serial-u16550.c

来自「linux 内核源代码」· C语言 代码 · 共 1,050 行 · 第 1/3 页

					/* If this substream of the data is
					 * different previous substream
					 * in this uart, send the change part
					 * event
					 */
					uart->prev_out = substream->number;
					/* change part */
					snd_uart16550_output_byte(uart, substream,
								  0xf5);
					/* data */
					snd_uart16550_output_byte(uart, substream,
								  uart->prev_out + 1);
					/* If midi_byte is a data byte,
					 * send the previous status byte */
					if (midi_byte < 0x80 &&
					    uart->adaptor == SNDRV_SERIAL_SOUNDCANVAS)
						snd_uart16550_output_byte(uart, substream, uart->prev_status[uart->prev_out]);
				} else if (!uart->drop_on_full)
					break;

			}

			/* send midi byte */
			if (!snd_uart16550_output_byte(uart, substream, midi_byte) &&
			    !uart->drop_on_full )
				break;

			if (midi_byte >= 0x80 && midi_byte < 0xf0)
				uart->prev_status[uart->prev_out] = midi_byte;
			first = 1;

			snd_rawmidi_transmit_ack( substream, 1 );
		}
		lasttime = jiffies;
	}
	spin_unlock_irqrestore(&uart->open_lock, flags);
}

static void snd_uart16550_output_trigger(struct snd_rawmidi_substream *substream,
					 int up)
{
	unsigned long flags;
	struct snd_uart16550 *uart = substream->rmidi->private_data;

	spin_lock_irqsave(&uart->open_lock, flags);
	if (up)
		uart->filemode |= SERIAL_MODE_OUTPUT_TRIGGERED;
	else
		uart->filemode &= ~SERIAL_MODE_OUTPUT_TRIGGERED;
	spin_unlock_irqrestore(&uart->open_lock, flags);
	if (up)
		snd_uart16550_output_write(substream);
}

static struct snd_rawmidi_ops snd_uart16550_output =
{
	.open =		snd_uart16550_output_open,
	.close =	snd_uart16550_output_close,
	.trigger =	snd_uart16550_output_trigger,
};

static struct snd_rawmidi_ops snd_uart16550_input =
{
	.open =		snd_uart16550_input_open,
	.close =	snd_uart16550_input_close,
	.trigger =	snd_uart16550_input_trigger,
};

static int snd_uart16550_free(struct snd_uart16550 *uart)
{
	if (uart->irq >= 0)
		free_irq(uart->irq, uart);
	release_and_free_resource(uart->res_base);
	kfree(uart);
	return 0;
};

static int snd_uart16550_dev_free(struct snd_device *device)
{
	struct snd_uart16550 *uart = device->device_data;
	return snd_uart16550_free(uart);
}

static int __devinit snd_uart16550_create(struct snd_card *card,
				       unsigned long iobase,
				       int irq,
				       unsigned int speed,
				       unsigned int base,
				       int adaptor,
				       int droponfull,
				       struct snd_uart16550 **ruart)
{
	static struct snd_device_ops ops = {
		.dev_free =	snd_uart16550_dev_free,
	};
	struct snd_uart16550 *uart;
	int err;


	if ((uart = kzalloc(sizeof(*uart), GFP_KERNEL)) == NULL)
		return -ENOMEM;
	uart->adaptor = adaptor;
	uart->card = card;
	spin_lock_init(&uart->open_lock);
	uart->irq = -1;
	uart->base = iobase;
	uart->drop_on_full = droponfull;

	if ((err = snd_uart16550_detect(uart)) <= 0) {
		printk(KERN_ERR "no UART detected at 0x%lx\n", iobase);
		snd_uart16550_free(uart);
		return -ENODEV;
	}

	if (irq >= 0 && irq != SNDRV_AUTO_IRQ) {
		if (request_irq(irq, snd_uart16550_interrupt,
				IRQF_DISABLED, "Serial MIDI", uart)) {
			snd_printk("irq %d busy. Using Polling.\n", irq);
		} else {
			uart->irq = irq;
		}
	}
	uart->divisor = base / speed;
	uart->speed = base / (unsigned int)uart->divisor;
	uart->speed_base = base;
	uart->prev_out = -1;
	uart->prev_in = 0;
	uart->rstatus = 0;
	memset(uart->prev_status, 0x80, sizeof(unsigned char) * SNDRV_SERIAL_MAX_OUTS);
	init_timer(&uart->buffer_timer);
	uart->buffer_timer.function = snd_uart16550_buffer_timer;
	uart->buffer_timer.data = (unsigned long)uart;
	uart->timer_running = 0;

	/* Register device */
	if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, uart, &ops)) < 0) {
		snd_uart16550_free(uart);
		return err;
	}

	switch (uart->adaptor) {
	case SNDRV_SERIAL_MS124W_SA:
	case SNDRV_SERIAL_MS124W_MB:
		/* MS-124W can draw power from RTS and DTR if they
		   are in opposite states. */ 
		outb(UART_MCR_RTS | (0&UART_MCR_DTR), uart->base + UART_MCR);
		break;
	case SNDRV_SERIAL_MS124T:
		/* MS-124T can draw power from RTS and/or DTR (preferably
		   both) if they are asserted. */
		outb(UART_MCR_RTS | UART_MCR_DTR, uart->base + UART_MCR);
		break;
	default:
		break;
	}

	if (ruart)
		*ruart = uart;

	return 0;
}

static void __devinit snd_uart16550_substreams(struct snd_rawmidi_str *stream)
{
	struct snd_rawmidi_substream *substream;

