xref: /linux/drivers/usb/misc/usbsevseg.c (revision c0c914eca7f251c70facc37dfebeaf176601918d)
1 /*
2  * USB 7 Segment Driver
3  *
4  * Copyright (C) 2008 Harrison Metzger <harrisonmetz@gmail.com>
5  * Based on usbled.c by Greg Kroah-Hartman (greg@kroah.com)
6  *
7  *	This program is free software; you can redistribute it and/or
8  *	modify it under the terms of the GNU General Public License as
9  *	published by the Free Software Foundation, version 2.
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/string.h>
18 #include <linux/usb.h>
19 
20 
21 #define DRIVER_AUTHOR "Harrison Metzger <harrisonmetz@gmail.com>"
22 #define DRIVER_DESC "USB 7 Segment Driver"
23 
24 #define VENDOR_ID	0x0fc5
25 #define PRODUCT_ID	0x1227
26 #define MAXLEN		8
27 
28 /* table of devices that work with this driver */
29 static const struct usb_device_id id_table[] = {
30 	{ USB_DEVICE(VENDOR_ID, PRODUCT_ID) },
31 	{ },
32 };
33 MODULE_DEVICE_TABLE(usb, id_table);
34 
35 /* the different text display modes the device is capable of */
36 static char *display_textmodes[] = {"raw", "hex", "ascii", NULL};
37 
38 struct usb_sevsegdev {
39 	struct usb_device *udev;
40 	struct usb_interface *intf;
41 
42 	u8 powered;
43 	u8 mode_msb;
44 	u8 mode_lsb;
45 	u8 decimals[MAXLEN];
46 	u8 textmode;
47 	u8 text[MAXLEN];
48 	u16 textlength;
49 
50 	u8 shadow_power; /* for PM */
51 	u8 has_interface_pm;
52 };
53 
54 /* sysfs_streq can't replace this completely
55  * If the device was in hex mode, and the user wanted a 0,
56  * if str commands are used, we would assume the end of string
57  * so mem commands are used.
58  */
59 static inline size_t my_memlen(const char *buf, size_t count)
60 {
61 	if (count > 0 && buf[count-1] == '\n')
62 		return count - 1;
63 	else
64 		return count;
65 }
66 
67 static void update_display_powered(struct usb_sevsegdev *mydev)
68 {
69 	int rc;
70 
71 	if (mydev->powered && !mydev->has_interface_pm) {
72 		rc = usb_autopm_get_interface(mydev->intf);
73 		if (rc < 0)
74 			return;
75 		mydev->has_interface_pm = 1;
76 	}
77 
78 	if (mydev->shadow_power != 1)
79 		return;
80 
81 	rc = usb_control_msg(mydev->udev,
82 			usb_sndctrlpipe(mydev->udev, 0),
83 			0x12,
84 			0x48,
85 			(80 * 0x100) + 10, /*  (power mode) */
86 			(0x00 * 0x100) + (mydev->powered ? 1 : 0),
87 			NULL,
88 			0,
89 			2000);
90 	if (rc < 0)
91 		dev_dbg(&mydev->udev->dev, "power retval = %d\n", rc);
92 
93 	if (!mydev->powered && mydev->has_interface_pm) {
94 		usb_autopm_put_interface(mydev->intf);
95 		mydev->has_interface_pm = 0;
96 	}
97 }
98 
99 static void update_display_mode(struct usb_sevsegdev *mydev)
100 {
101 	int rc;
102 
103 	if(mydev->shadow_power != 1)
104 		return;
105 
106 	rc = usb_control_msg(mydev->udev,
107 			usb_sndctrlpipe(mydev->udev, 0),
108 			0x12,
109 			0x48,
110 			(82 * 0x100) + 10, /* (set mode) */
111 			(mydev->mode_msb * 0x100) + mydev->mode_lsb,
112 			NULL,
113 			0,
114 			2000);
115 
116 	if (rc < 0)
117 		dev_dbg(&mydev->udev->dev, "mode retval = %d\n", rc);
118 }
119 
120 static void update_display_visual(struct usb_sevsegdev *mydev, gfp_t mf)
