4c4c9432a6
patch below marks various USB tables and variables as const so that they end up in .rodata section and don't cacheline share with things that get written to. For the non-array variables it also allows gcc to optimize more. Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
459 lines
14 KiB
C
459 lines
14 KiB
C
/*
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* Safe Encapsulated USB Serial Driver
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*
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* Copyright (C) 2001 Lineo
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* Copyright (C) 2001 Hewlett-Packard
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* By:
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* Stuart Lynne <sl@lineo.com>, Tom Rushworth <tbr@lineo.com>
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*/
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/*
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* The encapsultaion is designed to overcome difficulties with some USB hardware.
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*
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* While the USB protocol has a CRC over the data while in transit, i.e. while
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* being carried over the bus, there is no end to end protection. If the hardware
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* has any problems getting the data into or out of the USB transmit and receive
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* FIFO's then data can be lost.
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*
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* This protocol adds a two byte trailer to each USB packet to specify the number
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* of bytes of valid data and a 10 bit CRC that will allow the receiver to verify
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* that the entire USB packet was received without error.
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*
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* Because in this case the sender and receiver are the class and function drivers
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* there is now end to end protection.
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*
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* There is an additional option that can be used to force all transmitted packets
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* to be padded to the maximum packet size. This provides a work around for some
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* devices which have problems with small USB packets.
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*
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* Assuming a packetsize of N:
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*
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* 0..N-2 data and optional padding
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*
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* N-2 bits 7-2 - number of bytes of valid data
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* bits 1-0 top two bits of 10 bit CRC
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* N-1 bottom 8 bits of 10 bit CRC
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*
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*
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* | Data Length | 10 bit CRC |
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* + 7 . 6 . 5 . 4 . 3 . 2 . 1 . 0 | 7 . 6 . 5 . 4 . 3 . 2 . 1 . 0 +
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*
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* The 10 bit CRC is computed across the sent data, followed by the trailer with
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* the length set and the CRC set to zero. The CRC is then OR'd into the trailer.
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*
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* When received a 10 bit CRC is computed over the entire frame including the trailer
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* and should be equal to zero.
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*
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* Two module parameters are used to control the encapsulation, if both are
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* turned of the module works as a simple serial device with NO
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* encapsulation.
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*
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* See linux/drivers/usbd/serial_fd for a device function driver
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* implementation of this.
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*
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*/
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#include <linux/config.h>
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#include <linux/kernel.h>
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#include <linux/errno.h>
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#include <linux/init.h>
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#include <linux/slab.h>
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#include <linux/tty.h>
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#include <linux/tty_driver.h>
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#include <linux/tty_flip.h>
