1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * cypress_cy7c63.c
4 *
5 * Copyright (c) 2006-2007 Oliver Bock (bock@tfh-berlin.de)
6 *
7 * This driver is based on the Cypress USB Driver by Marcus Maul
8 * (cyport) and the 2.0 version of Greg Kroah-Hartman's
9 * USB Skeleton driver.
10 *
11 * This is a generic driver for the Cypress CY7C63xxx family.
12 * For the time being it enables you to read from and write to
13 * the single I/O ports of the device.
14 *
15 * Supported vendors: AK Modul-Bus Computer GmbH
16 * (Firmware "Port-Chip")
17 *
18 * Supported devices: CY7C63001A-PC
19 * CY7C63001C-PXC
20 * CY7C63001C-SXC
21 *
22 * Supported functions: Read/Write Ports
23 *
24 *
25 * For up-to-date information please visit:
26 * http://www.obock.de/kernel/cypress
27 */
28
29 #include <linux/module.h>
30 #include <linux/kernel.h>
31 #include <linux/slab.h>
32 #include <linux/usb.h>
33
34 #define DRIVER_AUTHOR "Oliver Bock (bock@tfh-berlin.de)"
35 #define DRIVER_DESC "Cypress CY7C63xxx USB driver"
36
37 #define CYPRESS_VENDOR_ID 0xa2c
38 #define CYPRESS_PRODUCT_ID 0x8
39
40 #define CYPRESS_READ_PORT 0x4
41 #define CYPRESS_WRITE_PORT 0x5
42
43 #define CYPRESS_READ_RAM 0x2
44 #define CYPRESS_WRITE_RAM 0x3
45 #define CYPRESS_READ_ROM 0x1
46
47 #define CYPRESS_READ_PORT_ID0 0
48 #define CYPRESS_WRITE_PORT_ID0 0
49 #define CYPRESS_READ_PORT_ID1 0x2
50 #define CYPRESS_WRITE_PORT_ID1 1
51
52 #define CYPRESS_MAX_REQSIZE 8
53
54
55 /* table of devices that work with this driver */
56 static const struct usb_device_id cypress_table[] = {
57 { USB_DEVICE(CYPRESS_VENDOR_ID, CYPRESS_PRODUCT_ID) },
58 { }
59 };
60 MODULE_DEVICE_TABLE(usb, cypress_table);
61
62 /* structure to hold all of our device specific stuff */
63 struct cypress {
64 struct usb_device * udev;
65 unsigned char port[2];
66 };
67
68 /* used to send usb control messages to device */
vendor_command(struct cypress * dev,unsigned char request,unsigned char address,unsigned char data)69 static int vendor_command(struct cypress *dev, unsigned char request,
70 unsigned char address, unsigned char data)
71 {
72 int retval = 0;
73 unsigned int pipe;
74 unsigned char *iobuf;
75
76 /* allocate some memory for the i/o buffer*/
77 iobuf = kzalloc(CYPRESS_MAX_REQSIZE, GFP_KERNEL);
78 if (!iobuf) {
79 retval = -ENOMEM;
80 goto error;
81 }
82
83 dev_dbg(&dev->udev->dev, "Sending usb_control_msg (data: %d)\n", data);
84
85 /* prepare usb control message and send it upstream */
86 pipe = usb_rcvctrlpipe(dev->udev, 0);
87 retval = usb_control_msg(dev->udev, pipe, request,
88 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_OTHER,
89 address, data, iobuf, CYPRESS_MAX_REQSIZE,
90 USB_CTRL_GET_TIMEOUT);
91
92 /* store returned data (more READs to be added) */
93 switch (request) {
94 case CYPRESS_READ_PORT:
95 if (address == CYPRESS_READ_PORT_ID0) {
96 dev->port[0] = iobuf[1];
97 dev_dbg(&dev->udev->dev,
98 "READ_PORT0 returned: %d\n",
99 dev->port[0]);
100 }
101 else if (address == CYPRESS_READ_PORT_ID1) {
102 dev->port[1] = iobuf[1];
103 dev_dbg(&dev->udev->dev,
104 "READ_PORT1 returned: %d\n",
105 dev->port[1]);
106 }
107 break;
108 }
109
110 kfree(iobuf);
111 error:
112 return retval;
113 }
114
115 /* write port value */
write_port(struct device * dev,struct device_attribute * attr,const char * buf,size_t count,int port_num,int write_id)116 static ssize_t write_port(struct device *dev, struct device_attribute *attr,
117 const char *buf, size_t count,
118 int port_num, int write_id)
119 {
120 int value = -1;
121 int result = 0;
122
123 struct usb_interface *intf = to_usb_interface(dev);
124 struct cypress *cyp = usb_get_intfdata(intf);
125
126 dev_dbg(&cyp->udev->dev, "WRITE_PORT%d called\n", port_num);
127
128 /* validate input data */
129 if (sscanf(buf, "%d", &value) < 1) {
130 result = -EINVAL;
131 goto error;
132 }
133 if (value < 0 || value > 255) {
134 result = -EINVAL;
135 goto error;
136 }
137
