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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Safe Encapsulated USB Serial Driver
3 *
Johan Hovold241c80e2010-05-19 00:01:30 +02004 * Copyright (C) 2010 Johan Hovold <jhovold@gmail.com>
Linus Torvalds1da177e2005-04-16 15:20:36 -07005 * Copyright (C) 2001 Lineo
6 * Copyright (C) 2001 Hewlett-Packard
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * By:
14 * Stuart Lynne <sl@lineo.com>, Tom Rushworth <tbr@lineo.com>
15 */
16
Alan Cox43c8f432008-07-22 11:15:26 +010017/*
18 * The encapsultaion is designed to overcome difficulties with some USB
19 * hardware.
Linus Torvalds1da177e2005-04-16 15:20:36 -070020 *
21 * While the USB protocol has a CRC over the data while in transit, i.e. while
Alan Cox43c8f432008-07-22 11:15:26 +010022 * being carried over the bus, there is no end to end protection. If the
23 * hardware has any problems getting the data into or out of the USB transmit
24 * and receive FIFO's then data can be lost.
Linus Torvalds1da177e2005-04-16 15:20:36 -070025 *
Alan Cox43c8f432008-07-22 11:15:26 +010026 * This protocol adds a two byte trailer to each USB packet to specify the
27 * number of bytes of valid data and a 10 bit CRC that will allow the receiver
28 * to verify that the entire USB packet was received without error.
Linus Torvalds1da177e2005-04-16 15:20:36 -070029 *
Alan Cox43c8f432008-07-22 11:15:26 +010030 * Because in this case the sender and receiver are the class and function
31 * drivers there is now end to end protection.
Linus Torvalds1da177e2005-04-16 15:20:36 -070032 *
Alan Cox43c8f432008-07-22 11:15:26 +010033 * There is an additional option that can be used to force all transmitted
34 * packets to be padded to the maximum packet size. This provides a work
35 * around for some devices which have problems with small USB packets.
Linus Torvalds1da177e2005-04-16 15:20:36 -070036 *
37 * Assuming a packetsize of N:
38 *
39 * 0..N-2 data and optional padding
40 *
41 * N-2 bits 7-2 - number of bytes of valid data
42 * bits 1-0 top two bits of 10 bit CRC
43 * N-1 bottom 8 bits of 10 bit CRC
44 *
45 *
46 * | Data Length | 10 bit CRC |
47 * + 7 . 6 . 5 . 4 . 3 . 2 . 1 . 0 | 7 . 6 . 5 . 4 . 3 . 2 . 1 . 0 +
48 *
Alan Cox43c8f432008-07-22 11:15:26 +010049 * The 10 bit CRC is computed across the sent data, followed by the trailer
50 * with the length set and the CRC set to zero. The CRC is then OR'd into
51 * the trailer.
Linus Torvalds1da177e2005-04-16 15:20:36 -070052 *
Alan Cox43c8f432008-07-22 11:15:26 +010053 * When received a 10 bit CRC is computed over the entire frame including
54 * the trailer and should be equal to zero.
Linus Torvalds1da177e2005-04-16 15:20:36 -070055 *
56 * Two module parameters are used to control the encapsulation, if both are
57 * turned of the module works as a simple serial device with NO
58 * encapsulation.
59 *
60 * See linux/drivers/usbd/serial_fd for a device function driver
61 * implementation of this.
