Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Safe Encapsulated USB Serial Driver |
| 3 | * |
Johan Hovold | 241c80e | 2010-05-19 00:01:30 +0200 | [diff] [blame] | 4 | * Copyright (C) 2010 Johan Hovold <jhovold@gmail.com> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 5 | * 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 Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 17 | /* |
| 18 | * The encapsultaion is designed to overcome difficulties with some USB |
| 19 | * hardware. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | * |
| 21 | * While the USB protocol has a CRC over the data while in transit, i.e. while |
Alan Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 22 | * 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 Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | * |
Alan Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 26 | * 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 Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 29 | * |
Alan Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 30 | * Because in this case the sender and receiver are the class and function |
| 31 | * drivers there is now end to end protection. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 32 | * |
Alan Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 33 | * 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 Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | * |
| 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 Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 49 | * 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 Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 52 | * |
Alan Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 53 | * When received a 10 bit CRC is computed over the entire frame including |
| 54 | * the trailer and should be equal to zero. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 55 | * |
| 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 Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 66 | #include <linux/kernel.h> |
| 67 | #include <linux/errno.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 68 | #include <linux/gfp.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 69 | #include <linux/init.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 70 | #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 Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 75 | #include <linux/uaccess.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 76 | #include <linux/usb.h> |
Greg Kroah-Hartman | a969888 | 2006-07-11 21:22:58 -0700 | [diff] [blame] | 77 | #include <linux/usb/serial.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 78 | |
| 79 | |
Robert P. J. Day | 3aec6e2 | 2007-07-30 06:38:31 -0400 | [diff] [blame] | 80 | #ifndef CONFIG_USB_SERIAL_SAFE_PADDED |
| 81 | #define CONFIG_USB_SERIAL_SAFE_PADDED 0 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 82 | #endif |
| 83 | |
Rusty Russell | 90ab5ee | 2012-01-13 09:32:20 +1030 | [diff] [blame] | 84 | static bool debug; |
| 85 | static bool safe = 1; |
| 86 | static bool padded = CONFIG_USB_SERIAL_SAFE_PADDED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 87 | |
Johan Hovold | 241c80e | 2010-05-19 00:01:30 +0200 | [diff] [blame] | 88 | #define DRIVER_VERSION "v0.1" |
| 89 | #define DRIVER_AUTHOR "sl@lineo.com, tbr@lineo.com, Johan Hovold <jhovold@gmail.com>" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 90 | #define DRIVER_DESC "USB Safe Encapsulated Serial" |
| 91 | |
Alan Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 92 | MODULE_AUTHOR(DRIVER_AUTHOR); |
| 93 | MODULE_DESCRIPTION(DRIVER_DESC); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 94 | MODULE_LICENSE("GPL"); |
| 95 | |
Alan Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 96 | static __u16 vendor; /* no default */ |
| 97 | static __u16 product; /* no default */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 98 | module_param(vendor, ushort, 0); |
| 99 | MODULE_PARM_DESC(vendor, "User specified USB idVendor (required)"); |
| 100 | module_param(product, ushort, 0); |
| 101 | MODULE_PARM_DESC(product, "User specified USB idProduct (required)"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 102 | |