121 {
122 	int rc;
123 	int i;
124 	unsigned char *buffer;
125 	u8 decimals = 0;
126 
127 	if(mydev->shadow_power != 1)
128 		return;
129 
130 	buffer = kzalloc(MAXLEN, mf);
131 	if (!buffer) {
132 		dev_err(&mydev->udev->dev, "out of memory\n");
133 		return;
134 	}
135 
136 	/* The device is right to left, where as you write left to right */
137 	for (i = 0; i < mydev->textlength; i++)
138 		buffer[i] = mydev->text[mydev->textlength-1-i];
139 
140 	rc = usb_control_msg(mydev->udev,
141 			usb_sndctrlpipe(mydev->udev, 0),
142 			0x12,
143 			0x48,
144 			(85 * 0x100) + 10, /* (write text) */
145 			(0 * 0x100) + mydev->textmode, /* mode  */
146 			buffer,
147 			mydev->textlength,
148 			2000);
149 
150 	if (rc < 0)
151 		dev_dbg(&mydev->udev->dev, "write retval = %d\n", rc);
152 
153 	kfree(buffer);
154 
155 	/* The device is right to left, where as you write left to right */
156 	for (i = 0; i < sizeof(mydev->decimals); i++)
157 		decimals |= mydev->decimals[i] << i;
158 
159 	rc = usb_control_msg(mydev->udev,
160 			usb_sndctrlpipe(mydev->udev, 0),
161 			0x12,
162 			0x48,
163 			(86 * 0x100) + 10, /* (set decimal) */
164 			(0 * 0x100) + decimals, /* decimals */
165 			NULL,
166 			0,
167 			2000);
168 
169 	if (rc < 0)
170 		dev_dbg(&mydev->udev->dev, "decimal retval = %d\n", rc);
171 }
172 
173 #define MYDEV_ATTR_SIMPLE_UNSIGNED(name, update_fcn)		\
174 static ssize_t show_attr_##name(struct device *dev, 		\
175 	struct device_attribute *attr, char *buf) 		\
176 {								\
177 	struct usb_interface *intf = to_usb_interface(dev);	\
178 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);	\
179 								\
180 	return sprintf(buf, "%u\n", mydev->name);		\
181 }								\
182 								\
183 static ssize_t set_attr_##name(struct device *dev, 		\
184 	struct device_attribute *attr, const char *buf, size_t count) \
185 {								\
186 	struct usb_interface *intf = to_usb_interface(dev);	\
187 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);	\
188 								\
189 	mydev->name = simple_strtoul(buf, NULL, 10);		\
190 	update_fcn(mydev); 					\
191 								\
192 	return count;						\
193 }								\
194 static DEVICE_ATTR(name, S_IRUGO | S_IWUSR, show_attr_##name, set_attr_##name);
195 
196 static ssize_t show_attr_text(struct device *dev,
197 	struct device_attribute *attr, char *buf)
198 {
199 	struct usb_interface *intf = to_usb_interface(dev);
200 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
201 
202 	return snprintf(buf, mydev->textlength, "%s\n", mydev->text);
203 }
204 
205 static ssize_t set_attr_text(struct device *dev,
206 	struct device_attribute *attr, const char *buf, size_t count)
207 {
208 	struct usb_interface *intf = to_usb_interface(dev);
209 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
210 	size_t end = my_memlen(buf, count);
211 
212 	if (end > sizeof(mydev->text))
213 		return -EINVAL;
214 
215 	memset(mydev->text, 0, sizeof(mydev->text));
216 	mydev->textlength = end;
217 
218 	if (end > 0)
219 		memcpy(mydev->text, buf, end);
220 