	list_for_each_entry(substream, &stream->substreams, list) {
		sprintf(substream->name, "Serial MIDI %d", substream->number + 1);
	}
}

static int __devinit snd_uart16550_rmidi(struct snd_uart16550 *uart, int device,
				      int outs, int ins,
				      struct snd_rawmidi **rmidi)
{
	struct snd_rawmidi *rrawmidi;
	int err;

	err = snd_rawmidi_new(uart->card, "UART Serial MIDI", device,
			      outs, ins, &rrawmidi);
	if (err < 0)
		return err;
	snd_rawmidi_set_ops(rrawmidi, SNDRV_RAWMIDI_STREAM_INPUT,
			    &snd_uart16550_input);
	snd_rawmidi_set_ops(rrawmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
			    &snd_uart16550_output);
	strcpy(rrawmidi->name, "Serial MIDI");
	snd_uart16550_substreams(&rrawmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT]);
	snd_uart16550_substreams(&rrawmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT]);
	rrawmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
			       SNDRV_RAWMIDI_INFO_INPUT |
			       SNDRV_RAWMIDI_INFO_DUPLEX;
	rrawmidi->private_data = uart;
	if (rmidi)
		*rmidi = rrawmidi;
	return 0;
}

static int __devinit snd_serial_probe(struct platform_device *devptr)
{
	struct snd_card *card;
	struct snd_uart16550 *uart;
	int err;
	int dev = devptr->id;

	switch (adaptor[dev]) {
	case SNDRV_SERIAL_SOUNDCANVAS:
		ins[dev] = 1;
		break;
	case SNDRV_SERIAL_MS124T:
	case SNDRV_SERIAL_MS124W_SA:
		outs[dev] = 1;
		ins[dev] = 1;
		break;
	case SNDRV_SERIAL_MS124W_MB:
		outs[dev] = 16;
		ins[dev] = 1;
		break;
	case SNDRV_SERIAL_GENERIC:
		break;
	default:
		snd_printk("Adaptor type is out of range 0-%d (%d)\n",
			   SNDRV_SERIAL_MAX_ADAPTOR, adaptor[dev]);
		return -ENODEV;
	}

	if (outs[dev] < 1 || outs[dev] > SNDRV_SERIAL_MAX_OUTS) {
		snd_printk("Count of outputs is out of range 1-%d (%d)\n",
			   SNDRV_SERIAL_MAX_OUTS, outs[dev]);
		return -ENODEV;
	}

	if (ins[dev] < 1 || ins[dev] > SNDRV_SERIAL_MAX_INS) {
		snd_printk("Count of inputs is out of range 1-%d (%d)\n",
			   SNDRV_SERIAL_MAX_INS, ins[dev]);
		return -ENODEV;
	}

	card  = snd_card_new(index[dev], id[dev], THIS_MODULE, 0);
	if (card == NULL)
		return -ENOMEM;

	strcpy(card->driver, "Serial");
	strcpy(card->shortname, "Serial MIDI (UART16550A)");

	if ((err = snd_uart16550_create(card,
					port[dev],
					irq[dev],
					speed[dev],
					base[dev],
					adaptor[dev],
					droponfull[dev],
					&uart)) < 0)
		goto _err;

	err = snd_uart16550_rmidi(uart, 0, outs[dev], ins[dev], &uart->rmidi);
	if (err < 0)
		goto _err;

	sprintf(card->longname, "%s at 0x%lx, irq %d speed %d div %d outs %d ins %d adaptor %s droponfull %d",
		card->shortname,
		uart->base,
		uart->irq,
		uart->speed,
		(int)uart->divisor,
		outs[dev],
		ins[dev],
		adaptor_names[uart->adaptor],
		uart->drop_on_full);

	snd_card_set_dev(card, &devptr->dev);

	if ((err = snd_card_register(card)) < 0)
		goto _err;

	platform_set_drvdata(devptr, card);
	return 0;

 _err:
	snd_card_free(card);
	return err;
}

static int __devexit snd_serial_remove(struct platform_device *devptr)
{
	snd_card_free(platform_get_drvdata(devptr));
	platform_set_drvdata(devptr, NULL);
	return 0;
}

#define SND_SERIAL_DRIVER	"snd_serial_u16550"

static struct platform_driver snd_serial_driver = {
	.probe		= snd_serial_probe,
	.remove		= __devexit_p( snd_serial_remove),
	.driver		= {
		.name	= SND_SERIAL_DRIVER
	},
};

static void snd_serial_unregister_all(void)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(devices); ++i)
		platform_device_unregister(devices[i]);
	platform_driver_unregister(&snd_serial_driver);
}

static int __init alsa_card_serial_init(void)
{
	int i, cards, err;

	if ((err = platform_driver_register(&snd_serial_driver)) < 0)
		return err;

	cards = 0;
	for (i = 0; i < SNDRV_CARDS; i++) {
		struct platform_device *device;
		if (! enable[i])
			continue;
		device = platform_device_register_simple(SND_SERIAL_DRIVER,
							 i, NULL, 0);
		if (IS_ERR(device))
			continue;
		if (!platform_get_drvdata(device)) {
			platform_device_unregister(device);
			continue;
		}
		devices[i] = device;
		cards++;
	}
	if (! cards) {
#ifdef MODULE
		printk(KERN_ERR "serial midi soundcard not found or device busy\n");
#endif
		snd_serial_unregister_all();
		return -ENODEV;
	}
	return 0;
}

static void __exit alsa_card_serial_exit(void)
{
	snd_serial_unregister_all();
}

module_init(alsa_card_serial_init)
module_exit(alsa_card_serial_exit)