card.c

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/*
 *   (Tentative) USB Audio Driver for ALSA
 *
 *   Copyright (c) 2002 by Takashi Iwai <[email protected]>
 *
 *   Many codes borrowed from audio.c by
 *      Alan Cox ([email protected])
 *      Thomas Sailer ([email protected])
 *
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 *
 *  NOTES:
 *
 *   - async unlink should be used for avoiding the sleep inside lock.
 *     2.4.22 usb-uhci seems buggy for async unlinking and results in
 *     oops.  in such a cse, pass async_unlink=0 option.
 *   - the linked URBs would be preferred but not used so far because of
 *     the instability of unlinking.
 *   - type II is not supported properly.  there is no device which supports
 *     this type *correctly*.  SB extigy looks as if it supports, but it's
 *     indeed an AC3 stream packed in SPDIF frames (i.e. no real AC3 stream).
 */


#include <linux/bitops.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/ctype.h>
#include <linux/usb.h>
#include <linux/moduleparam.h>
#include <linux/mutex.h>
#include <linux/usb/audio.h>
#include <linux/usb/audio-v2.h>
#include <linux/module.h>

#include <sound/control.h>
#include <sound/core.h>
#include <sound/info.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/initval.h>

#include "usbaudio.h"
#include "card.h"
#include "midi.h"
#include "mixer.h"
#include "proc.h"
#include "quirks.h"
#include "endpoint.h"
#include "helper.h"
#include "debug.h"
#include "pcm.h"
#include "format.h"
#include "power.h"
#include "stream.h"

MODULE_AUTHOR("Takashi Iwai <[email protected]>");
MODULE_DESCRIPTION("USB Audio");
MODULE_LICENSE("GPL");
MODULE_SUPPORTED_DEVICE("{{Generic,USB Audio}}");


static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;  /* Index 0-MAX */
static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;   /* ID for this card */
static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;/* Enable this card */
/* Vendor/product IDs for this card */
static int vid[SNDRV_CARDS] = { [0 ... (SNDRV_CARDS-1)] = -1 };
static int pid[SNDRV_CARDS] = { [0 ... (SNDRV_CARDS-1)] = -1 };
static int nrpacks = 8;     /* max. number of packets per urb */
static bool async_unlink = 1;
static int device_setup[SNDRV_CARDS]; /* device parameter for this card */
static bool ignore_ctl_error;

module_param_array(index, int, NULL, 0444);
MODULE_PARM_DESC(index, "Index value for the USB audio adapter.");
module_param_array(id, charp, NULL, 0444);
MODULE_PARM_DESC(id, "ID string for the USB audio adapter.");
module_param_array(enable, bool, NULL, 0444);
MODULE_PARM_DESC(enable, "Enable USB audio adapter.");
module_param_array(vid, int, NULL, 0444);
MODULE_PARM_DESC(vid, "Vendor ID for the USB audio device.");
module_param_array(pid, int, NULL, 0444);
MODULE_PARM_DESC(pid, "Product ID for the USB audio device.");
module_param(nrpacks, int, 0644);
MODULE_PARM_DESC(nrpacks, "Max. number of packets per URB.");
module_param(async_unlink, bool, 0444);
MODULE_PARM_DESC(async_unlink, "Use async unlink mode.");
module_param_array(device_setup, int, NULL, 0444);
MODULE_PARM_DESC(device_setup, "Specific device setup (if needed).");
module_param(ignore_ctl_error, bool, 0444);
MODULE_PARM_DESC(ignore_ctl_error,
         "Ignore errors from USB controller for mixer interfaces.");

/*
 * we keep the snd_usb_audio_t instances by ourselves for merging
 * the all interfaces on the same card as one sound device.
 */

static DEFINE_MUTEX(register_mutex);
static struct snd_usb_audio *usb_chip[SNDRV_CARDS];
static struct usb_driver usb_audio_driver;

