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 */
29static const struct usb_device_id id_table[] = {
30	{ USB_DEVICE(VENDOR_ID, PRODUCT_ID) },
31	{ },
32};
33MODULE_DEVICE_TABLE(usb, id_table);
34
35/* the different text display modes the device is capable of */
36static char *display_textmodes[] = {"raw", "hex", "ascii", NULL};
37
38struct 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 */
59static 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
67static 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
99static 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
120static 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)		\
174static 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								\
183static 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}								\
194static DEVICE_ATTR(name, S_IRUGO | S_IWUSR, show_attr_##name, set_attr_##name);
195
196static 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
205static 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
225static DEVICE_ATTR(text, S_IRUGO | S_IWUSR, show_attr_text, set_attr_text);
226
227static 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
249static 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
274static DEVICE_ATTR(decimals, S_IRUGO | S_IWUSR, show_attr_decimals, set_attr_decimals);
275
276static 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
302static 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
320static DEVICE_ATTR(textmode, S_IRUGO | S_IWUSR, show_attr_textmode, set_attr_textmode);
321
322
323MYDEV_ATTR_SIMPLE_UNSIGNED(powered, update_display_powered);
324MYDEV_ATTR_SIMPLE_UNSIGNED(mode_msb, update_display_mode);
325MYDEV_ATTR_SIMPLE_UNSIGNED(mode_lsb, update_display_mode);
326
327static 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
337static struct attribute_group dev_attr_grp = {
338	.attrs = dev_attrs,
339};
340
341static 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
374error:
375	usb_set_intfdata(interface, NULL);
376	usb_put_dev(mydev->udev);
377	kfree(mydev);
378error_mem:
379	return rc;
380}
381
382static 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
394static 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
404static 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
416static 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
428static 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
439module_usb_driver(sevseg_driver);
440
441MODULE_AUTHOR(DRIVER_AUTHOR);
442MODULE_DESCRIPTION(DRIVER_DESC);
443MODULE_LICENSE("GPL");
444