Add linux-next specific files for 20110831
[linux-2.6/next.git] / drivers / usb / serial / aircable.c
blobb43d07df4c44ac3c38d0b31997389669a6943613
1 /*
2 * AIRcable USB Bluetooth Dongle Driver.
4 * Copyright (C) 2010 Johan Hovold <jhovold@gmail.com>
5 * Copyright (C) 2006 Manuel Francisco Naranjo (naranjo.manuel@gmail.com)
7 * This program is free software; you can redistribute it and/or modify it under
8 * the terms of the GNU General Public License version 2 as published by the
9 * Free Software Foundation.
11 * The device works as an standard CDC device, it has 2 interfaces, the first
12 * one is for firmware access and the second is the serial one.
13 * The protocol is very simply, there are two posibilities reading or writing.
14 * When writing the first urb must have a Header that starts with 0x20 0x29 the
15 * next two bytes must say how much data will be sended.
16 * When reading the process is almost equal except that the header starts with
17 * 0x00 0x20.
19 * The device simply need some stuff to understand data coming from the usb
20 * buffer: The First and Second byte is used for a Header, the Third and Fourth
21 * tells the device the amount of information the package holds.
22 * Packages are 60 bytes long Header Stuff.
23 * When writing to the device the first two bytes of the header are 0x20 0x29
24 * When reading the bytes are 0x00 0x20, or 0x00 0x10, there is an strange
25 * situation, when too much data arrives to the device because it sends the data
26 * but with out the header. I will use a simply hack to override this situation,
27 * if there is data coming that does not contain any header, then that is data
28 * that must go directly to the tty, as there is no documentation about if there
29 * is any other control code, I will simply check for the first
30 * one.
32 * The driver registers himself with the USB-serial core and the USB Core. I had
33 * to implement a probe function against USB-serial, because other way, the
34 * driver was attaching himself to both interfaces. I have tryed with different
35 * configurations of usb_serial_driver with out exit, only the probe function
36 * could handle this correctly.
38 * I have taken some info from a Greg Kroah-Hartman article:
39 * http://www.linuxjournal.com/article/6573
40 * And from Linux Device Driver Kit CD, which is a great work, the authors taken
41 * the work to recompile lots of information an knowladge in drivers development
42 * and made it all avaible inside a cd.
43 * URL: http://kernel.org/pub/linux/kernel/people/gregkh/ddk/
47 #include <asm/unaligned.h>
48 #include <linux/tty.h>
49 #include <linux/slab.h>
50 #include <linux/module.h>
51 #include <linux/tty_flip.h>
52 #include <linux/usb.h>
53 #include <linux/usb/serial.h>
55 static int debug;
57 /* Vendor and Product ID */
58 #define AIRCABLE_VID 0x16CA
59 #define AIRCABLE_USB_PID 0x1502
61 /* Protocol Stuff */
62 #define HCI_HEADER_LENGTH 0x4
63 #define TX_HEADER_0 0x20
64 #define TX_HEADER_1 0x29
65 #define RX_HEADER_0 0x00
66 #define RX_HEADER_1 0x20
67 #define HCI_COMPLETE_FRAME 64
69 /* rx_flags */
70 #define THROTTLED 0x01
71 #define ACTUALLY_THROTTLED 0x02
74 * Version Information
76 #define DRIVER_VERSION "v2.0"
77 #define DRIVER_AUTHOR "Naranjo, Manuel Francisco <naranjo.manuel@gmail.com>, Johan Hovold <jhovold@gmail.com>"
78 #define DRIVER_DESC "AIRcable USB Driver"
80 /* ID table that will be registered with USB core */
81 static const struct usb_device_id id_table[] = {
82 { USB_DEVICE(AIRCABLE_VID, AIRCABLE_USB_PID) },
83 { },
