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/kernel.h>
  13 #include <linux/errno.h>
  14 #include <linux/slab.h>
  15 #include <linux/tty.h>
  16 #include <linux/tty_flip.h>
  17 #include <linux/module.h>
  18 #include <linux/moduleparam.h>
  19 #include <linux/usb.h>
  20 #include <linux/usb/serial.h>
  21 #include <asm/uaccess.h>
  22
  23 static int generic_probe(struct usb_interface *interface,
  24                          const struct usb_device_id *id);
  25
  26
  27 static int debug;
  28
  29 #ifdef CONFIG_USB_SERIAL_GENERIC
  30 static __u16 vendor  = 0x05f9;
  31 static __u16 product = 0xffff;
  32
  33 module_param(vendor, ushort, 0);
  34 MODULE_PARM_DESC(vendor, "User specified USB idVendor");
  35
  36 module_param(product, ushort, 0);
  37 MODULE_PARM_DESC(product, "User specified USB idProduct");
  38
  39 static struct usb_device_id generic_device_ids[2]; /* Initially all zeroes. */
  40
  41 /* we want to look at all devices, as the vendor/product id can change
  42  * depending on the command line argument */
  43 static struct usb_device_id generic_serial_ids[] = {
  44         {.driver_info = 42},
  45         {}
  46 };
  47
  48 static struct usb_driver generic_driver = {
  49         .name =         "usbserial_generic",
  50         .probe =        generic_probe,
  51         .disconnect =   usb_serial_disconnect,
  52         .id_table =     generic_serial_ids,
  53         .no_dynamic_id =        1,
  54 };
  55
  56 /* All of the device info needed for the Generic Serial Converter */
  57 struct usb_serial_driver usb_serial_generic_device = {
  58         .driver = {
  59                 .owner =        THIS_MODULE,
  60                 .name =         "generic",
  61         },
  62         .id_table =             generic_device_ids,
  63         .usb_driver =           &generic_driver,
  64         .num_interrupt_in =     NUM_DONT_CARE,
  65         .num_bulk_in =          NUM_DONT_CARE,
  66         .num_bulk_out =         NUM_DONT_CARE,
  67         .num_ports =            1,
  68         .shutdown =             usb_serial_generic_shutdown,
  69 };
  70
  71 static int generic_probe(struct usb_interface *interface,
  72                                const struct usb_device_id *id)
  73 {
  74         const struct usb_device_id *id_pattern;
  75
  76         id_pattern = usb_match_id(interface, generic_device_ids);
  77         if (id_pattern != NULL)
  78                 return usb_serial_probe(interface, id);
  79         return -ENODEV;
  80 }
  81 #endif
  82
  83 int usb_serial_generic_register (int _debug)
  84 {
  85         int retval = 0;
  86
  87         debug = _debug;
  88 #ifdef CONFIG_USB_SERIAL_GENERIC
  89         generic_device_ids[0].idVendor = vendor;
  90         generic_device_ids[0].idProduct = product;
  91         generic_device_ids[0].match_flags = USB_DEVICE_ID_MATCH_VENDOR | USB_DEVICE_ID_MATCH_PRODUCT;
  92
  93         /* register our generic driver with ourselves */
  94         retval = usb_serial_register (&usb_serial_generic_device);
  95         if (retval)
  96                 goto exit;
  97         retval = usb_register(&generic_driver);
  98         if (retval)
  99                 usb_serial_deregister(&usb_serial_generic_device);
 100 exit:
 101 #endif
 102         return retval;
 103 }
 104
 105 void usb_serial_generic_deregister (void)
 106 {
 107 #ifdef CONFIG_USB_SERIAL_GENERIC
 108         /* remove our generic driver */
 109         usb_deregister(&generic_driver);
 110         usb_serial_deregister (&usb_serial_generic_device);
 111 #endif
 112 }
 113
 114 int usb_serial_generic_open (struct usb_serial_port *port, struct file *filp)
 115 {
 116         struct usb_serial *serial = port->serial;
 117         int result = 0;
 118
 119         dbg("%s - port %d", __FUNCTION__, port->number);
 120
 121         /* force low_latency on so that our tty_push actually forces the data through,
 122            otherwise it is scheduled, and with high data rates (like with OHCI) data
 123            can get lost. */
 124         if (port->tty)
 125                 port->tty->low_latency = 1;
 126
 127         /* if we have a bulk interrupt, start reading from it */
 128         if (serial->num_bulk_in) {
 129                 /* Start reading from the device */
 130                 usb_fill_bulk_urb (port->read_urb, serial->dev,
 131                                    usb_rcvbulkpipe(serial->dev, port->bulk_in_endpointAddress),
 132                                    port->read_urb->transfer_buffer,
 133                                    port->read_urb->transfer_buffer_length,
 134                                    ((serial->type->read_bulk_callback) ?