| 103 | module_param(debug, bool, S_IRUGO | S_IWUSR); |
| 104 | MODULE_PARM_DESC(debug, "Debug enabled or not"); |
| 105 | |
| 106 | module_param(safe, bool, 0); |
| 107 | MODULE_PARM_DESC(safe, "Turn Safe Encapsulation On/Off"); |
| 108 | |
| 109 | module_param(padded, bool, 0); |
| 110 | MODULE_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 Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 128 | #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 Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 138 | |
| 139 | static struct usb_device_id id_table[] = { |
Alan Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 140 | {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 Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 150 | }; |
| 151 | |
Alan Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 152 | MODULE_DEVICE_TABLE(usb, id_table); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 153 | |
Arjan van de Ven | 4c4c943 | 2005-11-29 09:43:42 +0100 | [diff] [blame] | 154 | static const __u16 crc10_table[256] = { |
Alan Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 155 | 0x000, 0x233, 0x255, 0x066, 0x299, 0x0aa, 0x0cc, 0x2ff, |
| 156 | 0x301, 0x132, 0x154, 0x367, 0x198, 0x3ab, 0x3cd, 0x1fe, |
| 157 | 0x031, 0x202, 0x264, 0x057, 0x2a8, 0x09b, 0x0fd, 0x2ce, |
| 158 | 0x330, 0x103, 0x165, 0x356, 0x1a9, 0x39a, 0x3fc, 0x1cf, |
| 159 | 0x062, 0x251, 0x237, 0x004, 0x2fb, 0x0c8, 0x0ae, 0x29d, |
| 160 | 0x363, 0x150, 0x136, 0x305, 0x1fa, 0x3c9, 0x3af, 0x19c, |
| 161 | 0x053, 0x260, 0x206, 0x035, 0x2ca, 0x0f9, 0x09f, 0x2ac, |
| 162 | 0x352, 0x161, 0x107, 0x334, 0x1cb, 0x3f8, 0x39e, 0x1ad, |
| 163 | 0x0c4, 0x2f7, 0x291, 0x0a2, 0x25d, 0x06e, 0x008, 0x23b, |
| 164 | 0x3c5, 0x1f6, 0x190, 0x3a3, 0x15c, 0x36f, 0x309, 0x13a, |
| 165 | 0x0f5, 0x2c6, 0x2a0, 0x093, 0x26c, 0x05f, 0x039, 0x20a, |
| 166 | 0x3f4, 0x1c7, 0x1a1, 0x392, 0x16d, 0x35e, 0x338, 0x10b, |
| 167 | 0x0a6, 0x295, 0x2f3, 0x0c0, 0x23f, 0x00c, 0x06a, 0x259, |
| 168 | 0x3a7, 0x194, 0x1f2, 0x3c1, 0x13e, 0x30d, 0x36b, 0x158, |
| 169 | 0x097, 0x2a4, 0x2c2, 0x0f1, 0x20e, 0x03d, 0x05b, 0x268, |
| 170 | 0x396, 0x1a5, 0x1c3, 0x3f0, 0x10f, 0x33c, 0x35a, 0x169, |
| 171 | 0x188, 0x3bb, 0x3dd, 0x1ee, 0x311, 0x122, 0x144, 0x377, |
| 172 | 0x289, 0x0ba, 0x0dc, 0x2ef, 0x010, 0x223, 0x245, 0x076, |
| 173 | 0x1b9, 0x38a, 0x3ec, 0x1df, 0x320, 0x113, 0x175, 0x346, |
| 174 | 0x2b8, 0x08b, 0x0ed, 0x2de, 0x021, 0x212, 0x274, 0x047, |
| 175 | 0x1ea, 0x3d9, 0x3bf, 0x18c, 0x373, 0x140, 0x126, 0x315, |
| 176 | 0x2eb, 0x0d8, 0x0be, 0x28d, 0x072, 0x241, 0x227, 0x014, |
| 177 | 0x1db, 0x3e8, 0x38e, 0x1bd, 0x342, 0x171, 0x117, 0x324, |
| 178 | 0x2da, 0x0e9, 0x08f, 0x2bc, 0x043, 0x270, 0x216, 0x025, |
| 179 | 0x14c, 0x37f, 0x319, 0x12a, 0x3d5, 0x1e6, 0x180, 0x3b3, |
| 180 | 0x24d, 0x07e, 0x018, 0x22b, 0x0d4, 0x2e7, 0x281, 0x0b2, |
| 181 | 0x17d, 0x34e, 0x328, 0x11b, 0x3e4, 0x1d7, 0x1b1, 0x382, |
| 182 | 0x27c, 0x04f, 0x029, 0x21a, 0x0e5, 0x2d6, 0x2b0, 0x083, |
| 183 | 0x12e, 0x31d, 0x37b, 0x148, 0x3b7, 0x184, 0x1e2, 0x3d1, |
| 184 | 0x22f, 0x01c, 0x07a, 0x249, 0x0b6, 0x285, 0x2e3, 0x0d0, |
| 185 | 0x11f, 0x32c, 0x34a, 0x179, 0x386, 0x1b5, 0x1d3, 0x3e0, |
| 186 | 0x21e, 0x02d, 0x04b, 0x278, 0x087, 0x2b4, 0x2d2, 0x0e1, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 187 | }; |
| 188 | |
Alan Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 189 | #define CRC10_INITFCS 0x000 /* Initial FCS value */ |
| 190 | #define CRC10_GOODFCS 0x000 /* Good final FCS value */ |
| 191 | #define CRC10_FCS(fcs, c) ((((fcs) << 8) & 0x3ff) ^ crc10_table[((fcs) >> 2) & 0xff] ^ (c)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 192 | |
Alan Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 193 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 194 | * fcs_compute10 - memcpy and calculate 10 bit CRC across buffer |
| 195 | * @sp: pointer to buffer |
| 196 | * @len: number of bytes |
| 197 | * @fcs: starting FCS |
| 198 | * |
| 199 | * Perform a memcpy and calculate fcs using ppp 10bit CRC algorithm. Return |
| 200 | * new 10 bit FCS. |
| 201 | */ |
Alan Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 202 | static __u16 __inline__ fcs_compute10(unsigned char *sp, int len, __u16 fcs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 203 | { |
