hdsp.c

linux 内核源代码

	int ret = 1;

	spin_lock_irqsave(&hdsp->lock, flags);
	if ((hdsp->playback_pid != hdsp->capture_pid) &&
	    (hdsp->playback_pid >= 0) && (hdsp->capture_pid >= 0))
		ret = 0;
	spin_unlock_irqrestore(&hdsp->lock, flags);
	return ret;
}

static int hdsp_external_sample_rate (struct hdsp *hdsp)
{
	unsigned int status2 = hdsp_read(hdsp, HDSP_status2Register);
	unsigned int rate_bits = status2 & HDSP_systemFrequencyMask;

	switch (rate_bits) {
	case HDSP_systemFrequency32:   return 32000;
	case HDSP_systemFrequency44_1: return 44100;
	case HDSP_systemFrequency48:   return 48000;
	case HDSP_systemFrequency64:   return 64000;
	case HDSP_systemFrequency88_2: return 88200;
	case HDSP_systemFrequency96:   return 96000;
	default:
		return 0;
	}
}

static int hdsp_spdif_sample_rate(struct hdsp *hdsp)
{
	unsigned int status = hdsp_read(hdsp, HDSP_statusRegister);
	unsigned int rate_bits = (status & HDSP_spdifFrequencyMask);

	if (status & HDSP_SPDIFErrorFlag)
		return 0;
	
	switch (rate_bits) {
	case HDSP_spdifFrequency32KHz: return 32000;
	case HDSP_spdifFrequency44_1KHz: return 44100;
	case HDSP_spdifFrequency48KHz: return 48000;
	case HDSP_spdifFrequency64KHz: return 64000;
	case HDSP_spdifFrequency88_2KHz: return 88200;
	case HDSP_spdifFrequency96KHz: return 96000;
	case HDSP_spdifFrequency128KHz: 
		if (hdsp->io_type == H9632) return 128000;
		break;
	case HDSP_spdifFrequency176_4KHz: 
		if (hdsp->io_type == H9632) return 176400;
		break;
	case HDSP_spdifFrequency192KHz: 
		if (hdsp->io_type == H9632) return 192000;
		break;
	default:
		break;
	}
	snd_printk ("Hammerfall-DSP: unknown spdif frequency status; bits = 0x%x, status = 0x%x\n", rate_bits, status);
	return 0;
}

static void hdsp_compute_period_size(struct hdsp *hdsp)
{
	hdsp->period_bytes = 1 << ((hdsp_decode_latency(hdsp->control_register) + 8));
}

static snd_pcm_uframes_t hdsp_hw_pointer(struct hdsp *hdsp)
{
	int position;

	position = hdsp_read(hdsp, HDSP_statusRegister);

	if (!hdsp->precise_ptr)
		return (position & HDSP_BufferID) ? (hdsp->period_bytes / 4) : 0;

	position &= HDSP_BufferPositionMask;
	position /= 4;
	position &= (hdsp->period_bytes/2) - 1;
	return position;
}

static void hdsp_reset_hw_pointer(struct hdsp *hdsp)
{
	hdsp_write (hdsp, HDSP_resetPointer, 0);
	if (hdsp->io_type == H9632 && hdsp->firmware_rev >= 152)
		/* HDSP_resetPointer = HDSP_freqReg, which is strange and
		 * requires (?) to write again DDS value after a reset pointer
		 * (at least, it works like this) */
		hdsp_write (hdsp, HDSP_freqReg, hdsp->dds_value);
}

static void hdsp_start_audio(struct hdsp *s)
{
	s->control_register |= (HDSP_AudioInterruptEnable | HDSP_Start);
	hdsp_write(s, HDSP_controlRegister, s->control_register);
}

static void hdsp_stop_audio(struct hdsp *s)
{
	s->control_register &= ~(HDSP_Start | HDSP_AudioInterruptEnable);
	hdsp_write(s, HDSP_controlRegister, s->control_register);
}

