xref: /openbmc/linux/drivers/usb/misc/usbsevseg.c (revision 7211ec63)
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 const char *display_textmodes[] = {"raw", "hex", "ascii"};
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 		return;
133 
134 	/* The device is right to left, where as you write left to right */
135 	for (i = 0; i < mydev->textlength; i++)
136 		buffer[i] = mydev->text[mydev->textlength-1-i];
137 
138 	rc = usb_control_msg(mydev->udev,
139 			usb_sndctrlpipe(mydev->udev, 0),
140 			0x12,
141 			0x48,
142 			(85 * 0x100) + 10, /* (write text) */
143 			(0 * 0x100) + mydev->textmode, /* mode  */
144 			buffer,
145 			mydev->textlength,
146 			2000);
147 
148 	if (rc < 0)
149 		dev_dbg(&mydev->udev->dev, "write retval = %d\n", rc);
150 
151 	kfree(buffer);
152 
153 	/* The device is right to left, where as you write left to right */
154 	for (i = 0; i < sizeof(mydev->decimals); i++)
155 		decimals |= mydev->decimals[i] << i;
156 
157 	rc = usb_control_msg(mydev->udev,
158 			usb_sndctrlpipe(mydev->udev, 0),
159 			0x12,
160 			0x48,
161 			(86 * 0x100) + 10, /* (set decimal) */
162 			(0 * 0x100) + decimals, /* decimals */
163 			NULL,
164 			0,
165 			2000);
166 
167 	if (rc < 0)
168 		dev_dbg(&mydev->udev->dev, "decimal retval = %d\n", rc);
169 }
170 
171 #define MYDEV_ATTR_SIMPLE_UNSIGNED(name, update_fcn)		\
172 static ssize_t show_attr_##name(struct device *dev, 		\
173 	struct device_attribute *attr, char *buf) 		\
174 {								\
175 	struct usb_interface *intf = to_usb_interface(dev);	\
176 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);	\
177 								\
178 	return sprintf(buf, "%u\n", mydev->name);		\
179 }								\
180 								\
181 static ssize_t set_attr_##name(struct device *dev, 		\
182 	struct device_attribute *attr, const char *buf, size_t count) \
183 {								\
184 	struct usb_interface *intf = to_usb_interface(dev);	\
185 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);	\
186 								\
187 	mydev->name = simple_strtoul(buf, NULL, 10);		\
188 	update_fcn(mydev); 					\
189 								\
190 	return count;						\
191 }								\
192 static DEVICE_ATTR(name, S_IRUGO | S_IWUSR, show_attr_##name, set_attr_##name);
193 
194 static ssize_t show_attr_text(struct device *dev,
195 	struct device_attribute *attr, char *buf)
196 {
197 	struct usb_interface *intf = to_usb_interface(dev);
198 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
199 
200 	return snprintf(buf, mydev->textlength, "%s\n", mydev->text);
201 }
202 
203 static ssize_t set_attr_text(struct device *dev,
204 	struct device_attribute *attr, const char *buf, size_t count)
205 {
206 	struct usb_interface *intf = to_usb_interface(dev);
207 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
208 	size_t end = my_memlen(buf, count);
209 
210 	if (end > sizeof(mydev->text))
211 		return -EINVAL;
212 
213 	memset(mydev->text, 0, sizeof(mydev->text));
214 	mydev->textlength = end;
215 
216 	if (end > 0)
217 		memcpy(mydev->text, buf, end);
218 
219 	update_display_visual(mydev, GFP_KERNEL);
220 	return count;
221 }
222 
223 static DEVICE_ATTR(text, S_IRUGO | S_IWUSR, show_attr_text, set_attr_text);
224 
225 static ssize_t show_attr_decimals(struct device *dev,
226 	struct device_attribute *attr, char *buf)
227 {
228 	struct usb_interface *intf = to_usb_interface(dev);
229 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
230 	int i;
231 	int pos;
232 
233 	for (i = 0; i < sizeof(mydev->decimals); i++) {
234 		pos = sizeof(mydev->decimals) - 1 - i;
235 		if (mydev->decimals[i] == 0)
236 			buf[pos] = '0';
237 		else if (mydev->decimals[i] == 1)
238 			buf[pos] = '1';
239 		else
240 			buf[pos] = 'x';
241 	}
242 
243 	buf[sizeof(mydev->decimals)] = '\n';
244 	return sizeof(mydev->decimals) + 1;
245 }
246 
247 static ssize_t set_attr_decimals(struct device *dev,
248 	struct device_attribute *attr, const char *buf, size_t count)
249 {
250 	struct usb_interface *intf = to_usb_interface(dev);
251 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
252 	size_t end = my_memlen(buf, count);
253 	int i;
254 
255 	if (end > sizeof(mydev->decimals))
256 		return -EINVAL;
257 
258 	for (i = 0; i < end; i++)
259 		if (buf[i] != '0' && buf[i] != '1')
260 			return -EINVAL;
261 
262 	memset(mydev->decimals, 0, sizeof(mydev->decimals));
263 	for (i = 0; i < end; i++)
264 		if (buf[i] == '1')
265 			mydev->decimals[end-1-i] = 1;
266 
267 	update_display_visual(mydev, GFP_KERNEL);
268 
269 	return count;
270 }
271 
