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Release 4.16 drivers/usb/serial/aircable.c

// SPDX-License-Identifier: GPL-2.0
/*
 * AIRcable USB Bluetooth Dongle Driver.
 *
 * Copyright (C) 2010 Johan Hovold <jhovold@gmail.com>
 * Copyright (C) 2006 Manuel Francisco Naranjo (naranjo.manuel@gmail.com)
 *
 * The device works as an standard CDC device, it has 2 interfaces, the first
 * one is for firmware access and the second is the serial one.
 * The protocol is very simply, there are two possibilities reading or writing.
 * When writing the first urb must have a Header that starts with 0x20 0x29 the
 * next two bytes must say how much data will be sent.
 * When reading the process is almost equal except that the header starts with
 * 0x00 0x20.
 *
 * The device simply need some stuff to understand data coming from the usb
 * buffer: The First and Second byte is used for a Header, the Third and Fourth
 * tells the  device the amount of information the package holds.
 * Packages are 60 bytes long Header Stuff.
 * When writing to the device the first two bytes of the header are 0x20 0x29
 * When reading the bytes are 0x00 0x20, or 0x00 0x10, there is an strange
 * situation, when too much data arrives to the device because it sends the data
 * but with out the header. I will use a simply hack to override this situation,
 * if there is data coming that does not contain any header, then that is data
 * that must go directly to the tty, as there is no documentation about if there
 * is any other control code, I will simply check for the first
 * one.
 *
 * I have taken some info from a Greg Kroah-Hartman article:
 * http://www.linuxjournal.com/article/6573
 * And from Linux Device Driver Kit CD, which is a great work, the authors taken
 * the work to recompile lots of information an knowledge in drivers development
 * and made it all available inside a cd.
 * URL: http://kernel.org/pub/linux/kernel/people/gregkh/ddk/
 *
 */

#include <asm/unaligned.h>
#include <linux/tty.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/tty_flip.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>

/* Vendor and Product ID */

#define AIRCABLE_VID		0x16CA

#define AIRCABLE_USB_PID	0x1502

/* Protocol Stuff */

#define HCI_HEADER_LENGTH	0x4

#define TX_HEADER_0		0x20

#define TX_HEADER_1		0x29

#define RX_HEADER_0		0x00

#define RX_HEADER_1		0x20

#define HCI_COMPLETE_FRAME	64

/* rx_flags */

#define THROTTLED		0x01

#define ACTUALLY_THROTTLED	0x02


#define DRIVER_AUTHOR "Naranjo, Manuel Francisco <naranjo.manuel@gmail.com>, Johan Hovold <jhovold@gmail.com>"

#define DRIVER_DESC "AIRcable USB Driver"

/* ID table that will be registered with USB core */

static const struct usb_device_id id_table[] = {
	{ USB_DEVICE(AIRCABLE_VID, AIRCABLE_USB_PID) },
	{ },
};
MODULE_DEVICE_TABLE(usb, id_table);


static int aircable_prepare_write_buffer(struct usb_serial_port *port, void *dest, size_t size) { int count; unsigned char *buf = dest; count = kfifo_out_locked(&port->write_fifo, buf + HCI_HEADER_LENGTH, size - HCI_HEADER_LENGTH, &port->lock); buf[0] = TX_HEADER_0; buf[1] = TX_HEADER_1; put_unaligned_le16(count, &buf[2]); return count + HCI_HEADER_LENGTH; }

Contributors

PersonTokensPropCommitsCommitProp
Johan Hovold6985.19%360.00%
Manuel Francisco Naranjo89.88%120.00%
David Howells44.94%120.00%
Total81100.00%5100.00%


static int aircable_calc_num_ports(struct usb_serial *serial, struct usb_serial_endpoints *epds) { /* Ignore the first interface, which has no bulk endpoints. */ if (epds->num_bulk_out == 0) { dev_dbg(&serial->interface->dev, "ignoring interface with no bulk-out endpoints\n"); return -ENODEV; } return 1; }

Contributors

PersonTokensPropCommitsCommitProp
Johan Hovold1941.30%250.00%
Manuel Francisco Naranjo1941.30%125.00%
Greg Kroah-Hartman817.39%125.00%
Total46100.00%4100.00%


static int aircable_process_packet(struct usb_serial_port *port, int has_headers, char *packet, int len) { if (has_headers) { len -= HCI_HEADER_LENGTH; packet += HCI_HEADER_LENGTH; } if (len <= 0) { dev_dbg(&port->dev, "%s - malformed packet\n", __func__); return 0; } tty_insert_flip_string(&port->port, packet, len); return len; }

Contributors

PersonTokensPropCommitsCommitProp
Johan Hovold4561.64%120.00%
Manuel Francisco Naranjo1621.92%120.00%
Greg Kroah-Hartman79.59%120.00%
Jiri Slaby45.48%120.00%
Alan Cox11.37%120.00%
Total73100.00%5100.00%


static void aircable_process_read_urb(struct urb *urb) { struct usb_serial_port *port = urb->context; char *data = (char *)urb->transfer_buffer; int has_headers; int count; int len; int i; has_headers = (urb->actual_length > 2 && data[0] == RX_HEADER_0); count = 0; for (i = 0; i < urb->actual_length; i += HCI_COMPLETE_FRAME) { len = min_t(int, urb->actual_length - i, HCI_COMPLETE_FRAME); count += aircable_process_packet(port, has_headers, &data[i], len); } if (count) tty_flip_buffer_push(&port->port); }

Contributors

PersonTokensPropCommitsCommitProp
Johan Hovold8667.72%125.00%
Manuel Francisco Naranjo3124.41%125.00%
Alan Cox64.72%125.00%
Jiri Slaby43.15%125.00%
Total127100.00%4100.00%

static struct usb_serial_driver aircable_device = { .driver = { .owner = THIS_MODULE, .name = "aircable", }, .id_table = id_table, .bulk_out_size = HCI_COMPLETE_FRAME, .calc_num_ports = aircable_calc_num_ports, .process_read_urb = aircable_process_read_urb, .prepare_write_buffer = aircable_prepare_write_buffer, .throttle = usb_serial_generic_throttle, .unthrottle = usb_serial_generic_unthrottle, }; static struct usb_serial_driver * const serial_drivers[] = { &aircable_device, NULL }; module_usb_serial_driver(serial_drivers, id_table); MODULE_AUTHOR(DRIVER_AUTHOR); MODULE_DESCRIPTION(DRIVER_DESC); MODULE_LICENSE("GPL v2");

Overall Contributors

PersonTokensPropCommitsCommitProp
Johan Hovold23544.93%523.81%
Manuel Francisco Naranjo21641.30%14.76%
Greg Kroah-Hartman203.82%523.81%
Alan Stern163.06%14.76%
Johannes Hölzl112.10%14.76%
Jiri Slaby81.53%29.52%
Alan Cox71.34%29.52%
David Howells40.76%14.76%
Paul Gortmaker30.57%14.76%
Tejun Heo20.38%14.76%
Márton Németh10.19%14.76%
Total523100.00%21100.00%
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