static void hdsp_silence_playback(struct hdsp *hdsp)
{
	memset(hdsp->playback_buffer, 0, HDSP_DMA_AREA_BYTES);
}

static int hdsp_set_interrupt_interval(struct hdsp *s, unsigned int frames)
{
	int n;

	spin_lock_irq(&s->lock);

	frames >>= 7;
	n = 0;
	while (frames) {
		n++;
		frames >>= 1;
	}

	s->control_register &= ~HDSP_LatencyMask;
	s->control_register |= hdsp_encode_latency(n);

	hdsp_write(s, HDSP_controlRegister, s->control_register);

	hdsp_compute_period_size(s);

	spin_unlock_irq(&s->lock);

	return 0;
}

static void hdsp_set_dds_value(struct hdsp *hdsp, int rate)
{
	u64 n;
	u32 r;
	
	if (rate >= 112000)
		rate /= 4;
	else if (rate >= 56000)
		rate /= 2;

	n = DDS_NUMERATOR;
	div64_32(&n, rate, &r);
	/* n should be less than 2^32 for being written to FREQ register */
	snd_assert((n >> 32) == 0);
	/* HDSP_freqReg and HDSP_resetPointer are the same, so keep the DDS
	   value to write it after a reset */
	hdsp->dds_value = n;
	hdsp_write(hdsp, HDSP_freqReg, hdsp->dds_value);
}

static int hdsp_set_rate(struct hdsp *hdsp, int rate, int called_internally)
{
	int reject_if_open = 0;
	int current_rate;
	int rate_bits;

	/* ASSUMPTION: hdsp->lock is either held, or
	   there is no need for it (e.g. during module
	   initialization).
	*/
	
	if (!(hdsp->control_register & HDSP_ClockModeMaster)) {	
		if (called_internally) {
			/* request from ctl or card initialization */
			snd_printk(KERN_ERR "Hammerfall-DSP: device is not running as a clock master: cannot set sample rate.\n");
			return -1;
		} else {		
			/* hw_param request while in AutoSync mode */
			int external_freq = hdsp_external_sample_rate(hdsp);
			int spdif_freq = hdsp_spdif_sample_rate(hdsp);
		
			if ((spdif_freq == external_freq*2) && (hdsp_autosync_ref(hdsp) >= HDSP_AUTOSYNC_FROM_ADAT1))
				snd_printk(KERN_INFO "Hammerfall-DSP: Detected ADAT in double speed mode\n");
			else if (hdsp->io_type == H9632 && (spdif_freq == external_freq*4) && (hdsp_autosync_ref(hdsp) >= HDSP_AUTOSYNC_FROM_ADAT1))
				snd_printk(KERN_INFO "Hammerfall-DSP: Detected ADAT in quad speed mode\n");			
			else if (rate != external_freq) {
				snd_printk(KERN_INFO "Hammerfall-DSP: No AutoSync source for requested rate\n");
				return -1;
			}		
		}	
	}

	current_rate = hdsp->system_sample_rate;

	/* Changing from a "single speed" to a "double speed" rate is
	   not allowed if any substreams are open. This is because
	   such a change causes a shift in the location of 
	   the DMA buffers and a reduction in the number of available
	   buffers. 

	   Note that a similar but essentially insoluble problem
	   exists for externally-driven rate changes. All we can do
	   is to flag rate changes in the read/write routines.  */

	if (rate > 96000 && hdsp->io_type != H9632)
		return -EINVAL;
	
