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 #include "usb-serial.h"
  23
  24 static int debug;
  25
  26 #ifdef CONFIG_USB_SERIAL_GENERIC
  27 static __u16 vendor  = 0x05f9;
  28 static __u16 product = 0xffff;
  29
  30 module_param(vendor, ushort, 0);
  31 MODULE_PARM_DESC(vendor, "User specified USB idVendor");
  32
  33 module_param(product, ushort, 0);
  34 MODULE_PARM_DESC(product, "User specified USB idProduct");
  35
  36 static struct usb_device_id generic_device_ids[2]; /* Initially all zeroes. */
  37
  38 /* All of the device info needed for the Generic Serial Converter */
  39 struct usb_serial_device_type usb_serial_generic_device = {
  40         .owner =                THIS_MODULE,
  41         .name =                 "Generic",
  42         .short_name =           "generic",
  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         .owner =        THIS_MODULE,
  71         .name =         "usbserial_generic",
  72         .probe =        generic_probe,
  73         .disconnect =   usb_serial_disconnect,
  74         .id_table =     generic_serial_ids,
  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
 141 static void generic_cleanup (struct usb_serial_port *port)
 142 {
 143         struct usb_serial *serial = port->serial;
 144
 145         dbg("%s - port %d", __FUNCTION__, port->number);
 146
 147         if (serial->dev) {
 148                 /* shutdown any bulk reads that might be going on */
 149                 if (serial->num_bulk_out)
 150                         usb_kill_urb(port->write_urb);
 151                 if (serial->num_bulk_in)
 152                         usb_kill_urb(port->read_urb);
 153         }
 154 }
 155
 156 void usb_serial_generic_close (struct usb_serial_port *port, struct file * filp)
 157 {
 158         dbg("%s - port %d", __FUNCTION__, port->number);
 159         generic_cleanup (port);
 160 }
 161
 162 int usb_serial_generic_write(struct usb_serial_port *port, const unsigned char *buf, int count)
 163 {
 164         struct usb_serial *serial = port->serial;
 165         int result;
 166         unsigned char *data;
 167
 168         dbg("%s - port %d", __FUNCTION__, port->number);
 169
 170         if (count == 0) {
 171                 dbg("%s - write request of 0 bytes", __FUNCTION__);
 172                 return (0);
 173         }
 174
 175         /* only do something if we have a bulk out endpoint */
 176         if (serial->num_bulk_out) {
 177                 spin_lock(&port->lock);
 178                 if (port->write_urb_busy) {
 179                         spin_unlock(&port->lock);
 180                         dbg("%s - already writing", __FUNCTION__);
 181                         return 0;
 182                 }
 183                 port->write_urb_busy = 1;
 184                 spin_unlock(&port->lock);
 185
 186                 count = (count > port->bulk_out_size) ? port->bulk_out_size : count;
 187
 188                 memcpy (port->write_urb->transfer_buffer, buf, count);
 189                 data = port->write_urb->transfer_buffer;
 190                 usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count, data);
 191
 192                 /* set up our urb */
 193                 usb_fill_bulk_urb (port->write_urb, serial->dev,
 194                                    usb_sndbulkpipe (serial->dev,
 195                                                     port->bulk_out_endpointAddress),
 196                                    port->write_urb->transfer_buffer, count,
 197                                    ((serial->type->write_bulk_callback) ?
 198                                      serial->type->write_bulk_callback :
 199                                      usb_serial_generic_write_bulk_callback), port);
 200
 201                 /* send the data out the bulk port */
 202                 port->write_urb_busy = 1;
 203                 result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
 204                 if (result) {
 205                         dev_err(&port->dev, "%s - failed submitting write urb, error %d\n", __FUNCTION__, result);
 206                         /* don't have to grab the lock here, as we will retry if != 0 */
 207                         port->write_urb_busy = 0;
 208                 } else
 209                         result = count;
 210
 211                 return result;
 212         }
 213
 214         /* no bulk out, so return 0 bytes written */
 215         return 0;
 216 }
 217
 218 int usb_serial_generic_write_room (struct usb_serial_port *port)
 219 {
 220         struct usb_serial *serial = port->serial;
 221         int room = 0;
 222
 223         dbg("%s - port %d", __FUNCTION__, port->number);
 224
 225         if (serial->num_bulk_out) {
 226                 if (port->write_urb_busy)
 227                         room = port->bulk_out_size;
 228         }
 229
 230         dbg("%s - returns %d", __FUNCTION__, room);
 231         return (room);
 232 }
 233
 234 int usb_serial_generic_chars_in_buffer (struct usb_serial_port *port)
 235 {
 236         struct usb_serial *serial = port->serial;
 237         int chars = 0;
 238
 239         dbg("%s - port %d", __FUNCTION__, port->number);
 240
 241         if (serial->num_bulk_out) {
 242                 if (port->write_urb_busy)
 243                         chars = port->write_urb->transfer_buffer_length;
 244         }
 245
 246         dbg("%s - returns %d", __FUNCTION__, chars);
 247         return (chars);
 248 }
 249
 250 void usb_serial_generic_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
 251 {
 252         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
 253         struct usb_serial *serial = port->serial;
 254         struct tty_struct *tty;
 255         unsigned char *data = urb->transfer_buffer;
 256         int i;
 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                 for (i = 0; i < urb->actual_length ; ++i) {
 271                         /* if we insert more than TTY_FLIPBUF_SIZE characters, we drop them. */
 272                         if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
 273                                 tty_flip_buffer_push(tty);
 274                         }
 275                         /* this doesn't actually push the data through unless tty->low_latency is set */
 276                         tty_insert_flip_char(tty, data[i], 0);
 277                 }
 278                 tty_flip_buffer_push(tty);
 279         }
 280
 281         /* Continue trying to always read  */
 282         usb_fill_bulk_urb (port->read_urb, serial->dev,
 283                            usb_rcvbulkpipe (serial->dev,
 284                                             port->bulk_in_endpointAddress),
 285                            port->read_urb->transfer_buffer,
 286                            port->read_urb->transfer_buffer_length,
 287                            ((serial->type->read_bulk_callback) ?
 288                              serial->type->read_bulk_callback :
 289                              usb_serial_generic_read_bulk_callback), port);
 290         result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 291         if (result)
 292                 dev_err(&port->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
 293 }
 294
 295 void usb_serial_generic_write_bulk_callback (struct urb *urb, struct pt_regs *regs)
 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((void *)port);
 308
 309         schedule_work(&port->work);
 310 }
 311
 312 void usb_serial_generic_shutdown (struct usb_serial *serial)
 313 {
 314         int i;
 315
 316         dbg("%s", __FUNCTION__);
 317
 318         /* stop reads and writes on all ports */
 319         for (i=0; i < serial->num_ports; ++i) {
 320                 generic_cleanup(serial->port[i]);
 321         }
 322 }
 323