es1968.c

linux 内核源代码

	/* playback/capture pcm buffer */
	struct esm_memory *memory;
	/* capture mixer buffer */
	struct esm_memory *mixbuf;

	unsigned int hwptr;	/* current hw pointer in bytes */
	unsigned int count;	/* sample counter in bytes */
	unsigned int dma_size;	/* total buffer size in bytes */
	unsigned int frag_size;	/* period size in bytes */
	unsigned int wav_shift;
	u16 base[4];		/* offset for ptr */

	/* stereo/16bit flag */
	unsigned char fmt;
	int mode;	/* playback / capture */

	int bob_freq;	/* required timer frequency */

	struct snd_pcm_substream *substream;

	/* linked list */
	struct list_head list;

#ifdef CONFIG_PM
	u16 wc_map[4];
#endif
};

struct es1968 {
	/* Module Config */
	int total_bufsize;			/* in bytes */

	int playback_streams, capture_streams;

	unsigned int clock;		/* clock */
	/* for clock measurement */
	unsigned int in_measurement: 1;
	unsigned int measure_apu;
	unsigned int measure_lastpos;
	unsigned int measure_count;

	/* buffer */
	struct snd_dma_buffer dma;

	/* Resources... */
	int irq;
	unsigned long io_port;
	int type;
	struct pci_dev *pci;
	struct snd_card *card;
	struct snd_pcm *pcm;
	int do_pm;		/* power-management enabled */

	/* DMA memory block */
	struct list_head buf_list;

	/* ALSA Stuff */
	struct snd_ac97 *ac97;
	struct snd_kcontrol *master_switch; /* for h/w volume control */
	struct snd_kcontrol *master_volume;

	struct snd_rawmidi *rmidi;

	spinlock_t reg_lock;
	spinlock_t ac97_lock;
	struct tasklet_struct hwvol_tq;
	unsigned int in_suspend;

	/* Maestro Stuff */
	u16 maestro_map[32];
	int bobclient;		/* active timer instancs */
	int bob_freq;		/* timer frequency */
	struct mutex memory_mutex;	/* memory lock */

	/* APU states */
	unsigned char apu[NR_APUS];

	/* active substreams */
	struct list_head substream_list;
	spinlock_t substream_lock;

#ifdef CONFIG_PM
	u16 apu_map[NR_APUS][NR_APU_REGS];
#endif

#ifdef SUPPORT_JOYSTICK
	struct gameport *gameport;
#endif
};

static irqreturn_t snd_es1968_interrupt(int irq, void *dev_id);

static struct pci_device_id snd_es1968_ids[] = {
	/* Maestro 1 */
        { 0x1285, 0x0100, PCI_ANY_ID, PCI_ANY_ID, PCI_CLASS_MULTIMEDIA_AUDIO << 8, 0xffff00, TYPE_MAESTRO },
	/* Maestro 2 */
	{ 0x125d, 0x1968, PCI_ANY_ID, PCI_ANY_ID, PCI_CLASS_MULTIMEDIA_AUDIO << 8, 0xffff00, TYPE_MAESTRO2 },
	/* Maestro 2E */
        { 0x125d, 0x1978, PCI_ANY_ID, PCI_ANY_ID, PCI_CLASS_MULTIMEDIA_AUDIO << 8, 0xffff00, TYPE_MAESTRO2E },
	{ 0, }
};

MODULE_DEVICE_TABLE(pci, snd_es1968_ids);

/* *********************
   * Low Level Funcs!  *
   *********************/

/* no spinlock */
static void __maestro_write(struct es1968 *chip, u16 reg, u16 data)
{
	outw(reg, chip->io_port + ESM_INDEX);
	outw(data, chip->io_port + ESM_DATA);
	chip->maestro_map[reg] = data;
}

static inline void maestro_write(struct es1968 *chip, u16 reg, u16 data)
{
	unsigned long flags;
	spin_lock_irqsave(&chip->reg_lock, flags);
	__maestro_write(chip, reg, data);
	spin_unlock_irqrestore(&chip->reg_lock, flags);
}

/* no spinlock */
static u16 __maestro_read(struct es1968 *chip, u16 reg)
{
	if (READABLE_MAP & (1 << reg)) {
		outw(reg, chip->io_port + ESM_INDEX);
		chip->maestro_map[reg] = inw(chip->io_port + ESM_DATA);
	}
	return chip->maestro_map[reg];
}

static inline u16 maestro_read(struct es1968 *chip, u16 reg)
{
	unsigned long flags;
	u16 result;
	spin_lock_irqsave(&chip->reg_lock, flags);
	result = __maestro_read(chip, reg);
	spin_unlock_irqrestore(&chip->reg_lock, flags);
	return result;
}