	switch (rate) {
	case 32000:
		if (current_rate > 48000)
			reject_if_open = 1;
		rate_bits = HDSP_Frequency32KHz;
		break;
	case 44100:
		if (current_rate > 48000)
			reject_if_open = 1;
		rate_bits = HDSP_Frequency44_1KHz;
		break;
	case 48000:
		if (current_rate > 48000)
			reject_if_open = 1;
		rate_bits = HDSP_Frequency48KHz;
		break;
	case 64000:
		if (current_rate <= 48000 || current_rate > 96000)
			reject_if_open = 1;
		rate_bits = HDSP_Frequency64KHz;
		break;
	case 88200:
		if (current_rate <= 48000 || current_rate > 96000)
			reject_if_open = 1;
		rate_bits = HDSP_Frequency88_2KHz;
		break;
	case 96000:
		if (current_rate <= 48000 || current_rate > 96000)
			reject_if_open = 1;
		rate_bits = HDSP_Frequency96KHz;
		break;
	case 128000:
		if (current_rate < 128000)
			reject_if_open = 1;
		rate_bits = HDSP_Frequency128KHz;
		break;
	case 176400:
		if (current_rate < 128000)
			reject_if_open = 1;
		rate_bits = HDSP_Frequency176_4KHz;
		break;
	case 192000:
		if (current_rate < 128000)
			reject_if_open = 1;
		rate_bits = HDSP_Frequency192KHz;
		break;
	default:
		return -EINVAL;
	}

	if (reject_if_open && (hdsp->capture_pid >= 0 || hdsp->playback_pid >= 0)) {
		snd_printk ("Hammerfall-DSP: cannot change speed mode (capture PID = %d, playback PID = %d)\n",
			    hdsp->capture_pid,
			    hdsp->playback_pid);
		return -EBUSY;
	}

	hdsp->control_register &= ~HDSP_FrequencyMask;
	hdsp->control_register |= rate_bits;
	hdsp_write(hdsp, HDSP_controlRegister, hdsp->control_register);

	/* For HDSP9632 rev 152, need to set DDS value in FREQ register */
	if (hdsp->io_type == H9632 && hdsp->firmware_rev >= 152)
		hdsp_set_dds_value(hdsp, rate);

	if (rate >= 128000) {
		hdsp->channel_map = channel_map_H9632_qs;
	} else if (rate > 48000) {
		if (hdsp->io_type == H9632)
			hdsp->channel_map = channel_map_H9632_ds;
		else
			hdsp->channel_map = channel_map_ds;
	} else {
		switch (hdsp->io_type) {
		case Multiface:
			hdsp->channel_map = channel_map_mf_ss;
			break;
		case Digiface:
		case H9652:
			hdsp->channel_map = channel_map_df_ss;
			break;
		case H9632:
			hdsp->channel_map = channel_map_H9632_ss;
			break;
		default:
			/* should never happen */
			break;
		}
	}
	
	hdsp->system_sample_rate = rate;

	return 0;
}

/*----------------------------------------------------------------------------
   MIDI
  ----------------------------------------------------------------------------*/

static unsigned char snd_hdsp_midi_read_byte (struct hdsp *hdsp, int id)
{
	/* the hardware already does the relevant bit-mask with 0xff */
	if (id)
		return hdsp_read(hdsp, HDSP_midiDataIn1);
	else
		return hdsp_read(hdsp, HDSP_midiDataIn0);
}

static void snd_hdsp_midi_write_byte (struct hdsp *hdsp, int id, int val)
{
	/* the hardware already does the relevant bit-mask with 0xff */
	if (id)
		hdsp_write(hdsp, HDSP_midiDataOut1, val);
	else
		hdsp_write(hdsp, HDSP_midiDataOut0, val);
}

static int snd_hdsp_midi_input_available (struct hdsp *hdsp, int id)
{
	if (id)
		return (hdsp_read(hdsp, HDSP_midiStatusIn1) & 0xff);
	else
		return (hdsp_read(hdsp, HDSP_midiStatusIn0) & 0xff);
}

static int snd_hdsp_midi_output_possible (struct hdsp *hdsp, int id)
{
	int fifo_bytes_used;

	if (id)
		fifo_bytes_used = hdsp_read(hdsp, HDSP_midiStatusOut1) & 0xff;
	else
		fifo_bytes_used = hdsp_read(hdsp, HDSP_midiStatusOut0) & 0xff;

	if (fifo_bytes_used < 128)
		return  128 - fifo_bytes_used;
	else
		return 0;
}

static void snd_hdsp_flush_midi_input (struct hdsp *hdsp, int id)
{
	while (snd_hdsp_midi_input_available (hdsp, id))
		snd_hdsp_midi_read_byte (hdsp, id);
}

static int snd_hdsp_midi_output_write (struct hdsp_midi *hmidi)
{
	unsigned long flags;
	int n_pending;
	int to_write;
	int i;
	unsigned char buf[128];

