aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/usb/misc/cypress_cy7c63.c
blob: 1547d8cac5fb96fcae8f87b0085a63c277eb1320 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
/*
* cypress_cy7c63.c
*
* Copyright (c) 2006-2007 Oliver Bock (bock@tfh-berlin.de)
*
*	This driver is based on the Cypress USB Driver by Marcus Maul
*	(cyport) and the 2.0 version of Greg Kroah-Hartman's
*	USB Skeleton driver.
*
*	This is a generic driver for the Cypress CY7C63xxx family.
*	For the time being it enables you to read from and write to
*	the single I/O ports of the device.
*
*	Supported vendors:	AK Modul-Bus Computer GmbH
*				(Firmware "Port-Chip")
*
*	Supported devices:	CY7C63001A-PC
*				CY7C63001C-PXC
*				CY7C63001C-SXC
*
*	Supported functions:	Read/Write Ports
*
*
*	For up-to-date information please visit:
*	http://www.obock.de/kernel/cypress
*
*	This program is free software; you can redistribute it and/or
*	modify it under the terms of the GNU General Public License as
*	published by the Free Software Foundation, version 2.
*/

#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/usb.h>

#define DRIVER_AUTHOR		"Oliver Bock (bock@tfh-berlin.de)"
#define DRIVER_DESC		"Cypress CY7C63xxx USB driver"

#define CYPRESS_VENDOR_ID	0xa2c
#define CYPRESS_PRODUCT_ID	0x8

#define CYPRESS_READ_PORT	0x4
#define CYPRESS_WRITE_PORT	0x5

#define CYPRESS_READ_RAM	0x2
#define CYPRESS_WRITE_RAM	0x3
#define CYPRESS_READ_ROM	0x1

#define CYPRESS_READ_PORT_ID0	0
#define CYPRESS_WRITE_PORT_ID0	0
#define CYPRESS_READ_PORT_ID1	0x2
#define CYPRESS_WRITE_PORT_ID1	1

#define CYPRESS_MAX_REQSIZE	8


/* table of devices that work with this driver */
static const struct usb_device_id cypress_table[] = {
	{ USB_DEVICE(CYPRESS_VENDOR_ID, CYPRESS_PRODUCT_ID) },
	{ }
};
MODULE_DEVICE_TABLE(usb, cypress_table);

/* structure to hold all of our device specific stuff */
struct cypress {
	struct usb_device *	udev;
	unsigned char		port[2];
};

/* used to send usb control messages to device */
static int vendor_command(struct cypress *dev, unsigned char request,
			  unsigned char address, unsigned char data)
{
	int retval = 0;
	unsigned int pipe;
	unsigned char *iobuf;

	/* allocate some memory for the i/o buffer*/
	iobuf = kzalloc(CYPRESS_MAX_REQSIZE, GFP_KERNEL);
	if (!iobuf) {
		dev_err(&dev->udev->dev, "Out of memory!\n");
		retval = -ENOMEM;
		goto error;
	}

	dev_dbg(&dev->udev->dev, "Sending usb_control_msg (data: %d)\n", data);

	/* prepare usb control message and send it upstream */
	pipe = usb_rcvctrlpipe(dev->udev, 0);
	retval = usb_control_msg(dev->udev, pipe, request,
				 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_OTHER,
				 address, data, iobuf, CYPRESS_MAX_REQSIZE,
				 USB_CTRL_GET_TIMEOUT);

	/* store returned data (more READs to be added) */
	switch (request) {
		case CYPRESS_READ_PORT:
			if (address == CYPRESS_READ_PORT_ID0) {
				dev->port[0] = iobuf[1];
				dev_dbg(&dev->udev->dev,
					"READ_PORT0 returned: %d\n",
					dev->port[0]);
			}
			else if (address == CYPRESS_READ_PORT_ID1) {
				dev->port[1] = iobuf[1];
				dev_dbg(&dev->udev->dev,
					"READ_PORT1 returned: %d\n",
					dev->port[1]);
			}
			break;
	}

	kfree(iobuf);
error:
	return retval;
}

/* write port value */
static ssize_t write_port(struct device *dev, struct device_attribute *attr,
			  const char *buf, size_t count,
			  int port_num, int write_id)
{
	int value = -1;
	int result = 0;

	struct usb_interface *intf = to_usb_interface(dev);
	struct cypress *cyp = usb_get_intfdata(intf);

	dev_dbg(&cyp->udev->dev, "WRITE_PORT%d called\n", port_num);

