bfusb.c

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/*
 *
 *  AVM BlueFRITZ! USB driver
 *
 *  Copyright (C) 2003-2006  Marcel Holtmann <[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
 *
 */

#include <linux/module.h>

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/skbuff.h>

#include <linux/device.h>
#include <linux/firmware.h>

#include <linux/usb.h>

#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>

#define VERSION "1.2"

static struct usb_driver bfusb_driver;

static struct usb_device_id bfusb_table[] = {
    /* AVM BlueFRITZ! USB */
    { USB_DEVICE(0x057c, 0x2200) },

    { } /* Terminating entry */
};

MODULE_DEVICE_TABLE(usb, bfusb_table);

#define BFUSB_MAX_BLOCK_SIZE    256

#define BFUSB_BLOCK_TIMEOUT 3000

#define BFUSB_TX_PROCESS    1
#define BFUSB_TX_WAKEUP     2

#define BFUSB_MAX_BULK_TX   2
#define BFUSB_MAX_BULK_RX   2

struct bfusb_data {
    struct hci_dev      *hdev;

    unsigned long       state;

    struct usb_device   *udev;

    unsigned int        bulk_in_ep;
    unsigned int        bulk_out_ep;
    unsigned int        bulk_pkt_size;

    rwlock_t        lock;

    struct sk_buff_head transmit_q;

    struct sk_buff      *reassembly;

    atomic_t        pending_tx;
    struct sk_buff_head pending_q;
    struct sk_buff_head completed_q;
};

struct bfusb_data_scb {
    struct urb *urb;
};

static void bfusb_tx_complete(struct urb *urb);
static void bfusb_rx_complete(struct urb *urb);

static struct urb *bfusb_get_completed(struct bfusb_data *data)
{
    struct sk_buff *skb;
    struct urb *urb = NULL;

    BT_DBG("bfusb %p", data);

    skb = skb_dequeue(&data->completed_q);
    if (skb) {
        urb = ((struct bfusb_data_scb *) skb->cb)->urb;
        kfree_skb(skb);
    }

    return urb;
}

static void bfusb_unlink_urbs(struct bfusb_data *data)
{
    struct sk_buff *skb;
    struct urb *urb;

    BT_DBG("bfusb %p", data);

    while ((skb = skb_dequeue(&data->pending_q))) {
        urb = ((struct bfusb_data_scb *) skb->cb)->urb;
        usb_kill_urb(urb);
        skb_queue_tail(&data->completed_q, skb);
    }

    while ((urb = bfusb_get_completed(data)))
        usb_free_urb(urb);
}

static int bfusb_send_bulk(struct bfusb_data *data, struct sk_buff *skb)
{
    struct bfusb_data_scb *scb = (void *) skb->cb;
    struct urb *urb = bfusb_get_completed(data);
    int err, pipe;

    BT_DBG("bfusb %p skb %p len %d", data, skb, skb->len);

    if (!urb && !(urb = usb_alloc_urb(0, GFP_ATOMIC)))
        return -ENOMEM;

    pipe = usb_sndbulkpipe(data->udev, data->bulk_out_ep);

    usb_fill_bulk_urb(urb, data->udev, pipe, skb->data, skb->len,
            bfusb_tx_complete, skb);

    scb->urb = urb;

    skb_queue_tail(&data->pending_q, skb);

    err = usb_submit_urb(urb, GFP_ATOMIC);
    if (err) {
        BT_ERR("%s bulk tx submit failed urb %p err %d", 
                    data->hdev->name, urb, err);
        skb_unlink(skb, &data->pending_q);
        usb_free_urb(urb);
    } else
        atomic_inc(&data->pending_tx);

    return err;
}

static void bfusb_tx_wakeup(struct bfusb_data *data)
{
    struct sk_buff *skb;

    BT_DBG("bfusb %p", data);

    if (test_and_set_bit(BFUSB_TX_PROCESS, &data->state)) {
        set_bit(BFUSB_TX_WAKEUP, &data->state);
        return;
    }

    do {
        clear_bit(BFUSB_TX_WAKEUP, &data->state);

        while ((atomic_read(&data->pending_tx) < BFUSB_MAX_BULK_TX) &&
                (skb = skb_dequeue(&data->transmit_q))) {
            if (bfusb_send_bulk(data, skb) < 0) {
                skb_queue_head(&data->transmit_q, skb);
                break;
            }
        }