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#include <linux/module.h>
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#include <linux/spinlock.h>
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#include <asm/uaccess.h>
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#include <linux/usb.h>
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#include "usb-serial.h"
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#ifndef CONFIG_USB_SAFE_PADDED
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#define CONFIG_USB_SAFE_PADDED 0
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#endif
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static int debug;
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static int safe = 1;
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static int padded = CONFIG_USB_SAFE_PADDED;
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#define DRIVER_VERSION "v0.0b"
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#define DRIVER_AUTHOR "sl@lineo.com, tbr@lineo.com"
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#define DRIVER_DESC "USB Safe Encapsulated Serial"
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MODULE_AUTHOR (DRIVER_AUTHOR);
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MODULE_DESCRIPTION (DRIVER_DESC);
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MODULE_LICENSE("GPL");
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#if defined(CONFIG_USBD_SAFE_SERIAL_VENDOR) && !defined(CONFIG_USBD_SAFE_SERIAL_PRODUCT)
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#error "SAFE_SERIAL_VENDOR defined without SAFE_SERIAL_PRODUCT"
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#endif
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#if ! defined(CONFIG_USBD_SAFE_SERIAL_VENDOR)
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static __u16 vendor; // no default
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static __u16 product; // no default
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module_param(vendor, ushort, 0);
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MODULE_PARM_DESC(vendor, "User specified USB idVendor (required)");
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module_param(product, ushort, 0);
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MODULE_PARM_DESC(product, "User specified USB idProduct (required)");
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#endif
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module_param(debug, bool, S_IRUGO | S_IWUSR);
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MODULE_PARM_DESC(debug, "Debug enabled or not");
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module_param(safe, bool, 0);
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MODULE_PARM_DESC(safe, "Turn Safe Encapsulation On/Off");
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module_param(padded, bool, 0);
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MODULE_PARM_DESC(padded, "Pad to full wMaxPacketSize On/Off");
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#define CDC_DEVICE_CLASS 0x02
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#define CDC_INTERFACE_CLASS 0x02
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#define CDC_INTERFACE_SUBCLASS 0x06
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#define LINEO_INTERFACE_CLASS 0xff
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#define LINEO_INTERFACE_SUBCLASS_SAFENET 0x01
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#define LINEO_SAFENET_CRC 0x01
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#define LINEO_SAFENET_CRC_PADDED 0x02
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#define LINEO_INTERFACE_SUBCLASS_SAFESERIAL 0x02
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#define LINEO_SAFESERIAL_CRC 0x01
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#define LINEO_SAFESERIAL_CRC_PADDED 0x02
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#define MY_USB_DEVICE(vend,prod,dc,ic,isc) \
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.match_flags = USB_DEVICE_ID_MATCH_DEVICE | USB_DEVICE_ID_MATCH_DEV_CLASS | \
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USB_DEVICE_ID_MATCH_INT_CLASS | USB_DEVICE_ID_MATCH_INT_SUBCLASS, \
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.idVendor = (vend), \
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.idProduct = (prod),\
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.bDeviceClass = (dc),\
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.bInterfaceClass = (ic), \
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.bInterfaceSubClass = (isc),
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static struct usb_device_id id_table[] = {
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{MY_USB_DEVICE (0x49f, 0xffff, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, // Itsy
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{MY_USB_DEVICE (0x3f0, 0x2101, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, // Calypso
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{MY_USB_DEVICE (0x4dd, 0x8001, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, // Iris
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{MY_USB_DEVICE (0x4dd, 0x8002, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, // Collie
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{MY_USB_DEVICE (0x4dd, 0x8003, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, // Collie