221 	update_display_visual(mydev, GFP_KERNEL);
222 	return count;
223 }
224 
225 static DEVICE_ATTR(text, S_IRUGO | S_IWUSR, show_attr_text, set_attr_text);
226 
227 static ssize_t show_attr_decimals(struct device *dev,
228 	struct device_attribute *attr, char *buf)
229 {
230 	struct usb_interface *intf = to_usb_interface(dev);
231 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
232 	int i;
233 	int pos;
234 
235 	for (i = 0; i < sizeof(mydev->decimals); i++) {
236 		pos = sizeof(mydev->decimals) - 1 - i;
237 		if (mydev->decimals[i] == 0)
238 			buf[pos] = '0';
239 		else if (mydev->decimals[i] == 1)
240 			buf[pos] = '1';
241 		else
242 			buf[pos] = 'x';
243 	}
244 
245 	buf[sizeof(mydev->decimals)] = '\n';
246 	return sizeof(mydev->decimals) + 1;
247 }
248 
249 static ssize_t set_attr_decimals(struct device *dev,
250 	struct device_attribute *attr, const char *buf, size_t count)
251 {
252 	struct usb_interface *intf = to_usb_interface(dev);
253 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
254 	size_t end = my_memlen(buf, count);
255 	int i;
256 
257 	if (end > sizeof(mydev->decimals))
258 		return -EINVAL;
259 
260 	for (i = 0; i < end; i++)
261 		if (buf[i] != '0' && buf[i] != '1')
262 			return -EINVAL;
263 
264 	memset(mydev->decimals, 0, sizeof(mydev->decimals));
265 	for (i = 0; i < end; i++)
266 		if (buf[i] == '1')
267 			mydev->decimals[end-1-i] = 1;
268 
269 	update_display_visual(mydev, GFP_KERNEL);
270 
271 	return count;
272 }
273 
274 static DEVICE_ATTR(decimals, S_IRUGO | S_IWUSR, show_attr_decimals, set_attr_decimals);
275 
276 static ssize_t show_attr_textmode(struct device *dev,
277 	struct device_attribute *attr, char *buf)
278 {
279 	struct usb_interface *intf = to_usb_interface(dev);
280 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
281 	int i;
282 
283 	buf[0] = 0;
284 
285 	for (i = 0; display_textmodes[i]; i++) {
286 		if (mydev->textmode == i) {
287 			strcat(buf, " [");
288 			strcat(buf, display_textmodes[i]);
289 			strcat(buf, "] ");
290 		} else {
291 			strcat(buf, " ");
292 			strcat(buf, display_textmodes[i]);
293 			strcat(buf, " ");
294 		}
295 	}
296 	strcat(buf, "\n");
297 
298 
299 	return strlen(buf);
300 }
301 
302 static ssize_t set_attr_textmode(struct device *dev,
303 	struct device_attribute *attr, const char *buf, size_t count)
304 {
305 	struct usb_interface *intf = to_usb_interface(dev);
306 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
307 	int i;
308 
309 	for (i = 0; display_textmodes[i]; i++) {
310 		if (sysfs_streq(display_textmodes[i], buf)) {
311 			mydev->textmode = i;
312 			update_display_visual(mydev, GFP_KERNEL);
313 			return count;
314 		}
315 	}
316 
317 	return -EINVAL;
318 }
319 
320 static DEVICE_ATTR(textmode, S_IRUGO | S_IWUSR, show_attr_textmode, set_attr_textmode);
321 
322 
323 MYDEV_ATTR_SIMPLE_UNSIGNED(powered, update_display_powered);
324 MYDEV_ATTR_SIMPLE_UNSIGNED(mode_msb, update_display_mode);
325 MYDEV_ATTR_SIMPLE_UNSIGNED(mode_lsb, update_display_mode);
326 
327 static struct attribute *dev_attrs[] = {
328 	&dev_attr_powered.attr,
