ac97_codec.c

h内核

	snd_ac97_write(ac97, AC97_GPIO_POLARITY, 0xffff & ~(AC97_GPIO_LINE1_OH));
	snd_ac97_write(ac97, AC97_GPIO_STICKY, 0xffff);
	snd_ac97_write(ac97, AC97_GPIO_WAKEUP, 0x0);
	snd_ac97_write(ac97, AC97_MISC_AFE, 0x0);
	return 0;
}

static int snd_ac97_test_rate(ac97_t *ac97, int reg, int shadow_reg, int rate)
{
	unsigned short val;
	unsigned int tmp;

	tmp = ((unsigned int)rate * ac97->bus->clock) / 48000;
	snd_ac97_write_cache(ac97, reg, tmp & 0xffff);
	if (shadow_reg)
		snd_ac97_write_cache(ac97, shadow_reg, tmp & 0xffff);
	val = snd_ac97_read(ac97, reg);
	return val == (tmp & 0xffff);
}

static void snd_ac97_determine_rates(ac97_t *ac97, int reg, int shadow_reg, unsigned int *r_result)
{
	unsigned int result = 0;

	if (ac97->bus->no_vra) {
		*r_result = SNDRV_PCM_RATE_48000;
		if ((ac97->flags & AC97_DOUBLE_RATE) &&
		    reg == AC97_PCM_FRONT_DAC_RATE)
			*r_result |= SNDRV_PCM_RATE_96000;
		return;
	}

	if ((ac97->ext_id & AC97_EI_DRA) && reg == AC97_PCM_FRONT_DAC_RATE)
		snd_ac97_update_bits(ac97, AC97_EXTENDED_STATUS,
				     AC97_EA_DRA, 0);
	/* test a non-standard rate */
	if (snd_ac97_test_rate(ac97, reg, shadow_reg, 11000))
		result |= SNDRV_PCM_RATE_CONTINUOUS;
	/* let's try to obtain standard rates */
	if (snd_ac97_test_rate(ac97, reg, shadow_reg, 8000))
		result |= SNDRV_PCM_RATE_8000;
	if (snd_ac97_test_rate(ac97, reg, shadow_reg, 11025))
		result |= SNDRV_PCM_RATE_11025;
	if (snd_ac97_test_rate(ac97, reg, shadow_reg, 16000))
		result |= SNDRV_PCM_RATE_16000;
	if (snd_ac97_test_rate(ac97, reg, shadow_reg, 22050))
		result |= SNDRV_PCM_RATE_22050;
	if (snd_ac97_test_rate(ac97, reg, shadow_reg, 32000))
		result |= SNDRV_PCM_RATE_32000;
	if (snd_ac97_test_rate(ac97, reg, shadow_reg, 44100))
		result |= SNDRV_PCM_RATE_44100;
	if (snd_ac97_test_rate(ac97, reg, shadow_reg, 48000))
		result |= SNDRV_PCM_RATE_48000;
	if ((ac97->flags & AC97_DOUBLE_RATE) &&
	    reg == AC97_PCM_FRONT_DAC_RATE) {
		/* test standard double rates */
		snd_ac97_update_bits(ac97, AC97_EXTENDED_STATUS,
				     AC97_EA_DRA, AC97_EA_DRA);
		if (snd_ac97_test_rate(ac97, reg, shadow_reg, 64000 / 2))
			result |= SNDRV_PCM_RATE_64000;
		if (snd_ac97_test_rate(ac97, reg, shadow_reg, 88200 / 2))
			result |= SNDRV_PCM_RATE_88200;
		if (snd_ac97_test_rate(ac97, reg, shadow_reg, 96000 / 2))
			result |= SNDRV_PCM_RATE_96000;
		/* some codecs don't support variable double rates */
		if (!snd_ac97_test_rate(ac97, reg, shadow_reg, 76100 / 2))
			result &= ~SNDRV_PCM_RATE_CONTINUOUS;
		snd_ac97_update_bits(ac97, AC97_EXTENDED_STATUS,
				     AC97_EA_DRA, 0);
	}
	*r_result = result;
}

