drivers/usb/serial/generic.c

   1 /*
   2  * USB Serial Converter Generic functions
   3  *
   4  * Copyright (C) 1999 - 2002 Greg Kroah-Hartman (greg@kroah.com)
   5  *
   6  *      This program is free software; you can redistribute it and/or
   7  *      modify it under the terms of the GNU General Public License version
   8  *      2 as published by the Free Software Foundation.
   9  *
  10  */
  11
  12 #include <linux/config.h>
  13 #include <linux/kernel.h>
  14 #include <linux/errno.h>
  15 #include <linux/slab.h>
  16 #include <linux/tty.h>
  17 #include <linux/tty_flip.h>
  18 #include <linux/module.h>
  19 #include <linux/moduleparam.h>
  20 #include <linux/usb.h>
  21 #include <asm/uaccess.h>
  22
  23 #ifdef CONFIG_USB_SERIAL_DEBUG
  24         static int debug = 1;
  25 #else
  26         static int debug;
  27 #endif
  28
  29 #include "usb-serial.h"
  30
  31
  32 #ifdef CONFIG_USB_SERIAL_GENERIC
  33 static __u16 vendor  = 0x05f9;
  34 static __u16 product = 0xffff;
  35
  36 module_param(vendor, ushort, 0);
  37 MODULE_PARM_DESC(vendor, "User specified USB idVendor");
  38
  39 module_param(product, ushort, 0);
  40 MODULE_PARM_DESC(product, "User specified USB idProduct");
  41
  42 static struct usb_device_id generic_device_ids[2]; /* Initially all zeroes. */
  43
  44 /* All of the device info needed for the Generic Serial Converter */
  45 struct usb_serial_device_type usb_serial_generic_device = {
  46         .owner =                THIS_MODULE,
  47         .name =                 "Generic",
  48         .short_name =           "generic",
  49         .id_table =             generic_device_ids,
  50         .num_interrupt_in =     NUM_DONT_CARE,
  51         .num_bulk_in =          NUM_DONT_CARE,
  52         .num_bulk_out =         NUM_DONT_CARE,
  53         .num_ports =            1,
  54         .shutdown =             usb_serial_generic_shutdown,
  55 };
  56 #endif
  57
  58 int usb_serial_generic_register (int _debug)
  59 {
  60         int retval = 0;
  61
  62         debug = _debug;
  63 #ifdef CONFIG_USB_SERIAL_GENERIC
  64         generic_device_ids[0].idVendor = vendor;
  65         generic_device_ids[0].idProduct = product;
  66         generic_device_ids[0].match_flags = USB_DEVICE_ID_MATCH_VENDOR | USB_DEVICE_ID_MATCH_PRODUCT;
  67
  68         /* register our generic driver with ourselves */
  69         retval = usb_serial_register (&usb_serial_generic_device);
  70 #endif
  71         return retval;
  72 }
  73
  74 void usb_serial_generic_deregister (void)
  75 {
  76 #ifdef CONFIG_USB_SERIAL_GENERIC
  77         /* remove our generic driver */
  78         usb_serial_deregister (&usb_serial_generic_device);
  79 #endif
  80 }
  81
  82 int usb_serial_generic_open (struct usb_serial_port *port, struct file *filp)
  83 {
  84         struct usb_serial *serial = port->serial;
  85         int result = 0;
  86
  87         dbg("%s - port %d", __FUNCTION__, port->number);
  88
  89         /* force low_latency on so that our tty_push actually forces the data through,
  90            otherwise it is scheduled, and with high data rates (like with OHCI) data
  91            can get lost. */
  92         if (port->tty)
  93                 port->tty->low_latency = 1;
  94
  95         /* if we have a bulk interrupt, start reading from it */
  96         if (serial->num_bulk_in) {
  97                 /* Start reading from the device */
  98                 usb_fill_bulk_urb (port->read_urb, serial->dev,
  99                                    usb_rcvbulkpipe(serial->dev, port->bulk_in_endpointAddress),
 100                                    port->read_urb->transfer_buffer,
 101                                    port->read_urb->transfer_buffer_length,
 102                                    ((serial->type->read_bulk_callback) ?