    } while (test_bit(BFUSB_TX_WAKEUP, &data->state));

    clear_bit(BFUSB_TX_PROCESS, &data->state);
}

static void bfusb_tx_complete(struct urb *urb)
{
    struct sk_buff *skb = (struct sk_buff *) urb->context;
    struct bfusb_data *data = (struct bfusb_data *) skb->dev;

    BT_DBG("bfusb %p urb %p skb %p len %d", data, urb, skb, skb->len);

    atomic_dec(&data->pending_tx);

    if (!test_bit(HCI_RUNNING, &data->hdev->flags))
        return;

    if (!urb->status)
        data->hdev->stat.byte_tx += skb->len;
    else
        data->hdev->stat.err_tx++;

    read_lock(&data->lock);

    skb_unlink(skb, &data->pending_q);
    skb_queue_tail(&data->completed_q, skb);

    bfusb_tx_wakeup(data);

    read_unlock(&data->lock);
}


static int bfusb_rx_submit(struct bfusb_data *data, struct urb *urb)
{
    struct bfusb_data_scb *scb;
    struct sk_buff *skb;
    int err, pipe, size = HCI_MAX_FRAME_SIZE + 32;

    BT_DBG("bfusb %p urb %p", data, urb);

    if (!urb && !(urb = usb_alloc_urb(0, GFP_ATOMIC)))
        return -ENOMEM;

    skb = bt_skb_alloc(size, GFP_ATOMIC);
    if (!skb) {
        usb_free_urb(urb);
        return -ENOMEM;
    }

    skb->dev = (void *) data;

    scb = (struct bfusb_data_scb *) skb->cb;
    scb->urb = urb;

    pipe = usb_rcvbulkpipe(data->udev, data->bulk_in_ep);

    usb_fill_bulk_urb(urb, data->udev, pipe, skb->data, size,
            bfusb_rx_complete, skb);

    skb_queue_tail(&data->pending_q, skb);

    err = usb_submit_urb(urb, GFP_ATOMIC);
    if (err) {
        BT_ERR("%s bulk rx submit failed urb %p err %d",
                    data->hdev->name, urb, err);
        skb_unlink(skb, &data->pending_q);
        kfree_skb(skb);
        usb_free_urb(urb);
    }

    return err;
}

static inline int bfusb_recv_block(struct bfusb_data *data, int hdr, unsigned char *buf, int len)
{
    BT_DBG("bfusb %p hdr 0x%02x data %p len %d", data, hdr, buf, len);

    if (hdr & 0x10) {
        BT_ERR("%s error in block", data->hdev->name);
        kfree_skb(data->reassembly);
        data->reassembly = NULL;
        return -EIO;
    }

    if (hdr & 0x04) {
        struct sk_buff *skb;
        unsigned char pkt_type;
        int pkt_len = 0;

        if (data->reassembly) {
            BT_ERR("%s unexpected start block", data->hdev->name);
            kfree_skb(data->reassembly);
            data->reassembly = NULL;
        }

        if (len < 1) {
            BT_ERR("%s no packet type found", data->hdev->name);
            return -EPROTO;
        }

        pkt_type = *buf++; len--;

        switch (pkt_type) {
        case HCI_EVENT_PKT:
            if (len >= HCI_EVENT_HDR_SIZE) {
                struct hci_event_hdr *hdr = (struct hci_event_hdr *) buf;
                pkt_len = HCI_EVENT_HDR_SIZE + hdr->plen;
            } else {
                BT_ERR("%s event block is too short", data->hdev->name);
                return -EILSEQ;
            }
            break;

        case HCI_ACLDATA_PKT:
            if (len >= HCI_ACL_HDR_SIZE) {
                struct hci_acl_hdr *hdr = (struct hci_acl_hdr *) buf;
                pkt_len = HCI_ACL_HDR_SIZE + __le16_to_cpu(hdr->dlen);
            } else {
                BT_ERR("%s data block is too short", data->hdev->name);
                return -EILSEQ;
            }
            break;

        case HCI_SCODATA_PKT:
            if (len >= HCI_SCO_HDR_SIZE) {
                struct hci_sco_hdr *hdr = (struct hci_sco_hdr *) buf;
                pkt_len = HCI_SCO_HDR_SIZE + hdr->dlen;
            } else {
                BT_ERR("%s audio block is too short", data->hdev->name);
                return -EILSEQ;
            }
            break;
        }