 135                                      serial->type->read_bulk_callback :
 136                                      usb_serial_generic_read_bulk_callback),
 137                                    port);
 138                 result = usb_submit_urb(port->read_urb, GFP_KERNEL);
 139                 if (result)
 140                         dev_err(&port->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
 141         }
 142
 143         return result;
 144 }
 145 EXPORT_SYMBOL_GPL(usb_serial_generic_open);
 146
 147 static void generic_cleanup (struct usb_serial_port *port)
 148 {
 149         struct usb_serial *serial = port->serial;
 150
 151         dbg("%s - port %d", __FUNCTION__, port->number);
 152
 153         if (serial->dev) {
 154                 /* shutdown any bulk reads that might be going on */
 155                 if (serial->num_bulk_out)
 156                         usb_kill_urb(port->write_urb);
 157                 if (serial->num_bulk_in)
 158                         usb_kill_urb(port->read_urb);
 159         }
 160 }
 161
 162 void usb_serial_generic_close (struct usb_serial_port *port, struct file * filp)
 163 {
 164         dbg("%s - port %d", __FUNCTION__, port->number);
 165         generic_cleanup (port);
 166 }
 167
 168 int usb_serial_generic_write(struct usb_serial_port *port, const unsigned char *buf, int count)
 169 {
 170         struct usb_serial *serial = port->serial;
 171         int result;
 172         unsigned char *data;
 173
 174         dbg("%s - port %d", __FUNCTION__, port->number);
 175
 176         if (count == 0) {
 177                 dbg("%s - write request of 0 bytes", __FUNCTION__);
 178                 return (0);
 179         }
 180
 181         /* only do something if we have a bulk out endpoint */
 182         if (serial->num_bulk_out) {
 183                 spin_lock_bh(&port->lock);
 184                 if (port->write_urb_busy) {
 185                         spin_unlock_bh(&port->lock);
 186                         dbg("%s - already writing", __FUNCTION__);
 187                         return 0;
 188                 }
 189                 port->write_urb_busy = 1;
 190                 spin_unlock_bh(&port->lock);
 191
 192                 count = (count > port->bulk_out_size) ? port->bulk_out_size : count;
 193
 194                 memcpy (port->write_urb->transfer_buffer, buf, count);
 195                 data = port->write_urb->transfer_buffer;
 196                 usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count, data);
 197
 198                 /* set up our urb */
 199                 usb_fill_bulk_urb (port->write_urb, serial->dev,
 200                                    usb_sndbulkpipe (serial->dev,
 201                                                     port->bulk_out_endpointAddress),
 202                                    port->write_urb->transfer_buffer, count,
 203                                    ((serial->type->write_bulk_callback) ?
 204                                      serial->type->write_bulk_callback :
 205                                      usb_serial_generic_write_bulk_callback), port);
 206
 207                 /* send the data out the bulk port */
 208                 port->write_urb_busy = 1;
 209                 result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
 210                 if (result) {
 211                         dev_err(&port->dev, "%s - failed submitting write urb, error %d\n", __FUNCTION__, result);
 212                         /* don't have to grab the lock here, as we will retry if != 0 */
 213                         port->write_urb_busy = 0;
 214                 } else
 215                         result = count;
 216
 217                 return result;
 218         }
 219
 220         /* no bulk out, so return 0 bytes written */
 221         return 0;
 222 }
 223
 224 int usb_serial_generic_write_room (struct usb_serial_port *port)
 225 {
 226         struct usb_serial *serial = port->serial;
 227         int room = 0;
 228
 229         dbg("%s - port %d", __FUNCTION__, port->number);
 230
 231         if (serial->num_bulk_out) {
 232                 if (!(port->write_urb_busy))
 233                         room = port->bulk_out_size;
 234         }
 235
 236         dbg("%s - returns %d", __FUNCTION__, room);
 237         return (room);
 238 }
 239
 240 int usb_serial_generic_chars_in_buffer (struct usb_serial_port *port)
 241 {
 242         struct usb_serial *serial = port->serial;
 243         int chars = 0;
 244
 245         dbg("%s - port %d", __FUNCTION__, port->number);
 246
 247         if (serial->num_bulk_out) {
 248                 if (port->write_urb_busy)
 249                         chars = port->write_urb->transfer_buffer_length;
 250         }
 251
 252         dbg("%s - returns %d", __FUNCTION__, chars);
 253         return (chars);
 254 }
 255
 256 void usb_serial_generic_read_bulk_callback (struct urb *urb)
 257 {
 258         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
 259         struct usb_serial *serial = port->serial;
 260         struct tty_struct *tty;
 261         unsigned char *data = urb->transfer_buffer;
 262         int result;
 263
 264         dbg("%s - port %d", __FUNCTION__, port->number);
 265
 266         if (urb->status) {
 267                 dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
 268                 return;
 269         }
 270
 271         usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
 272
 273         tty = port->tty;
 274         if (tty && urb->actual_length) {
 275                 tty_buffer_request_room(tty, urb->actual_length);
 276                 tty_insert_flip_string(tty, data, urb->actual_length);
 277                 tty_flip_buffer_push(tty);
 278         }
 279
 280         /* Continue trying to always read  */
 281         usb_fill_bulk_urb (port->read_urb, serial->dev,
 282                            usb_rcvbulkpipe (serial->dev,
 283                                             port->bulk_in_endpointAddress),
 284                            port->read_urb->transfer_buffer,
 285                            port->read_urb->transfer_buffer_length,
 286                            ((serial->type->read_bulk_callback) ?
 287                              serial->type->read_bulk_callback :
 288                              usb_serial_generic_read_bulk_callback), port);
 289         result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 290         if (result)
 291                 dev_err(&port->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
 292 }
 293 EXPORT_SYMBOL_GPL(usb_serial_generic_read_bulk_callback);
 294
 295 void usb_serial_generic_write_bulk_callback (struct urb *urb)
 296 {
 297         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
 298
 299         dbg("%s - port %d", __FUNCTION__, port->number);
 300
 301         port->write_urb_busy = 0;
 302         if (urb->status) {
 303                 dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
 304                 return;
 305         }
 306
 307         usb_serial_port_softint(port);
 308 }
 309 EXPORT_SYMBOL_GPL(usb_serial_generic_write_bulk_callback);
 310
 311 void usb_serial_generic_shutdown (struct usb_serial *serial)
 312 {
 313         int i;
 314
 315         dbg("%s", __FUNCTION__);
 316
 317         /* stop reads and writes on all ports */
 318         for (i=0; i < serial->num_ports; ++i) {
 319                 generic_cleanup(serial->port[i]);
 320         }
 321 }
 322