/* check AC97_SPDIF register to accept which sample rates */
static unsigned int snd_ac97_determine_spdif_rates(ac97_t *ac97)
{
	unsigned int result = 0;
	int i;
	static unsigned short ctl_bits[] = {
		AC97_SC_SPSR_44K, AC97_SC_SPSR_32K, AC97_SC_SPSR_48K
	};
	static unsigned int rate_bits[] = {
		SNDRV_PCM_RATE_44100, SNDRV_PCM_RATE_32000, SNDRV_PCM_RATE_48000
	};

	for (i = 0; i < (int)ARRAY_SIZE(ctl_bits); i++) {
		snd_ac97_update_bits(ac97, AC97_SPDIF, AC97_SC_SPSR_MASK, ctl_bits[i]);
		if ((snd_ac97_read(ac97, AC97_SPDIF) & AC97_SC_SPSR_MASK) == ctl_bits[i])
			result |= rate_bits[i];
	}
	return result;
}

void snd_ac97_get_name(ac97_t *ac97, unsigned int id, char *name, int modem)
{
	const ac97_codec_id_t *pid;

	sprintf(name, "0x%x %c%c%c", id,
		printable(id >> 24),
		printable(id >> 16),
		printable(id >> 8));
	for (pid = snd_ac97_codec_id_vendors; pid->id; pid++)
		if (pid->id == (id & pid->mask)) {
			strcpy(name, pid->name);
			if (ac97) {
				if (!modem && pid->patch)
					pid->patch(ac97);
				else if (modem && pid->mpatch)
					pid->mpatch(ac97);
			} 
			goto __vendor_ok;
		}
	return;

      __vendor_ok:
	for (pid = snd_ac97_codec_ids; pid->id; pid++)
		if (pid->id == (id & pid->mask)) {
			strcat(name, " ");
			strcat(name, pid->name);
			if (pid->mask != 0xffffffff)
				sprintf(name + strlen(name), " rev %d", id & ~pid->mask);
			if (ac97) {
				if (!modem && pid->patch)
					pid->patch(ac97);
				else if (modem && pid->mpatch)
					pid->mpatch(ac97);
			}
			return;
		}
	sprintf(name + strlen(name), " id %x", id & 0xff);
}

/**
 * snd_ac97_get_short_name - retrieve codec name
 * @ac97: the codec instance
 *
 * Returns the short identifying name of the codec.
 */
const char *snd_ac97_get_short_name(ac97_t *ac97)
{
	const ac97_codec_id_t *pid;

	for (pid = snd_ac97_codec_ids; pid->id; pid++)
		if (pid->id == (ac97->id & pid->mask))
			return pid->name;
	return "unknown codec";
}


/* wait for a while until registers are accessible after RESET
 * return 0 if ok, negative not ready
 */
static int ac97_reset_wait(ac97_t *ac97, int timeout, int with_modem)
{
	unsigned long end_time;
	unsigned short val;

	end_time = jiffies + timeout;
	do {
		
		/* use preliminary reads to settle the communication */
		snd_ac97_read(ac97, AC97_RESET);
		snd_ac97_read(ac97, AC97_VENDOR_ID1);
		snd_ac97_read(ac97, AC97_VENDOR_ID2);
		/* modem? */
		if (with_modem) {
			val = snd_ac97_read(ac97, AC97_EXTENDED_MID);
			if (val != 0xffff && (val & 1) != 0)
				return 0;
		}
		if (ac97->scaps & AC97_SCAP_DETECT_BY_VENDOR) {
			/* probably only Xbox issue - all registers are read as zero */
			val = snd_ac97_read(ac97, AC97_VENDOR_ID1);
			if (val != 0 && val != 0xffff)
				return 0;
		} else {
			/* because the PCM or MASTER volume registers can be modified,
			 * the REC_GAIN register is used for tests
			 */
			/* test if we can write to the record gain volume register */
			snd_ac97_write_cache(ac97, AC97_REC_GAIN, 0x8a05);
			if ((snd_ac97_read(ac97, AC97_REC_GAIN) & 0x7fff) == 0x0a05)
				return 0;
		}
		set_current_state(TASK_UNINTERRUPTIBLE);
		schedule_timeout(1);
	} while (time_after_eq(end_time, jiffies));
	return -ENODEV;
}