/*
 * disconnect streams
 * called from snd_usb_audio_disconnect()
 */
static void snd_usb_stream_disconnect(struct list_head *head)
{
    int idx;
    struct snd_usb_stream *as;
    struct snd_usb_substream *subs;

    as = list_entry(head, struct snd_usb_stream, list);
    for (idx = 0; idx < 2; idx++) {
        subs = &as->substream[idx];
        if (!subs->num_formats)
            continue;
        subs->interface = -1;
        subs->data_endpoint = NULL;
        subs->sync_endpoint = NULL;
    }
}

static int snd_usb_create_stream(struct snd_usb_audio *chip, int ctrlif, int interface)
{
    struct usb_device *dev = chip->dev;
    struct usb_host_interface *alts;
    struct usb_interface_descriptor *altsd;
    struct usb_interface *iface = usb_ifnum_to_if(dev, interface);

    if (!iface) {
        snd_printk(KERN_ERR "%d:%u:%d : does not exist\n",
               dev->devnum, ctrlif, interface);
        return -EINVAL;
    }

    if (usb_interface_claimed(iface)) {
        snd_printdd(KERN_INFO "%d:%d:%d: skipping, already claimed\n",
                        dev->devnum, ctrlif, interface);
        return -EINVAL;
    }

    alts = &iface->altsetting[0];
    altsd = get_iface_desc(alts);
    if ((altsd->bInterfaceClass == USB_CLASS_AUDIO ||
         altsd->bInterfaceClass == USB_CLASS_VENDOR_SPEC) &&
        altsd->bInterfaceSubClass == USB_SUBCLASS_MIDISTREAMING) {
        int err = snd_usbmidi_create(chip->card, iface,
                         &chip->midi_list, NULL);
        if (err < 0) {
            snd_printk(KERN_ERR "%d:%u:%d: cannot create sequencer device\n",
                        dev->devnum, ctrlif, interface);
            return -EINVAL;
        }
        usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);

        return 0;
    }

    if ((altsd->bInterfaceClass != USB_CLASS_AUDIO &&
         altsd->bInterfaceClass != USB_CLASS_VENDOR_SPEC) ||
        altsd->bInterfaceSubClass != USB_SUBCLASS_AUDIOSTREAMING) {
        snd_printdd(KERN_ERR "%d:%u:%d: skipping non-supported interface %d\n",
                    dev->devnum, ctrlif, interface, altsd->bInterfaceClass);
        /* skip non-supported classes */
        return -EINVAL;
    }

    if (snd_usb_get_speed(dev) == USB_SPEED_LOW) {
        snd_printk(KERN_ERR "low speed audio streaming not supported\n");
        return -EINVAL;
    }

    if (! snd_usb_parse_audio_interface(chip, interface)) {
        usb_set_interface(dev, interface, 0); /* reset the current interface */
        usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1L);
        return -EINVAL;
    }

    return 0;
}

/*
 * parse audio control descriptor and create pcm/midi streams
 */
static int snd_usb_create_streams(struct snd_usb_audio *chip, int ctrlif)
{
    struct usb_device *dev = chip->dev;
    struct usb_host_interface *host_iface;
    struct usb_interface_descriptor *altsd;
    void *control_header;
    int i, protocol;

    /* find audiocontrol interface */
    host_iface = &usb_ifnum_to_if(dev, ctrlif)->altsetting[0];
    control_header = snd_usb_find_csint_desc(host_iface->extra,
                         host_iface->extralen,
                         NULL, UAC_HEADER);
    altsd = get_iface_desc(host_iface);
    protocol = altsd->bInterfaceProtocol;

    if (!control_header) {
        snd_printk(KERN_ERR "cannot find UAC_HEADER\n");
        return -EINVAL;
    }

    switch (protocol) {
    default:
        snd_printdd(KERN_WARNING "unknown interface protocol %#02x, assuming v1\n",
                protocol);
        /* fall through */

    case UAC_VERSION_1: {
        struct uac1_ac_header_descriptor *h1 = control_header;

