drivers/usb/serial/ezusb.c

   1 /*
   2  * EZ-USB specific functions used by some of the USB to Serial drivers.
   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 #include <linux/kernel.h>
  12 #include <linux/errno.h>
  13 #include <linux/init.h>
  14 #include <linux/slab.h>
  15 #include <linux/tty.h>
  16 #include <linux/module.h>
  17 #include <linux/usb.h>
  18 #include <linux/usb/serial.h>
  19
  20 /* EZ-USB Control and Status Register.  Bit 0 controls 8051 reset */
  21 #define CPUCS_REG    0x7F92
  22
  23 int ezusb_writememory (struct usb_serial *serial, int address, unsigned char *data, int length, __u8 bRequest)
  24 {
  25         int result;
  26         unsigned char *transfer_buffer;
  27
  28         /* dbg("ezusb_writememory %x, %d", address, length); */
  29         if (!serial->dev) {
  30                 err("%s - no physical device present, failing.", __FUNCTION__);
  31                 return -ENODEV;
  32         }
  33
  34         transfer_buffer =  kmalloc (length, GFP_KERNEL);
  35         if (!transfer_buffer) {
  36                 dev_err(&serial->dev->dev, "%s - kmalloc(%d) failed.\n", __FUNCTION__, length);
  37                 return -ENOMEM;
  38         }
  39         memcpy (transfer_buffer, data, length);
  40         result = usb_control_msg (serial->dev, usb_sndctrlpipe(serial->dev, 0), bRequest, 0x40, address, 0, transfer_buffer, length, 3000);
  41         kfree (transfer_buffer);
  42         return result;
  43 }
  44
  45 int ezusb_set_reset (struct usb_serial *serial, unsigned char reset_bit)
  46 {
  47         int response;
  48
  49         /* dbg("%s - %d", __FUNCTION__, reset_bit); */
  50         response = ezusb_writememory (serial, CPUCS_REG, &reset_bit, 1, 0xa0);
  51         if (response < 0)
  52                 dev_err(&serial->dev->dev, "%s- %d failed\n", __FUNCTION__, reset_bit);
  53         return response;
  54 }
  55
  56
  57 EXPORT_SYMBOL(ezusb_writememory);
  58 EXPORT_SYMBOL(ezusb_set_reset);
  59