        skb = bt_skb_alloc(pkt_len, GFP_ATOMIC);
        if (!skb) {
            BT_ERR("%s no memory for the packet", data->hdev->name);
            return -ENOMEM;
        }

        skb->dev = (void *) data->hdev;
        bt_cb(skb)->pkt_type = pkt_type;

        data->reassembly = skb;
    } else {
        if (!data->reassembly) {
            BT_ERR("%s unexpected continuation block", data->hdev->name);
            return -EIO;
        }
    }

    if (len > 0)
        memcpy(skb_put(data->reassembly, len), buf, len);

    if (hdr & 0x08) {
        hci_recv_frame(data->reassembly);
        data->reassembly = NULL;
    }

    return 0;
}

static void bfusb_rx_complete(struct urb *urb)
{
    struct sk_buff *skb = (struct sk_buff *) urb->context;
    struct bfusb_data *data = (struct bfusb_data *) skb->dev;
    unsigned char *buf = urb->transfer_buffer;
    int count = urb->actual_length;
    int err, hdr, len;

    BT_DBG("bfusb %p urb %p skb %p len %d", data, urb, skb, skb->len);

    read_lock(&data->lock);

    if (!test_bit(HCI_RUNNING, &data->hdev->flags))
        goto unlock;

    if (urb->status || !count)
        goto resubmit;

    data->hdev->stat.byte_rx += count;

    skb_put(skb, count);

    while (count) {
        hdr = buf[0] | (buf[1] << 8);

        if (hdr & 0x4000) {
            len = 0;
            count -= 2;
            buf   += 2;
        } else {
            len = (buf[2] == 0) ? 256 : buf[2];
            count -= 3;
            buf   += 3;
        }

        if (count < len) {
            BT_ERR("%s block extends over URB buffer ranges",
                    data->hdev->name);
        }

        if ((hdr & 0xe1) == 0xc1)
            bfusb_recv_block(data, hdr, buf, len);

        count -= len;
        buf   += len;
    }

    skb_unlink(skb, &data->pending_q);
    kfree_skb(skb);

    bfusb_rx_submit(data, urb);

    read_unlock(&data->lock);

    return;

resubmit:
    urb->dev = data->udev;

    err = usb_submit_urb(urb, GFP_ATOMIC);
    if (err) {
        BT_ERR("%s bulk resubmit failed urb %p err %d",
                    data->hdev->name, urb, err);
    }

unlock:
    read_unlock(&data->lock);
}

static int bfusb_open(struct hci_dev *hdev)
{
    struct bfusb_data *data = hci_get_drvdata(hdev);
    unsigned long flags;
    int i, err;

    BT_DBG("hdev %p bfusb %p", hdev, data);

    if (test_and_set_bit(HCI_RUNNING, &hdev->flags))
        return 0;

    write_lock_irqsave(&data->lock, flags);

    err = bfusb_rx_submit(data, NULL);
    if (!err) {
        for (i = 1; i < BFUSB_MAX_BULK_RX; i++)
            bfusb_rx_submit(data, NULL);
    } else {
        clear_bit(HCI_RUNNING, &hdev->flags);
    }

    write_unlock_irqrestore(&data->lock, flags);

    return err;
}

static int bfusb_flush(struct hci_dev *hdev)
{
    struct bfusb_data *data = hci_get_drvdata(hdev);

    BT_DBG("hdev %p bfusb %p", hdev, data);

    skb_queue_purge(&data->transmit_q);

    return 0;
}

static int bfusb_close(struct hci_dev *hdev)
{
    struct bfusb_data *data = hci_get_drvdata(hdev);
    unsigned long flags;

    BT_DBG("hdev %p bfusb %p", hdev, data);

    if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
        return 0;

    write_lock_irqsave(&data->lock, flags);
    write_unlock_irqrestore(&data->lock, flags);

    bfusb_unlink_urbs(data);
    bfusb_flush(hdev);

    return 0;
}

static int bfusb_send_frame(struct sk_buff *skb)
{
    struct hci_dev *hdev = (struct hci_dev *) skb->dev;
    struct bfusb_data *data;
    struct sk_buff *nskb;
    unsigned char buf[3];
    int sent = 0, size, count;

