// 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/atomic.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");