		NM_ACK_INT(chip, NM_RECORD_INT);
		snd_nm256_capture_update(chip);
	}

	if (status & NM_MISC_INT_1) {
		status &= ~NM_MISC_INT_1;
		NM_ACK_INT(chip, NM_MISC_INT_1);
		snd_printd("NM256: Got misc interrupt #1\n");
		snd_nm256_writew(chip, NM_INT_REG, 0x8000);
		cbyte = snd_nm256_readb(chip, 0x400);
		snd_nm256_writeb(chip, 0x400, cbyte | 2);
	}

	if (status & NM_MISC_INT_2) {
		status &= ~NM_MISC_INT_2;
		NM_ACK_INT(chip, NM_MISC_INT_2);
		snd_printd("NM256: Got misc interrupt #2\n");
		cbyte = snd_nm256_readb(chip, 0x400);
		snd_nm256_writeb(chip, 0x400, cbyte & ~2);
	}

	/* Unknown interrupt. */
	if (status) {
		snd_printd("NM256: Fire in the hole! Unknown status 0x%x\n",
			   status);
		/* Pray. */
		NM_ACK_INT(chip, status);
	}

	spin_unlock(&chip->reg_lock);
	return IRQ_HANDLED;
}

/*
 * Handle a potential interrupt for the device referred to by DEV_ID.
 * This handler is for the 256ZX, and is very similar to the non-ZX
 * routine.
 */

static irqreturn_t
snd_nm256_interrupt_zx(int irq, void *dev_id)
{
	struct nm256 *chip = dev_id;
	u32 status;
	u8 cbyte;

	status = snd_nm256_readl(chip, NM_INT_REG);

	/* Not ours. */
	if (status == 0)
		return snd_nm256_intr_check(chip);

	chip->badintrcount = 0;

	/* Rather boring; check for individual interrupts and process them. */

	spin_lock(&chip->reg_lock);
	if (status & NM2_PLAYBACK_INT) {
		status &= ~NM2_PLAYBACK_INT;
		NM2_ACK_INT(chip, NM2_PLAYBACK_INT);
		snd_nm256_playback_update(chip);
	}

	if (status & NM2_RECORD_INT) {
		status &= ~NM2_RECORD_INT;
		NM2_ACK_INT(chip, NM2_RECORD_INT);
		snd_nm256_capture_update(chip);
	}

	if (status & NM2_MISC_INT_1) {
		status &= ~NM2_MISC_INT_1;
		NM2_ACK_INT(chip, NM2_MISC_INT_1);
		snd_printd("NM256: Got misc interrupt #1\n");
		cbyte = snd_nm256_readb(chip, 0x400);
		snd_nm256_writeb(chip, 0x400, cbyte | 2);
	}

	if (status & NM2_MISC_INT_2) {
		status &= ~NM2_MISC_INT_2;
		NM2_ACK_INT(chip, NM2_MISC_INT_2);
		snd_printd("NM256: Got misc interrupt #2\n");
		cbyte = snd_nm256_readb(chip, 0x400);
		snd_nm256_writeb(chip, 0x400, cbyte & ~2);
	}

	/* Unknown interrupt. */
	if (status) {
		snd_printd("NM256: Fire in the hole! Unknown status 0x%x\n",
			   status);
		/* Pray. */
		NM2_ACK_INT(chip, status);
	}

	spin_unlock(&chip->reg_lock);
	return IRQ_HANDLED;
}

/*
 * AC97 interface
 */

/*
 * Waits for the mixer to become ready to be written; returns a zero value
 * if it timed out.
 */
static int
snd_nm256_ac97_ready(struct nm256 *chip)
{
	int timeout = 10;
	u32 testaddr;
	u16 testb;

	testaddr = chip->mixer_status_offset;
	testb = chip->mixer_status_mask;

	/* 
	 * Loop around waiting for the mixer to become ready. 
	 */
	while (timeout-- > 0) {
		if ((snd_nm256_readw(chip, testaddr) & testb) == 0)
			return 1;
		udelay(100);
	}
	return 0;
}

/* 
 * Initial register values to be written to the AC97 mixer.
 * While most of these are identical to the reset values, we do this
 * so that we have most of the register contents cached--this avoids
 * reading from the mixer directly (which seems to be problematic,
 * probably due to ignorance).
 */

struct initialValues {
	unsigned short reg;
	unsigned short value;
};

static struct initialValues nm256_ac97_init_val[] =
{
	{ AC97_MASTER, 		0x8000 },
	{ AC97_HEADPHONE,	0x8000 },
	{ AC97_MASTER_MONO,	0x8000 },
	{ AC97_PC_BEEP,		0x8000 },
	{ AC97_PHONE,		0x8008 },
	{ AC97_MIC,		0x8000 },
	{ AC97_LINE,		0x8808 },
	{ AC97_CD,		0x8808 },
	{ AC97_VIDEO,		0x8808 },
	{ AC97_AUX,		0x8808 },
	{ AC97_PCM,		0x8808 },
	{ AC97_REC_SEL,		0x0000 },
	{ AC97_REC_GAIN,	0x0B0B },
	{ AC97_GENERAL_PURPOSE,	0x0000 },
	{ AC97_3D_CONTROL,	0x8000 }, 
	{ AC97_VENDOR_ID1, 	0x8384 },
	{ AC97_VENDOR_ID2,	0x7609 },
};

static int nm256_ac97_idx(unsigned short reg)
{
	int i;
	for (i = 0; i < ARRAY_SIZE(nm256_ac97_init_val); i++)
		if (nm256_ac97_init_val[i].reg == reg)
			return i;
	return -1;
}

