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/usb.h>
  20
  21 #ifdef CONFIG_USB_SERIAL_DEBUG
  22         static int debug = 1;
  23 #else
  24         static int debug;
  25 #endif
  26
  27 #include "usb-serial.h"
  28
  29
  30 #ifdef CONFIG_USB_SERIAL_GENERIC
  31 static __u16 vendor  = 0x05f9;
  32 static __u16 product = 0xffff;
  33
  34 MODULE_PARM(vendor, "h");
  35 MODULE_PARM_DESC(vendor, "User specified USB idVendor");
  36
  37 MODULE_PARM(product, "h");
  38 MODULE_PARM_DESC(product, "User specified USB idProduct");
  39
  40 static struct usb_device_id generic_device_ids[2]; /* Initially all zeroes. */
  41
  42 /* All of the device info needed for the Generic Serial Converter */
  43 struct usb_serial_device_type usb_serial_generic_device = {
  44         .owner =                THIS_MODULE,
  45         .name =                 "Generic",
  46         .short_name =           "generic",
  47         .id_table =             generic_device_ids,
  48         .num_interrupt_in =     NUM_DONT_CARE,
  49         .num_bulk_in =          NUM_DONT_CARE,
  50         .num_bulk_out =         NUM_DONT_CARE,
  51         .num_ports =            1,
  52         .shutdown =             usb_serial_generic_shutdown,
  53 };
  54 #endif
  55
  56 int usb_serial_generic_register (int _debug)
  57 {
  58         int retval = 0;
  59
  60         debug = _debug;
  61 #ifdef CONFIG_USB_SERIAL_GENERIC
  62         generic_device_ids[0].idVendor = vendor;
  63         generic_device_ids[0].idProduct = product;
  64         generic_device_ids[0].match_flags = USB_DEVICE_ID_MATCH_VENDOR | USB_DEVICE_ID_MATCH_PRODUCT;
  65
  66         /* register our generic driver with ourselves */
  67         retval = usb_serial_register (&usb_serial_generic_device);
  68 #endif
  69         return retval;
  70 }
  71
  72 void usb_serial_generic_deregister (void)
  73 {
  74 #ifdef CONFIG_USB_SERIAL_GENERIC
  75         /* remove our generic driver */
  76         usb_serial_deregister (&usb_serial_generic_device);
  77 #endif
  78 }
  79
  80 int usb_serial_generic_open (struct usb_serial_port *port, struct file *filp)
  81 {
  82         struct usb_serial *serial = port->serial;
  83         int result = 0;
  84
  85         if (port_paranoia_check (port, __FUNCTION__))
  86                 return -ENODEV;
  87
  88         dbg("%s - port %d", __FUNCTION__, port->number);
  89
  90         /* force low_latency on so that our tty_push actually forces the data through,
  91            otherwise it is scheduled, and with high data rates (like with OHCI) data
  92            can get lost. */
  93         if (port->tty)
  94                 port->tty->low_latency = 1;
  95
  96         /* if we have a bulk interrupt, start reading from it */
  97         if (serial->num_bulk_in) {
  98                 /* Start reading from the device */
  99                 usb_fill_bulk_urb (port->read_urb, serial->dev,
 100                                    usb_rcvbulkpipe(serial->dev, port->bulk_in_endpointAddress),
 101                                    port->read_urb->transfer_buffer,
 102                                    port->read_urb->transfer_buffer_length,
 103                                    ((serial->type->read_bulk_callback) ?
 104                                      serial->type->read_bulk_callback :
 105                                      usb_serial_generic_read_bulk_callback),
 106                                    port);
 107                 result = usb_submit_urb(port->read_urb, GFP_KERNEL);
 108                 if (result)
 109                         dev_err(&port->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
 110         }
 111
 112         return result;
 113 }
 114
 115 static void generic_cleanup (struct usb_serial_port *port)
 116 {
 117         struct usb_serial *serial = port->serial;
 118
 119         dbg("%s - port %d", __FUNCTION__, port->number);
 120
 121         if (serial->dev) {
 122                 /* shutdown any bulk reads that might be going on */
 123                 if (serial->num_bulk_out)
 124                         usb_unlink_urb (port->write_urb);
 125                 if (serial->num_bulk_in)
 126                         usb_unlink_urb (port->read_urb);
 127         }
 128 }
 129
 130 void usb_serial_generic_close (struct usb_serial_port *port, struct file * filp)
 131 {
 132         dbg("%s - port %d", __FUNCTION__, port->number);
 133         generic_cleanup (port);
 134 }
 135
 136 int usb_serial_generic_write (struct usb_serial_port *port, int from_user, const unsigned char *buf, int count)
 137 {
 138         struct usb_serial *serial = port->serial;
 139         int result;
 140
 141         dbg("%s - port %d", __FUNCTION__, port->number);
 142
 143         if (count == 0) {
 144                 dbg("%s - write request of 0 bytes", __FUNCTION__);
 145                 return (0);
 146         }
 147
 148         /* only do something if we have a bulk out endpoint */
 149         if (serial->num_bulk_out) {
 150                 if (port->write_urb->status == -EINPROGRESS) {
 151                         dbg("%s - already writing", __FUNCTION__);
 152                         return (0);
 153                 }
 154
 155                 count = (count > port->bulk_out_size) ? port->bulk_out_size : count;
 156
 157                 if (from_user) {
 158                         if (copy_from_user(port->write_urb->transfer_buffer, buf, count))
 159                                 return -EFAULT;
 160                 }
 161                 else {
 162                         memcpy (port->write_urb->transfer_buffer, buf, count);
 163                 }
 164
 165                 usb_serial_debug_data (__FILE__, __FUNCTION__, count, port->write_urb->transfer_buffer);
 166
 167                 /* set up our urb */
 168                 usb_fill_bulk_urb (port->write_urb, serial->dev,
 169                                    usb_sndbulkpipe (serial->dev,
 170                                                     port->bulk_out_endpointAddress),
 171                                    port->write_urb->transfer_buffer, count,
 172                                    ((serial->type->write_bulk_callback) ?