	/* Output is not interrupt driven */
		
	spin_lock_irqsave (&hmidi->lock, flags);
	if (hmidi->output) {
		if (!snd_rawmidi_transmit_empty (hmidi->output)) {
			if ((n_pending = snd_hdsp_midi_output_possible (hmidi->hdsp, hmidi->id)) > 0) {
				if (n_pending > (int)sizeof (buf))
					n_pending = sizeof (buf);
				
				if ((to_write = snd_rawmidi_transmit (hmidi->output, buf, n_pending)) > 0) {
					for (i = 0; i < to_write; ++i) 
						snd_hdsp_midi_write_byte (hmidi->hdsp, hmidi->id, buf[i]);
				}
			}
		}
	}
	spin_unlock_irqrestore (&hmidi->lock, flags);
	return 0;
}

static int snd_hdsp_midi_input_read (struct hdsp_midi *hmidi)
{
	unsigned char buf[128]; /* this buffer is designed to match the MIDI input FIFO size */
	unsigned long flags;
	int n_pending;
	int i;

	spin_lock_irqsave (&hmidi->lock, flags);
	if ((n_pending = snd_hdsp_midi_input_available (hmidi->hdsp, hmidi->id)) > 0) {
		if (hmidi->input) {
			if (n_pending > (int)sizeof (buf))
				n_pending = sizeof (buf);
			for (i = 0; i < n_pending; ++i)
				buf[i] = snd_hdsp_midi_read_byte (hmidi->hdsp, hmidi->id);
			if (n_pending)
				snd_rawmidi_receive (hmidi->input, buf, n_pending);
		} else {
			/* flush the MIDI input FIFO */
			while (--n_pending)
				snd_hdsp_midi_read_byte (hmidi->hdsp, hmidi->id);
		}
	}
	hmidi->pending = 0;
	if (hmidi->id)
		hmidi->hdsp->control_register |= HDSP_Midi1InterruptEnable;
	else
		hmidi->hdsp->control_register |= HDSP_Midi0InterruptEnable;
	hdsp_write(hmidi->hdsp, HDSP_controlRegister, hmidi->hdsp->control_register);
	spin_unlock_irqrestore (&hmidi->lock, flags);
	return snd_hdsp_midi_output_write (hmidi);
}

static void snd_hdsp_midi_input_trigger(struct snd_rawmidi_substream *substream, int up)
{
	struct hdsp *hdsp;
	struct hdsp_midi *hmidi;
	unsigned long flags;
	u32 ie;

	hmidi = (struct hdsp_midi *) substream->rmidi->private_data;
	hdsp = hmidi->hdsp;
	ie = hmidi->id ? HDSP_Midi1InterruptEnable : HDSP_Midi0InterruptEnable;
	spin_lock_irqsave (&hdsp->lock, flags);
	if (up) {
		if (!(hdsp->control_register & ie)) {
			snd_hdsp_flush_midi_input (hdsp, hmidi->id);
			hdsp->control_register |= ie;
		}
	} else {
		hdsp->control_register &= ~ie;
		tasklet_kill(&hdsp->midi_tasklet);
	}

	hdsp_write(hdsp, HDSP_controlRegister, hdsp->control_register);
	spin_unlock_irqrestore (&hdsp->lock, flags);
}

static void snd_hdsp_midi_output_timer(unsigned long data)
{
	struct hdsp_midi *hmidi = (struct hdsp_midi *) data;
	unsigned long flags;
	
	snd_hdsp_midi_output_write(hmidi);
	spin_lock_irqsave (&hmidi->lock, flags);

	/* this does not bump hmidi->istimer, because the