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{MY_USB_DEVICE (0x4dd, 0x8004, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, // Collie
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{MY_USB_DEVICE (0x5f9, 0xffff, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, // Sharp tmp
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#if defined(CONFIG_USB_SAFE_SERIAL_VENDOR)
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{MY_USB_DEVICE
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(CONFIG_USB_SAFE_SERIAL_VENDOR, CONFIG_USB_SAFE_SERIAL_PRODUCT, CDC_DEVICE_CLASS,
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LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)},
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#endif
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// extra null entry for module
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// vendor/produc parameters
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{MY_USB_DEVICE (0, 0, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)},
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{} // terminating entry
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};
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MODULE_DEVICE_TABLE (usb, id_table);
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static struct usb_driver safe_driver = {
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.name = "safe_serial",
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.probe = usb_serial_probe,
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.disconnect = usb_serial_disconnect,
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.id_table = id_table,
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.no_dynamic_id = 1,
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};
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static const __u16 crc10_table[256] = {
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0x000, 0x233, 0x255, 0x066, 0x299, 0x0aa, 0x0cc, 0x2ff, 0x301, 0x132, 0x154, 0x367, 0x198, 0x3ab, 0x3cd, 0x1fe,
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0x031, 0x202, 0x264, 0x057, 0x2a8, 0x09b, 0x0fd, 0x2ce, 0x330, 0x103, 0x165, 0x356, 0x1a9, 0x39a, 0x3fc, 0x1cf,
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0x062, 0x251, 0x237, 0x004, 0x2fb, 0x0c8, 0x0ae, 0x29d, 0x363, 0x150, 0x136, 0x305, 0x1fa, 0x3c9, 0x3af, 0x19c,
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0x053, 0x260, 0x206, 0x035, 0x2ca, 0x0f9, 0x09f, 0x2ac, 0x352, 0x161, 0x107, 0x334, 0x1cb, 0x3f8, 0x39e, 0x1ad,
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0x0c4, 0x2f7, 0x291, 0x0a2, 0x25d, 0x06e, 0x008, 0x23b, 0x3c5, 0x1f6, 0x190, 0x3a3, 0x15c, 0x36f, 0x309, 0x13a,
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0x0f5, 0x2c6, 0x2a0, 0x093, 0x26c, 0x05f, 0x039, 0x20a, 0x3f4, 0x1c7, 0x1a1, 0x392, 0x16d, 0x35e, 0x338, 0x10b,
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0x0a6, 0x295, 0x2f3, 0x0c0, 0x23f, 0x00c, 0x06a, 0x259, 0x3a7, 0x194, 0x1f2, 0x3c1, 0x13e, 0x30d, 0x36b, 0x158,
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0x097, 0x2a4, 0x2c2, 0x0f1, 0x20e, 0x03d, 0x05b, 0x268, 0x396, 0x1a5, 0x1c3, 0x3f0, 0x10f, 0x33c, 0x35a, 0x169,
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0x188, 0x3bb, 0x3dd, 0x1ee, 0x311, 0x122, 0x144, 0x377, 0x289, 0x0ba, 0x0dc, 0x2ef, 0x010, 0x223, 0x245, 0x076,
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0x1b9, 0x38a, 0x3ec, 0x1df, 0x320, 0x113, 0x175, 0x346, 0x2b8, 0x08b, 0x0ed, 0x2de, 0x021, 0x212, 0x274, 0x047,
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0x1ea, 0x3d9, 0x3bf, 0x18c, 0x373, 0x140, 0x126, 0x315, 0x2eb, 0x0d8, 0x0be, 0x28d, 0x072, 0x241, 0x227, 0x014,
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0x1db, 0x3e8, 0x38e, 0x1bd, 0x342, 0x171, 0x117, 0x324, 0x2da, 0x0e9, 0x08f, 0x2bc, 0x043, 0x270, 0x216, 0x025,
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0x14c, 0x37f, 0x319, 0x12a, 0x3d5, 0x1e6, 0x180, 0x3b3, 0x24d, 0x07e, 0x018, 0x22b, 0x0d4, 0x2e7, 0x281, 0x0b2,
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0x17d, 0x34e, 0x328, 0x11b, 0x3e4, 0x1d7, 0x1b1, 0x382, 0x27c, 0x04f, 0x029, 0x21a, 0x0e5, 0x2d6, 0x2b0, 0x083,
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0x12e, 0x31d, 0x37b, 0x148, 0x3b7, 0x184, 0x1e2, 0x3d1, 0x22f, 0x01c, 0x07a, 0x249, 0x0b6, 0x285, 0x2e3, 0x0d0,
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0x11f, 0x32c, 0x34a, 0x179, 0x386, 0x1b5, 0x1d3, 0x3e0, 0x21e, 0x02d, 0x04b, 0x278, 0x087, 0x2b4, 0x2d2, 0x0e1,
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};
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#define CRC10_INITFCS 0x000 // Initial FCS value
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#define CRC10_GOODFCS 0x000 // Good final FCS value
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#define CRC10_FCS(fcs, c) ( (((fcs) << 8) & 0x3ff) ^ crc10_table[((fcs) >> 2) & 0xff] ^ (c))
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/**
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* fcs_compute10 - memcpy and calculate 10 bit CRC across buffer
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* @sp: pointer to buffer
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* @len: number of bytes
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* @fcs: starting FCS
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*
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* Perform a memcpy and calculate fcs using ppp 10bit CRC algorithm. Return
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* new 10 bit FCS.
