root/drivers/bluetooth/bcm203x.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *
 *  Broadcom Blutonium firmware driver
 *
 *  Copyright (C) 2003  Maxim Krasnyansky <maxk@qualcomm.com>
 *  Copyright (C) 2003  Marcel Holtmann <marcel@holtmann.org>
 */

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

#include <linux/usb.h>

#include <net/bluetooth/bluetooth.h>

#define VERSION "1.2"

static const struct usb_device_id bcm203x_table[] = {
        /* Broadcom Blutonium (BCM2033) */
        { USB_DEVICE(0x0a5c, 0x2033) },

        { }     /* Terminating entry */
};

MODULE_DEVICE_TABLE(usb, bcm203x_table);

#define BCM203X_ERROR           0
#define BCM203X_RESET           1
#define BCM203X_LOAD_MINIDRV    2
#define BCM203X_SELECT_MEMORY   3
#define BCM203X_CHECK_MEMORY    4
#define BCM203X_LOAD_FIRMWARE   5
#define BCM203X_CHECK_FIRMWARE  6

#define BCM203X_IN_EP           0x81
#define BCM203X_OUT_EP          0x02

struct bcm203x_data {
        struct usb_device       *udev;

        unsigned long           state;

        struct work_struct      work;
        atomic_t                shutdown;

        struct urb              *urb;
        unsigned char           *buffer;

        unsigned char           *fw_data;
        unsigned int            fw_size;
        unsigned int            fw_sent;
};

static void bcm203x_complete(struct urb *urb)
{
        struct bcm203x_data *data = urb->context;
        struct usb_device *udev = urb->dev;
        int len;

        BT_DBG("udev %p urb %p", udev, urb);

        if (urb->status) {
                BT_ERR("URB failed with status %d", urb->status);
                data->state = BCM203X_ERROR;
                return;
        }

        switch (data->state) {
        case BCM203X_LOAD_MINIDRV:
                memcpy(data->buffer, "#", 1);

                usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, BCM203X_OUT_EP),
                                data->buffer, 1, bcm203x_complete, data);

                data->state = BCM203X_SELECT_MEMORY;

                /* use workqueue to have a small delay */
                schedule_work(&data->work);
                break;

        case BCM203X_SELECT_MEMORY:
                usb_fill_int_urb(urb, udev, usb_rcvintpipe(udev, BCM203X_IN_EP),
                                data->buffer, 32, bcm203x_complete, data, 1);

                data->state = BCM203X_CHECK_MEMORY;

                if (usb_submit_urb(data->urb, GFP_ATOMIC) < 0)
                        BT_ERR("Can't submit URB");
                break;

        case BCM203X_CHECK_MEMORY:
                if (data->buffer[0] != '#') {
                        BT_ERR("Memory select failed");
                        data->state = BCM203X_ERROR;
                        break;
                }

                data->state = BCM203X_LOAD_FIRMWARE;
                fallthrough;
        case BCM203X_LOAD_FIRMWARE:
                if (data->fw_sent == data->fw_size) {
                        usb_fill_int_urb(urb, udev, usb_rcvintpipe(udev, BCM203X_IN_EP),
                                data->buffer, 32, bcm203x_complete, data, 1);

                        data->state = BCM203X_CHECK_FIRMWARE;
                } else {
                        len = min_t(uint, data->fw_size - data->fw_sent, 4096);

                        usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, BCM203X_OUT_EP),
                                data->fw_data + data->fw_sent, len, bcm203x_complete, data);

                        data->fw_sent += len;
                }

                if (usb_submit_urb(data->urb, GFP_ATOMIC) < 0)
                        BT_ERR("Can't submit URB");
                break;

        case BCM203X_CHECK_FIRMWARE:
                if (data->buffer[0] != '.') {
                        BT_ERR("Firmware loading failed");
                        data->state = BCM203X_ERROR;
                        break;
                }

                data->state = BCM203X_RESET;
                break;
        }
}

static void bcm203x_work(struct work_struct *work)
{
        struct bcm203x_data *data =
                container_of(work, struct bcm203x_data, work);

        if (atomic_read(&data->shutdown))
                return;

        if (usb_submit_urb(data->urb, GFP_KERNEL) < 0)
                BT_ERR("Can't submit URB");
}

static int bcm203x_probe(struct usb_interface *intf, const struct usb_device_id *id)
{
        const struct firmware *firmware;
        struct usb_device *udev = interface_to_usbdev(intf);
        struct bcm203x_data *data;
        int size;

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

        if (intf->cur_altsetting->desc.bInterfaceNumber != 0)
                return -ENODEV;

        data = devm_kzalloc(&intf->dev, sizeof(*data), GFP_KERNEL);
        if (!data)
                return -ENOMEM;

        data->udev  = udev;
        data->state = BCM203X_LOAD_MINIDRV;

        data->urb = usb_alloc_urb(0, GFP_KERNEL);
        if (!data->urb)
                return -ENOMEM;

        if (request_firmware(&firmware, "BCM2033-MD.hex", &udev->dev) < 0) {
                BT_ERR("Mini driver request failed");
                usb_free_urb(data->urb);
                return -EIO;
        }

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

        size = max_t(uint, firmware->size, 4096);

        data->buffer = kmalloc(size, GFP_KERNEL);
        if (!data->buffer) {
                BT_ERR("Can't allocate memory for mini driver");
                release_firmware(firmware);
                usb_free_urb(data->urb);
                return -ENOMEM;
        }

        memcpy(data->buffer, firmware->data, firmware->size);

        usb_fill_bulk_urb(data->urb, udev, usb_sndbulkpipe(udev, BCM203X_OUT_EP),
                        data->buffer, firmware->size, bcm203x_complete, data);

        release_firmware(firmware);

        if (request_firmware(&firmware, "BCM2033-FW.bin", &udev->dev) < 0) {
                BT_ERR("Firmware request failed");
                usb_free_urb(data->urb);
                kfree(data->buffer);
                return -EIO;
        }

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

        data->fw_data = kmemdup(firmware->data, firmware->size, GFP_KERNEL);
        if (!data->fw_data) {
                BT_ERR("Can't allocate memory for firmware image");
                release_firmware(firmware);
                usb_free_urb(data->urb);
                kfree(data->buffer);
                return -ENOMEM;
        }

        data->fw_size = firmware->size;
        data->fw_sent = 0;

        release_firmware(firmware);

        INIT_WORK(&data->work, bcm203x_work);

        usb_set_intfdata(intf, data);

        /* use workqueue to have a small delay */
        schedule_work(&data->work);

        return 0;
}

static void bcm203x_disconnect(struct usb_interface *intf)
{
        struct bcm203x_data *data = usb_get_intfdata(intf);

        BT_DBG("intf %p", intf);

        atomic_inc(&data->shutdown);
        cancel_work_sync(&data->work);

        usb_kill_urb(data->urb);

        usb_set_intfdata(intf, NULL);

        usb_free_urb(data->urb);
        kfree(data->fw_data);
        kfree(data->buffer);
}

static struct usb_driver bcm203x_driver = {
        .name           = "bcm203x",
        .probe          = bcm203x_probe,
        .disconnect     = bcm203x_disconnect,
        .id_table       = bcm203x_table,
        .disable_hub_initiated_lpm = 1,
};

module_usb_driver(bcm203x_driver);

MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
MODULE_DESCRIPTION("Broadcom Blutonium firmware driver ver " VERSION);
MODULE_VERSION(VERSION);
MODULE_LICENSE("GPL");
MODULE_FIRMWARE("BCM2033-MD.hex");
MODULE_FIRMWARE("BCM2033-FW.bin");