    BT_DBG("hdev %p skb %p type %d len %d", hdev, skb, bt_cb(skb)->pkt_type, skb->len);

    if (!hdev) {
        BT_ERR("Frame for unknown HCI device (hdev=NULL)");
        return -ENODEV;
    }

    if (!test_bit(HCI_RUNNING, &hdev->flags))
        return -EBUSY;

    data = hci_get_drvdata(hdev);

    switch (bt_cb(skb)->pkt_type) {
    case HCI_COMMAND_PKT:
        hdev->stat.cmd_tx++;
        break;
    case HCI_ACLDATA_PKT:
        hdev->stat.acl_tx++;
        break;
    case HCI_SCODATA_PKT:
        hdev->stat.sco_tx++;
        break;
    };

    /* Prepend skb with frame type */
    memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);

    count = skb->len;

    /* Max HCI frame size seems to be 1511 + 1 */
    nskb = bt_skb_alloc(count + 32, GFP_ATOMIC);
    if (!nskb) {
        BT_ERR("Can't allocate memory for new packet");
        return -ENOMEM;
    }

    nskb->dev = (void *) data;

    while (count) {
        size = min_t(uint, count, BFUSB_MAX_BLOCK_SIZE);

        buf[0] = 0xc1 | ((sent == 0) ? 0x04 : 0) | ((count == size) ? 0x08 : 0);
        buf[1] = 0x00;
        buf[2] = (size == BFUSB_MAX_BLOCK_SIZE) ? 0 : size;

        memcpy(skb_put(nskb, 3), buf, 3);
        skb_copy_from_linear_data_offset(skb, sent, skb_put(nskb, size), size);

        sent  += size;
        count -= size;
    }

    /* Don't send frame with multiple size of bulk max packet */
    if ((nskb->len % data->bulk_pkt_size) == 0) {
        buf[0] = 0xdd;
        buf[1] = 0x00;
        memcpy(skb_put(nskb, 2), buf, 2);
    }

    read_lock(&data->lock);

    skb_queue_tail(&data->transmit_q, nskb);
    bfusb_tx_wakeup(data);

    read_unlock(&data->lock);

    kfree_skb(skb);

    return 0;
}

static int bfusb_ioctl(struct hci_dev *hdev, unsigned int cmd, unsigned long arg)
{
    return -ENOIOCTLCMD;
}

static int bfusb_load_firmware(struct bfusb_data *data,
                   const unsigned char *firmware, int count)
{
    unsigned char *buf;
    int err, pipe, len, size, sent = 0;

    BT_DBG("bfusb %p udev %p", data, data->udev);

    BT_INFO("BlueFRITZ! USB loading firmware");

    buf = kmalloc(BFUSB_MAX_BLOCK_SIZE + 3, GFP_KERNEL);
    if (!buf) {
        BT_ERR("Can't allocate memory chunk for firmware");
        return -ENOMEM;
    }

    pipe = usb_sndctrlpipe(data->udev, 0);

    if (usb_control_msg(data->udev, pipe, USB_REQ_SET_CONFIGURATION,
                0, 1, 0, NULL, 0, USB_CTRL_SET_TIMEOUT) < 0) {
        BT_ERR("Can't change to loading configuration");
        kfree(buf);
        return -EBUSY;
    }

    data->udev->toggle[0] = data->udev->toggle[1] = 0;

    pipe = usb_sndbulkpipe(data->udev, data->bulk_out_ep);

    while (count) {
        size = min_t(uint, count, BFUSB_MAX_BLOCK_SIZE + 3);

        memcpy(buf, firmware + sent, size);

        err = usb_bulk_msg(data->udev, pipe, buf, size,
                    &len, BFUSB_BLOCK_TIMEOUT);

        if (err || (len != size)) {
            BT_ERR("Error in firmware loading");
            goto error;
        }

        sent  += size;
        count -= size;
    }

    err = usb_bulk_msg(data->udev, pipe, NULL, 0,
                    &len, BFUSB_BLOCK_TIMEOUT);
    if (err < 0) {
        BT_ERR("Error in null packet request");
        goto error;
    }

    pipe = usb_sndctrlpipe(data->udev, 0);

    err = usb_control_msg(data->udev, pipe, USB_REQ_SET_CONFIGURATION,
                0, 2, 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
    if (err < 0) {
        BT_ERR("Can't change to running configuration");
        goto error;
    }

    data->udev->toggle[0] = data->udev->toggle[1] = 0;