/**
 * snd_ac97_bus - create an AC97 bus component
 * @card: the card instance
 * @num: the bus number
 * @ops: the bus callbacks table
 * @private_data: private data pointer for the new instance
 * @rbus: the pointer to store the new AC97 bus instance.
 *
 * Creates an AC97 bus component.  An ac97_bus_t instance is newly
 * allocated and initialized.
 *
 * The ops table must include valid callbacks (at least read and
 * write).  The other callbacks, wait and reset, are not mandatory.
 * 
 * The clock is set to 48000.  If another clock is needed, set
 * (*rbus)->clock manually.
 *
 * The AC97 bus instance is registered as a low-level device, so you don't
 * have to release it manually.
 *
 * Returns zero if successful, or a negative error code on failure.
 */
int snd_ac97_bus(snd_card_t *card, int num, ac97_bus_ops_t *ops,
		 void *private_data, ac97_bus_t **rbus)
{
	int err;
	ac97_bus_t *bus;
	static snd_device_ops_t dev_ops = {
		.dev_free =	snd_ac97_bus_dev_free,
	};

	snd_assert(card != NULL, return -EINVAL);
	snd_assert(rbus != NULL, return -EINVAL);
	bus = kcalloc(1, sizeof(*bus), GFP_KERNEL);
	if (bus == NULL)
		return -ENOMEM;
	bus->card = card;
	bus->num = num;
	bus->ops = ops;
	bus->private_data = private_data;
	bus->clock = 48000;
	spin_lock_init(&bus->bus_lock);
	snd_ac97_bus_proc_init(bus);
	if ((err = snd_device_new(card, SNDRV_DEV_BUS, bus, &dev_ops)) < 0) {
		snd_ac97_bus_free(bus);
		return err;
	}
	*rbus = bus;
	return 0;
}

/* build_ops to do nothing */
static struct snd_ac97_build_ops null_build_ops;

/**
 * snd_ac97_mixer - create an Codec97 component
 * @bus: the AC97 bus which codec is attached to
 * @template: the template of ac97, including index, callbacks and
 *         the private data.
 * @rac97: the pointer to store the new ac97 instance.
 *
 * Creates an Codec97 component.  An ac97_t instance is newly
 * allocated and initialized from the template.  The codec
 * is then initialized by the standard procedure.
 *
 * The template must include the codec number (num) and address (addr),
 * and the private data (private_data).
 * 
 * The ac97 instance is registered as a low-level device, so you don't
 * have to release it manually.
 *
 * Returns zero if successful, or a negative error code on failure.
 */
int snd_ac97_mixer(ac97_bus_t *bus, ac97_template_t *template, ac97_t **rac97)
{
	int err;
	ac97_t *ac97;
	snd_card_t *card;
	char name[64];
	unsigned long end_time;
	unsigned int reg;
	static snd_device_ops_t ops = {
		.dev_free =	snd_ac97_dev_free,
	};

	snd_assert(rac97 != NULL, return -EINVAL);
	*rac97 = NULL;
	snd_assert(bus != NULL && template != NULL, return -EINVAL);
	snd_assert(template->num < 4 && bus->codec[template->num] == NULL, return -EINVAL);

	snd_assert(bus->shared_type <= AC97_SHARED_TYPES, return -EINVAL);
	if (bus->shared_type) {
		/* already shared? */
		down(&shared_codec_mutex);
		ac97 = shared_codec[bus->shared_type-1][template->num];
		if (ac97) {
			if ((ac97_is_audio(ac97) && (template->scaps & AC97_SCAP_SKIP_AUDIO)) ||
			    (ac97_is_modem(ac97) && (template->scaps & AC97_SCAP_SKIP_MODEM))) {
				up(&shared_codec_mutex);
				return -EACCES; /* skip this */
			}
		}
		up(&shared_codec_mutex);
	}

	card = bus->card;
	ac97 = kcalloc(1, sizeof(*ac97), GFP_KERNEL);
	if (ac97 == NULL)
		return -ENOMEM;
	ac97->private_data = template->private_data;
	ac97->private_free = template->private_free;
	ac97->bus = bus;
	ac97->pci = template->pci;
	ac97->num = template->num;
	ac97->addr = template->addr;
	ac97->scaps = template->scaps;
	ac97->limited_regs = template->limited_regs;
	memcpy(ac97->reg_accessed, template->reg_accessed, sizeof(ac97->reg_accessed));
	bus->codec[ac97->num] = ac97;
	init_MUTEX(&ac97->reg_mutex);
	init_MUTEX(&ac97->page_mutex);