62 *
63 */
64
65
Linus Torvalds1da177e2005-04-16 15:20:36 -070066#include <linux/kernel.h>
67#include <linux/errno.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090068#include <linux/gfp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070069#include <linux/init.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070070#include <linux/tty.h>
71#include <linux/tty_driver.h>
72#include <linux/tty_flip.h>
73#include <linux/module.h>
74#include <linux/spinlock.h>
Alan Cox43c8f432008-07-22 11:15:26 +010075#include <linux/uaccess.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070076#include <linux/usb.h>
Greg Kroah-Hartmana9698882006-07-11 21:22:58 -070077#include <linux/usb/serial.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070078
79
Robert P. J. Day3aec6e22007-07-30 06:38:31 -040080#ifndef CONFIG_USB_SERIAL_SAFE_PADDED
81#define CONFIG_USB_SERIAL_SAFE_PADDED 0
Linus Torvalds1da177e2005-04-16 15:20:36 -070082#endif
83
84static int debug;
85static int safe = 1;
Robert P. J. Day3aec6e22007-07-30 06:38:31 -040086static int padded = CONFIG_USB_SERIAL_SAFE_PADDED;
Linus Torvalds1da177e2005-04-16 15:20:36 -070087
Johan Hovold241c80e2010-05-19 00:01:30 +020088#define DRIVER_VERSION "v0.1"
89#define DRIVER_AUTHOR "sl@lineo.com, tbr@lineo.com, Johan Hovold <jhovold@gmail.com>"
Linus Torvalds1da177e2005-04-16 15:20:36 -070090#define DRIVER_DESC "USB Safe Encapsulated Serial"
91
Alan Cox43c8f432008-07-22 11:15:26 +010092MODULE_AUTHOR(DRIVER_AUTHOR);
93MODULE_DESCRIPTION(DRIVER_DESC);
Linus Torvalds1da177e2005-04-16 15:20:36 -070094MODULE_LICENSE("GPL");
95
Alan Cox43c8f432008-07-22 11:15:26 +010096static __u16 vendor; /* no default */
97static __u16 product; /* no default */
Linus Torvalds1da177e2005-04-16 15:20:36 -070098module_param(vendor, ushort, 0);
99MODULE_PARM_DESC(vendor, "User specified USB idVendor (required)");
100module_param(product, ushort, 0);
101MODULE_PARM_DESC(product, "User specified USB idProduct (required)");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102
103module_param(debug, bool, S_IRUGO | S_IWUSR);
104MODULE_PARM_DESC(debug, "Debug enabled or not");
105
106module_param(safe, bool, 0);
107MODULE_PARM_DESC(safe, "Turn Safe Encapsulation On/Off");
108
109module_param(padded, bool, 0);
110MODULE_PARM_DESC(padded, "Pad to full wMaxPacketSize On/Off");
111
112#define CDC_DEVICE_CLASS 0x02
113
114#define CDC_INTERFACE_CLASS 0x02
115#define CDC_INTERFACE_SUBCLASS 0x06
116
117#define LINEO_INTERFACE_CLASS 0xff
118
119#define LINEO_INTERFACE_SUBCLASS_SAFENET 0x01
120#define LINEO_SAFENET_CRC 0x01
121#define LINEO_SAFENET_CRC_PADDED 0x02
122
123#define LINEO_INTERFACE_SUBCLASS_SAFESERIAL 0x02
124#define LINEO_SAFESERIAL_CRC 0x01
125#define LINEO_SAFESERIAL_CRC_PADDED 0x02
126
127
Alan Cox43c8f432008-07-22 11:15:26 +0100128#define MY_USB_DEVICE(vend, prod, dc, ic, isc) \
129 .match_flags = USB_DEVICE_ID_MATCH_DEVICE | \
130 USB_DEVICE_ID_MATCH_DEV_CLASS | \
131 USB_DEVICE_ID_MATCH_INT_CLASS | \
132 USB_DEVICE_ID_MATCH_INT_SUBCLASS, \
133 .idVendor = (vend), \
134 .idProduct = (prod),\
135 .bDeviceClass = (dc),\
136 .bInterfaceClass = (ic), \
137 .bInterfaceSubClass = (isc),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700138
139static struct usb_device_id id_table[] = {
Alan Cox43c8f432008-07-22 11:15:26 +0100140 {MY_USB_DEVICE(0x49f, 0xffff, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, /* Itsy */
141 {MY_USB_DEVICE(0x3f0, 0x2101, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, /* Calypso */
142 {MY_USB_DEVICE(0x4dd, 0x8001, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, /* Iris */
143 {MY_USB_DEVICE(0x4dd, 0x8002, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, /* Collie */