        if (!h1->bInCollection) {
            snd_printk(KERN_INFO "skipping empty audio interface (v1)\n");
            return -EINVAL;
        }

        if (h1->bLength < sizeof(*h1) + h1->bInCollection) {
            snd_printk(KERN_ERR "invalid UAC_HEADER (v1)\n");
            return -EINVAL;
        }

        for (i = 0; i < h1->bInCollection; i++)
            snd_usb_create_stream(chip, ctrlif, h1->baInterfaceNr[i]);

        break;
    }

    case UAC_VERSION_2: {
        struct usb_interface_assoc_descriptor *assoc =
            usb_ifnum_to_if(dev, ctrlif)->intf_assoc;

        if (!assoc) {
            snd_printk(KERN_ERR "Audio class v2 interfaces need an interface association\n");
            return -EINVAL;
        }

        for (i = 0; i < assoc->bInterfaceCount; i++) {
            int intf = assoc->bFirstInterface + i;

            if (intf != ctrlif)
                snd_usb_create_stream(chip, ctrlif, intf);
        }

        break;
    }
    }

    return 0;
}

/*
 * free the chip instance
 *
 * here we have to do not much, since pcm and controls are already freed
 *
 */

static int snd_usb_audio_free(struct snd_usb_audio *chip)
{
    mutex_destroy(&chip->mutex);
    kfree(chip);
    return 0;
}

static int snd_usb_audio_dev_free(struct snd_device *device)
{
    struct snd_usb_audio *chip = device->device_data;
    return snd_usb_audio_free(chip);
}

static void remove_trailing_spaces(char *str)
{
    char *p;

    if (!*str)
        return;
    for (p = str + strlen(str) - 1; p >= str && isspace(*p); p--)
        *p = 0;
}

/*
 * create a chip instance and set its names.
 */
static int snd_usb_audio_create(struct usb_device *dev, int idx,
                const struct snd_usb_audio_quirk *quirk,
                struct snd_usb_audio **rchip)
{
    struct snd_card *card;
    struct snd_usb_audio *chip;
    int err, len;
    char component[14];
    static struct snd_device_ops ops = {
        .dev_free = snd_usb_audio_dev_free,
    };

    *rchip = NULL;

    switch (snd_usb_get_speed(dev)) {
    case USB_SPEED_LOW:
    case USB_SPEED_FULL:
    case USB_SPEED_HIGH:
    case USB_SPEED_SUPER:
        break;
    default:
        snd_printk(KERN_ERR "unknown device speed %d\n", snd_usb_get_speed(dev));
        return -ENXIO;
    }

    err = snd_card_create(index[idx], id[idx], THIS_MODULE, 0, &card);
    if (err < 0) {
        snd_printk(KERN_ERR "cannot create card instance %d\n", idx);
        return err;
    }

    chip = kzalloc(sizeof(*chip), GFP_KERNEL);
    if (! chip) {
        snd_card_free(card);
        return -ENOMEM;
    }

    mutex_init(&chip->mutex);
    init_rwsem(&chip->shutdown_rwsem);
    chip->index = idx;
    chip->dev = dev;
    chip->card = card;
    chip->setup = device_setup[idx];
    chip->nrpacks = nrpacks;
    chip->async_unlink = async_unlink;
    chip->probing = 1;

    chip->usb_id = USB_ID(le16_to_cpu(dev->descriptor.idVendor),
                  le16_to_cpu(dev->descriptor.idProduct));
    INIT_LIST_HEAD(&chip->pcm_list);
    INIT_LIST_HEAD(&chip->ep_list);
    INIT_LIST_HEAD(&chip->midi_list);
    INIT_LIST_HEAD(&chip->mixer_list);

    if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops)) < 0) {
        snd_usb_audio_free(chip);
        snd_card_free(card);
        return err;
    }

    strcpy(card->driver, "USB-Audio");
    sprintf(component, "USB%04x:%04x",
        USB_ID_VENDOR(chip->usb_id), USB_ID_PRODUCT(chip->usb_id));
    snd_component_add(card, component);

