1 /* -*- linux-c -*-
2 * Cypress USB Thermometer driver
3 *
4 * Copyright (c) 2004 Erik Rigtorp <erkki@linux.nu> <erik@rigtorp.com>
5 *
6 * This driver works with Elektor magazine USB Interface as published in
7 * issue #291. It should also work with the original starter kit/demo board
8 * from Cypress.
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License as
12 * published by the Free Software Foundation, version 2.
13 *
14 */
15
16
17 #include <linux/kernel.h>
18 #include <linux/errno.h>
19 #include <linux/init.h>
20 #include <linux/module.h>
21 #include <linux/usb.h>
22
23 #define DRIVER_VERSION "v1.0"
24 #define DRIVER_AUTHOR "Erik Rigtorp"
25 #define DRIVER_DESC "Cypress USB Thermometer driver"
26
27 #define USB_SKEL_VENDOR_ID 0x04b4
28 #define USB_SKEL_PRODUCT_ID 0x0002
29
30 static struct usb_device_id id_table [] = {
31 { USB_DEVICE(USB_SKEL_VENDOR_ID, USB_SKEL_PRODUCT_ID) },
32 { }
33 };
34 MODULE_DEVICE_TABLE (usb, id_table);
35
36 /* Structure to hold all of our device specific stuff */
37 struct usb_cytherm {
38 struct usb_device *udev; /* save off the usb device pointer */
39 struct usb_interface *interface; /* the interface for this device */
40 int brightness;
41 };
42
43
44 /* local function prototypes */
45 static int cytherm_probe(struct usb_interface *interface,
46 const struct usb_device_id *id);
47 static void cytherm_disconnect(struct usb_interface *interface);
48
49
50 /* usb specific object needed to register this driver with the usb subsystem */
51 static struct usb_driver cytherm_driver = {
52 .name = "cytherm",
53 .probe = cytherm_probe,
54 .disconnect = cytherm_disconnect,
55 .id_table = id_table,
56 };
57
58 /* Vendor requests */
59 /* They all operate on one byte at a time */
60 #define PING 0x00
61 #define READ_ROM 0x01 /* Reads form ROM, value = address */
62 #define READ_RAM 0x02 /* Reads form RAM, value = address */
63 #define WRITE_RAM 0x03 /* Write to RAM, value = address, index = data */
64 #define READ_PORT 0x04 /* Reads from port, value = address */
65 #define WRITE_PORT 0x05 /* Write to port, value = address, index = data */
66
67
68 /* Send a vendor command to device */
vendor_command(struct usb_device * dev,unsigned char request,unsigned char value,unsigned char index,void * buf,int size)69 static int vendor_command(struct usb_device *dev, unsigned char request,
70 unsigned char value, unsigned char index,
71 void *buf, int size)
72 {
73 return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
74 request,
75 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_OTHER,
76 value,
77 index, buf, size,
78 USB_CTRL_GET_TIMEOUT);
79 }
80
81
82
83 #define BRIGHTNESS 0x2c /* RAM location for brightness value */
84 #define BRIGHTNESS_SEM 0x2b /* RAM location for brightness semaphore */
85
show_brightness(struct device * dev,struct device_attribute * attr,char * buf)86 static ssize_t show_brightness(struct device *dev, struct device_attribute *attr, char *buf)
87 {
88 struct usb_interface *intf = to_usb_interface(dev);
89 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
90
91 return sprintf(buf, "%i", cytherm->brightness);
92 }
93
set_brightness(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)94 static ssize_t set_brightness(struct device *dev, struct device_attribute *attr, const char *buf,
95 size_t count)
96 {
97 struct usb_interface *intf = to_usb_interface(dev);
98 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
99
100 unsigned char *buffer;
101 int retval;
102
103 buffer = kmalloc(8, GFP_KERNEL);
104 if (!buffer) {
105 dev_err(&cytherm->udev->dev, "out of memory\n");
106 return 0;
107 }
108
109 cytherm->brightness = simple_strtoul(buf, NULL, 10);
110
111 if (cytherm->brightness > 0xFF)
112 cytherm->brightness = 0xFF;
113 else if (cytherm->brightness < 0)
114 cytherm->brightness = 0;
115
116 /* Set brightness */
117 retval = vendor_command(cytherm->udev, WRITE_RAM, BRIGHTNESS,
118 cytherm->brightness, buffer, 8);
119 if (retval)
120 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
121 /* Inform µC that we have changed the brightness setting */
122 retval = vendor_command(cytherm->udev, WRITE_RAM, BRIGHTNESS_SEM,
123 0x01, buffer, 8);
124 if (retval)
125 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
126
127 kfree(buffer);
128
129 return count;
130 }
131
132 static DEVICE_ATTR(brightness, S_IRUGO | S_IWUSR | S_IWGRP,
