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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/usb/serial/safe_serial.c
downloadlinux-stericsson-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/usb/serial/safe_serial.c')
-rw-r--r--drivers/usb/serial/safe_serial.c451
1 files changed, 451 insertions, 0 deletions
diff --git a/drivers/usb/serial/safe_serial.c b/drivers/usb/serial/safe_serial.c
new file mode 100644
index 000000000000..0e85ed6c6c19
--- /dev/null
+++ b/drivers/usb/serial/safe_serial.c
@@ -0,0 +1,451 @@
+/*
+ * Safe Encapsulated USB Serial Driver
+ *
+ * Copyright (C) 2001 Lineo
+ * Copyright (C) 2001 Hewlett-Packard
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * By:
+ * Stuart Lynne <sl@lineo.com>, Tom Rushworth <tbr@lineo.com>
+ */
+
+/*
+ * The encapsultaion is designed to overcome difficulties with some USB hardware.
+ *
+ * While the USB protocol has a CRC over the data while in transit, i.e. while
+ * being carried over the bus, there is no end to end protection. If the hardware
+ * has any problems getting the data into or out of the USB transmit and receive
+ * FIFO's then data can be lost.
+ *
+ * This protocol adds a two byte trailer to each USB packet to specify the number
+ * of bytes of valid data and a 10 bit CRC that will allow the receiver to verify
+ * that the entire USB packet was received without error.
+ *
+ * Because in this case the sender and receiver are the class and function drivers
+ * there is now end to end protection.
+ *
+ * There is an additional option that can be used to force all transmitted packets
+ * to be padded to the maximum packet size. This provides a work around for some
+ * devices which have problems with small USB packets.
+ *
+ * Assuming a packetsize of N:
+ *
+ * 0..N-2 data and optional padding
+ *
+ * N-2 bits 7-2 - number of bytes of valid data
+ * bits 1-0 top two bits of 10 bit CRC
+ * N-1 bottom 8 bits of 10 bit CRC
+ *
+ *
+ * | Data Length | 10 bit CRC |
+ * + 7 . 6 . 5 . 4 . 3 . 2 . 1 . 0 | 7 . 6 . 5 . 4 . 3 . 2 . 1 . 0 +
+ *
+ * The 10 bit CRC is computed across the sent data, followed by the trailer with
+ * the length set and the CRC set to zero. The CRC is then OR'd into the trailer.
+ *
+ * When received a 10 bit CRC is computed over the entire frame including the trailer
+ * and should be equal to zero.
+ *
+ * Two module parameters are used to control the encapsulation, if both are
+ * turned of the module works as a simple serial device with NO
+ * encapsulation.
+ *
+ * See linux/drivers/usbd/serial_fd for a device function driver
+ * implementation of this.
+ *
+ */
+
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/tty.h>
+#include <linux/tty_driver.h>
+#include <linux/tty_flip.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <asm/uaccess.h>
+#include <linux/usb.h>
+#include "usb-serial.h"
+
+
+#ifndef CONFIG_USB_SAFE_PADDED
+#define CONFIG_USB_SAFE_PADDED 0
+#endif
+
+static int debug;
+static int safe = 1;
+static int padded = CONFIG_USB_SAFE_PADDED;
+
+#define DRIVER_VERSION "v0.0b"
+#define DRIVER_AUTHOR "sl@lineo.com, tbr@lineo.com"
+#define DRIVER_DESC "USB Safe Encapsulated Serial"
+
+MODULE_AUTHOR (DRIVER_AUTHOR);
+MODULE_DESCRIPTION (DRIVER_DESC);
+MODULE_LICENSE("GPL");
+
+#if defined(CONFIG_USBD_SAFE_SERIAL_VENDOR) && !defined(CONFIG_USBD_SAFE_SERIAL_PRODUCT)
+#abort "SAFE_SERIAL_VENDOR defined without SAFE_SERIAL_PRODUCT"
