1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* -*- linux-c -*- |
3 | * Cypress USB Thermometer driver |
4 | * |
5 | * Copyright (c) 2004 Erik Rigtorp <erkki@linux.nu> <erik@rigtorp.com> |
6 | * |
7 | * This driver works with Elektor magazine USB Interface as published in |
8 | * issue #291. It should also work with the original starter kit/demo board |
9 | * from Cypress. |
10 | */ |
11 | |
12 | |
13 | #include <linux/kernel.h> |
14 | #include <linux/errno.h> |
15 | #include <linux/slab.h> |
16 | #include <linux/module.h> |
17 | #include <linux/usb.h> |
18 | |
19 | #define DRIVER_AUTHOR "Erik Rigtorp" |
20 | #define DRIVER_DESC "Cypress USB Thermometer driver" |
21 | |
22 | #define USB_SKEL_VENDOR_ID 0x04b4 |
23 | #define USB_SKEL_PRODUCT_ID 0x0002 |
24 | |
25 | static const struct usb_device_id id_table[] = { |
26 | { USB_DEVICE(USB_SKEL_VENDOR_ID, USB_SKEL_PRODUCT_ID) }, |
27 | { } |
28 | }; |
29 | MODULE_DEVICE_TABLE (usb, id_table); |
30 | |
31 | /* Structure to hold all of our device specific stuff */ |
32 | struct usb_cytherm { |
33 | struct usb_device *udev; /* save off the usb device pointer */ |
34 | struct usb_interface *interface; /* the interface for this device */ |
35 | int brightness; |
36 | }; |
37 | |
38 | |
39 | /* Vendor requests */ |
40 | /* They all operate on one byte at a time */ |
41 | #define PING 0x00 |
42 | #define READ_ROM 0x01 /* Reads form ROM, value = address */ |
43 | #define READ_RAM 0x02 /* Reads form RAM, value = address */ |
44 | #define WRITE_RAM 0x03 /* Write to RAM, value = address, index = data */ |
45 | #define READ_PORT 0x04 /* Reads from port, value = address */ |
46 | #define WRITE_PORT 0x05 /* Write to port, value = address, index = data */ |
47 | |
48 | |
49 | /* Send a vendor command to device */ |
50 | static int vendor_command(struct usb_device *dev, unsigned char request, |
51 | unsigned char value, unsigned char index, |
52 | void *buf, int size) |
53 | { |
54 | return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), |
55 | request, |
56 | USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_OTHER, |
57 | value, |
58 | index, data: buf, size, |
59 | USB_CTRL_GET_TIMEOUT); |
60 | } |
61 | |
62 | |
63 | |
64 | #define BRIGHTNESS 0x2c /* RAM location for brightness value */ |
65 | #define BRIGHTNESS_SEM 0x2b /* RAM location for brightness semaphore */ |
66 | |
67 | static ssize_t brightness_show(struct device *dev, struct device_attribute *attr, char *buf) |
68 | { |
69 | struct usb_interface *intf = to_usb_interface(dev); |
70 | struct usb_cytherm *cytherm = usb_get_intfdata(intf); |
71 | |
72 | return sprintf(buf, fmt: "%i" , cytherm->brightness); |
73 | } |
74 | |
75 | static ssize_t brightness_store(struct device *dev, struct device_attribute *attr, const char *buf, |
76 | size_t count) |
77 | { |
78 | struct usb_interface *intf = to_usb_interface(dev); |
79 | struct usb_cytherm *cytherm = usb_get_intfdata(intf); |
80 | |
81 | unsigned char *buffer; |
82 | int retval; |
83 | |
84 | buffer = kmalloc(size: 8, GFP_KERNEL); |
85 | if (!buffer) |
86 | return 0; |
87 | |
88 | cytherm->brightness = simple_strtoul(buf, NULL, 10); |
89 | |
90 | if (cytherm->brightness > 0xFF) |
91 | cytherm->brightness = 0xFF; |
92 | else if (cytherm->brightness < 0) |
93 | cytherm->brightness = 0; |
94 | |
95 | /* Set brightness */ |
96 | retval = vendor_command(dev: cytherm->udev, WRITE_RAM, BRIGHTNESS, |
97 | index: cytherm->brightness, buf: buffer, size: 8); |
98 | if (retval) |
99 | dev_dbg(&cytherm->udev->dev, "retval = %d\n" , retval); |
100 | /* Inform µC that we have changed the brightness setting */ |
101 | retval = vendor_command(dev: cytherm->udev, WRITE_RAM, BRIGHTNESS_SEM, |
102 | index: 0x01, buf: buffer, size: 8); |
103 | if (retval) |