    /* retrieve the device string as shortname */
    if (quirk && quirk->product_name && *quirk->product_name) {
        strlcpy(card->shortname, quirk->product_name, sizeof(card->shortname));
    } else {
        if (!dev->descriptor.iProduct ||
            usb_string(dev, dev->descriptor.iProduct,
            card->shortname, sizeof(card->shortname)) <= 0) {
            /* no name available from anywhere, so use ID */
            sprintf(card->shortname, "USB Device %#04x:%#04x",
                USB_ID_VENDOR(chip->usb_id),
                USB_ID_PRODUCT(chip->usb_id));
        }
    }
    remove_trailing_spaces(card->shortname);

    /* retrieve the vendor and device strings as longname */
    if (quirk && quirk->vendor_name && *quirk->vendor_name) {
        len = strlcpy(card->longname, quirk->vendor_name, sizeof(card->longname));
    } else {
        if (dev->descriptor.iManufacturer)
            len = usb_string(dev, dev->descriptor.iManufacturer,
                     card->longname, sizeof(card->longname));
        else
            len = 0;
        /* we don't really care if there isn't any vendor string */
    }
    if (len > 0) {
        remove_trailing_spaces(card->longname);
        if (*card->longname)
            strlcat(card->longname, " ", sizeof(card->longname));
    }

    strlcat(card->longname, card->shortname, sizeof(card->longname));

    len = strlcat(card->longname, " at ", sizeof(card->longname));

    if (len < sizeof(card->longname))
        usb_make_path(dev, card->longname + len, sizeof(card->longname) - len);

    switch (snd_usb_get_speed(dev)) {
    case USB_SPEED_LOW:
        strlcat(card->longname, ", low speed", sizeof(card->longname));
        break;
    case USB_SPEED_FULL:
        strlcat(card->longname, ", full speed", sizeof(card->longname));
        break;
    case USB_SPEED_HIGH:
        strlcat(card->longname, ", high speed", sizeof(card->longname));
        break;
    case USB_SPEED_SUPER:
        strlcat(card->longname, ", super speed", sizeof(card->longname));
        break;
    default:
        break;
    }

    snd_usb_audio_create_proc(chip);

    *rchip = chip;
    return 0;
}

/*
 * probe the active usb device
 *
 * note that this can be called multiple times per a device, when it
 * includes multiple audio control interfaces.
 *
 * thus we check the usb device pointer and creates the card instance
 * only at the first time.  the successive calls of this function will
 * append the pcm interface to the corresponding card.
 */
static struct snd_usb_audio *
snd_usb_audio_probe(struct usb_device *dev,
            struct usb_interface *intf,
            const struct usb_device_id *usb_id)
{
    const struct snd_usb_audio_quirk *quirk = (const struct snd_usb_audio_quirk *)usb_id->driver_info;
    int i, err;
    struct snd_usb_audio *chip;
    struct usb_host_interface *alts;
    int ifnum;
    u32 id;

    alts = &intf->altsetting[0];
    ifnum = get_iface_desc(alts)->bInterfaceNumber;
    id = USB_ID(le16_to_cpu(dev->descriptor.idVendor),
            le16_to_cpu(dev->descriptor.idProduct));
    if (quirk && quirk->ifnum >= 0 && ifnum != quirk->ifnum)
        goto __err_val;

    if (snd_usb_apply_boot_quirk(dev, intf, quirk) < 0)
        goto __err_val;