 173                                      serial->type->write_bulk_callback :
 174                                      usb_serial_generic_write_bulk_callback), port);
 175
 176                 /* send the data out the bulk port */
 177                 result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
 178                 if (result)
 179                         dev_err(&port->dev, "%s - failed submitting write urb, error %d\n", __FUNCTION__, result);
 180                 else
 181                         result = count;
 182
 183                 return result;
 184         }
 185
 186         /* no bulk out, so return 0 bytes written */
 187         return (0);
 188 }
 189
 190 int usb_serial_generic_write_room (struct usb_serial_port *port)
 191 {
 192         struct usb_serial *serial = port->serial;
 193         int room = 0;
 194
 195         dbg("%s - port %d", __FUNCTION__, port->number);
 196
 197         if (serial->num_bulk_out) {
 198                 if (port->write_urb->status != -EINPROGRESS)
 199                         room = port->bulk_out_size;
 200         }
 201
 202         dbg("%s - returns %d", __FUNCTION__, room);
 203         return (room);
 204 }
 205
 206 int usb_serial_generic_chars_in_buffer (struct usb_serial_port *port)
 207 {
 208         struct usb_serial *serial = port->serial;
 209         int chars = 0;
 210
 211         dbg("%s - port %d", __FUNCTION__, port->number);
 212
 213         if (serial->num_bulk_out) {
 214                 if (port->write_urb->status == -EINPROGRESS)
 215                         chars = port->write_urb->transfer_buffer_length;
 216         }
 217
 218         dbg("%s - returns %d", __FUNCTION__, chars);
 219         return (chars);
 220 }
 221
 222 void usb_serial_generic_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
 223 {
 224         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
 225         struct usb_serial *serial = get_usb_serial (port, __FUNCTION__);
 226         struct tty_struct *tty;
 227         unsigned char *data = urb->transfer_buffer;
 228         int i;
 229         int result;
 230
 231         dbg("%s - port %d", __FUNCTION__, port->number);
 232
 233         if (!serial) {
 234                 dbg("%s - bad serial pointer, exiting", __FUNCTION__);
 235                 return;
 236         }
 237
 238         if (urb->status) {
 239                 dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
 240                 return;
 241         }
 242
 243         usb_serial_debug_data (__FILE__, __FUNCTION__, urb->actual_length, data);
 244
 245         tty = port->tty;
 246         if (tty && urb->actual_length) {
 247                 for (i = 0; i < urb->actual_length ; ++i) {
 248                         /* if we insert more than TTY_FLIPBUF_SIZE characters, we drop them. */
 249                         if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
 250                                 tty_flip_buffer_push(tty);
 251                         }
 252                         /* this doesn't actually push the data through unless tty->low_latency is set */
 253                         tty_insert_flip_char(tty, data[i], 0);
 254                 }
 255                 tty_flip_buffer_push(tty);
 256         }
 257
 258         /* Continue trying to always read  */
 259         usb_fill_bulk_urb (port->read_urb, serial->dev,
 260                            usb_rcvbulkpipe (serial->dev,
 261                                             port->bulk_in_endpointAddress),
 262                            port->read_urb->transfer_buffer,
 263                            port->read_urb->transfer_buffer_length,
 264                            ((serial->type->read_bulk_callback) ?
 265                              serial->type->read_bulk_callback :
 266                              usb_serial_generic_read_bulk_callback), port);
 267         result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 268         if (result)
 269                 dev_err(&port->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
 270 }
 271
 272 void usb_serial_generic_write_bulk_callback (struct urb *urb, struct pt_regs *regs)
 273 {
 274         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
 275         struct usb_serial *serial = get_usb_serial (port, __FUNCTION__);
 276
 277         dbg("%s - port %d", __FUNCTION__, port->number);
 278
 279         if (!serial) {
 280                 dbg("%s - bad serial pointer, exiting", __FUNCTION__);
 281                 return;
 282         }
 283
 284         if (urb->status) {
 285                 dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
 286                 return;
 287         }
 288
 289         usb_serial_port_softint((void *)port);
 290
 291         schedule_work(&port->work);
 292 }
 293
 294 void usb_serial_generic_shutdown (struct usb_serial *serial)
 295 {
 296         int i;
 297
 298         dbg("%s", __FUNCTION__);
 299
 300         /* stop reads and writes on all ports */
 301         for (i=0; i < serial->num_ports; ++i) {
 302                 generic_cleanup (&serial->port[i]);
 303         }
 304 }
 305