IRQ: Maintain regs pointer globally rather than passing to IRQ handlers

[mirror_ubuntu-focal-kernel.git] / drivers / bluetooth / bfusb.c

/*
 *
 *  AVM BlueFRITZ! USB driver
 *
 *  Copyright (C) 2003-2006  Marcel Holtmann <marcel@holtmann.org>
 *
 *
 *  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/sched.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>

#ifndef CONFIG_BT_HCIBFUSB_DEBUG
#undef  BT_DBG
#define BT_DBG(D...)
#endif

#define VERSION "1.1"

static int ignore = 0;

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", bfusb, 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);
                if (data->reassembly)
                        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", bfusb, 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 = hdev->driver_data;
        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 = hdev->driver_data;

        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 = hdev->driver_data;
        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 = hdev->driver_data;

        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);
                memcpy(skb_put(nskb, size), skb->data + sent, 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 void bfusb_destruct(struct hci_dev *hdev)
{
        struct bfusb_data *data = hdev->driver_data;

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

        kfree(data);
}

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, 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");

        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");
                return -EBUSY;
        }

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

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

        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);

        if (ignore)
                return -ENODEV;

        /* 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 = kzalloc(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 error;
        }

        BT_DBG("firmware data %p size %d", 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 error;
        }

        data->hdev = hdev;

        hdev->type = HCI_USB;
        hdev->driver_data = 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->destruct = bfusb_destruct;
        hdev->ioctl    = bfusb_ioctl;

        hdev->owner = THIS_MODULE;

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

        usb_set_intfdata(intf, data);

        return 0;

release:
        release_firmware(firmware);

error:
        kfree(data);

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);

        if (hci_unregister_dev(hdev) < 0)
                BT_ERR("Can't unregister HCI device %s", hdev->name);

        hci_free_dev(hdev);
}

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

static int __init bfusb_init(void)
{
        int err;

        BT_INFO("BlueFRITZ! USB driver ver %s", VERSION);

        err = usb_register(&bfusb_driver);
        if (err < 0)
                BT_ERR("Failed to register BlueFRITZ! USB driver");

        return err;
}

static void __exit bfusb_exit(void)
{
        usb_deregister(&bfusb_driver);
}

module_init(bfusb_init);
module_exit(bfusb_exit);

module_param(ignore, bool, 0644);
MODULE_PARM_DESC(ignore, "Ignore devices from the matching table");

MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
MODULE_DESCRIPTION("BlueFRITZ! USB driver ver " VERSION);
MODULE_VERSION(VERSION);
MODULE_LICENSE("GPL");