/*
 * some nm256 easily crash when reading from mixer registers
 * thus we're treating it as a write-only mixer and cache the
 * written values
 */
static unsigned short
snd_nm256_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
{
	struct nm256 *chip = ac97->private_data;
	int idx = nm256_ac97_idx(reg);

	if (idx < 0)
		return 0;
	return chip->ac97_regs[idx];
}

/* 
 */
static void
snd_nm256_ac97_write(struct snd_ac97 *ac97,
		     unsigned short reg, unsigned short val)
{
	struct nm256 *chip = ac97->private_data;
	int tries = 2;
	int idx = nm256_ac97_idx(reg);
	u32 base;

	if (idx < 0)
		return;

	base = chip->mixer_base;

	snd_nm256_ac97_ready(chip);

	/* Wait for the write to take, too. */
	while (tries-- > 0) {
		snd_nm256_writew(chip, base + reg, val);
		msleep(1);  /* a little delay here seems better.. */
		if (snd_nm256_ac97_ready(chip)) {
			/* successful write: set cache */
			chip->ac97_regs[idx] = val;
			return;
		}
	}
	snd_printd("nm256: ac97 codec not ready..\n");
}

/* static resolution table */
static struct snd_ac97_res_table nm256_res_table[] = {
	{ AC97_MASTER, 0x1f1f },
	{ AC97_HEADPHONE, 0x1f1f },
	{ AC97_MASTER_MONO, 0x001f },
	{ AC97_PC_BEEP, 0x001f },
	{ AC97_PHONE, 0x001f },
	{ AC97_MIC, 0x001f },
	{ AC97_LINE, 0x1f1f },
	{ AC97_CD, 0x1f1f },
	{ AC97_VIDEO, 0x1f1f },
	{ AC97_AUX, 0x1f1f },
	{ AC97_PCM, 0x1f1f },
	{ AC97_REC_GAIN, 0x0f0f },
	{ } /* terminator */
};

/* initialize the ac97 into a known state */
static void
snd_nm256_ac97_reset(struct snd_ac97 *ac97)
{
	struct nm256 *chip = ac97->private_data;

	/* Reset the mixer.  'Tis magic!  */
	snd_nm256_writeb(chip, 0x6c0, 1);
	if (! chip->reset_workaround) {
		/* Dell latitude LS will lock up by this */
		snd_nm256_writeb(chip, 0x6cc, 0x87);
	}
	if (! chip->reset_workaround_2) {
		/* Dell latitude CSx will lock up by this */
		snd_nm256_writeb(chip, 0x6cc, 0x80);
		snd_nm256_writeb(chip, 0x6cc, 0x0);
	}
	if (! chip->in_resume) {
		int i;
		for (i = 0; i < ARRAY_SIZE(nm256_ac97_init_val); i++) {
			/* preload the cache, so as to avoid even a single
			 * read of the mixer regs
			 */
			snd_nm256_ac97_write(ac97, nm256_ac97_init_val[i].reg,
					     nm256_ac97_init_val[i].value);
		}
	}
}

/* create an ac97 mixer interface */
static int __devinit
snd_nm256_mixer(struct nm256 *chip)
{
	struct snd_ac97_bus *pbus;
	struct snd_ac97_template ac97;
	int err;
	static struct snd_ac97_bus_ops ops = {
		.reset = snd_nm256_ac97_reset,
		.write = snd_nm256_ac97_write,
		.read = snd_nm256_ac97_read,
	};

	chip->ac97_regs = kcalloc(sizeof(short),
				  ARRAY_SIZE(nm256_ac97_init_val), GFP_KERNEL);
	if (! chip->ac97_regs)
		return -ENOMEM;

	if ((err = snd_ac97_bus(chip->card, 0, &ops, NULL, &pbus)) < 0)
		return err;

	memset(&ac97, 0, sizeof(ac97));
	ac97.scaps = AC97_SCAP_AUDIO; /* we support audio! */
	ac97.private_data = chip;
	ac97.res_table = nm256_res_table;
	pbus->no_vra = 1;
	err = snd_ac97_mixer(pbus, &ac97, &chip->ac97);
	if (err < 0)
		return err;
	if (! (chip->ac97->id & (0xf0000000))) {
		/* looks like an invalid id */
		sprintf(chip->card->mixername, "%s AC97", chip->card->driver);
	}
	return 0;