	if (ac97->pci) {
		pci_read_config_word(ac97->pci, PCI_SUBSYSTEM_VENDOR_ID, &ac97->subsystem_vendor);
		pci_read_config_word(ac97->pci, PCI_SUBSYSTEM_ID, &ac97->subsystem_device);
	}
	if (bus->ops->reset) {
		bus->ops->reset(ac97);
		goto __access_ok;
	}

	snd_ac97_write(ac97, AC97_RESET, 0);	/* reset to defaults */
	if (bus->ops->wait)
		bus->ops->wait(ac97);
	else {
		udelay(50);
		if (ac97->scaps & AC97_SCAP_SKIP_AUDIO)
			err = ac97_reset_wait(ac97, HZ/2, 1);
		else {
			err = ac97_reset_wait(ac97, HZ/2, 0);
			if (err < 0)
				err = ac97_reset_wait(ac97, HZ/2, 1);
		}
		if (err < 0) {
			snd_printk(KERN_WARNING "AC'97 %d does not respond - RESET\n", ac97->num);
			/* proceed anyway - it's often non-critical */
		}
	}
      __access_ok:
	ac97->id = snd_ac97_read(ac97, AC97_VENDOR_ID1) << 16;
	ac97->id |= snd_ac97_read(ac97, AC97_VENDOR_ID2);
	if (! (ac97->scaps & AC97_SCAP_DETECT_BY_VENDOR) &&
	    (ac97->id == 0x00000000 || ac97->id == 0xffffffff)) {
		snd_printk(KERN_ERR "AC'97 %d access is not valid [0x%x], removing mixer.\n", ac97->num, ac97->id);
		snd_ac97_free(ac97);
		return -EIO;
	}
	
	/* test for AC'97 */
	if (!(ac97->scaps & AC97_SCAP_SKIP_AUDIO) && !(ac97->scaps & AC97_SCAP_AUDIO)) {
		/* test if we can write to the record gain volume register */
		snd_ac97_write_cache(ac97, AC97_REC_GAIN, 0x8a06);
		if (((err = snd_ac97_read(ac97, AC97_REC_GAIN)) & 0x7fff) == 0x0a06)
			ac97->scaps |= AC97_SCAP_AUDIO;
	}
	if (ac97->scaps & AC97_SCAP_AUDIO) {
		ac97->caps = snd_ac97_read(ac97, AC97_RESET);
		ac97->ext_id = snd_ac97_read(ac97, AC97_EXTENDED_ID);
		if (ac97->ext_id == 0xffff)	/* invalid combination */
			ac97->ext_id = 0;
	}

	/* test for MC'97 */
	if (!(ac97->scaps & AC97_SCAP_SKIP_MODEM) && !(ac97->scaps & AC97_SCAP_MODEM)) {
		ac97->ext_mid = snd_ac97_read(ac97, AC97_EXTENDED_MID);
		if (ac97->ext_mid == 0xffff)	/* invalid combination */
			ac97->ext_mid = 0;
		if (ac97->ext_mid & 1)
			ac97->scaps |= AC97_SCAP_MODEM;
	}

	if (!ac97_is_audio(ac97) && !ac97_is_modem(ac97)) {
		if (!(ac97->scaps & (AC97_SCAP_SKIP_AUDIO|AC97_SCAP_SKIP_MODEM)))
			snd_printk(KERN_ERR "AC'97 %d access error (not audio or modem codec)\n", ac97->num);
		snd_ac97_free(ac97);
		return -EACCES;
	}

	if (bus->ops->reset) // FIXME: always skipping?
		goto __ready_ok;

	/* FIXME: add powerdown control */
	if (ac97_is_audio(ac97)) {
		/* nothing should be in powerdown mode */
		snd_ac97_write_cache(ac97, AC97_POWERDOWN, 0);
		snd_ac97_write_cache(ac97, AC97_RESET, 0);		/* reset to defaults */
		udelay(100);
		/* nothing should be in powerdown mode */
		snd_ac97_write_cache(ac97, AC97