138 result = vendor_command(cyp, CYPRESS_WRITE_PORT, write_id,
139 (unsigned char)value);
140
141 dev_dbg(&cyp->udev->dev, "Result of vendor_command: %d\n\n", result);
142 error:
143 return result < 0 ? result : count;
144 }
145
146 /* attribute callback handler (write) */
port0_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)147 static ssize_t port0_store(struct device *dev,
148 struct device_attribute *attr,
149 const char *buf, size_t count)
150 {
151 return write_port(dev, attr, buf, count, 0, CYPRESS_WRITE_PORT_ID0);
152 }
153
154 /* attribute callback handler (write) */
port1_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)155 static ssize_t port1_store(struct device *dev,
156 struct device_attribute *attr,
157 const char *buf, size_t count)
158 {
159 return write_port(dev, attr, buf, count, 1, CYPRESS_WRITE_PORT_ID1);
160 }
161
162 /* read port value */
read_port(struct device * dev,struct device_attribute * attr,char * buf,int port_num,int read_id)163 static ssize_t read_port(struct device *dev, struct device_attribute *attr,
164 char *buf, int port_num, int read_id)
165 {
166 int result = 0;
167
168 struct usb_interface *intf = to_usb_interface(dev);
169 struct cypress *cyp = usb_get_intfdata(intf);
170
171 dev_dbg(&cyp->udev->dev, "READ_PORT%d called\n", port_num);
172
173 result = vendor_command(cyp, CYPRESS_READ_PORT, read_id, 0);
174
175 dev_dbg(&cyp->udev->dev, "Result of vendor_command: %d\n\n", result);
176
177 return sprintf(buf, "%d", cyp->port[port_num]);
178 }
179
180 /* attribute callback handler (read) */
port0_show(struct device * dev,struct device_attribute * attr,char * buf)181 static ssize_t port0_show(struct device *dev,
182 struct device_attribute *attr, char *buf)
183 {
184 return read_port(dev, attr, buf, 0, CYPRESS_READ_PORT_ID0);
185 }
186 static DEVICE_ATTR_RW(port0);
187
188 /* attribute callback handler (read) */
port1_show(struct device * dev,struct device_attribute * attr,char * buf)189 static ssize_t port1_show(struct device *dev,
190 struct device_attribute *attr, char *buf)
191 {
192 return read_port(dev, attr, buf, 1, CYPRESS_READ_PORT_ID1);
193 }
194 static DEVICE_ATTR_RW(port1);
195
196 static struct attribute *cypress_attrs[] = {
197 &dev_attr_port0.attr,
198 &dev_attr_port1.attr,
199 NULL,
200 };
201 ATTRIBUTE_GROUPS(cypress);
202
cypress_probe(struct usb_interface * interface,const struct usb_device_id * id)203 static int cypress_probe(struct usb_interface *interface,
204 const struct usb_device_id *id)
205 {
206 struct cypress *dev;
207 int retval = -ENOMEM;
208
209 /* allocate memory for our device state and initialize it */
210 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
211 if (!dev)
212 goto error_mem;
213
214 dev->udev = usb_get_dev(interface_to_usbdev(interface));
215
216 /* save our data pointer in this interface device */
217 usb_set_intfdata(interface, dev);
218
219 /* let the user know that the device is now attached */
220 dev_info(&interface->dev,
221 "Cypress CY7C63xxx device now attached\n");
222 return 0;
223
224 error_mem:
225 return retval;
226 }
227
cypress_disconnect(struct usb_interface * interface)228 static void cypress_disconnect(struct usb_interface *interface)
229 {
230 struct cypress *dev;
231
232 dev = usb_get_intfdata(interface);
233
234 /* the intfdata can be set to NULL only after the
235 * device files have been removed */
236 usb_set_intfdata(interface, NULL);
237
238 usb_put_dev(dev->udev);
239
240 dev_info(&interface->dev,
241 "Cypress CY7C63xxx device now disconnected\n");
242
243 kfree(dev);
244 }
245
246 static struct usb_driver cypress_driver = {
247 .name = "cypress_cy7c63",
248 .probe = cypress_probe,
249 .disconnect = cypress_disconnect,
250 .id_table = cypress_table,
251 .dev_groups = cypress_groups,
252 };
253
254 module_usb_driver(cypress_driver);
255
256 MODULE_AUTHOR(DRIVER_AUTHOR);
257 MODULE_DESCRIPTION(DRIVER_DESC);
258
259 MODULE_LICENSE("GPL");
260