104 | dev_dbg(&cytherm->udev->dev, "retval = %d\n" , retval); |
105 | |
106 | kfree(objp: buffer); |
107 | |
108 | return count; |
109 | } |
110 | static DEVICE_ATTR_RW(brightness); |
111 | |
112 | |
113 | #define TEMP 0x33 /* RAM location for temperature */ |
114 | #define SIGN 0x34 /* RAM location for temperature sign */ |
115 | |
116 | static ssize_t temp_show(struct device *dev, struct device_attribute *attr, char *buf) |
117 | { |
118 | |
119 | struct usb_interface *intf = to_usb_interface(dev); |
120 | struct usb_cytherm *cytherm = usb_get_intfdata(intf); |
121 | |
122 | int retval; |
123 | unsigned char *buffer; |
124 | |
125 | int temp, sign; |
126 | |
127 | buffer = kmalloc(size: 8, GFP_KERNEL); |
128 | if (!buffer) |
129 | return 0; |
130 | |
131 | /* read temperature */ |
132 | retval = vendor_command(dev: cytherm->udev, READ_RAM, TEMP, index: 0, buf: buffer, size: 8); |
133 | if (retval) |
134 | dev_dbg(&cytherm->udev->dev, "retval = %d\n" , retval); |
135 | temp = buffer[1]; |
136 | |
137 | /* read sign */ |
138 | retval = vendor_command(dev: cytherm->udev, READ_RAM, SIGN, index: 0, buf: buffer, size: 8); |
139 | if (retval) |
140 | dev_dbg(&cytherm->udev->dev, "retval = %d\n" , retval); |
141 | sign = buffer[1]; |
142 | |
143 | kfree(objp: buffer); |
144 | |
145 | return sprintf(buf, fmt: "%c%i.%i" , sign ? '-' : '+', temp >> 1, |
146 | 5*(temp - ((temp >> 1) << 1))); |
147 | } |
148 | static DEVICE_ATTR_RO(temp); |
149 | |
150 | |
151 | #define BUTTON 0x7a |
152 | |
153 | static ssize_t button_show(struct device *dev, struct device_attribute *attr, char *buf) |
154 | { |
155 | |
156 | struct usb_interface *intf = to_usb_interface(dev); |
157 | struct usb_cytherm *cytherm = usb_get_intfdata(intf); |
158 | |
159 | int retval; |
160 | unsigned char *buffer; |
161 | |
162 | buffer = kmalloc(size: 8, GFP_KERNEL); |
163 | if (!buffer) |
164 | return 0; |
165 | |
166 | /* check button */ |
167 | retval = vendor_command(dev: cytherm->udev, READ_RAM, BUTTON, index: 0, buf: buffer, size: 8); |
168 | if (retval) |
169 | dev_dbg(&cytherm->udev->dev, "retval = %d\n" , retval); |
170 | |
171 | retval = buffer[1]; |
172 | |
173 | kfree(objp: buffer); |
174 | |
175 | if (retval) |
176 | return sprintf(buf, fmt: "1" ); |
177 | else |
178 | return sprintf(buf, fmt: "0" ); |
179 | } |
180 | static DEVICE_ATTR_RO(button); |
181 | |
182 | |
183 | static ssize_t port0_show(struct device *dev, struct device_attribute *attr, char *buf) |
184 | { |
185 | struct usb_interface *intf = to_usb_interface(dev); |
186 | struct usb_cytherm *cytherm = usb_get_intfdata(intf); |
187 | |
188 | int retval; |
189 | unsigned char *buffer; |
190 | |
191 | buffer = kmalloc(size: 8, GFP_KERNEL); |
192 | if (!buffer) |
193 | return 0; |
194 | |
195 | retval = vendor_command(dev: cytherm->udev, READ_PORT, value: 0, index: 0, buf: buffer, size: 8); |
196 | if (retval) |
197 | dev_dbg(&cytherm->udev->dev, "retval = %d\n" , retval); |
198 | |
199 | retval = buffer[1]; |
200 | |
201 | kfree(objp: buffer); |
202 | |
203 | return sprintf(buf, fmt: "%d" , retval); |
204 | } |
205 | |
206 | |
207 | static ssize_t port0_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) |
208 | { |
209 | struct usb_interface *intf = to_usb_interface(dev); |
210 | struct usb_cytherm *cytherm = usb_get_intfdata(intf); |
211 | |
212 | unsigned char *buffer; |
213 | int retval; |
214 | int tmp; |
215 | |
216 | buffer = kmalloc(size: 8, GFP_KERNEL); |
217 | if (!buffer) |
218 | return 0; |
219 | |
220 | tmp = simple_strtoul(buf, NULL, 10); |
221 | |
222 | if (tmp > 0xFF) |
223 | tmp = 0xFF; |
224 | else if (tmp < 0) |
225 | tmp = 0; |
226 | |
227 | retval = vendor_command(dev: cytherm->udev, WRITE_PORT, value: 0, |
228 | index: tmp, buf: buffer, size: 8); |
