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 */ |
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: dev->udev, pipe, request, |
88 | USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_OTHER, |
89 | value: address, index: data, 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(objp: iobuf); |
111 | error: |
112 | return retval; |
113 | } |
114 | |
115 | /* write port value */ |
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(dev: cyp, CYPRESS_WRITE_PORT, address: write_id, |
139 | data: (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) */ |
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, port_num: 0, CYPRESS_WRITE_PORT_ID0); |
152 | } |
153 | |
154 | /* attribute callback handler (write) */ |
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, port_num: 1, CYPRESS_WRITE_PORT_ID1); |
160 | } |
161 | |
162 | /* read port value */ |
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(dev: cyp, CYPRESS_READ_PORT, address: read_id, data: 0); |
174 | |
175 | dev_dbg(&cyp->udev->dev, "Result of vendor_command: %d\n\n" , result); |
176 | |
177 | return sprintf(buf, fmt: "%d" , cyp->port[port_num]); |
178 | } |
179 | |
180 | /* attribute callback handler (read) */ |
181 | static ssize_t port0_show(struct device *dev, |
182 | struct device_attribute *attr, char *buf) |
183 | { |
184 | return read_port(dev, attr, buf, port_num: 0, CYPRESS_READ_PORT_ID0); |
185 | } |
186 | static DEVICE_ATTR_RW(port0); |
187 | |
188 | /* attribute callback handler (read) */ |
189 | static ssize_t port1_show(struct device *dev, |
190 | struct device_attribute *attr, char *buf) |
191 | { |
192 | return read_port(dev, attr, buf, port_num: 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 | |
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(size: 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(intf: interface, data: 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 | |
228 | static void cypress_disconnect(struct usb_interface *interface) |
229 | { |
230 | struct cypress *dev; |
231 | |
232 | dev = usb_get_intfdata(intf: interface); |
233 | |
234 | /* the intfdata can be set to NULL only after the |
235 | * device files have been removed */ |
236 | usb_set_intfdata(intf: interface, NULL); |
237 | |
238 | usb_put_dev(dev: dev->udev); |
239 | |
240 | dev_info(&interface->dev, |
241 | "Cypress CY7C63xxx device now disconnected\n" ); |
242 | |
243 | kfree(objp: 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 | |