329 	&dev_attr_text.attr,
330 	&dev_attr_textmode.attr,
331 	&dev_attr_decimals.attr,
332 	&dev_attr_mode_msb.attr,
333 	&dev_attr_mode_lsb.attr,
334 	NULL
335 };
336 
337 static struct attribute_group dev_attr_grp = {
338 	.attrs = dev_attrs,
339 };
340 
341 static int sevseg_probe(struct usb_interface *interface,
342 	const struct usb_device_id *id)
343 {
344 	struct usb_device *udev = interface_to_usbdev(interface);
345 	struct usb_sevsegdev *mydev = NULL;
346 	int rc = -ENOMEM;
347 
348 	mydev = kzalloc(sizeof(struct usb_sevsegdev), GFP_KERNEL);
349 	if (mydev == NULL) {
350 		dev_err(&interface->dev, "Out of memory\n");
351 		goto error_mem;
352 	}
353 
354 	mydev->udev = usb_get_dev(udev);
355 	mydev->intf = interface;
356 	usb_set_intfdata(interface, mydev);
357 
358 	/* PM */
359 	mydev->shadow_power = 1; /* currently active */
360 	mydev->has_interface_pm = 0; /* have not issued autopm_get */
361 
362 	/*set defaults */
363 	mydev->textmode = 0x02; /* ascii mode */
364 	mydev->mode_msb = 0x06; /* 6 characters */
365 	mydev->mode_lsb = 0x3f; /* scanmode for 6 chars */
366 
367 	rc = sysfs_create_group(&interface->dev.kobj, &dev_attr_grp);
368 	if (rc)
369 		goto error;
370 
371 	dev_info(&interface->dev, "USB 7 Segment device now attached\n");
372 	return 0;
373 
374 error:
375 	usb_set_intfdata(interface, NULL);
376 	usb_put_dev(mydev->udev);
377 	kfree(mydev);
378 error_mem:
379 	return rc;
380 }
381 
382 static void sevseg_disconnect(struct usb_interface *interface)
383 {
384 	struct usb_sevsegdev *mydev;
385 
386 	mydev = usb_get_intfdata(interface);
387 	sysfs_remove_group(&interface->dev.kobj, &dev_attr_grp);
388 	usb_set_intfdata(interface, NULL);
389 	usb_put_dev(mydev->udev);
390 	kfree(mydev);
391 	dev_info(&interface->dev, "USB 7 Segment now disconnected\n");
392 }
393 
394 static int sevseg_suspend(struct usb_interface *intf, pm_message_t message)
395 {
396 	struct usb_sevsegdev *mydev;
397 
398 	mydev = usb_get_intfdata(intf);
399 	mydev->shadow_power = 0;
400 
401 	return 0;
402 }
403 
404 static int sevseg_resume(struct usb_interface *intf)
405 {
406 	struct usb_sevsegdev *mydev;
407 
408 	mydev = usb_get_intfdata(intf);
409 	mydev->shadow_power = 1;
410 	update_display_mode(mydev);
411 	update_display_visual(mydev, GFP_NOIO);
412 
413 	return 0;
414 }
415 
416 static int sevseg_reset_resume(struct usb_interface *intf)
417 {
418 	struct usb_sevsegdev *mydev;
419 
420 	mydev = usb_get_intfdata(intf);
421 	mydev->shadow_power = 1;
422 	update_display_mode(mydev);
423 	update_display_visual(mydev, GFP_NOIO);
424 
425 	return 0;
426 }
427 
428 static struct usb_driver sevseg_driver = {
429 	.name =		"usbsevseg",
430 	.probe =	sevseg_probe,
431 	.disconnect =	sevseg_disconnect,
432 	.suspend =	sevseg_suspend,
433 	.resume =	sevseg_resume,
434 	.reset_resume =	sevseg_reset_resume,
435 	.id_table =	id_table,
436 	.supports_autosuspend = 1,
437 };
438 
439 module_usb_driver(sevseg_driver);
440 
441 MODULE_AUTHOR(DRIVER_AUTHOR);
442 MODULE_DESCRIPTION(DRIVER_DESC);
443 MODULE_LICENSE("GPL");
444