133 show_brightness, set_brightness);
134
135
136 #define TEMP 0x33 /* RAM location for temperature */
137 #define SIGN 0x34 /* RAM location for temperature sign */
138
show_temp(struct device * dev,struct device_attribute * attr,char * buf)139 static ssize_t show_temp(struct device *dev, struct device_attribute *attr, char *buf)
140 {
141
142 struct usb_interface *intf = to_usb_interface(dev);
143 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
144
145 int retval;
146 unsigned char *buffer;
147
148 int temp, sign;
149
150 buffer = kmalloc(8, GFP_KERNEL);
151 if (!buffer) {
152 dev_err(&cytherm->udev->dev, "out of memory\n");
153 return 0;
154 }
155
156 /* read temperature */
157 retval = vendor_command(cytherm->udev, READ_RAM, TEMP, 0, buffer, 8);
158 if (retval)
159 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
160 temp = buffer[1];
161
162 /* read sign */
163 retval = vendor_command(cytherm->udev, READ_RAM, SIGN, 0, buffer, 8);
164 if (retval)
165 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
166 sign = buffer[1];
167
168 kfree(buffer);
169
170 return sprintf(buf, "%c%i.%i", sign ? '-' : '+', temp >> 1,
171 5*(temp - ((temp >> 1) << 1)));
172 }
173
174
set_temp(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)175 static ssize_t set_temp(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
176 {
177 return count;
178 }
179
180 static DEVICE_ATTR(temp, S_IRUGO, show_temp, set_temp);
181
182
183 #define BUTTON 0x7a
184
show_button(struct device * dev,struct device_attribute * attr,char * buf)185 static ssize_t show_button(struct device *dev, struct device_attribute *attr, char *buf)
186 {
187
188 struct usb_interface *intf = to_usb_interface(dev);
189 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
190
191 int retval;
192 unsigned char *buffer;
193
194 buffer = kmalloc(8, GFP_KERNEL);
195 if (!buffer) {
196 dev_err(&cytherm->udev->dev, "out of memory\n");
197 return 0;
198 }
199
200 /* check button */
201 retval = vendor_command(cytherm->udev, READ_RAM, BUTTON, 0, buffer, 8);
202 if (retval)
203 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
204
205 retval = buffer[1];
206
207 kfree(buffer);
208
209 if (retval)
210 return sprintf(buf, "1");
211 else
212 return sprintf(buf, "0");
213 }
214
215
set_button(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)216 static ssize_t set_button(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
217 {
218 return count;
219 }
220
221 static DEVICE_ATTR(button, S_IRUGO, show_button, set_button);
222
223
show_port0(struct device * dev,struct device_attribute * attr,char * buf)224 static ssize_t show_port0(struct device *dev, struct device_attribute *attr, char *buf)
225 {
226 struct usb_interface *intf = to_usb_interface(dev);
227 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
228
229 int retval;
230 unsigned char *buffer;
231
232 buffer = kmalloc(8, GFP_KERNEL);
233 if (!buffer) {
234 dev_err(&cytherm->udev->dev, "out of memory\n");
235 return 0;
236 }
237
238 retval = vendor_command(cytherm->udev, READ_PORT, 0, 0, buffer, 8);
239 if (retval)
240 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
241
242 retval = buffer[1];
243
244 kfree(buffer);
245
246 return sprintf(buf, "%d", retval);
247 }
248
249
set_port0(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)250 static ssize_t set_port0(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
251 {
252 struct usb_interface *intf = to_usb_interface(dev);
253 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
254
255 unsigned char *buffer;
256 int retval;
257 int tmp;
258
259 buffer = kmalloc(8, GFP_KERNEL);
260 if (!buffer) {
261 dev_err(&cytherm->udev->dev, "out of memory\n");
262 return 0;
263 }
264
265 tmp = simple_strtoul(buf, NULL, 10);
266
267 if (tmp > 0xFF)
268 tmp = 0xFF;
269 else if (tmp < 0)
270 tmp = 0;
271
272 retval = vendor_command(cytherm->udev, WRITE_PORT, 0,
273 tmp, buffer, 8);
274 if (retval)
275 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
276
277 kfree(buffer);
278
279 return count;
280 }
281
282 static DEVICE_ATTR(port0, S_IRUGO | S_IWUSR | S_IWGRP, show_port0, set_port0);
283
show_port1(struct device * dev,struct device_attribute * attr,char * buf)284 static ssize_t show_port1(struct device *dev, struct device_attribute *attr, char *buf)
285 {
286 struct usb_interface *intf = to_usb_interface(dev);
287 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
