xref: /linux/drivers/usb/misc/cypress_cy7c63.c (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
1 /*
2 * cypress_cy7c63.c
3 *
4 * Copyright (c) 2006-2007 Oliver Bock (bock@tfh-berlin.de)
5 *
6 *	This driver is based on the Cypress USB Driver by Marcus Maul
7 *	(cyport) and the 2.0 version of Greg Kroah-Hartman's
8 *	USB Skeleton driver.
9 *
10 *	This is a generic driver for the Cypress CY7C63xxx family.
11 *	For the time being it enables you to read from and write to
12 *	the single I/O ports of the device.
13 *
14 *	Supported vendors:	AK Modul-Bus Computer GmbH
15 *				(Firmware "Port-Chip")
16 *
17 *	Supported devices:	CY7C63001A-PC
18 *				CY7C63001C-PXC
19 *				CY7C63001C-SXC
20 *
21 *	Supported functions:	Read/Write Ports
22 *
23 *
24 *	For up-to-date information please visit:
25 *	http://www.obock.de/kernel/cypress
26 *
27 *	This program is free software; you can redistribute it and/or
28 *	modify it under the terms of the GNU General Public License as
29 *	published by the Free Software Foundation, version 2.
30 */
31 
32 #include <linux/module.h>
33 #include <linux/kernel.h>
34 #include <linux/slab.h>
35 #include <linux/usb.h>
36 
37 #define DRIVER_AUTHOR		"Oliver Bock (bock@tfh-berlin.de)"
38 #define DRIVER_DESC		"Cypress CY7C63xxx USB driver"
39 
40 #define CYPRESS_VENDOR_ID	0xa2c
41 #define CYPRESS_PRODUCT_ID	0x8
42 
43 #define CYPRESS_READ_PORT	0x4
44 #define CYPRESS_WRITE_PORT	0x5
45 
46 #define CYPRESS_READ_RAM	0x2
47 #define CYPRESS_WRITE_RAM	0x3
48 #define CYPRESS_READ_ROM	0x1
49 
50 #define CYPRESS_READ_PORT_ID0	0
51 #define CYPRESS_WRITE_PORT_ID0	0
52 #define CYPRESS_READ_PORT_ID1	0x2
53 #define CYPRESS_WRITE_PORT_ID1	1
54 
55 #define CYPRESS_MAX_REQSIZE	8
56 
57 
58 /* table of devices that work with this driver */
59 static const struct usb_device_id cypress_table[] = {
60 	{ USB_DEVICE(CYPRESS_VENDOR_ID, CYPRESS_PRODUCT_ID) },
61 	{ }
62 };
63 MODULE_DEVICE_TABLE(usb, cypress_table);
64 
65 /* structure to hold all of our device specific stuff */
66 struct cypress {
67 	struct usb_device *	udev;
68 	unsigned char		port[2];
69 };
70 
71 /* used to send usb control messages to device */
72 static int vendor_command(struct cypress *dev, unsigned char request,
73 			  unsigned char address, unsigned char data)
74 {
75 	int retval = 0;
76 	unsigned int pipe;
77 	unsigned char *iobuf;
78 
79 	/* allocate some memory for the i/o buffer*/
80 	iobuf = kzalloc(CYPRESS_MAX_REQSIZE, GFP_KERNEL);
81 	if (!iobuf) {
82 		retval = -ENOMEM;
83 		goto error;
84 	}
85 
86 	dev_dbg(&dev->udev->dev, "Sending usb_control_msg (data: %d)\n", data);
87 
88 	/* prepare usb control message and send it upstream */
89 	pipe = usb_rcvctrlpipe(dev->udev, 0);
90 	retval = usb_control_msg(dev->udev, pipe, request,
91 				 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_OTHER,
92 				 address, data, iobuf, CYPRESS_MAX_REQSIZE,
93 				 USB_CTRL_GET_TIMEOUT);
94 
95 	/* store returned data (more READs to be added) */
96 	switch (request) {
97 		case CYPRESS_READ_PORT:
98 			if (address == CYPRESS_READ_PORT_ID0) {
99 				dev->port[0] = iobuf[1];
100 				dev_dbg(&dev->udev->dev,
101 					"READ_PORT0 returned: %d\n",
102 					dev->port[0]);
103 			}
104 			else if (address == CYPRESS_READ_PORT_ID1) {
105 				dev->port[1] = iobuf[1];
106 				dev_dbg(&dev->udev->dev,
107 					"READ_PORT1 returned: %d\n",
108 					dev->port[1]);
109 			}
110 			break;
111 	}
112 
113 	kfree(iobuf);
114 error:
115 	return retval;
116 }
117 
118 /* write port value */
119 static ssize_t write_port(struct device *dev, struct device_attribute *attr,
120 			  const char *buf, size_t count,
121 			  int port_num, int write_id)
122 {
123 	int value = -1;
124 	int result = 0;
125 
126 	struct usb_interface *intf = to_usb_interface(dev);
127 	struct cypress *cyp = usb_get_intfdata(intf);
128 
129 	dev_dbg(&cyp->udev->dev, "WRITE_PORT%d called\n", port_num);
130 
131 	/* validate input data */
132 	if (sscanf(buf, "%d", &value) < 1) {
133 		result = -EINVAL;
134 		goto error;
135 	}
136 	if (value < 0 || value > 255) {
137 		result = -EINVAL;
138 		goto error;
139 	}
140 