+#endif
+
+#if ! defined(CONFIG_USBD_SAFE_SERIAL_VENDOR)
+static __u16 vendor; // no default
+static __u16 product; // no default
+module_param(vendor, ushort, 0);
+MODULE_PARM_DESC(vendor, "User specified USB idVendor (required)");
+module_param(product, ushort, 0);
+MODULE_PARM_DESC(product, "User specified USB idProduct (required)");
+#endif
+
+module_param(debug, bool, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(debug, "Debug enabled or not");
+
+module_param(safe, bool, 0);
+MODULE_PARM_DESC(safe, "Turn Safe Encapsulation On/Off");
+
+module_param(padded, bool, 0);
+MODULE_PARM_DESC(padded, "Pad to full wMaxPacketSize On/Off");
+
+#define CDC_DEVICE_CLASS 0x02
+
+#define CDC_INTERFACE_CLASS 0x02
+#define CDC_INTERFACE_SUBCLASS 0x06
+
+#define LINEO_INTERFACE_CLASS 0xff
+
+#define LINEO_INTERFACE_SUBCLASS_SAFENET 0x01
+#define LINEO_SAFENET_CRC 0x01
+#define LINEO_SAFENET_CRC_PADDED 0x02
+
+#define LINEO_INTERFACE_SUBCLASS_SAFESERIAL 0x02
+#define LINEO_SAFESERIAL_CRC 0x01
+#define LINEO_SAFESERIAL_CRC_PADDED 0x02
+
+
+#define MY_USB_DEVICE(vend,prod,dc,ic,isc) \
+ .match_flags = USB_DEVICE_ID_MATCH_DEVICE | USB_DEVICE_ID_MATCH_DEV_CLASS | \
+ USB_DEVICE_ID_MATCH_INT_CLASS | USB_DEVICE_ID_MATCH_INT_SUBCLASS, \
+ .idVendor = (vend), \
+ .idProduct = (prod),\
+ .bDeviceClass = (dc),\
+ .bInterfaceClass = (ic), \
+ .bInterfaceSubClass = (isc),
+
+static struct usb_device_id id_table[] = {
+ {MY_USB_DEVICE (0x49f, 0xffff, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, // Itsy
+ {MY_USB_DEVICE (0x3f0, 0x2101, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, // Calypso
+ {MY_USB_DEVICE (0x4dd, 0x8001, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, // Iris
+ {MY_USB_DEVICE (0x4dd, 0x8002, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, // Collie
+ {MY_USB_DEVICE (0x4dd, 0x8003, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, // Collie
+ {MY_USB_DEVICE (0x4dd, 0x8004, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, // Collie
+ {MY_USB_DEVICE (0x5f9, 0xffff, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)}, // Sharp tmp
+#if defined(CONFIG_USB_SAFE_SERIAL_VENDOR)
+ {MY_USB_DEVICE
+ (CONFIG_USB_SAFE_SERIAL_VENDOR, CONFIG_USB_SAFE_SERIAL_PRODUCT, CDC_DEVICE_CLASS,
+ LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)},
+#endif
+ // extra null entry for module
+ // vendor/produc parameters
+ {MY_USB_DEVICE (0, 0, CDC_DEVICE_CLASS, LINEO_INTERFACE_CLASS, LINEO_INTERFACE_SUBCLASS_SAFESERIAL)},
+ {} // terminating entry
+};
+
+MODULE_DEVICE_TABLE (usb, id_table);
+
+static struct usb_driver safe_driver = {
+ .owner = THIS_MODULE,
+ .name = "safe_serial",
+ .probe = usb_serial_probe,
+ .disconnect = usb_serial_disconnect,
+ .id_table = id_table,
+};
+
+static __u16 crc10_table[256] = {
+ 0x000, 0x233, 0x255, 0x066, 0x299, 0x0aa, 0x0cc, 0x2ff, 0x301, 0x132, 0x154, 0x367, 0x198, 0x3ab, 0x3cd, 0x1fe,
+ 0x031, 0x202, 0x264, 0x057, 0x2a8, 0x09b, 0x0fd, 0x2ce, 0x330, 0x103, 0x165, 0x356, 0x1a9, 0x39a, 0x3fc, 0x1cf,
+ 0x062, 0x251, 0x237, 0x004, 0x2fb, 0x0c8, 0x0ae, 0x29d, 0x363, 0x150, 0x136, 0x305, 0x1fa, 0x3c9, 0x3af, 0x19c,
+ 0x053, 0x260, 0x206, 0x035, 0x2ca, 0x0f9, 0x09f, 0x2ac, 0x352, 0x161, 0x107, 0x334, 0x1cb, 0x3f8, 0x39e, 0x1ad,
+ 0x0c4, 0x2f7, 0x291, 0x0a2, 0x25d, 0x06e, 0x008, 0x23b, 0x3c5, 0x1f6, 0x190, 0x3a3, 0x15c, 0x36f, 0x309, 0x13a,