    /*
     * found a config.  now register to ALSA
     */

    /* check whether it's already registered */
    chip = NULL;
    mutex_lock(&register_mutex);
    for (i = 0; i < SNDRV_CARDS; i++) {
        if (usb_chip[i] && usb_chip[i]->dev == dev) {
            if (usb_chip[i]->shutdown) {
                snd_printk(KERN_ERR "USB device is in the shutdown state, cannot create a card instance\n");
                goto __error;
            }
            chip = usb_chip[i];
            chip->probing = 1;
            break;
        }
    }
    if (! chip) {
        /* it's a fresh one.
         * now look for an empty slot and create a new card instance
         */
        for (i = 0; i < SNDRV_CARDS; i++)
            if (enable[i] && ! usb_chip[i] &&
                (vid[i] == -1 || vid[i] == USB_ID_VENDOR(id)) &&
                (pid[i] == -1 || pid[i] == USB_ID_PRODUCT(id))) {
                if (snd_usb_audio_create(dev, i, quirk, &chip) < 0) {
                    goto __error;
                }
                snd_card_set_dev(chip->card, &intf->dev);
                chip->pm_intf = intf;
                break;
            }
        if (!chip) {
            printk(KERN_ERR "no available usb audio device\n");
            goto __error;
        }
    }

    /*
     * For devices with more than one control interface, we assume the
     * first contains the audio controls. We might need a more specific
     * check here in the future.
     */
    if (!chip->ctrl_intf)
        chip->ctrl_intf = alts;

    chip->txfr_quirk = 0;
    err = 1; /* continue */
    if (quirk && quirk->ifnum != QUIRK_NO_INTERFACE) {
        /* need some special handlings */
        if ((err = snd_usb_create_quirk(chip, intf, &usb_audio_driver, quirk)) < 0)
            goto __error;
    }

    if (err > 0) {
        /* create normal USB audio interfaces */
        if (snd_usb_create_streams(chip, ifnum) < 0 ||
            snd_usb_create_mixer(chip, ifnum, ignore_ctl_error) < 0) {
            goto __error;
        }
    }

    /* we are allowed to call snd_card_register() many times */
    if (snd_card_register(chip->card) < 0) {
        goto __error;
    }

    usb_chip[chip->index] = chip;
    chip->num_interfaces++;
    chip->probing = 0;
    mutex_unlock(&register_mutex);
    return chip;

 __error:
    if (chip) {
        if (!chip->num_interfaces)
            snd_card_free(chip->card);
        chip->probing = 0;
    }
    mutex_unlock(&register_mutex);
 __err_val:
    return NULL;
}

/*
 * we need to take care of counter, since disconnection can be called also
 * many times as well as usb_audio_probe().
 */
static void snd_usb_audio_disconnect(struct usb_device *dev,
                     struct snd_usb_audio *chip)
{
    struct snd_card *card;
    struct list_head *p, *n;

    if (chip == (void *)-1L)
        return;

    card = chip->card;
    down_write(&chip->shutdown_rwsem);
    chip->shutdown = 1;
    up_write(&chip->shutdown_rwsem);

    mutex_lock(&register_mutex);
    chip->num_interfaces--;
    if (chip->num_interfaces <= 0) {
        snd_card_disconnect(card);
        /* release the pcm resources */
        list_for_each(p, &chip->pcm_list) {
            snd_usb_stream_disconnect(p);
        }
        /* release the endpoint resources */
        list_for_each_safe(p, n, &chip->ep_list) {
            snd_usb_endpoint_free(p);
        }
        /* release the midi resources */
        list_for_each(p, &chip->midi_list) {
            snd_usbmidi_disconnect(p);
        }
        /* release mixer resources */
        list_for_each(p, &chip->mixer_list) {
            snd_usb_mixer_disconnect(p);
        }
        usb_chip[chip->index] = NULL;
        mutex_unlock(&register_mutex);
        snd_card_free_when_closed(card);
    } else {
        mutex_unlock(&register_mutex);
    }
}

/*
 * new 2.5 USB kernel API
 */
static int usb_audio_probe(struct usb_interface *intf,
               const struct usb_device_id *id)
{
    struct snd_usb_audio *chip;
    chip = snd_usb_audio_probe(interface_to_usbdev(intf), intf, id);
    if (chip) {
        usb_set_intfdata(intf, chip);
        return 0;
    } else
        return -EIO;
}

static void usb_audio_disconnect(struct usb_interface *intf)
{
    snd_usb_audio_disconnect(interface_to_usbdev(intf),
                 usb_get_intfdata(intf));
}