 103                                      serial->type->read_bulk_callback :
 104                                      usb_serial_generic_read_bulk_callback),
 105                                    port);
 106                 result = usb_submit_urb(port->read_urb, GFP_KERNEL);
 107                 if (result)
 108                         dev_err(&port->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
 109         }
 110
 111         return result;
 112 }
 113
 114 static void generic_cleanup (struct usb_serial_port *port)
 115 {
 116         struct usb_serial *serial = port->serial;
 117
 118         dbg("%s - port %d", __FUNCTION__, port->number);
 119
 120         if (serial->dev) {
 121                 /* shutdown any bulk reads that might be going on */
 122                 if (serial->num_bulk_out)
 123                         usb_unlink_urb (port->write_urb);
 124                 if (serial->num_bulk_in)
 125                         usb_unlink_urb (port->read_urb);
 126         }
 127 }
 128
 129 void usb_serial_generic_close (struct usb_serial_port *port, struct file * filp)
 130 {
 131         dbg("%s - port %d", __FUNCTION__, port->number);
 132         generic_cleanup (port);
 133 }
 134
 135 int usb_serial_generic_write (struct usb_serial_port *port, int from_user, const unsigned char *buf, int count)
 136 {
 137         struct usb_serial *serial = port->serial;
 138         int result;
 139
 140         dbg("%s - port %d", __FUNCTION__, port->number);
 141
 142         if (count == 0) {
 143                 dbg("%s - write request of 0 bytes", __FUNCTION__);
 144                 return (0);
 145         }
 146
 147         /* only do something if we have a bulk out endpoint */
 148         if (serial->num_bulk_out) {
 149                 if (port->write_urb->status == -EINPROGRESS) {
 150                         dbg("%s - already writing", __FUNCTION__);
 151                         return (0);
 152                 }
 153
 154                 count = (count > port->bulk_out_size) ? port->bulk_out_size : count;
 155
 156                 if (from_user) {
 157                         if (copy_from_user(port->write_urb->transfer_buffer, buf, count))
 158                                 return -EFAULT;
 159                 }
 160                 else {
 161                         memcpy (port->write_urb->transfer_buffer, buf, count);
 162                 }
 163
 164                 usb_serial_debug_data (__FILE__, __FUNCTION__, count, port->write_urb->transfer_buffer);
 165
 166                 /* set up our urb */
 167                 usb_fill_bulk_urb (port->write_urb, serial->dev,
 168                                    usb_sndbulkpipe (serial->dev,
 169                                                     port->bulk_out_endpointAddress),
 170                                    port->write_urb->transfer_buffer, count,
 171                                    ((serial->type->write_bulk_callback) ?
 172                                      serial->type->write_bulk_callback :
 173                                      usb_serial_generic_write_bulk_callback), port);
 174
 175                 /* send the data out the bulk port */
 176                 result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
 177                 if (result)
 178                         dev_err(&port->dev, "%s - failed submitting write urb, error %d\n", __FUNCTION__, result);
 179                 else
 180                         result = count;
 181
 182                 return result;
 183         }
 184
 185         /* no bulk out, so return 0 bytes written */
 186         return (0);
 187 }
 188
 189 int usb_serial_generic_write_room (struct usb_serial_port *port)
 190 {
 191         struct usb_serial *serial = port->serial;
 192         int room = 0;
 193
 194         dbg("%s - port %d", __FUNCTION__, port->number);
 195
 196         if (serial->num_bulk_out) {
 197                 if (port->write_urb->status != -EINPROGRESS)
 198                         room = port->bulk_out_size;
 199         }
 200
 201         dbg("%s - returns %d", __FUNCTION__, room);
 202         return (room);
 203 }
 204
 205 int usb_serial_generic_chars_in_buffer (struct usb_serial_port *port)
 206 {
 207         struct usb_serial *serial = port->serial;
 208         int chars = 0;
 209
 210         dbg("%s - port %d", __FUNCTION__, port->number);
 211
 212         if (serial->num_bulk_out) {
 213                 if (port->write_urb->status == -EINPROGRESS)
 214                         chars = port->write_urb->transfer_buffer_length;
 215         }
 216
 217         dbg("%s - returns %d", __FUNCTION__, chars);
 218         return (chars);
 219 }
 220
 221 void usb_serial_generic_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
 222 {
 223         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
 224         struct usb_serial *serial = port->serial;
 225         struct tty_struct *tty;
 226         unsigned char *data = urb->transfer_buffer;
 227         int i;
 228         int result;
 229
 230         dbg("%s - port %d", __FUNCTION__, port->number);
 231
 232         if (urb->status) {
 233                 dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
 234                 return;
 235         }
 236
 237         usb_serial_debug_data (__FILE__, __FUNCTION__, urb->actual_length, data);
 238
 239         tty = port->tty;
 240         if (tty && urb->actual_length) {
 241                 for (i = 0; i < urb->actual_length ; ++i) {
 242                         /* if we insert more than TTY_FLIPBUF_SIZE characters, we drop them. */
 243                         if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
 244                                 tty_flip_buffer_push(tty);
 245                         }
 246                         /* this doesn't actually push the data through unless tty->low_latency is set */
 247                         tty_insert_flip_char(tty, data[i], 0);
 248                 }
 249                 tty_flip_buffer_push(tty);
 250         }
 251
 252         /* Continue trying to always read  */
 253         usb_fill_bulk_urb (port->read_urb, serial->dev,
 254                            usb_rcvbulkpipe (serial->dev,
 255                                             port->bulk_in_endpointAddress),
 256                            port->read_urb->transfer_buffer,
 257                            port->read_urb->transfer_buffer_length,
 258                            ((serial->type->read_bulk_callback) ?
 259                              serial->type->read_bulk_callback :
 260                              usb_serial_generic_read_bulk_callback), port);
 261         result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 262         if (result)
 263                 dev_err(&port->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
 264 }
 265
 266 void usb_serial_generic_write_bulk_callback (struct urb *urb, struct pt_regs *regs)
 267 {
 268         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
 269
 270         dbg("%s - port %d", __FUNCTION__, port->number);
 271
 272         if (urb->status) {
 273                 dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
 274                 return;
 275         }
 276
 277         usb_serial_port_softint((void *)port);
 278
 279         schedule_work(&port->work);
 280 }
 281
 282 void usb_serial_generic_shutdown (struct usb_serial *serial)
 283 {
 284         int i;
 285
 286         dbg("%s", __FUNCTION__);
 287
 288         /* stop reads and writes on all ports */
 289         for (i=0; i < serial->num_ports; ++i) {
 290                 generic_cleanup(serial->port[i]);
 291         }
 292 }
 293