144 {MY_USB_DEVICE(0x4dd, 0x8003, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, /* Collie */
145 {MY_USB_DEVICE(0x4dd, 0x8004, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, /* Collie */
146 {MY_USB_DEVICE(0x5f9, 0xffff, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, /* Sharp tmp */
147 /* extra null entry for module vendor/produc parameters */
148 {MY_USB_DEVICE(0, 0, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)},
149 {} /* terminating entry */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150};
151
Alan Cox43c8f432008-07-22 11:15:26 +0100152MODULE_DEVICE_TABLE(usb, id_table);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153
154static struct usb_driver safe_driver = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155 .name = "safe_serial",
156 .probe = usb_serial_probe,
157 .disconnect = usb_serial_disconnect,
158 .id_table = id_table,
Greg Kroah-Hartmanba9dc652005-11-16 13:41:28 -0800159 .no_dynamic_id = 1,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160};
161
Arjan van de Ven4c4c9432005-11-29 09:43:42 +0100162static const __u16 crc10_table[256] = {
Alan Cox43c8f432008-07-22 11:15:26 +0100163 0x000, 0x233, 0x255, 0x066, 0x299, 0x0aa, 0x0cc, 0x2ff,
164 0x301, 0x132, 0x154, 0x367, 0x198, 0x3ab, 0x3cd, 0x1fe,
165 0x031, 0x202, 0x264, 0x057, 0x2a8, 0x09b, 0x0fd, 0x2ce,
166 0x330, 0x103, 0x165, 0x356, 0x1a9, 0x39a, 0x3fc, 0x1cf,
167 0x062, 0x251, 0x237, 0x004, 0x2fb, 0x0c8, 0x0ae, 0x29d,
168 0x363, 0x150, 0x136, 0x305, 0x1fa, 0x3c9, 0x3af, 0x19c,
169 0x053, 0x260, 0x206, 0x035, 0x2ca, 0x0f9, 0x09f, 0x2ac,
170 0x352, 0x161, 0x107, 0x334, 0x1cb, 0x3f8, 0x39e, 0x1ad,
171 0x0c4, 0x2f7, 0x291, 0x0a2, 0x25d, 0x06e, 0x008, 0x23b,
172 0x3c5, 0x1f6, 0x190, 0x3a3, 0x15c, 0x36f, 0x309, 0x13a,
173 0x0f5, 0x2c6, 0x2a0, 0x093, 0x26c, 0x05f, 0x039, 0x20a,
174 0x3f4, 0x1c7, 0x1a1, 0x392, 0x16d, 0x35e, 0x338, 0x10b,
175 0x0a6, 0x295, 0x2f3, 0x0c0, 0x23f, 0x00c, 0x06a, 0x259,
176 0x3a7, 0x194, 0x1f2, 0x3c1, 0x13e, 0x30d, 0x36b, 0x158,
177 0x097, 0x2a4, 0x2c2, 0x0f1, 0x20e, 0x03d, 0x05b, 0x268,
178 0x396, 0x1a5, 0x1c3, 0x3f0, 0x10f, 0x33c, 0x35a, 0x169,
179 0x188, 0x3bb, 0x3dd, 0x1ee, 0x311, 0x122, 0x144, 0x377,
180 0x289, 0x0ba, 0x0dc, 0x2ef, 0x010, 0x223, 0x245, 0x076,
181 0x1b9, 0x38a, 0x3ec, 0x1df, 0x320, 0x113, 0x175, 0x346,
182 0x2b8, 0x08b, 0x0ed, 0x2de, 0x021, 0x212, 0x274, 0x047,
183 0x1ea, 0x3d9, 0x3bf, 0x18c, 0x373, 0x140, 0x126, 0x315,
184 0x2eb, 0x0d8, 0x0be, 0x28d, 0x072, 0x241, 0x227, 0x014,
185 0x1db, 0x3e8, 0x38e, 0x1bd, 0x342, 0x171, 0x117, 0x324,
186 0x2da, 0x0e9, 0x08f, 0x2bc, 0x043, 0x270, 0x216, 0x025,
187 0x14c, 0x37f, 0x319, 0x12a, 0x3d5, 0x1e6, 0x180, 0x3b3,
188 0x24d, 0x07e, 0x018, 0x22b, 0x0d4, 0x2e7, 0x281, 0x0b2,
189 0x17d, 0x34e, 0x328, 0x11b, 0x3e4, 0x1d7, 0x1b1, 0x382,
190 0x27c, 0x04f, 0x029, 0x21a, 0x0e5, 0x2d6, 0x2b0, 0x083,
191 0x12e, 0x31d, 0x37b, 0x148, 0x3b7, 0x184, 0x1e2, 0x3d1,
192 0x22f, 0x01c, 0x07a, 0x249, 0x0b6, 0x285, 0x2e3, 0x0d0,
193 0x11f, 0x32c, 0x34a, 0x179, 0x386, 0x1b5, 0x1d3, 0x3e0,
194 0x21e, 0x02d, 0x04b, 0x278, 0x087, 0x2b4, 0x2d2, 0x0e1,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700195};
196
Alan Cox43c8f432008-07-22 11:15:26 +0100197#define CRC10_INITFCS 0x000 /* Initial FCS value */
198#define CRC10_GOODFCS 0x000 /* Good final FCS value */
199#define CRC10_FCS(fcs, c) ((((fcs) << 8) & 0x3ff) ^ crc10_table[((fcs) >> 2) & 0xff] ^ (c))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200
Alan Cox43c8f432008-07-22 11:15:26 +0100201/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202 * fcs_compute10 - memcpy and calculate 10 bit CRC across buffer
203 * @sp: pointer to buffer
204 * @len: number of bytes
205 * @fcs: starting FCS
206 *
207 * Perform a memcpy and calculate fcs using ppp 10bit CRC algorithm. Return
208 * new 10 bit FCS.