229 | if (retval) |
230 | dev_dbg(&cytherm->udev->dev, "retval = %d\n" , retval); |
231 | |
232 | kfree(objp: buffer); |
233 | |
234 | return count; |
235 | } |
236 | static DEVICE_ATTR_RW(port0); |
237 | |
238 | static ssize_t port1_show(struct device *dev, struct device_attribute *attr, char *buf) |
239 | { |
240 | struct usb_interface *intf = to_usb_interface(dev); |
241 | struct usb_cytherm *cytherm = usb_get_intfdata(intf); |
242 | |
243 | int retval; |
244 | unsigned char *buffer; |
245 | |
246 | buffer = kmalloc(size: 8, GFP_KERNEL); |
247 | if (!buffer) |
248 | return 0; |
249 | |
250 | retval = vendor_command(dev: cytherm->udev, READ_PORT, value: 1, index: 0, buf: buffer, size: 8); |
251 | if (retval) |
252 | dev_dbg(&cytherm->udev->dev, "retval = %d\n" , retval); |
253 | |
254 | retval = buffer[1]; |
255 | |
256 | kfree(objp: buffer); |
257 | |
258 | return sprintf(buf, fmt: "%d" , retval); |
259 | } |
260 | |
261 | |
262 | static ssize_t port1_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) |
263 | { |
264 | struct usb_interface *intf = to_usb_interface(dev); |
265 | struct usb_cytherm *cytherm = usb_get_intfdata(intf); |
266 | |
267 | unsigned char *buffer; |
268 | int retval; |
269 | int tmp; |
270 | |
271 | buffer = kmalloc(size: 8, GFP_KERNEL); |
272 | if (!buffer) |
273 | return 0; |
274 | |
275 | tmp = simple_strtoul(buf, NULL, 10); |
276 | |
277 | if (tmp > 0xFF) |
278 | tmp = 0xFF; |
279 | else if (tmp < 0) |
280 | tmp = 0; |
281 | |
282 | retval = vendor_command(dev: cytherm->udev, WRITE_PORT, value: 1, |
283 | index: tmp, buf: buffer, size: 8); |
284 | if (retval) |
285 | dev_dbg(&cytherm->udev->dev, "retval = %d\n" , retval); |
286 | |
287 | kfree(objp: buffer); |
288 | |
289 | return count; |
290 | } |
291 | static DEVICE_ATTR_RW(port1); |
292 | |
293 | static struct attribute *cytherm_attrs[] = { |
294 | &dev_attr_brightness.attr, |
295 | &dev_attr_temp.attr, |
296 | &dev_attr_button.attr, |
297 | &dev_attr_port0.attr, |
298 | &dev_attr_port1.attr, |
299 | NULL, |
300 | }; |
301 | ATTRIBUTE_GROUPS(cytherm); |
302 | |
303 | static int cytherm_probe(struct usb_interface *interface, |
304 | const struct usb_device_id *id) |
305 | { |
306 | struct usb_device *udev = interface_to_usbdev(interface); |
307 | struct usb_cytherm *dev; |
308 | int retval = -ENOMEM; |
309 | |
310 | dev = kzalloc(size: sizeof(struct usb_cytherm), GFP_KERNEL); |
311 | if (!dev) |
312 | goto error_mem; |
313 | |
314 | dev->udev = usb_get_dev(dev: udev); |
315 | |
316 | usb_set_intfdata(intf: interface, data: dev); |
317 | |
318 | dev->brightness = 0xFF; |
319 | |
320 | dev_info(&interface->dev, |
321 | "Cypress thermometer device now attached\n" ); |
322 | return 0; |
323 | |
324 | error_mem: |
325 | return retval; |
326 | } |
327 | |
328 | static void cytherm_disconnect(struct usb_interface *interface) |
329 | { |
330 | struct usb_cytherm *dev; |
331 | |
332 | dev = usb_get_intfdata(intf: interface); |
333 | |
334 | /* first remove the files, then NULL the pointer */ |
335 | usb_set_intfdata(intf: interface, NULL); |
336 | |
337 | usb_put_dev(dev: dev->udev); |
338 | |
339 | kfree(objp: dev); |
340 | |
341 | dev_info(&interface->dev, "Cypress thermometer now disconnected\n" ); |
342 | } |
343 | |
344 | /* usb specific object needed to register this driver with the usb subsystem */ |
345 | static struct usb_driver cytherm_driver = { |
346 | .name = "cytherm" , |
347 | .probe = cytherm_probe, |
348 | .disconnect = cytherm_disconnect, |
349 | .id_table = id_table, |
350 | .dev_groups = cytherm_groups, |
351 | }; |
352 | |
353 | module_usb_driver(cytherm_driver); |
354 | |
355 | MODULE_AUTHOR(DRIVER_AUTHOR); |
356 | MODULE_DESCRIPTION(DRIVER_DESC); |
357 | MODULE_LICENSE("GPL" ); |
358 | |