#ifdef CONFIG_PM

int snd_usb_autoresume(struct snd_usb_audio *chip)
{
    int err = -ENODEV;

    down_read(&chip->shutdown_rwsem);
    if (!chip->shutdown && !chip->probing)
        err = usb_autopm_get_interface(chip->pm_intf);
    up_read(&chip->shutdown_rwsem);

    return err;
}

void snd_usb_autosuspend(struct snd_usb_audio *chip)
{
    down_read(&chip->shutdown_rwsem);
    if (!chip->shutdown && !chip->probing)
        usb_autopm_put_interface(chip->pm_intf);
    up_read(&chip->shutdown_rwsem);
}

static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message)
{
    struct snd_usb_audio *chip = usb_get_intfdata(intf);
    struct list_head *p;
    struct snd_usb_stream *as;
    struct usb_mixer_interface *mixer;

    if (chip == (void *)-1L)
        return 0;

    if (!PMSG_IS_AUTO(message)) {
        snd_power_change_state(chip->card, SNDRV_CTL_POWER_D3hot);
        if (!chip->num_suspended_intf++) {
            list_for_each(p, &chip->pcm_list) {
                as = list_entry(p, struct snd_usb_stream, list);
                snd_pcm_suspend_all(as->pcm);
                as->substream[0].need_setup_ep =
                    as->substream[1].need_setup_ep = true;
            }
        }
    } else {
        /*
         * otherwise we keep the rest of the system in the dark
         * to keep this transparent
         */
        if (!chip->num_suspended_intf++)
            chip->autosuspended = 1;
    }

    list_for_each_entry(mixer, &chip->mixer_list, list)
        snd_usb_mixer_inactivate(mixer);

    return 0;
}

static int usb_audio_resume(struct usb_interface *intf)
{
    struct snd_usb_audio *chip = usb_get_intfdata(intf);
    struct usb_mixer_interface *mixer;
    int err = 0;

    if (chip == (void *)-1L)
        return 0;
    if (--chip->num_suspended_intf)
        return 0;
    /*
     * ALSA leaves material resumption to user space
     * we just notify and restart the mixers
     */
    list_for_each_entry(mixer, &chip->mixer_list, list) {
        err = snd_usb_mixer_activate(mixer);
        if (err < 0)
            goto err_out;
    }

    if (!chip->autosuspended)
        snd_power_change_state(chip->card, SNDRV_CTL_POWER_D0);
    chip->autosuspended = 0;

err_out:
    return err;
}
#else
#define usb_audio_suspend   NULL
#define usb_audio_resume    NULL
#endif      /* CONFIG_PM */

static struct usb_device_id usb_audio_ids [] = {
#include "quirks-table.h"
    { .match_flags = (USB_DEVICE_ID_MATCH_INT_CLASS | USB_DEVICE_ID_MATCH_INT_SUBCLASS),
      .bInterfaceClass = USB_CLASS_AUDIO,
      .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL },
    { }                     /* Terminating entry */
};

MODULE_DEVICE_TABLE (usb, usb_audio_ids);

/*
 * entry point for linux usb interface
 */

static struct usb_driver usb_audio_driver = {
    .name =     "snd-usb-audio",
    .probe =    usb_audio_probe,
    .disconnect =   usb_audio_disconnect,
    .suspend =  usb_audio_suspend,
    .resume =   usb_audio_resume,
    .id_table = usb_audio_ids,
    .supports_autosuspend = 1,
};

static int __init snd_usb_audio_init(void)
{
    if (nrpacks < 1 || nrpacks > MAX_PACKS) {
        printk(KERN_WARNING "invalid nrpacks value.\n");
        return -EINVAL;
    }
    return usb_register(&usb_audio_driver);
}

static void __exit snd_usb_audio_cleanup(void)
{
    usb_deregister(&usb_audio_driver);
}

module_init(snd_usb_audio_init);
module_exit(snd_usb_audio_cleanup);