/* Wait for the codec bus to be free */
static int snd_es1968_ac97_wait(struct es1968 *chip)
{
	int timeout = 100000;

	while (timeout-- > 0) {
		if (!(inb(chip->io_port + ESM_AC97_INDEX) & 1))
			return 0;
		cond_resched();
	}
	snd_printd("es1968: ac97 timeout\n");
	return 1; /* timeout */
}

static void snd_es1968_ac97_write(struct snd_ac97 *ac97, unsigned short reg, unsigned short val)
{
	struct es1968 *chip = ac97->private_data;
	unsigned long flags;

	snd_es1968_ac97_wait(chip);

	/* Write the bus */
	spin_lock_irqsave(&chip->ac97_lock, flags);
	outw(val, chip->io_port + ESM_AC97_DATA);
	/*msleep(1);*/
	outb(reg, chip->io_port + ESM_AC97_INDEX);
	/*msleep(1);*/
	spin_unlock_irqrestore(&chip->ac97_lock, flags);
}

static unsigned short snd_es1968_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
{
	u16 data = 0;
	struct es1968 *chip = ac97->private_data;
	unsigned long flags;

	snd_es1968_ac97_wait(chip);

	spin_lock_irqsave(&chip->ac97_lock, flags);
	outb(reg | 0x80, chip->io_port + ESM_AC97_INDEX);
	/*msleep(1);*/

	if (! snd_es1968_ac97_wait(chip)) {
		data = inw(chip->io_port + ESM_AC97_DATA);
		/*msleep(1);*/
	}
	spin_unlock_irqrestore(&chip->ac97_lock, flags);

	return data;
}

/* no spinlock */
static void apu_index_set(struct es1968 *chip, u16 index)
{
	int i;
	__maestro_write(chip, IDR1_CRAM_POINTER, index);
	for (i = 0; i < 1000; i++)
		if (__maestro_read(chip, IDR1_CRAM_POINTER) == index)
			return;
	snd_printd("es1968: APU register select failed. (Timeout)\n");
}

/* no spinlock */
static void apu_data_set(struct es1968 *chip, u16 data)
{
	int i;
	for (i = 0; i < 1000; i++) {
		if (__maestro_read(chip, IDR0_DATA_PORT) == data)
			return;
		__maestro_write(chip, IDR0_DATA_PORT, data);
	}
	snd_printd("es1968: APU register set probably failed (Timeout)!\n");
}

/* no spinlock */
static void __apu_set_register(struct es1968 *chip, u16 channel, u8 reg, u16 data)
{
	snd_assert(channel < NR_APUS, return);
#ifdef CONFIG_PM
	chip->apu_map[channel][reg] = data;
#endif
	reg |= (channel << 4);
	apu_index_set(chip, reg);
	apu_data_set(chip, data);
}

static void apu_set_register(struct es1968 *chip, u16 channel, u8 reg, u16 data)
{
	unsigned long flags;
	spin_lock_irqsave(&chip->reg_lock, flags);
	__apu_set_register(chip, channel, reg, data);
	spin_unlock_irqrestore(&chip->reg_lock, flags);
}

static u16 __apu_get_register(struct es1968 *chip, u16 channel, u8 reg)
{
	snd_assert(channel < NR_APUS, return 0);
	reg |= (channel << 4);
	apu_index_set(chip, reg);
	return __maestro_read(chip, IDR0_DATA_PORT);
}

static u16 apu_get_register(struct es1968 *chip, u16 channel, u8 reg)
{
	unsigned long flags;
	u16 v;
	spin_lock_irqsave(&chip->reg_lock, flags);
	v = __apu_get_register(chip, channel, reg);
	spin_unlock_irqrestore(&chip->reg_lock, flags);
	return v;
}

#if 0 /* ASSP is not supported */

static void assp_set_register(struct es1968 *chip, u32 reg, u32 value)
{
	unsigned long flags;

	spin_lock_irqsave(&chip->reg_lock, flags);
	outl(reg, chip->io_port + ASSP_INDEX);
	outl(value, chip->io_port + ASSP_DATA);
	spin_unlock_irqrestore(&chip->reg_lock, flags);
}

static u32 assp_get_register(struct es1968 *chip, u32 reg)
{
	unsigned long flags;
	u32 value;

	spin_lock_irqsave(&chip->reg_lock, flags);
	outl(reg, chip->io_port + ASSP_INDEX);
	value = inl(chip->io_port + ASSP_DATA);
	spin_unlock_irqrestore(&chip->reg_lock, flags);

	return value;
}

#endif

static void wave_set_register(struct es1968 *chip, u16 reg, u16 value)
{
	unsigned long flags;

	spin_lock_irqsave(&chip->reg_lock, flags);
	outw(reg, chip->io_port + WC_INDEX);
	outw(value, chip->io_port + WC_DATA);
	spin_unlock_irqrestore(&chip->reg_lock, flags);
}

static u16 wave_get_register(struct es1968 *chip, u16 reg)
{
	unsigned long flags;
	u16 value;

	spin_lock_irqsave(&chip->reg_lock, flags);
	outw(reg, chip->io_port + WC_INDEX);
	value = inw(chip->io_port + WC_DATA);
	spin_unlock_irqrestore(&chip->reg_lock, flags);

	return value;
}

/* *******************
   * Bob the Timer!  *
   *******************/

static void snd_es1968_bob_stop(struct es1968 *chip)
{
	u16 reg;

	reg = __maestro_read(chip, 0x11);
	reg &= ~ESM_BOB_ENABLE;
	__maestro_write(chip, 0x11, reg);
	reg = __maestro_read(chip, 0x17);
	reg &= ~ESM_BOB_START;
	__maestro_write(chip, 0x17, reg);
}

static void snd_es1968_bob_start(struct es1968 *chip)
{
	int prescale;
	int divide;

