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 
ezusb_writememory(struct usb_serial * serial,int address,unsigned char * data,int length,__u8 request)23 int ezusb_writememory(struct usb_serial *serial, int address,
24 				unsigned char *data, int length, __u8 request)
25 {
26 	int result;
27 	unsigned char *transfer_buffer;
28 
29 	/* dbg("ezusb_writememory %x, %d", address, length); */
30 	if (!serial->dev) {
31 		printk(KERN_ERR "ezusb: %s - no physical device present, "
32 		       "failing.\n", __func__);
33 		return -ENODEV;
34 	}
35 
36 	transfer_buffer = kmemdup(data, length, GFP_KERNEL);
37 	if (!transfer_buffer) {
38 		dev_err(&serial->dev->dev, "%s - kmalloc(%d) failed.\n",
39 							__func__, length);
40 		return -ENOMEM;
41 	}
42 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
43 		     request, 0x40, address, 0, transfer_buffer, length, 3000);
44 	kfree(transfer_buffer);
45 	return result;
46 }
47 EXPORT_SYMBOL_GPL(ezusb_writememory);
48 
ezusb_set_reset(struct usb_serial * serial,unsigned char reset_bit)49 int ezusb_set_reset(struct usb_serial *serial, unsigned char reset_bit)
50 {
51 	int response;
52 
53 	/* dbg("%s - %d", __func__, reset_bit); */
54 	response = ezusb_writememory(serial, CPUCS_REG, &reset_bit, 1, 0xa0);
55 	if (response < 0)
56 		dev_err(&serial->dev->dev, "%s- %d failed\n",
57 						__func__, reset_bit);
58 	return response;
59 }
60 EXPORT_SYMBOL_GPL(ezusb_set_reset);
61 
62