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*/
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static __u16 __inline__ fcs_compute10 (unsigned char *sp, int len, __u16 fcs)
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{
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for (; len-- > 0; fcs = CRC10_FCS (fcs, *sp++));
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return fcs;
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}
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static void safe_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
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{
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struct usb_serial_port *port = (struct usb_serial_port *) urb->context;
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unsigned char *data = urb->transfer_buffer;
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unsigned char length = urb->actual_length;
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int i;
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int result;
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dbg ("%s", __FUNCTION__);
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if (urb->status) {
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dbg ("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
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return;
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}
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dbg ("safe_read_bulk_callback length: %d", port->read_urb->actual_length);
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#ifdef ECHO_RCV
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{
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int i;
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unsigned char *cp = port->read_urb->transfer_buffer;
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for (i = 0; i < port->read_urb->actual_length; i++) {
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if ((i % 32) == 0) {
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printk ("\nru[%02x] ", i);
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}
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printk ("%02x ", *cp++);
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}
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printk ("\n");
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}
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#endif
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if (safe) {
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__u16 fcs;
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if (!(fcs = fcs_compute10 (data, length, CRC10_INITFCS))) {
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int actual_length = data[length - 2] >> 2;
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if (actual_length <= (length - 2)) {
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info ("%s - actual: %d", __FUNCTION__, actual_length);
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for (i = 0; i < actual_length; i++) {
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tty_insert_flip_char (port->tty, data[i], 0);
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}
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tty_flip_buffer_push (port->tty);
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} else {
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err ("%s - inconsistent lengths %d:%d", __FUNCTION__,
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actual_length, length);
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}
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} else {
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err ("%s - bad CRC %x", __FUNCTION__, fcs);
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}
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} else {
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for (i = 0; i < length; i++) {
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tty_insert_flip_char (port->tty, data[i], 0);
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}
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tty_flip_buffer_push (port->tty);
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}
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/* Continue trying to always read */
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usb_fill_bulk_urb (urb, port->serial->dev,
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usb_rcvbulkpipe (port->serial->dev, port->bulk_in_endpointAddress),
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urb->transfer_buffer, urb->transfer_buffer_length,
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safe_read_bulk_callback, port);
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if ((result = usb_submit_urb (urb, GFP_ATOMIC))) {
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err ("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
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}
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}
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static int safe_write (struct usb_serial_port *port, const unsigned char *buf, int count)
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{
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unsigned char *data;
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int result;
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int i;
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int packet_length;
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dbg ("safe_write port: %p %d urb: %p count: %d", port, port->number, port->write_urb,
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count);
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if (!port->write_urb) {
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dbg ("%s - write urb NULL", __FUNCTION__);
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return (0);
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}
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dbg ("safe_write write_urb: %d transfer_buffer_length",
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port->write_urb->transfer_buffer_length);
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if (!port->write_urb->transfer_buffer_length) {
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dbg ("%s - write urb transfer_buffer_length zero", __FUNCTION__);
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return (0);
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}
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if (count == 0) {
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dbg ("%s - write request of 0 bytes", __FUNCTION__);
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return (0);
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}
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spin_lock(&port->lock);
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if (port->write_urb_busy) {
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spin_unlock(&port->lock);
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dbg("%s - already writing", __FUNCTION__);
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return 0;
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}
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port->write_urb_busy = 1;
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spin_unlock(&port->lock);
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packet_length = port->bulk_out_size; // get max packetsize
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i = packet_length - (safe ? 2 : 0); // get bytes to send
