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