85 MODULE_DEVICE_TABLE(usb, id_table);
87 static int aircable_prepare_write_buffer(struct usb_serial_port *port,
88 void *dest, size_t size)
90 int count;
91 unsigned char *buf = dest;
93 count = kfifo_out_locked(&port->write_fifo, buf + HCI_HEADER_LENGTH,
94 size - HCI_HEADER_LENGTH, &port->lock);
95 buf[0] = TX_HEADER_0;
96 buf[1] = TX_HEADER_1;
97 put_unaligned_le16(count, &buf[2]);
99 return count + HCI_HEADER_LENGTH;
102 static int aircable_probe(struct usb_serial *serial,
103 const struct usb_device_id *id)
105 struct usb_host_interface *iface_desc = serial->interface->
106 cur_altsetting;
107 struct usb_endpoint_descriptor *endpoint;
108 int num_bulk_out = 0;
109 int i;
111 for (i = 0; i < iface_desc->desc.bNumEndpoints; i++) {
112 endpoint = &iface_desc->endpoint[i].desc;
113 if (usb_endpoint_is_bulk_out(endpoint)) {
114 dbg("found bulk out on endpoint %d", i);
115 ++num_bulk_out;
119 if (num_bulk_out == 0) {
120 dbg("Invalid interface, discarding");
121 return -ENODEV;
124 return 0;
127 static int aircable_process_packet(struct tty_struct *tty,
128 struct usb_serial_port *port, int has_headers,
129 char *packet, int len)
131 if (has_headers) {
132 len -= HCI_HEADER_LENGTH;
133 packet += HCI_HEADER_LENGTH;
135 if (len <= 0) {
136 dbg("%s - malformed packet", __func__);
137 return 0;
140 tty_insert_flip_string(tty, packet, len);
142 return len;
145 static void aircable_process_read_urb(struct urb *urb)
147 struct usb_serial_port *port = urb->context;
148 char *data = (char *)urb->transfer_buffer;
149 struct tty_struct *tty;
150 int has_headers;
151 int count;
152 int len;
153 int i;
155 tty = tty_port_tty_get(&port->port);
156 if (!tty)
157 return;
159 has_headers = (urb->actual_length > 2 && data[0] == RX_HEADER_0);
161 count = 0;
162 for (i = 0; i < urb->actual_length; i += HCI_COMPLETE_FRAME) {
163 len = min_t(int, urb->actual_length - i, HCI_COMPLETE_FRAME);
164 count += aircable_process_packet(tty, port, has_headers,
165 &data[i], len);
168 if (count)
169 tty_flip_buffer_push(tty);
170 tty_kref_put(tty);
173 static struct usb_driver aircable_driver = {
174 .name = "aircable",
175 .probe = usb_serial_probe,
176 .disconnect = usb_serial_disconnect,
177 .id_table = id_table,
178 .no_dynamic_id = 1,
181 static struct usb_serial_driver aircable_device = {
182 .driver = {
183 .owner = THIS_MODULE,
184 .name = "aircable",
186 .usb_driver = &aircable_driver,
187 .id_table = id_table,
188 .num_ports = 1,
189 .bulk_out_size = HCI_COMPLETE_FRAME,
190 .probe = aircable_probe,
191 .process_read_urb = aircable_process_read_urb,
192 .prepare_write_buffer = aircable_prepare_write_buffer,
193 .throttle = usb_serial_generic_throttle,
194 .unthrottle = usb_serial_generic_unthrottle,
197 static int __init aircable_init(void)
199 int retval;
200 retval = usb_serial_register(&aircable_device);
201 if (retval)
202 goto failed_serial_register;
203 retval = usb_register(&aircable_driver);
204 if (retval)
205 goto failed_usb_register;
206 return 0;
208 failed_usb_register:
209 usb_serial_deregister(&aircable_device);
210 failed_serial_register:
211 return retval;
214 static void __exit aircable_exit(void)
216 usb_deregister(&aircable_driver);
217 usb_serial_deregister(&aircable_device);
220 MODULE_AUTHOR(DRIVER_AUTHOR);
221 MODULE_DESCRIPTION(DRIVER_DESC);
222 MODULE_VERSION(DRIVER_VERSION);
223 MODULE_LICENSE("GPL");
225 module_init(aircable_init);
226 module_exit(aircable_exit);
228 module_param(debug, bool, S_IRUGO | S_IWUSR);
229 MODULE_PARM_DESC(debug, "Debug enabled or not");