288
289 int retval;
290 unsigned char *buffer;
291
292 buffer = kmalloc(8, GFP_KERNEL);
293 if (!buffer) {
294 dev_err(&cytherm->udev->dev, "out of memory\n");
295 return 0;
296 }
297
298 retval = vendor_command(cytherm->udev, READ_PORT, 1, 0, buffer, 8);
299 if (retval)
300 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
301
302 retval = buffer[1];
303
304 kfree(buffer);
305
306 return sprintf(buf, "%d", retval);
307 }
308
309
set_port1(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)310 static ssize_t set_port1(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
311 {
312 struct usb_interface *intf = to_usb_interface(dev);
313 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
314
315 unsigned char *buffer;
316 int retval;
317 int tmp;
318
319 buffer = kmalloc(8, GFP_KERNEL);
320 if (!buffer) {
321 dev_err(&cytherm->udev->dev, "out of memory\n");
322 return 0;
323 }
324
325 tmp = simple_strtoul(buf, NULL, 10);
326
327 if (tmp > 0xFF)
328 tmp = 0xFF;
329 else if (tmp < 0)
330 tmp = 0;
331
332 retval = vendor_command(cytherm->udev, WRITE_PORT, 1,
333 tmp, buffer, 8);
334 if (retval)
335 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
336
337 kfree(buffer);
338
339 return count;
340 }
341
342 static DEVICE_ATTR(port1, S_IRUGO | S_IWUSR | S_IWGRP, show_port1, set_port1);
343
344
345
cytherm_probe(struct usb_interface * interface,const struct usb_device_id * id)346 static int cytherm_probe(struct usb_interface *interface,
347 const struct usb_device_id *id)
348 {
349 struct usb_device *udev = interface_to_usbdev(interface);
350 struct usb_cytherm *dev = NULL;
351 int retval = -ENOMEM;
352
353 dev = kzalloc (sizeof(struct usb_cytherm), GFP_KERNEL);
354 if (dev == NULL) {
355 dev_err (&interface->dev, "Out of memory\n");
356 goto error_mem;
357 }
358
359 dev->udev = usb_get_dev(udev);
360
361 usb_set_intfdata (interface, dev);
362
363 dev->brightness = 0xFF;
364
365 retval = device_create_file(&interface->dev, &dev_attr_brightness);
366 if (retval)
367 goto error;
368 retval = device_create_file(&interface->dev, &dev_attr_temp);
369 if (retval)
370 goto error;
371 retval = device_create_file(&interface->dev, &dev_attr_button);
372 if (retval)
373 goto error;
374 retval = device_create_file(&interface->dev, &dev_attr_port0);
375 if (retval)
376 goto error;
377 retval = device_create_file(&interface->dev, &dev_attr_port1);
378 if (retval)
379 goto error;
380
381 dev_info (&interface->dev,
382 "Cypress thermometer device now attached\n");
383 return 0;
384 error:
385 device_remove_file(&interface->dev, &dev_attr_brightness);
386 device_remove_file(&interface->dev, &dev_attr_temp);
387 device_remove_file(&interface->dev, &dev_attr_button);
388 device_remove_file(&interface->dev, &dev_attr_port0);
389 device_remove_file(&interface->dev, &dev_attr_port1);
390 usb_set_intfdata (interface, NULL);
391 usb_put_dev(dev->udev);
392 kfree(dev);
393 error_mem:
394 return retval;
395 }
396
cytherm_disconnect(struct usb_interface * interface)397 static void cytherm_disconnect(struct usb_interface *interface)
398 {
399 struct usb_cytherm *dev;
400
401 dev = usb_get_intfdata (interface);
402
403 device_remove_file(&interface->dev, &dev_attr_brightness);
404 device_remove_file(&interface->dev, &dev_attr_temp);
405 device_remove_file(&interface->dev, &dev_attr_button);
406 device_remove_file(&interface->dev, &dev_attr_port0);
407 device_remove_file(&interface->dev, &dev_attr_port1);
408
409 /* first remove the files, then NULL the pointer */
410 usb_set_intfdata (interface, NULL);
411
412 usb_put_dev(dev->udev);
413
414 kfree(dev);
415
416 dev_info(&interface->dev, "Cypress thermometer now disconnected\n");
417 }
418
419
usb_cytherm_init(void)420 static int __init usb_cytherm_init(void)
421 {
422 int result;
423
424 result = usb_register(&cytherm_driver);
425 if (result) {
426 printk(KERN_ERR KBUILD_MODNAME ": usb_register failed! "
427 "Error number: %d\n", result);
428 return result;
429 }
430
431 printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
432 DRIVER_DESC "\n");
433 return 0;
434 }
435
usb_cytherm_exit(void)436 static void __exit usb_cytherm_exit(void)
437 {
438 usb_deregister(&cytherm_driver);
439 }
440
441
442 module_init (usb_cytherm_init);
443 module_exit (usb_cytherm_exit);
444
445 MODULE_AUTHOR(DRIVER_AUTHOR);
446 MODULE_DESCRIPTION(DRIVER_DESC);
447 MODULE_LICENSE("GPL");
448