209 */
Alan Cox43c8f432008-07-22 11:15:26 +0100210static __u16 __inline__ fcs_compute10(unsigned char *sp, int len, __u16 fcs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211{
Alan Cox43c8f432008-07-22 11:15:26 +0100212 for (; len-- > 0; fcs = CRC10_FCS(fcs, *sp++));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213 return fcs;
214}
215
Johan Hovold12e2e522010-05-19 00:01:31 +0200216static void safe_process_read_urb(struct urb *urb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217{
Johan Hovold12e2e522010-05-19 00:01:31 +0200218 struct usb_serial_port *port = urb->context;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219 unsigned char *data = urb->transfer_buffer;
220 unsigned char length = urb->actual_length;
Johan Hovold6d1bf482010-05-19 00:01:32 +0200221 int actual_length;
Alan Cox4a90f092008-10-13 10:39:46 +0100222 struct tty_struct *tty;
Johan Hovold6d1bf482010-05-19 00:01:32 +0200223 __u16 fcs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224
Johan Hovold12e2e522010-05-19 00:01:31 +0200225 if (!length)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227
Alan Cox4a90f092008-10-13 10:39:46 +0100228 tty = tty_port_tty_get(&port->port);
Johan Hovold12e2e522010-05-19 00:01:31 +0200229 if (!tty)
230 return;
231
Johan Hovold6d1bf482010-05-19 00:01:32 +0200232 if (!safe)
233 goto out;
234
235 fcs = fcs_compute10(data, length, CRC10_INITFCS);
236 if (fcs) {
237 dev_err(&port->dev, "%s - bad CRC %x\n", __func__, fcs);
238 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 }
Johan Hovold12e2e522010-05-19 00:01:31 +0200240
Johan Hovold6d1bf482010-05-19 00:01:32 +0200241 actual_length = data[length - 2] >> 2;
242 if (actual_length > (length - 2)) {
243 dev_err(&port->dev, "%s - inconsistent lengths %d:%d\n",
244 __func__, actual_length, length);
245 goto err;
246 }
247 dev_info(&urb->dev->dev, "%s - actual: %d\n", __func__, actual_length);
248 length = actual_length;
249out:
250 tty_insert_flip_string(tty, data, length);
251 tty_flip_buffer_push(tty);
252err:
Alan Cox4a90f092008-10-13 10:39:46 +0100253 tty_kref_put(tty);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254}
255
Johan Hovold241c80e2010-05-19 00:01:30 +0200256static int safe_prepare_write_buffer(struct usb_serial_port *port,
257 void *dest, size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258{
Johan Hovold241c80e2010-05-19 00:01:30 +0200259 unsigned char *buf = dest;
260 int count;
261 int trailer_len;
262 int pkt_len;
263 __u16 fcs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700264
Johan Hovold241c80e2010-05-19 00:01:30 +0200265 trailer_len = safe ? 2 : 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266
Johan Hovold241c80e2010-05-19 00:01:30 +0200267 count = kfifo_out_locked(&port->write_fifo, buf, size - trailer_len,
268 &port->lock);
269 if (!safe)
270 return count;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271
Johan Hovold241c80e2010-05-19 00:01:30 +0200272 /* pad if necessary */
273 if (padded) {
274 pkt_len = size;
275 memset(buf + count, '0', pkt_len - count - trailer_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276 } else {
Johan Hovold241c80e2010-05-19 00:01:30 +0200277 pkt_len = count + trailer_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278 }
279
Johan Hovold241c80e2010-05-19 00:01:30 +0200280 /* set count */
281 buf[pkt_len - 2] = count << 2;
282 buf[pkt_len - 1] = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283
