drivers/usb/serial/navman.c

   1 /*
   2  * Navman Serial USB driver
   3  *
   4  * Copyright (C) 2006 Greg Kroah-Hartman <gregkh@suse.de>
   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
   8  *      version 2 as published by the Free Software Foundation.
   9  */
  10
  11 #include <linux/kernel.h>
  12 #include <linux/init.h>
  13 #include <linux/tty.h>
  14 #include <linux/tty_flip.h>
  15 #include <linux/module.h>
  16 #include <linux/usb.h>
  17 #include <linux/usb/serial.h>
  18
  19 static int debug;
  20
  21 static struct usb_device_id id_table [] = {
  22         { USB_DEVICE(0x0a99, 0x0001) }, /* Talon Technology device */
  23         { },
  24 };
  25 MODULE_DEVICE_TABLE(usb, id_table);
  26
  27 static struct usb_driver navman_driver = {
  28         .name =         "navman",
  29         .probe =        usb_serial_probe,
  30         .disconnect =   usb_serial_disconnect,
  31         .id_table =     id_table,
  32         .no_dynamic_id =        1,
  33 };
  34
  35 static void navman_read_int_callback(struct urb *urb)
  36 {
  37         struct usb_serial_port *port = urb->context;
  38         unsigned char *data = urb->transfer_buffer;
  39         struct tty_struct *tty;
  40         int status = urb->status;
  41         int result;
  42
  43         switch (status) {
  44         case 0:
  45                 /* success */
  46                 break;
  47         case -ECONNRESET:
  48         case -ENOENT:
  49         case -ESHUTDOWN:
  50                 /* this urb is terminated, clean up */
  51                 dbg("%s - urb shutting down with status: %d",
  52                     __func__, status);
  53                 return;
  54         default:
  55                 dbg("%s - nonzero urb status received: %d",
  56                     __func__, status);
  57                 goto exit;
  58         }
  59
  60         usb_serial_debug_data(debug, &port->dev, __func__,
  61                               urb->actual_length, data);
  62
  63         tty = port->tty;
  64         if (tty && urb->actual_length) {
  65                 tty_buffer_request_room(tty, urb->actual_length);
  66                 tty_insert_flip_string(tty, data, urb->actual_length);
  67                 tty_flip_buffer_push(tty);
  68         }
  69
  70 exit:
  71         result = usb_submit_urb(urb, GFP_ATOMIC);
  72         if (result)
  73                 dev_err(&urb->dev->dev,
  74                         "%s - Error %d submitting interrupt urb\n",
  75                         __func__, result);
  76 }
  77
  78 static int navman_open(struct usb_serial_port *port, struct file *filp)
  79 {
  80         int result = 0;
  81
  82         dbg("%s - port %d", __func__, port->number);
  83
  84         if (port->interrupt_in_urb) {
  85                 dbg("%s - adding interrupt input for treo", __func__);
  86                 result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
  87                 if (result)
  88                         dev_err(&port->dev,
  89                                 "%s - failed submitting interrupt urb, error %d\n",
  90                                 __func__, result);
  91         }
  92         return result;
  93 }
  94
  95 static void navman_close(struct usb_serial_port *port, struct file *filp)
  96 {
  97         dbg("%s - port %d", __func__, port->number);
  98
  99         usb_kill_urb(port->interrupt_in_urb);
 100 }
 101
 102 static int navman_write(struct usb_serial_port *port,
 103                         const unsigned char *buf, int count)
 104 {
 105         dbg("%s - port %d", __func__, port->number);
 106
 107         /*
 108          * This device can't write any data, only read from the device
 109          * so we just silently eat all data sent to us and say it was
 110          * successfully sent.
 111          * Evil, I know, but do you have a better idea?
 112          */
 113
 114         return count;
 115 }
 116
 117 static struct usb_serial_driver navman_device = {
 118         .driver = {
 119                 .owner =        THIS_MODULE,
 120                 .name =         "navman",
 121         },
 122         .id_table =             id_table,
 123         .usb_driver =           &navman_driver,
 124         .num_ports =            1,
 125         .open =                 navman_open,
 126         .close =                navman_close,
 127         .write =                navman_write,
 128         .read_int_callback =    navman_read_int_callback,
 129 };
 130
 131 static int __init navman_init(void)
 132 {
 133         int retval;
 134
 135         retval = usb_serial_register(&navman_device);
 136         if (retval)
 137                 return retval;
 138         retval = usb_register(&navman_driver);
 139         if (retval)
 140                 usb_serial_deregister(&navman_device);
 141         return retval;
 142 }
 143
 144 static void __exit navman_exit(void)
 145 {
 146         usb_deregister(&navman_driver);
 147         usb_serial_deregister(&navman_device);
 148 }
 149
 150 module_init(navman_init);
 151 module_exit(navman_exit);
 152 MODULE_LICENSE("GPL");
 153
 154 module_param(debug, bool, S_IRUGO | S_IWUSR);
 155 MODULE_PARM_DESC(debug, "Debug enabled or not");