hdsp.c

优龙2410linux2.6.8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 inline int hdsp_external_sample_rate (hdsp_t *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 inline int hdsp_spdif_sample_rate(hdsp_t *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 ("unknown spdif frequency status; bits = 0x%x, status = 0x%x\n", rate_bits, status);
	return 0;
}

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

static snd_pcm_uframes_t hdsp_hw_pointer(hdsp_t *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 -= 32;
	position &= (HDSP_CHANNEL_BUFFER_SAMPLES-1);
	return position;
}

static inline void hdsp_reset_hw_pointer(hdsp_t *hdsp)
{
	hdsp_write (hdsp, HDSP_resetPointer, 0);
}

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

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

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

static int hdsp_set_interrupt_interval(hdsp_t *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 int hdsp_set_rate(hdsp_t *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("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("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("Detected ADAT in quad speed mode\n");			
			} else if (rate != external_freq) {
				snd_printk("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 ("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);

	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;
}

static void hdsp_set_thru(hdsp_t *hdsp, int channel, int enable)
{

	hdsp->passthru = 0;

	if (channel < 0) {

		int i;

		/* set thru for all channels */

		if (enable) {
			for (i = 0; i < hdsp->max_channels; i++) {
				hdsp_write_gain (hdsp, hdsp_input_to_output_key(hdsp,i,i), UNITY_GAIN);
			}
		} else {
			for (i = 0; i < hdsp->max_channels; i++) {
				hdsp_write_gain (hdsp, hdsp_input_to_output_key(hdsp,i,i), MINUS_INFINITY_GAIN);
			}
		}

	} else {
		int mapped_channel;

		snd_assert(channel < hdsp->max_channels, return);

		mapped_channel = hdsp->channel_map[channel];

		snd_assert(mapped_channel > -1, return);

		if (enable) {
			hdsp_write_gain (hdsp, hdsp_input_to_output_key(hdsp,mapped_channel,mapped_channel), UNITY_GAIN);
		} else {
			hdsp_write_gain (hdsp, hdsp_input_to_output_key(hdsp,mapped_channel,mapped_channel), MINUS_INFINITY_GAIN);
		}
	}
}

static int hdsp_set_passthru(hdsp_t *hdsp, int onoff)
{
	if (onoff) {
		hdsp_set_thru(hdsp, -1, 1);
		hdsp_reset_hw_pointer(hdsp);
		hdsp_silence_playback(hdsp);

		/* we don't want interrupts, so do a
		   custom version of hdsp_start_audio().
		*/

		hdsp->control_register |= (HDSP_Start|HDSP_AudioInterruptEnable|hdsp_encode_latency(7));

		hdsp_write(hdsp, HDSP_controlRegister, hdsp->control_register);
		hdsp->passthru = 1;
	} else {
		hdsp_set_thru(hdsp, -1, 0);
		hdsp_stop_audio(hdsp);		
		hdsp->passthru = 0;
	}

	return 0;
}

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

static inline unsigned char snd_hdsp_midi_read_byte (hdsp_t *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 inline void snd_hdsp_midi_write_byte (hdsp_t *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 inline int snd_hdsp_midi_input_available (hdsp_t *hdsp, int id)
{
	if (id) {
		return (hdsp_read(hdsp, HDSP_midiStatusIn1) & 0xff);
	} else {
		return (hdsp_read(hdsp, HDSP_midiStatusIn0) & 0xff);
	}
}

static inline int snd_hdsp_midi_output_possible (hdsp_t *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 inline void snd_hdsp_flush_midi_input (hdsp_t *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 (hdsp_midi_t *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 (hdsp_midi_t *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) {