    BT_INFO("BlueFRITZ! USB device ready");

    kfree(buf);
    return 0;

error:
    kfree(buf);

    pipe = usb_sndctrlpipe(data->udev, 0);

    usb_control_msg(data->udev, pipe, USB_REQ_SET_CONFIGURATION,
                0, 0, 0, NULL, 0, USB_CTRL_SET_TIMEOUT);

    return err;
}

static int bfusb_probe(struct usb_interface *intf, const struct usb_device_id *id)
{
    const struct firmware *firmware;
    struct usb_device *udev = interface_to_usbdev(intf);
    struct usb_host_endpoint *bulk_out_ep;
    struct usb_host_endpoint *bulk_in_ep;
    struct hci_dev *hdev;
    struct bfusb_data *data;

    BT_DBG("intf %p id %p", intf, id);

    /* Check number of endpoints */
    if (intf->cur_altsetting->desc.bNumEndpoints < 2)
        return -EIO;

    bulk_out_ep = &intf->cur_altsetting->endpoint[0];
    bulk_in_ep  = &intf->cur_altsetting->endpoint[1];

    if (!bulk_out_ep || !bulk_in_ep) {
        BT_ERR("Bulk endpoints not found");
        goto done;
    }

    /* Initialize control structure and load firmware */
    data = devm_kzalloc(&intf->dev, sizeof(struct bfusb_data), GFP_KERNEL);
    if (!data) {
        BT_ERR("Can't allocate memory for control structure");
        goto done;
    }

    data->udev = udev;
    data->bulk_in_ep    = bulk_in_ep->desc.bEndpointAddress;
    data->bulk_out_ep   = bulk_out_ep->desc.bEndpointAddress;
    data->bulk_pkt_size = le16_to_cpu(bulk_out_ep->desc.wMaxPacketSize);

    rwlock_init(&data->lock);

    data->reassembly = NULL;

    skb_queue_head_init(&data->transmit_q);
    skb_queue_head_init(&data->pending_q);
    skb_queue_head_init(&data->completed_q);

    if (request_firmware(&firmware, "bfubase.frm", &udev->dev) < 0) {
        BT_ERR("Firmware request failed");
        goto done;
    }

    BT_DBG("firmware data %p size %zu", firmware->data, firmware->size);

    if (bfusb_load_firmware(data, firmware->data, firmware->size) < 0) {
        BT_ERR("Firmware loading failed");
        goto release;
    }

    release_firmware(firmware);

    /* Initialize and register HCI device */
    hdev = hci_alloc_dev();
    if (!hdev) {
        BT_ERR("Can't allocate HCI device");
        goto done;
    }

    data->hdev = hdev;

    hdev->bus = HCI_USB;
    hci_set_drvdata(hdev, data);
    SET_HCIDEV_DEV(hdev, &intf->dev);

    hdev->open     = bfusb_open;
    hdev->close    = bfusb_close;
    hdev->flush    = bfusb_flush;
    hdev->send     = bfusb_send_frame;
    hdev->ioctl    = bfusb_ioctl;

    if (hci_register_dev(hdev) < 0) {
        BT_ERR("Can't register HCI device");
        hci_free_dev(hdev);
        goto done;
    }

    usb_set_intfdata(intf, data);

    return 0;

release:
    release_firmware(firmware);

done:
    return -EIO;
}

static void bfusb_disconnect(struct usb_interface *intf)
{
    struct bfusb_data *data = usb_get_intfdata(intf);
    struct hci_dev *hdev = data->hdev;

    BT_DBG("intf %p", intf);

    if (!hdev)
        return;

    usb_set_intfdata(intf, NULL);

    bfusb_close(hdev);

    hci_unregister_dev(hdev);
    hci_free_dev(hdev);
}

static struct usb_driver bfusb_driver = {
    .name       = "bfusb",
    .probe      = bfusb_probe,
    .disconnect = bfusb_disconnect,
    .id_table   = bfusb_table,
    .disable_hub_initiated_lpm = 1,
};

module_usb_driver(bfusb_driver);

MODULE_AUTHOR("Marcel Holtmann <[email protected]>");
MODULE_DESCRIPTION("BlueFRITZ! USB driver ver " VERSION);
MODULE_VERSION(VERSION);
MODULE_LICENSE("GPL");
MODULE_FIRMWARE("bfubase.frm");