xref: /OK3568_Linux_fs/kernel/drivers/usb/serial/wishbone-serial.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0+
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * USB Wishbone-Serial adapter driver
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * Copyright (C) 2013 Wesley W. Terpstra <w.terpstra@gsi.de>
6*4882a593Smuzhiyun  * Copyright (C) 2013 GSI Helmholtz Centre for Heavy Ion Research GmbH
7*4882a593Smuzhiyun  */
8*4882a593Smuzhiyun 
9*4882a593Smuzhiyun #include <linux/kernel.h>
10*4882a593Smuzhiyun #include <linux/tty.h>
11*4882a593Smuzhiyun #include <linux/module.h>
12*4882a593Smuzhiyun #include <linux/usb.h>
13*4882a593Smuzhiyun #include <linux/usb/serial.h>
14*4882a593Smuzhiyun #include <linux/uaccess.h>
15*4882a593Smuzhiyun 
16*4882a593Smuzhiyun #define GSI_VENDOR_OPENCLOSE 0xB0
17*4882a593Smuzhiyun 
18*4882a593Smuzhiyun static const struct usb_device_id id_table[] = {
19*4882a593Smuzhiyun 	{ USB_DEVICE_AND_INTERFACE_INFO(0x1D50, 0x6062, 0xFF, 0xFF, 0xFF) },
20*4882a593Smuzhiyun 	{ },
21*4882a593Smuzhiyun };
22*4882a593Smuzhiyun MODULE_DEVICE_TABLE(usb, id_table);
23*4882a593Smuzhiyun 
24*4882a593Smuzhiyun /*
25*4882a593Smuzhiyun  * Etherbone must be told that a new stream has begun before data arrives.
26*4882a593Smuzhiyun  * This is necessary to restart the negotiation of Wishbone bus parameters.
27*4882a593Smuzhiyun  * Similarly, when the stream ends, Etherbone must be told so that the cycle
28*4882a593Smuzhiyun  * line can be driven low in the case that userspace failed to do so.
29*4882a593Smuzhiyun  */
usb_gsi_openclose(struct usb_serial_port * port,int value)30*4882a593Smuzhiyun static int usb_gsi_openclose(struct usb_serial_port *port, int value)
31*4882a593Smuzhiyun {
32*4882a593Smuzhiyun 	struct usb_device *dev = port->serial->dev;
33*4882a593Smuzhiyun 
34*4882a593Smuzhiyun 	return usb_control_msg(
35*4882a593Smuzhiyun 		dev,
36*4882a593Smuzhiyun 		usb_sndctrlpipe(dev, 0), /* Send to EP0OUT */
37*4882a593Smuzhiyun 		GSI_VENDOR_OPENCLOSE,
38*4882a593Smuzhiyun 		USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_INTERFACE,
39*4882a593Smuzhiyun 		value, /* wValue = device is open(1) or closed(0) */
40*4882a593Smuzhiyun 		port->serial->interface->cur_altsetting->desc.bInterfaceNumber,
41*4882a593Smuzhiyun 		NULL, 0,  /* There is no data stage */
42*4882a593Smuzhiyun 		5000); /* Timeout till operation fails */
43*4882a593Smuzhiyun }
44*4882a593Smuzhiyun 
wishbone_serial_open(struct tty_struct * tty,struct usb_serial_port * port)45*4882a593Smuzhiyun static int wishbone_serial_open(struct tty_struct *tty,
46*4882a593Smuzhiyun 				struct usb_serial_port *port)
47*4882a593Smuzhiyun {
48*4882a593Smuzhiyun 	int retval;
49*4882a593Smuzhiyun 
50*4882a593Smuzhiyun 	retval = usb_gsi_openclose(port, 1);
51*4882a593Smuzhiyun 	if (retval) {
52*4882a593Smuzhiyun 		dev_err(&port->serial->dev->dev,
53*4882a593Smuzhiyun 		       "Could not mark device as open (%d)\n",
54*4882a593Smuzhiyun 		       retval);
55*4882a593Smuzhiyun 		return retval;
56*4882a593Smuzhiyun 	}
57*4882a593Smuzhiyun 
58*4882a593Smuzhiyun 	retval = usb_serial_generic_open(tty, port);
59*4882a593Smuzhiyun 	if (retval)
60*4882a593Smuzhiyun 		usb_gsi_openclose(port, 0);
61*4882a593Smuzhiyun 
62*4882a593Smuzhiyun 	return retval;
63*4882a593Smuzhiyun }
64*4882a593Smuzhiyun 
wishbone_serial_close(struct usb_serial_port * port)65*4882a593Smuzhiyun static void wishbone_serial_close(struct usb_serial_port *port)
66*4882a593Smuzhiyun {
67*4882a593Smuzhiyun 	usb_serial_generic_close(port);
68*4882a593Smuzhiyun 	usb_gsi_openclose(port, 0);
69*4882a593Smuzhiyun }
70*4882a593Smuzhiyun 
71*4882a593Smuzhiyun static struct usb_serial_driver wishbone_serial_device = {
72*4882a593Smuzhiyun 	.driver = {
73*4882a593Smuzhiyun 		.owner =	THIS_MODULE,
74*4882a593Smuzhiyun 		.name =		"wishbone_serial",
75*4882a593Smuzhiyun 	},
76*4882a593Smuzhiyun 	.id_table =		id_table,
77*4882a593Smuzhiyun 	.num_ports =		1,
78*4882a593Smuzhiyun 	.open =			&wishbone_serial_open,
79*4882a593Smuzhiyun 	.close =		&wishbone_serial_close,
80*4882a593Smuzhiyun };
81*4882a593Smuzhiyun 
82*4882a593Smuzhiyun static struct usb_serial_driver * const serial_drivers[] = {
83*4882a593Smuzhiyun 	&wishbone_serial_device, NULL
84*4882a593Smuzhiyun };
85*4882a593Smuzhiyun 
86*4882a593Smuzhiyun module_usb_serial_driver(serial_drivers, id_table);
87*4882a593Smuzhiyun 
88*4882a593Smuzhiyun MODULE_AUTHOR("Wesley W. Terpstra <w.terpstra@gsi.de>");
89*4882a593Smuzhiyun MODULE_DESCRIPTION("USB Wishbone-Serial adapter");
90*4882a593Smuzhiyun MODULE_LICENSE("GPL");
91