	/* compute ideal interrupt frequency for buffer size & play rate */
	/* first, find best prescaler value to match freq */
	for (prescale = 5; prescale < 12; prescale++)
		if (chip->bob_freq > (ESS_SYSCLK >> (prescale + 9)))
			break;

	/* next, back off prescaler whilst getting divider into optimum range */
	divide = 1;
	while ((prescale > 5) && (divide < 32)) {
		prescale--;
		divide <<= 1;
	}
	divide >>= 1;

	/* now fine-tune the divider for best match */
	for (; divide < 31; divide++)
		if (chip->bob_freq >
		    ((ESS_SYSCLK >> (prescale + 9)) / (divide + 1))) break;

	/* divide = 0 is illegal, but don't let prescale = 4! */
	if (divide == 0) {
		divide++;
		if (prescale > 5)
			prescale--;
	} else if (divide > 1)
		divide--;

	__maestro_write(chip, 6, 0x9000 | (prescale << 5) | divide);	/* set reg */

	/* Now set IDR 11/17 */
	__maestro_write(chip, 0x11, __maestro_read(chip, 0x11) | 1);
	__maestro_write(chip, 0x17, __maestro_read(chip, 0x17) | 1);
}

/* call with substream spinlock */
static void snd_es1968_bob_inc(struct es1968 *chip, int freq)
{
	chip->bobclient++;
	if (chip->bobclient == 1) {
		chip->bob_freq = freq;
		snd_es1968_bob_start(chip);
	} else if (chip->bob_freq < freq) {
		snd_es1968_bob_stop(chip);
		chip->bob_freq = freq;
		snd_es1968_bob_start(chip);
	}
}

/* call with substream spinlock */
static void snd_es1968_bob_dec(struct es1968 *chip)
{
	chip->bobclient--;
	if (chip->bobclient <= 0)
		snd_es1968_bob_stop(chip);
	else if (chip->bob_freq > ESM_BOB_FREQ) {
		/* check reduction of timer frequency */
		int max_freq = ESM_BOB_FREQ;
		struct esschan *es;
		list_for_each_entry(es, &chip->substream_list, list) {
			if (max_freq < es->bob_freq)
				max_freq = es->bob_freq;
		}
		if (max_freq != chip->bob_freq) {
			snd_es1968_bob_stop(chip);
			chip->bob_freq = max_freq;
			snd_es1968_bob_start(chip);
		}
	}
}

static int
snd_es1968_calc_bob_rate(struct es1968 *chip, struct esschan *es,
			 struct snd_pcm_runtime *runtime)
{
	/* we acquire 4 interrupts per period for precise control.. */
	int freq = runtime->rate * 4;
	if (es->fmt & ESS_FMT_STEREO)
		freq <<= 1;
	if (es->fmt & ESS_FMT_16BIT)
		freq <<= 1;
	freq /= es->frag_size;
	if (freq < ESM_BOB_FREQ)
		freq = ESM_BOB_FREQ;
	else if (freq > ESM_BOB_FREQ_MAX)
		freq = ESM_BOB_FREQ_MAX;
	return freq;
}


/*************
 *  PCM Part *
 *************/

static u32 snd_es1968_compute_rate(struct es1968 *chip, u32 freq)
{
	u32 rate = (freq << 16) / chip->clock;
#if 0 /* XXX: do we need this? */ 
	if (rate > 0x10000)
		rate = 0x10000;
#endif
	return rate;
}

/* get current pointer */
static inline unsigned int
snd_es1968_get_dma_ptr(struct es1968 *chip, struct esschan *es)
{
	unsigned int offset;

	offset = apu_get_register(chip, es->apu[0], 5);

	offset -= es->base[0];

	return (offset & 0xFFFE);	/* hardware is in words */
}

static void snd_es1968_apu_set_freq(struct es1968 *chip, int apu, int freq)
{
	apu_set_register(chip, apu, 2,
			   (apu_get_register(chip, apu, 2) & 0x00FF) |
			   ((freq & 0xff) << 8) | 0x10);
	apu_set_register(chip, apu, 3, freq >> 8);
}

/* spin lock held */
static inline void snd_es1968_trigger_apu(struct es1968 *esm, int apu, int mode)
{
	/* set the APU mode */
	__apu_set_register(esm, apu, 0,
			   (__apu_get_register(esm, apu, 0) & 0xff0f) |
			   (mode << 4));
}

static void snd_es1968_pcm_start(struct es1968 *chip, struct esschan *es)
{