	/* validate input data */
	if (sscanf(buf, "%d", &value) < 1) {
		result = -EINVAL;
		goto error;
	}
	if (value < 0 || value > 255) {
		result = -EINVAL;
		goto error;
	}

	result = vendor_command(cyp, CYPRESS_WRITE_PORT, write_id,
				(unsigned char)value);

	dev_dbg(&cyp->udev->dev, "Result of vendor_command: %d\n\n", result);
error:
	return result < 0 ? result : count;
}

/* attribute callback handler (write) */
static ssize_t set_port0_handler(struct device *dev,
				 struct device_attribute *attr,
				 const char *buf, size_t count)
{
	return write_port(dev, attr, buf, count, 0, CYPRESS_WRITE_PORT_ID0);
}

/* attribute callback handler (write) */
static ssize_t set_port1_handler(struct device *dev,
				 struct device_attribute *attr,
				 const char *buf, size_t count)
{
	return write_port(dev, attr, buf, count, 1, CYPRESS_WRITE_PORT_ID1);
}

/* read port value */
static ssize_t read_port(struct device *dev, struct device_attribute *attr,
			 char *buf, int port_num, int read_id)
{
	int result = 0;

	struct usb_interface *intf = to_usb_interface(dev);
	struct cypress *cyp = usb_get_intfdata(intf);

	dev_dbg(&cyp->udev->dev, "READ_PORT%d called\n", port_num);

	result = vendor_command(cyp, CYPRESS_READ_PORT, read_id, 0);

	dev_dbg(&cyp->udev->dev, "Result of vendor_command: %d\n\n", result);

	return sprintf(buf, "%d", cyp->port[port_num]);
}

/* attribute callback handler (read) */
static ssize_t get_port0_handler(struct device *dev,
				 struct device_attribute *attr, char *buf)
{
	return read_port(dev, attr, buf, 0, CYPRESS_READ_PORT_ID0);
}

/* attribute callback handler (read) */
static ssize_t get_port1_handler(struct device *dev,
				 struct device_attribute *attr, char *buf)
{
	return read_port(dev, attr, buf, 1, CYPRESS_READ_PORT_ID1);
}

static DEVICE_ATTR(port0, S_IWUGO | S_IRUGO,
		   get_port0_handler, set_port0_handler);

static DEVICE_ATTR(port1, S_IWUGO | S_IRUGO,
		   get_port1_handler, set_port1_handler);


static int cypress_probe(struct usb_interface *interface,
			 const struct usb_device_id *id)
{
	struct cypress *dev = NULL;
	int retval = -ENOMEM;

	/* allocate memory for our device state and initialize it */
	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
	if (dev == NULL) {
		dev_err(&interface->dev, "Out of memory!\n");
		goto error_mem;
	}

	dev->udev = usb_get_dev(interface_to_usbdev(interface));

	/* save our data pointer in this interface device */
	usb_set_intfdata(interface, dev);

	/* create device attribute files */
	retval = device_create_file(&interface->dev, &dev_attr_port0);
	if (retval)
		goto error;
	retval = device_create_file(&interface->dev, &dev_attr_port1);
	if (retval)
		goto error;

	/* let the user know that the device is now attached */
	dev_info(&interface->dev,
		 "Cypress CY7C63xxx device now attached\n");
	return 0;

error:
	device_remove_file(&interface->dev, &dev_attr_port0);
	device_remove_file(&interface->dev, &dev_attr_port1);
	usb_set_intfdata(interface, NULL);
	usb_put_dev(dev->udev);
	kfree(dev);

error_mem:
	return retval;
}

static void cypress_disconnect(struct usb_interface *interface)
{
	struct cypress *dev;

	dev = usb_get_intfdata(interface);

	/* remove device attribute files */
	device_remove_file(&interface->dev, &dev_attr_port0);
	device_remove_file(&interface->dev, &dev_attr_port1);
	/* the intfdata can be set to NULL only after the
	 * device files have been removed */
	usb_set_intfdata(interface, NULL);

	usb_put_dev(dev->udev);

	dev_info(&interface->dev,
		 "Cypress CY7C63xxx device now disconnected\n");

	kfree(dev);
}

static struct usb_driver cypress_driver = {
	.name = "cypress_cy7c63",
	.probe = cypress_probe,
	.disconnect = cypress_disconnect,
	.id_table = cypress_table,
};

static int __init cypress_init(void)
{
	int result;

	/* register this driver with the USB subsystem */
	result = usb_register(&cypress_driver);
	if (result)
		printk(KERN_ERR KBUILD_MODNAME ": usb_register failed! "
		       "Error number: %d\n", result);

	return result;
}

static void __exit cypress_exit(void)
{
	/* deregister this driver with the USB subsystem */
	usb_deregister(&cypress_driver);
}

module_init(cypress_init);
module_exit(cypress_exit);

MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);

MODULE_LICENSE("GPL");