mpu401.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Driver for generic MPU-401 boards (UART mode only)
 *  Copyright (c) by Jaroslav Kysela <[email protected]>
 *  Copyright (c) 2004 by Castet Matthieu <[email protected]>
 */

#include <linux/init.h>
#include <linux/pnp.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/module.h>
#include <sound/core.h>
#include <sound/mpu401.h>
#include <sound/initval.h>

MODULE_AUTHOR("Jaroslav Kysela <[email protected]>");
MODULE_DESCRIPTION("MPU-401 UART");
MODULE_LICENSE("GPL");

static int index[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = -2}; /* exclude the first card */
static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;	/* ID for this card */
static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE;	/* Enable this card */
#ifdef CONFIG_PNP
static bool pnp[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};
#endif
static long port[SNDRV_CARDS] = SNDRV_DEFAULT_PORT;	/* MPU-401 port number */
static int irq[SNDRV_CARDS] = SNDRV_DEFAULT_IRQ;	/* MPU-401 IRQ */
static bool uart_enter[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};

module_param_array(index, int, NULL, 0444);
MODULE_PARM_DESC(index, "Index value for MPU-401 device.");
module_param_array(id, charp, NULL, 0444);
MODULE_PARM_DESC(id, "ID string for MPU-401 device.");
module_param_array(enable, bool, NULL, 0444);
MODULE_PARM_DESC(enable, "Enable MPU-401 device.");
#ifdef CONFIG_PNP
module_param_array(pnp, bool, NULL, 0444);
MODULE_PARM_DESC(pnp, "PnP detection for MPU-401 device.");
#endif
module_param_hw_array(port, long, ioport, NULL, 0444);
MODULE_PARM_DESC(port, "Port # for MPU-401 device.");
module_param_hw_array(irq, int, irq, NULL, 0444);
MODULE_PARM_DESC(irq, "IRQ # for MPU-401 device.");
module_param_array(uart_enter, bool, NULL, 0444);
MODULE_PARM_DESC(uart_enter, "Issue UART_ENTER command at open.");

static struct platform_device *platform_devices[SNDRV_CARDS];
static int pnp_registered;
static unsigned int snd_mpu401_devices;

static int snd_mpu401_create(struct device *devptr, int dev,
			     struct snd_card **rcard)
{
	struct snd_card *card;
	int err;

	if (!uart_enter[dev])
		dev_err(devptr, "the uart_enter option is obsolete; remove it\n");

	*rcard = NULL;
	err = snd_devm_card_new(devptr, index[dev], id[dev], THIS_MODULE,
				0, &card);
	if (err < 0)
		return err;
	strscpy(card->driver, "MPU-401 UART");
	strscpy(card->shortname, card->driver);
	sprintf(card->longname, "%s at %#lx, ", card->shortname, port[dev]);
	if (irq[dev] >= 0) {
		sprintf(card->longname + strlen(card->longname), "irq %d", irq[dev]);
	} else {
		strcat(card->longname, "polled");
	}

	err = snd_mpu401_uart_new(card, 0, MPU401_HW_MPU401, port[dev], 0,
				  irq[dev], NULL);
	if (err < 0) {
		dev_err(devptr, "MPU401 not detected at 0x%lx\n", port[dev]);
		return err;
	}

	*rcard = card;
	return 0;
}

static int snd_mpu401_probe(struct platform_device *devptr)
{
	int dev = devptr->id;
	int err;
	struct snd_card *card;

	if (port[dev] == SNDRV_AUTO_PORT) {
		dev_err(&devptr->dev, "specify port\n");
		return -EINVAL;
	}
	if (irq[dev] == SNDRV_AUTO_IRQ) {
		dev_err(&devptr->dev, "specify or disable IRQ\n");
		return -EINVAL;
	}
	err = snd_mpu401_create(&devptr->dev, dev, &card);
	if (err < 0)
		return err;
	err = snd_card_register(card);
	if (err < 0)
		return err;
	platform_set_drvdata(devptr, card);
	return 0;
}