+ 0x0f5, 0x2c6, 0x2a0, 0x093, 0x26c, 0x05f, 0x039, 0x20a, 0x3f4, 0x1c7, 0x1a1, 0x392, 0x16d, 0x35e, 0x338, 0x10b,
+ 0x0a6, 0x295, 0x2f3, 0x0c0, 0x23f, 0x00c, 0x06a, 0x259, 0x3a7, 0x194, 0x1f2, 0x3c1, 0x13e, 0x30d, 0x36b, 0x158,
+ 0x097, 0x2a4, 0x2c2, 0x0f1, 0x20e, 0x03d, 0x05b, 0x268, 0x396, 0x1a5, 0x1c3, 0x3f0, 0x10f, 0x33c, 0x35a, 0x169,
+ 0x188, 0x3bb, 0x3dd, 0x1ee, 0x311, 0x122, 0x144, 0x377, 0x289, 0x0ba, 0x0dc, 0x2ef, 0x010, 0x223, 0x245, 0x076,
+ 0x1b9, 0x38a, 0x3ec, 0x1df, 0x320, 0x113, 0x175, 0x346, 0x2b8, 0x08b, 0x0ed, 0x2de, 0x021, 0x212, 0x274, 0x047,
+ 0x1ea, 0x3d9, 0x3bf, 0x18c, 0x373, 0x140, 0x126, 0x315, 0x2eb, 0x0d8, 0x0be, 0x28d, 0x072, 0x241, 0x227, 0x014,
+ 0x1db, 0x3e8, 0x38e, 0x1bd, 0x342, 0x171, 0x117, 0x324, 0x2da, 0x0e9, 0x08f, 0x2bc, 0x043, 0x270, 0x216, 0x025,
+ 0x14c, 0x37f, 0x319, 0x12a, 0x3d5, 0x1e6, 0x180, 0x3b3, 0x24d, 0x07e, 0x018, 0x22b, 0x0d4, 0x2e7, 0x281, 0x0b2,
+ 0x17d, 0x34e, 0x328, 0x11b, 0x3e4, 0x1d7, 0x1b1, 0x382, 0x27c, 0x04f, 0x029, 0x21a, 0x0e5, 0x2d6, 0x2b0, 0x083,
+ 0x12e, 0x31d, 0x37b, 0x148, 0x3b7, 0x184, 0x1e2, 0x3d1, 0x22f, 0x01c, 0x07a, 0x249, 0x0b6, 0x285, 0x2e3, 0x0d0,
+ 0x11f, 0x32c, 0x34a, 0x179, 0x386, 0x1b5, 0x1d3, 0x3e0, 0x21e, 0x02d, 0x04b, 0x278, 0x087, 0x2b4, 0x2d2, 0x0e1,
+};
+
+#define CRC10_INITFCS 0x000 // Initial FCS value
+#define CRC10_GOODFCS 0x000 // Good final FCS value
+#define CRC10_FCS(fcs, c) ( (((fcs) << 8) & 0x3ff) ^ crc10_table[((fcs) >> 2) & 0xff] ^ (c))
+
+/**
+ * fcs_compute10 - memcpy and calculate 10 bit CRC across buffer
+ * @sp: pointer to buffer
+ * @len: number of bytes
+ * @fcs: starting FCS
+ *
+ * Perform a memcpy and calculate fcs using ppp 10bit CRC algorithm. Return
+ * new 10 bit FCS.
+ */
+static __u16 __inline__ fcs_compute10 (unsigned char *sp, int len, __u16 fcs)
+{
+ for (; len-- > 0; fcs = CRC10_FCS (fcs, *sp++));
+ return fcs;
+}
+
+static void safe_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
+{
+ struct usb_serial_port *port = (struct usb_serial_port *) urb->context;
+ unsigned char *data = urb->transfer_buffer;
+ unsigned char length = urb->actual_length;
+ int i;
+ int result;
+
+ dbg ("%s", __FUNCTION__);
+
+ if (urb->status) {
+ dbg ("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
+ return;
+ }
+
+ dbg ("safe_read_bulk_callback length: %d", port->read_urb->actual_length);
+#ifdef ECHO_RCV
+ {
+ int i;
+ unsigned char *cp = port->read_urb->transfer_buffer;
+ for (i = 0; i < port->read_urb->actual_length; i++) {
+ if ((i % 32) == 0) {
+ printk ("\nru[%02x] ", i);
+ }
+ printk ("%02x ", *cp++);
+ }
+ printk ("\n");
+ }
+#endif
+ if (safe) {
+ __u16 fcs;
+ if (!(fcs = fcs_compute10 (data, length, CRC10_INITFCS))) {
+
+ int actual_length = data[length - 2] >> 2;
+
+ if (actual_length <= (length - 2)) {
+
+ info ("%s - actual: %d", __FUNCTION__, actual_length);
+
+ for (i = 0; i < actual_length; i++) {
+ tty_insert_flip_char (port->tty, data[i], 0);
+ }
+ tty_flip_buffer_push (port->tty);
+ } else {
+ err ("%s - inconsistent lengths %d:%d", __FUNCTION__,
+ actual_length, length);
+ }
+ } else {
+ err ("%s - bad CRC %x", __FUNCTION__, fcs);
+ }
+ } else {
+ for (i = 0; i < length; i++) {
+ tty_insert_flip_char (port->tty, data[i], 0);
+ }
+ tty_flip_buffer_push (port->tty);
+ }
+
+ /* Continue trying to always read */
+ usb_fill_bulk_urb (urb, port->serial->dev,
+ usb_rcvbulkpipe (port->serial->dev, port->bulk_in_endpointAddress),