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count = (count > i) ? i : count;
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// get the data into the transfer buffer
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data = port->write_urb->transfer_buffer;
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memset (data, '0', packet_length);
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memcpy (data, buf, count);
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if (safe) {
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__u16 fcs;
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// pad if necessary
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if (!padded) {
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packet_length = count + 2;
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}
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// set count
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data[packet_length - 2] = count << 2;
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data[packet_length - 1] = 0;
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// compute fcs and insert into trailer
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fcs = fcs_compute10 (data, packet_length, CRC10_INITFCS);
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data[packet_length - 2] |= fcs >> 8;
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data[packet_length - 1] |= fcs & 0xff;
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// set length to send
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port->write_urb->transfer_buffer_length = packet_length;
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} else {
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port->write_urb->transfer_buffer_length = count;
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}
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usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count, port->write_urb->transfer_buffer);
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#ifdef ECHO_TX
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{
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int i;
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unsigned char *cp = port->write_urb->transfer_buffer;
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for (i = 0; i < port->write_urb->transfer_buffer_length; i++) {
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if ((i % 32) == 0) {
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printk ("\nsu[%02x] ", i);
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}
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printk ("%02x ", *cp++);
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}
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printk ("\n");
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}
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#endif
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port->write_urb->dev = port->serial->dev;
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if ((result = usb_submit_urb (port->write_urb, GFP_KERNEL))) {
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port->write_urb_busy = 0;
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err ("%s - failed submitting write urb, error %d", __FUNCTION__, result);
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return 0;
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}
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dbg ("%s urb: %p submitted", __FUNCTION__, port->write_urb);
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return (count);
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}
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static int safe_write_room (struct usb_serial_port *port)
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{
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int room = 0; // Default: no room
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dbg ("%s", __FUNCTION__);
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if (port->write_urb_busy)
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room = port->bulk_out_size - (safe ? 2 : 0);
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if (room) {
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dbg ("safe_write_room returns %d", room);
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}
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return (room);
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}
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static int safe_startup (struct usb_serial *serial)
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{
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switch (serial->interface->cur_altsetting->desc.bInterfaceProtocol) {
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case LINEO_SAFESERIAL_CRC:
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break;
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case LINEO_SAFESERIAL_CRC_PADDED:
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padded = 1;
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break;
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default:
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return -EINVAL;
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}
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return 0;
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}
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static struct usb_serial_driver safe_device = {
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.driver = {
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.owner = THIS_MODULE,
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.name = "safe_serial",
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},
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.id_table = id_table,
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.num_interrupt_in = NUM_DONT_CARE,
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.num_bulk_in = NUM_DONT_CARE,
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.num_bulk_out = NUM_DONT_CARE,
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.num_ports = 1,
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.write = safe_write,
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.write_room = safe_write_room,
|
|
.read_bulk_callback = safe_read_bulk_callback,
|
|
.attach = safe_startup,
|
|
};
|
|
|
|
static int __init safe_init (void)
|
|
{
|
|
int i, retval;
|
|
|
|
info (DRIVER_VERSION " " DRIVER_AUTHOR);
|
|
info (DRIVER_DESC);
|
|
info ("vendor: %x product: %x safe: %d padded: %d\n", vendor, product, safe, padded);
|
|
|
|
// if we have vendor / product parameters patch them into id list
|
|
if (vendor || product) {
|
|
info ("vendor: %x product: %x\n", vendor, product);
|
|
|
|
for (i = 0; i < (sizeof (id_table) / sizeof (struct usb_device_id)); i++) {
|
|
if (!id_table[i].idVendor && !id_table[i].idProduct) {
|
|
id_table[i].idVendor = vendor;
|
|
id_table[i].idProduct = product;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
retval = usb_serial_register(&safe_device);
|
|
if (retval)
|
|
goto failed_usb_serial_register;
|
|
retval = usb_register(&safe_driver);
|
|
if (retval)
|
|
goto failed_usb_register;
|
|
|
|
return 0;
|
|
failed_usb_register:
|
|
usb_serial_deregister(&safe_device);
|
|
failed_usb_serial_register:
|
|
return retval;
|
|
}
|
|
|
|
static void __exit safe_exit (void)
|
|
{
|
|
usb_deregister (&safe_driver);
|
|
usb_serial_deregister (&safe_device);
|
|
}
|
|
|
|
module_init (safe_init);
|
|
module_exit (safe_exit);
|