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