141 	result = vendor_command(cyp, CYPRESS_WRITE_PORT, write_id,
142 				(unsigned char)value);
143 
144 	dev_dbg(&cyp->udev->dev, "Result of vendor_command: %d\n\n", result);
145 error:
146 	return result < 0 ? result : count;
147 }
148 
149 /* attribute callback handler (write) */
150 static ssize_t set_port0_handler(struct device *dev,
151 				 struct device_attribute *attr,
152 				 const char *buf, size_t count)
153 {
154 	return write_port(dev, attr, buf, count, 0, CYPRESS_WRITE_PORT_ID0);
155 }
156 
157 /* attribute callback handler (write) */
158 static ssize_t set_port1_handler(struct device *dev,
159 				 struct device_attribute *attr,
160 				 const char *buf, size_t count)
161 {
162 	return write_port(dev, attr, buf, count, 1, CYPRESS_WRITE_PORT_ID1);
163 }
164 
165 /* read port value */
166 static ssize_t read_port(struct device *dev, struct device_attribute *attr,
167 			 char *buf, int port_num, int read_id)
168 {
169 	int result = 0;
170 
171 	struct usb_interface *intf = to_usb_interface(dev);
172 	struct cypress *cyp = usb_get_intfdata(intf);
173 
174 	dev_dbg(&cyp->udev->dev, "READ_PORT%d called\n", port_num);
175 
176 	result = vendor_command(cyp, CYPRESS_READ_PORT, read_id, 0);
177 
178 	dev_dbg(&cyp->udev->dev, "Result of vendor_command: %d\n\n", result);
179 
180 	return sprintf(buf, "%d", cyp->port[port_num]);
181 }
182 
183 /* attribute callback handler (read) */
184 static ssize_t get_port0_handler(struct device *dev,
185 				 struct device_attribute *attr, char *buf)
186 {
187 	return read_port(dev, attr, buf, 0, CYPRESS_READ_PORT_ID0);
188 }
189 
190 /* attribute callback handler (read) */
191 static ssize_t get_port1_handler(struct device *dev,
192 				 struct device_attribute *attr, char *buf)
193 {
194 	return read_port(dev, attr, buf, 1, CYPRESS_READ_PORT_ID1);
195 }
196 
197 static DEVICE_ATTR(port0, S_IRUGO | S_IWUSR, get_port0_handler, set_port0_handler);
198 
199 static DEVICE_ATTR(port1, S_IRUGO | S_IWUSR, get_port1_handler, set_port1_handler);
200 
201 
202 static int cypress_probe(struct usb_interface *interface,
203 			 const struct usb_device_id *id)
204 {
205 	struct cypress *dev = NULL;
206 	int retval = -ENOMEM;
207 
208 	/* allocate memory for our device state and initialize it */
209 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
210 	if (!dev)
211 		goto error_mem;
212 
213 	dev->udev = usb_get_dev(interface_to_usbdev(interface));
214 
215 	/* save our data pointer in this interface device */
216 	usb_set_intfdata(interface, dev);
217 
218 	/* create device attribute files */
219 	retval = device_create_file(&interface->dev, &dev_attr_port0);
220 	if (retval)
221 		goto error;
222 	retval = device_create_file(&interface->dev, &dev_attr_port1);
223 	if (retval)
224 		goto error;
225 
226 	/* let the user know that the device is now attached */
227 	dev_info(&interface->dev,
228 		 "Cypress CY7C63xxx device now attached\n");
229 	return 0;
230 
231 error:
232 	device_remove_file(&interface->dev, &dev_attr_port0);
233 	device_remove_file(&interface->dev, &dev_attr_port1);
234 	usb_set_intfdata(interface, NULL);
235 	usb_put_dev(dev->udev);
236 	kfree(dev);
237 
238 error_mem:
239 	return retval;
240 }
241 
242 static void cypress_disconnect(struct usb_interface *interface)
243 {
244 	struct cypress *dev;
245 
246 	dev = usb_get_intfdata(interface);
247 
248 	/* remove device attribute files */
249 	device_remove_file(&interface->dev, &dev_attr_port0);
250 	device_remove_file(&interface->dev, &dev_attr_port1);
251 	/* the intfdata can be set to NULL only after the
252 	 * device files have been removed */
253 	usb_set_intfdata(interface, NULL);
254 
255 	usb_put_dev(dev->udev);
256 
257 	dev_info(&interface->dev,
258 		 "Cypress CY7C63xxx device now disconnected\n");
259 
260 	kfree(dev);
261 }
262 
263 static struct usb_driver cypress_driver = {
264 	.name = "cypress_cy7c63",
265 	.probe = cypress_probe,
266 	.disconnect = cypress_disconnect,
267 	.id_table = cypress_table,
268 };
269 
270 module_usb_driver(cypress_driver);
271 
272 MODULE_AUTHOR(DRIVER_AUTHOR);
273 MODULE_DESCRIPTION(DRIVER_DESC);
274 
275 MODULE_LICENSE("GPL");
276