Alan Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 204 | for (; len-- > 0; fcs = CRC10_FCS(fcs, *sp++)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | return fcs; |
| 206 | } |
| 207 | |
Johan Hovold | 12e2e52 | 2010-05-19 00:01:31 +0200 | [diff] [blame] | 208 | static void safe_process_read_urb(struct urb *urb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 209 | { |
Johan Hovold | 12e2e52 | 2010-05-19 00:01:31 +0200 | [diff] [blame] | 210 | struct usb_serial_port *port = urb->context; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 211 | unsigned char *data = urb->transfer_buffer; |
| 212 | unsigned char length = urb->actual_length; |
Johan Hovold | 6d1bf48 | 2010-05-19 00:01:32 +0200 | [diff] [blame] | 213 | int actual_length; |
Alan Cox | 4a90f09 | 2008-10-13 10:39:46 +0100 | [diff] [blame] | 214 | struct tty_struct *tty; |
Johan Hovold | 6d1bf48 | 2010-05-19 00:01:32 +0200 | [diff] [blame] | 215 | __u16 fcs; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 216 | |
Johan Hovold | 12e2e52 | 2010-05-19 00:01:31 +0200 | [diff] [blame] | 217 | if (!length) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 218 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 219 | |
Alan Cox | 4a90f09 | 2008-10-13 10:39:46 +0100 | [diff] [blame] | 220 | tty = tty_port_tty_get(&port->port); |
Johan Hovold | 12e2e52 | 2010-05-19 00:01:31 +0200 | [diff] [blame] | 221 | if (!tty) |
| 222 | return; |
| 223 | |
Johan Hovold | 6d1bf48 | 2010-05-19 00:01:32 +0200 | [diff] [blame] | 224 | if (!safe) |
| 225 | goto out; |
| 226 | |
| 227 | fcs = fcs_compute10(data, length, CRC10_INITFCS); |
| 228 | if (fcs) { |
| 229 | dev_err(&port->dev, "%s - bad CRC %x\n", __func__, fcs); |
| 230 | goto err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 231 | } |
Johan Hovold | 12e2e52 | 2010-05-19 00:01:31 +0200 | [diff] [blame] | 232 | |
Johan Hovold | 6d1bf48 | 2010-05-19 00:01:32 +0200 | [diff] [blame] | 233 | actual_length = data[length - 2] >> 2; |
| 234 | if (actual_length > (length - 2)) { |
| 235 | dev_err(&port->dev, "%s - inconsistent lengths %d:%d\n", |
| 236 | __func__, actual_length, length); |
| 237 | goto err; |
| 238 | } |
| 239 | dev_info(&urb->dev->dev, "%s - actual: %d\n", __func__, actual_length); |
| 240 | length = actual_length; |
| 241 | out: |
| 242 | tty_insert_flip_string(tty, data, length); |
| 243 | tty_flip_buffer_push(tty); |
| 244 | err: |
Alan Cox | 4a90f09 | 2008-10-13 10:39:46 +0100 | [diff] [blame] | 245 | tty_kref_put(tty); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 246 | } |
| 247 | |
Johan Hovold | 241c80e | 2010-05-19 00:01:30 +0200 | [diff] [blame] | 248 | static int safe_prepare_write_buffer(struct usb_serial_port *port, |
| 249 | void *dest, size_t size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 250 | { |
Johan Hovold | 241c80e | 2010-05-19 00:01:30 +0200 | [diff] [blame] | 251 | unsigned char *buf = dest; |
| 252 | int count; |
| 253 | int trailer_len; |
| 254 | int pkt_len; |
| 255 | __u16 fcs; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 256 | |
Johan Hovold | 241c80e | 2010-05-19 00:01:30 +0200 | [diff] [blame] | 257 | trailer_len = safe ? 2 : 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 258 | |
Johan Hovold | 241c80e | 2010-05-19 00:01:30 +0200 | [diff] [blame] | 259 | count = kfifo_out_locked(&port->write_fifo, buf, size - trailer_len, |
| 260 | &port->lock); |
| 261 | if (!safe) |
| 262 | return count; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 263 | |
Johan Hovold | 241c80e | 2010-05-19 00:01:30 +0200 | [diff] [blame] | 264 | /* pad if necessary */ |
| 265 | if (padded) { |
| 266 | pkt_len = size; |
| 267 | memset(buf + count, '0', pkt_len - count - trailer_len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 268 | } else { |
Johan Hovold | 241c80e | 2010-05-19 00:01:30 +0200 | [diff] [blame] | 269 | pkt_len = count + trailer_len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 270 | } |
| 271 | |
Johan Hovold | 241c80e | 2010-05-19 00:01:30 +0200 | [diff] [blame] | 272 | /* set count */ |
| 273 | buf[pkt_len - 2] = count << 2; |
| 274 | buf[pkt_len - 1] = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 275 | |