#define SND_MPU401_DRIVER	"snd_mpu401"

static struct platform_driver snd_mpu401_driver = {
	.probe		= snd_mpu401_probe,
	.driver		= {
		.name	= SND_MPU401_DRIVER,
	},
};


#ifdef CONFIG_PNP

#define IO_EXTENT 2

static const struct pnp_device_id snd_mpu401_pnpids[] = {
	{ .id = "PNPb006" },
	{ .id = "" }
};

MODULE_DEVICE_TABLE(pnp, snd_mpu401_pnpids);

static int snd_mpu401_pnp(int dev, struct pnp_dev *device,
			  const struct pnp_device_id *id)
{
	if (!pnp_port_valid(device, 0) ||
	    pnp_port_flags(device, 0) & IORESOURCE_DISABLED) {
		dev_err(&device->dev, "no PnP port\n");
		return -ENODEV;
	}
	if (pnp_port_len(device, 0) < IO_EXTENT) {
		dev_err(&device->dev, "PnP port length is %llu, expected %d\n",
			   (unsigned long long)pnp_port_len(device, 0),
			   IO_EXTENT);
		return -ENODEV;
	}
	port[dev] = pnp_port_start(device, 0);

	if (!pnp_irq_valid(device, 0) ||
	    pnp_irq_flags(device, 0) & IORESOURCE_DISABLED) {
		dev_warn(&device->dev, "no PnP irq, using polling\n");
		irq[dev] = -1;
	} else {
		irq[dev] = pnp_irq(device, 0);
	}
	return 0;
}

static int snd_mpu401_pnp_probe(struct pnp_dev *pnp_dev,
				const struct pnp_device_id *id)
{
	static int dev;
	struct snd_card *card;
	int err;

	for ( ; dev < SNDRV_CARDS; ++dev) {
		if (!enable[dev] || !pnp[dev])
			continue;
		err = snd_mpu401_pnp(dev, pnp_dev, id);
		if (err < 0)
			return err;
		err = snd_mpu401_create(&pnp_dev->dev, dev, &card);
		if (err < 0)
			return err;
		err = snd_card_register(card);
		if (err < 0)
			return err;
		pnp_set_drvdata(pnp_dev, card);
		snd_mpu401_devices++;
		++dev;
		return 0;
	}
	return -ENODEV;
}

static struct pnp_driver snd_mpu401_pnp_driver = {
	.name = "mpu401",
	.id_table = snd_mpu401_pnpids,
	.probe = snd_mpu401_pnp_probe,
};
#else
static struct pnp_driver snd_mpu401_pnp_driver;
#endif

static void snd_mpu401_unregister_all(void)
{
	int i;

	if (pnp_registered)
		pnp_unregister_driver(&snd_mpu401_pnp_driver);
	for (i = 0; i < ARRAY_SIZE(platform_devices); ++i)
		platform_device_unregister(platform_devices[i]);
	platform_driver_unregister(&snd_mpu401_driver);
}

static int __init alsa_card_mpu401_init(void)
{
	int i, err;

	err = platform_driver_register(&snd_mpu401_driver);
	if (err < 0)
		return err;

	for (i = 0; i < SNDRV_CARDS; i++) {
		struct platform_device *device;
		if (! enable[i])
			continue;
#ifdef CONFIG_PNP
		if (pnp[i])
			continue;
#endif
		device = platform_device_register_simple(SND_MPU401_DRIVER,
							 i, NULL, 0);
		if (IS_ERR(device))
			continue;
		if (!platform_get_drvdata(device)) {
			platform_device_unregister(device);
			continue;
		}
		platform_devices[i] = device;
		snd_mpu401_devices++;
	}
	err = pnp_register_driver(&snd_mpu401_pnp_driver);
	if (!err)
		pnp_registered = 1;

	if (!snd_mpu401_devices) {
#ifdef MODULE
		pr_err("MPU-401 device not found or device busy\n");
#endif
		snd_mpu401_unregister_all();
		return -ENODEV;
	}
	return 0;
}

static void __exit alsa_card_mpu401_exit(void)
{
	snd_mpu401_unregister_all();
}

module_init(alsa_card_mpu401_init)
module_exit(alsa_card_mpu401_exit)