+ urb->transfer_buffer, urb->transfer_buffer_length,
+ safe_read_bulk_callback, port);
+
+ if ((result = usb_submit_urb (urb, GFP_ATOMIC))) {
+ err ("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
+ }
+}
+
+static int safe_write (struct usb_serial_port *port, const unsigned char *buf, int count)
+{
+ unsigned char *data;
+ int result;
+ int i;
+ int packet_length;
+
+ dbg ("safe_write port: %p %d urb: %p count: %d", port, port->number, port->write_urb,
+ count);
+
+ if (!port->write_urb) {
+ dbg ("%s - write urb NULL", __FUNCTION__);
+ return (0);
+ }
+
+ dbg ("safe_write write_urb: %d transfer_buffer_length",
+ port->write_urb->transfer_buffer_length);
+
+ if (!port->write_urb->transfer_buffer_length) {
+ dbg ("%s - write urb transfer_buffer_length zero", __FUNCTION__);
+ return (0);
+ }
+ if (count == 0) {
+ dbg ("%s - write request of 0 bytes", __FUNCTION__);
+ return (0);
+ }
+ if (port->write_urb->status == -EINPROGRESS) {
+ dbg ("%s - already writing", __FUNCTION__);
+ return (0);
+ }
+
+ packet_length = port->bulk_out_size; // get max packetsize
+
+ i = packet_length - (safe ? 2 : 0); // get bytes to send
+ count = (count > i) ? i : count;
+
+
+ // get the data into the transfer buffer
+ data = port->write_urb->transfer_buffer;
+ memset (data, '0', packet_length);
+
+ memcpy (data, buf, count);
+
+ if (safe) {
+ __u16 fcs;
+
+ // pad if necessary
+ if (!padded) {
+ packet_length = count + 2;
+ }
+ // set count
+ data[packet_length - 2] = count << 2;
+ data[packet_length - 1] = 0;
+
+ // compute fcs and insert into trailer
+ fcs = fcs_compute10 (data, packet_length, CRC10_INITFCS);
+ data[packet_length - 2] |= fcs >> 8;
+ data[packet_length - 1] |= fcs & 0xff;
+
+ // set length to send
+ port->write_urb->transfer_buffer_length = packet_length;
+ } else {
+ port->write_urb->transfer_buffer_length = count;
+ }
+
+ usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count, port->write_urb->transfer_buffer);
+#ifdef ECHO_TX
+ {
+ int i;
+ unsigned char *cp = port->write_urb->transfer_buffer;
+ for (i = 0; i < port->write_urb->transfer_buffer_length; i++) {
+ if ((i % 32) == 0) {
+ printk ("\nsu[%02x] ", i);
+ }
+ printk ("%02x ", *cp++);
+ }
+ printk ("\n");
+ }
+#endif
+ port->write_urb->dev = port->serial->dev;
+ if ((result = usb_submit_urb (port->write_urb, GFP_KERNEL))) {
+ err ("%s - failed submitting write urb, error %d", __FUNCTION__, result);
+ return 0;
+ }
+ dbg ("%s urb: %p submitted", __FUNCTION__, port->write_urb);
+
+ return (count);
+}
+
+static int safe_write_room (struct usb_serial_port *port)
+{
+ int room = 0; // Default: no room
+
+ dbg ("%s", __FUNCTION__);
+
+ if (port->write_urb->status != -EINPROGRESS)
+ room = port->bulk_out_size - (safe ? 2 : 0);
+
+ if (room) {
+ dbg ("safe_write_room returns %d", room);
+ }
+
+ return (room);
+}
+
+static int safe_startup (struct usb_serial *serial)
+{
+ switch (serial->interface->cur_altsetting->desc.bInterfaceProtocol) {
+ case LINEO_SAFESERIAL_CRC:
+ break;
+ case LINEO_SAFESERIAL_CRC_PADDED:
+ padded = 1;
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static struct usb_serial_device_type safe_device = {
+ .owner = THIS_MODULE,
+ .name = "Safe",
+ .id_table = id_table,
+ .num_interrupt_in = NUM_DONT_CARE,
+ .num_bulk_in = NUM_DONT_CARE,
+ .num_bulk_out = NUM_DONT_CARE,
+ .num_ports = 1,
+ .write = safe_write,
+ .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);