Johan Hovold | 241c80e | 2010-05-19 00:01:30 +0200 | [diff] [blame] | 276 | /* compute fcs and insert into trailer */ |
| 277 | fcs = fcs_compute10(buf, pkt_len, CRC10_INITFCS); |
| 278 | buf[pkt_len - 2] |= fcs >> 8; |
| 279 | buf[pkt_len - 1] |= fcs & 0xff; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 280 | |
Johan Hovold | 241c80e | 2010-05-19 00:01:30 +0200 | [diff] [blame] | 281 | return pkt_len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 282 | } |
| 283 | |
Alan Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 284 | static int safe_startup(struct usb_serial *serial) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 285 | { |
| 286 | switch (serial->interface->cur_altsetting->desc.bInterfaceProtocol) { |
| 287 | case LINEO_SAFESERIAL_CRC: |
| 288 | break; |
| 289 | case LINEO_SAFESERIAL_CRC_PADDED: |
| 290 | padded = 1; |
| 291 | break; |
| 292 | default: |
| 293 | return -EINVAL; |
| 294 | } |
| 295 | return 0; |
| 296 | } |
| 297 | |
Greg Kroah-Hartman | ea65370 | 2005-06-20 21:15:16 -0700 | [diff] [blame] | 298 | static struct usb_serial_driver safe_device = { |
Greg Kroah-Hartman | 18fcac3 | 2005-06-20 21:15:16 -0700 | [diff] [blame] | 299 | .driver = { |
| 300 | .owner = THIS_MODULE, |
Greg Kroah-Hartman | 269bda1 | 2005-06-20 21:15:16 -0700 | [diff] [blame] | 301 | .name = "safe_serial", |
Greg Kroah-Hartman | 18fcac3 | 2005-06-20 21:15:16 -0700 | [diff] [blame] | 302 | }, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 303 | .id_table = id_table, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 304 | .num_ports = 1, |
Johan Hovold | 12e2e52 | 2010-05-19 00:01:31 +0200 | [diff] [blame] | 305 | .process_read_urb = safe_process_read_urb, |
Johan Hovold | 241c80e | 2010-05-19 00:01:30 +0200 | [diff] [blame] | 306 | .prepare_write_buffer = safe_prepare_write_buffer, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 307 | .attach = safe_startup, |
| 308 | }; |
| 309 | |
Alan Stern | d860322 | 2012-02-23 14:57:25 -0500 | [diff] [blame] | 310 | static struct usb_serial_driver * const serial_drivers[] = { |
| 311 | &safe_device, NULL |
| 312 | }; |
| 313 | |
Alan Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 314 | static int __init safe_init(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 315 | { |
Alan Stern | d860322 | 2012-02-23 14:57:25 -0500 | [diff] [blame] | 316 | int i; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 317 | |
Greg Kroah-Hartman | c197a8d | 2008-08-18 13:21:04 -0700 | [diff] [blame] | 318 | printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":" |
| 319 | DRIVER_DESC "\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 320 | |
Alan Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 321 | /* if we have vendor / product parameters patch them into id list */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 322 | if (vendor || product) { |
Greg Kroah-Hartman | c197a8d | 2008-08-18 13:21:04 -0700 | [diff] [blame] | 323 | printk(KERN_INFO KBUILD_MODNAME ": vendor: %x product: %x\n", |
| 324 | vendor, product); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 325 | |
Tobias Klauser | 52950ed | 2005-12-11 16:20:08 +0100 | [diff] [blame] | 326 | for (i = 0; i < ARRAY_SIZE(id_table); i++) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 327 | if (!id_table[i].idVendor && !id_table[i].idProduct) { |
| 328 | id_table[i].idVendor = vendor; |
| 329 | id_table[i].idProduct = product; |
| 330 | break; |
| 331 | } |
| 332 | } |
| 333 | } |
| 334 | |
Greg Kroah-Hartman | 68e2411 | 2012-05-08 15:46:14 -0700 | [diff] [blame] | 335 | return usb_serial_register_drivers(serial_drivers, KBUILD_MODNAME, id_table); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 336 | } |
| 337 | |
Alan Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 338 | static void __exit safe_exit(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 339 | { |
Greg Kroah-Hartman | 68e2411 | 2012-05-08 15:46:14 -0700 | [diff] [blame] | 340 | usb_serial_deregister_drivers(serial_drivers); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 341 | } |
| 342 | |
Alan Cox | 43c8f43 | 2008-07-22 11:15:26 +0100 | [diff] [blame] | 343 | module_init(safe_init); |
| 344 | module_exit(safe_exit); |