272 static DEVICE_ATTR(decimals, S_IRUGO | S_IWUSR, show_attr_decimals, set_attr_decimals);
273 
274 static ssize_t show_attr_textmode(struct device *dev,
275 	struct device_attribute *attr, char *buf)
276 {
277 	struct usb_interface *intf = to_usb_interface(dev);
278 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
279 	int i;
280 
281 	buf[0] = 0;
282 
283 	for (i = 0; i < ARRAY_SIZE(display_textmodes); i++) {
284 		if (mydev->textmode == i) {
285 			strcat(buf, " [");
286 			strcat(buf, display_textmodes[i]);
287 			strcat(buf, "] ");
288 		} else {
289 			strcat(buf, " ");
290 			strcat(buf, display_textmodes[i]);
291 			strcat(buf, " ");
292 		}
293 	}
294 	strcat(buf, "\n");
295 
296 
297 	return strlen(buf);
298 }
299 
300 static ssize_t set_attr_textmode(struct device *dev,
301 	struct device_attribute *attr, const char *buf, size_t count)
302 {
303 	struct usb_interface *intf = to_usb_interface(dev);
304 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
305 	int i;
306 
307 	i = sysfs_match_string(display_textmodes, buf);
308 	if (i < 0)
309 		return i;
310 
311 	mydev->textmode = i;
312 	update_display_visual(mydev, GFP_KERNEL);
313 	return count;
314 }
315 
316 static DEVICE_ATTR(textmode, S_IRUGO | S_IWUSR, show_attr_textmode, set_attr_textmode);
317 
318 
319 MYDEV_ATTR_SIMPLE_UNSIGNED(powered, update_display_powered);
320 MYDEV_ATTR_SIMPLE_UNSIGNED(mode_msb, update_display_mode);
321 MYDEV_ATTR_SIMPLE_UNSIGNED(mode_lsb, update_display_mode);
322 
323 static struct attribute *dev_attrs[] = {
324 	&dev_attr_powered.attr,
325 	&dev_attr_text.attr,
326 	&dev_attr_textmode.attr,
327 	&dev_attr_decimals.attr,
328 	&dev_attr_mode_msb.attr,
329 	&dev_attr_mode_lsb.attr,
330 	NULL
331 };
332 
333 static const struct attribute_group dev_attr_grp = {
334 	.attrs = dev_attrs,
335 };
336 
337 static int sevseg_probe(struct usb_interface *interface,
338 	const struct usb_device_id *id)
339 {
340 	struct usb_device *udev = interface_to_usbdev(interface);
341 	struct usb_sevsegdev *mydev = NULL;
342 	int rc = -ENOMEM;
343 
344 	mydev = kzalloc(sizeof(struct usb_sevsegdev), GFP_KERNEL);
345 	if (!mydev)
346 		goto error_mem;
347 
348 	mydev->udev = usb_get_dev(udev);
349 	mydev->intf = interface;
350 	usb_set_intfdata(interface, mydev);
351 
352 	/* PM */
353 	mydev->shadow_power = 1; /* currently active */
354 	mydev->has_interface_pm = 0; /* have not issued autopm_get */
355 
356 	/*set defaults */
357 	mydev->textmode = 0x02; /* ascii mode */
358 	mydev->mode_msb = 0x06; /* 6 characters */
359 	mydev->mode_lsb = 0x3f; /* scanmode for 6 chars */
360 
361 	rc = sysfs_create_group(&interface->dev.kobj, &dev_attr_grp);
362 	if (rc)
363 		goto error;
364 
365 	dev_info(&interface->dev, "USB 7 Segment device now attached\n");
366 	return 0;
367 
368 error:
369 	usb_set_intfdata(interface, NULL);
370 	usb_put_dev(mydev->udev);
371 	kfree(mydev);
372 error_mem:
373 	return rc;
374 }
375 
376 static void sevseg_disconnect(struct usb_interface *interface)
377 {
378 	struct usb_sevsegdev *mydev;
379 
380 	mydev = usb_get_intfdata(interface);
381 	sysfs_remove_group(&interface->dev.kobj, &dev_attr_grp);
382 	usb_set_intfdata(interface, NULL);
383 	usb_put_dev(mydev->udev);
384 	kfree(mydev);
385 	dev_info(&interface->dev, "USB 7 Segment now disconnected\n");
386 }
387 
388 static int sevseg_suspend(struct usb_interface *intf, pm_message_t message)
389 {
390 	struct usb_sevsegdev *mydev;
391 
392 	mydev = usb_get_intfdata(intf);
393 	mydev->shadow_power = 0;
394 
395 	return 0;
396 }
397 
398 static int sevseg_resume(struct usb_interface *intf)
399 {
400 	struct usb_sevsegdev *mydev;
401 
402 	mydev = usb_get_intfdata(intf);
403 	mydev->shadow_power = 1;
404 	update_display_mode(mydev);
405 	update_display_visual(mydev, GFP_NOIO);
406 
407 	return 0;
408 }
409 
410 static int sevseg_reset_resume(struct usb_interface *intf)
411 {
412 	struct usb_sevsegdev *mydev;
413 
414 	mydev = usb_get_intfdata(intf);
415 	mydev->shadow_power = 1;
416 	update_display_mode(mydev);
417 	update_display_visual(mydev, GFP_NOIO);
418 
419 	return 0;
420 }
421 
422 static struct usb_driver sevseg_driver = {
423 	.name =		"usbsevseg",
424 	.probe =	sevseg_probe,
425 	.disconnect =	sevseg_disconnect,
426 	.suspend =	sevseg_suspend,
427 	.resume =	sevseg_resume,
428 	.reset_resume =	sevseg_reset_resume,
429 	.id_table =	id_table,
430 	.supports_autosuspend = 1,
431 };
432 
433 module_usb_driver(sevseg_driver);
434 
435 MODULE_AUTHOR(DRIVER_AUTHOR);
436 MODULE_DESCRIPTION(DRIVER_DESC);
437 MODULE_LICENSE("GPL");
438