Johan Hovold241c80e2010-05-19 00:01:30 +0200284 /* compute fcs and insert into trailer */
285 fcs = fcs_compute10(buf, pkt_len, CRC10_INITFCS);
286 buf[pkt_len - 2] |= fcs >> 8;
287 buf[pkt_len - 1] |= fcs & 0xff;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288
Johan Hovold241c80e2010-05-19 00:01:30 +0200289 return pkt_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290}
291
Alan Cox43c8f432008-07-22 11:15:26 +0100292static int safe_startup(struct usb_serial *serial)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293{
294 switch (serial->interface->cur_altsetting->desc.bInterfaceProtocol) {
295 case LINEO_SAFESERIAL_CRC:
296 break;
297 case LINEO_SAFESERIAL_CRC_PADDED:
298 padded = 1;
299 break;
300 default:
301 return -EINVAL;
302 }
303 return 0;
304}
305
Greg Kroah-Hartmanea653702005-06-20 21:15:16 -0700306static struct usb_serial_driver safe_device = {
Greg Kroah-Hartman18fcac32005-06-20 21:15:16 -0700307 .driver = {
308 .owner = THIS_MODULE,
Greg Kroah-Hartman269bda12005-06-20 21:15:16 -0700309 .name = "safe_serial",
Greg Kroah-Hartman18fcac32005-06-20 21:15:16 -0700310 },
Linus Torvalds1da177e2005-04-16 15:20:36 -0700311 .id_table = id_table,
Johannes Hölzld9b1b782006-12-17 21:50:24 +0100312 .usb_driver = &safe_driver,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313 .num_ports = 1,
Johan Hovold12e2e522010-05-19 00:01:31 +0200314 .process_read_urb = safe_process_read_urb,
Johan Hovold241c80e2010-05-19 00:01:30 +0200315 .prepare_write_buffer = safe_prepare_write_buffer,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316 .attach = safe_startup,
317};
318
Alan Cox43c8f432008-07-22 11:15:26 +0100319static int __init safe_init(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320{
321 int i, retval;
322
Greg Kroah-Hartmanc197a8d2008-08-18 13:21:04 -0700323 printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
324 DRIVER_DESC "\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325
Alan Cox43c8f432008-07-22 11:15:26 +0100326 /* if we have vendor / product parameters patch them into id list */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700327 if (vendor || product) {
Greg Kroah-Hartmanc197a8d2008-08-18 13:21:04 -0700328 printk(KERN_INFO KBUILD_MODNAME ": vendor: %x product: %x\n",
329 vendor, product);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330
Tobias Klauser52950ed2005-12-11 16:20:08 +0100331 for (i = 0; i < ARRAY_SIZE(id_table); i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332 if (!id_table[i].idVendor && !id_table[i].idProduct) {
333 id_table[i].idVendor = vendor;
334 id_table[i].idProduct = product;
335 break;
336 }
337 }
338 }
339
340 retval = usb_serial_register(&safe_device);
341 if (retval)
342 goto failed_usb_serial_register;
343 retval = usb_register(&safe_driver);
344 if (retval)
345 goto failed_usb_register;
346
347 return 0;
348failed_usb_register:
349 usb_serial_deregister(&safe_device);
350failed_usb_serial_register:
351 return retval;
352}
353
Alan Cox43c8f432008-07-22 11:15:26 +0100354static void __exit safe_exit(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355{
Alan Cox43c8f432008-07-22 11:15:26 +0100356 usb_deregister(&safe_driver);
357 usb_serial_deregister(&safe_device);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358}
359
Alan Cox43c8f432008-07-22 11:15:26 +0100360module_init(safe_init);
361module_exit(safe_exit);