1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * USB 7 Segment Driver
4 *
5 * Copyright (C) 2008 Harrison Metzger <harrisonmetz@gmail.com>
6 * Based on usbled.c by Greg Kroah-Hartman (greg@kroah.com)
7 */
8
9 #include <linux/kernel.h>
10 #include <linux/errno.h>
11 #include <linux/slab.h>
12 #include <linux/module.h>
13 #include <linux/string.h>
14 #include <linux/usb.h>
15
16
17 #define DRIVER_AUTHOR "Harrison Metzger <harrisonmetz@gmail.com>"
18 #define DRIVER_DESC "USB 7 Segment Driver"
19
20 #define VENDOR_ID 0x0fc5
21 #define PRODUCT_ID 0x1227
22 #define MAXLEN 8
23
24 /* table of devices that work with this driver */
25 static const struct usb_device_id id_table[] = {
26 { USB_DEVICE(VENDOR_ID, PRODUCT_ID) },
27 { },
28 };
29 MODULE_DEVICE_TABLE(usb, id_table);
30
31 /* the different text display modes the device is capable of */
32 static const char *display_textmodes[] = {"raw", "hex", "ascii"};
33
34 struct usb_sevsegdev {
35 struct usb_device *udev;
36 struct usb_interface *intf;
37
38 u8 powered;
39 u8 mode_msb;
40 u8 mode_lsb;
41 u8 decimals[MAXLEN];
42 u8 textmode;
43 u8 text[MAXLEN];
44 u16 textlength;
45
46 u8 shadow_power; /* for PM */
47 u8 has_interface_pm;
48 };
49
50 /* sysfs_streq can't replace this completely
51 * If the device was in hex mode, and the user wanted a 0,
52 * if str commands are used, we would assume the end of string
53 * so mem commands are used.
54 */
my_memlen(const char * buf,size_t count)55 static inline size_t my_memlen(const char *buf, size_t count)
56 {
57 if (count > 0 && buf[count-1] == '\n')
58 return count - 1;
59 else
60 return count;
61 }
62
update_display_powered(struct usb_sevsegdev * mydev)63 static void update_display_powered(struct usb_sevsegdev *mydev)
64 {
65 int rc;
66
67 if (mydev->powered && !mydev->has_interface_pm) {
68 rc = usb_autopm_get_interface(mydev->intf);
69 if (rc < 0)
70 return;
71 mydev->has_interface_pm = 1;
72 }
73
74 if (mydev->shadow_power != 1)
75 return;
76
77 rc = usb_control_msg_send(mydev->udev, 0, 0x12, 0x48,
78 (80 * 0x100) + 10, /* (power mode) */
79 (0x00 * 0x100) + (mydev->powered ? 1 : 0),
80 NULL, 0, 2000, GFP_KERNEL);
81 if (rc < 0)
82 dev_dbg(&mydev->udev->dev, "power retval = %d\n", rc);
83
84 if (!mydev->powered && mydev->has_interface_pm) {
85 usb_autopm_put_interface(mydev->intf);
86 mydev->has_interface_pm = 0;
87 }
88 }
89
update_display_mode(struct usb_sevsegdev * mydev)90 static void update_display_mode(struct usb_sevsegdev *mydev)
91 {
92 int rc;
93
94 if(mydev->shadow_power != 1)
95 return;
96
97 rc = usb_control_msg_send(mydev->udev, 0, 0x12, 0x48,
98 (82 * 0x100) + 10, /* (set mode) */
99 (mydev->mode_msb * 0x100) + mydev->mode_lsb,
100 NULL, 0, 2000, GFP_NOIO);
101
102 if (rc < 0)
103 dev_dbg(&mydev->udev->dev, "mode retval = %d\n", rc);
104 }
105
update_display_visual(struct usb_sevsegdev * mydev,gfp_t mf)106 static void update_display_visual(struct usb_sevsegdev *mydev, gfp_t mf)
107 {
108 int rc;
109 int i;
110 unsigned char buffer[MAXLEN] = {0};
111 u8 decimals = 0;
112
113 if(mydev->shadow_power != 1)
114 return;
115
116 /* The device is right to left, where as you write left to right */
117 for (i = 0; i < mydev->textlength; i++)
118 buffer[i] = mydev->text[mydev->textlength-1-i];
119
120 rc = usb_control_msg_send(mydev->udev, 0, 0x12, 0x48,
121 (85 * 0x100) + 10, /* (write text) */
122 (0 * 0x100) + mydev->textmode, /* mode */
123 &buffer, mydev->textlength, 2000, mf);
124
125 if (rc < 0)
126 dev_dbg(&mydev->udev->dev, "write retval = %d\n", rc);
127
128 /* The device is right to left, where as you write left to right */
129 for (i = 0; i < sizeof(mydev->decimals); i++)
130 decimals |= mydev->decimals[i] << i;
131
132 rc = usb_control_msg_send(mydev->udev, 0, 0x12, 0x48,
133 (86 * 0x100) + 10, /* (set decimal) */
134 (0 * 0x100) + decimals, /* decimals */
135 NULL, 0, 2000, mf);
136
137 if (rc < 0)
138 dev_dbg(&mydev->udev->dev, "decimal retval = %d\n", rc);
139 }
140
141 #define MYDEV_ATTR_SIMPLE_UNSIGNED(name, update_fcn) \
142 static ssize_t name##_show(struct device *dev, \
143 struct device_attribute *attr, char *buf) \
144 { \
145 struct usb_interface *intf = to_usb_interface(dev); \
146 struct usb_sevsegdev *mydev = usb_get_intfdata(intf); \
147 \
148 return sprintf(buf, "%u\n", mydev->name); \
149 } \
150 \
151 static ssize_t name##_store(struct device *dev, \
152 struct device_attribute *attr, const char *buf, size_t count) \
153 { \
154 struct usb_interface *intf = to_usb_interface(dev); \
155 struct usb_sevsegdev *mydev = usb_get_intfdata(intf); \
156 \
157 mydev->name = simple_strtoul(buf, NULL, 10); \
158 update_fcn(mydev); \
159 \
160 return count; \
161 } \
162 static DEVICE_ATTR_RW(name);
163
text_show(struct device * dev,struct device_attribute * attr,char * buf)164 static ssize_t text_show(struct device *dev,
165 struct device_attribute *attr, char *buf)
166 {
167 struct usb_interface *intf = to_usb_interface(dev);
168 struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
169
170 return sysfs_emit(buf, "%s\n", mydev->text);
171 }
172
text_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)173 static ssize_t text_store(struct device *dev,
174 struct device_attribute *attr, const char *buf, size_t count)
175 {
176 struct usb_interface *intf = to_usb_interface(dev);
177 struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
178 size_t end = my_memlen(buf, count);
179
180 if (end > sizeof(mydev->text))
181 return -EINVAL;
182
183 memset(mydev->text, 0, sizeof(mydev->text));
184 mydev->textlength = end;
185
186 if (end > 0)
187 memcpy(mydev->text, buf, end);
188
189 update_display_visual(mydev, GFP_KERNEL);
190 return count;
191 }
192
193 static DEVICE_ATTR_RW(text);
194
decimals_show(struct device * dev,struct device_attribute * attr,char * buf)195 static ssize_t decimals_show(struct device *dev,
196 struct device_attribute *attr, char *buf)
197 {
198 struct usb_interface *intf = to_usb_interface(dev);
199 struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
200 int i;
201 int pos;
202
203 for (i = 0; i < sizeof(mydev->decimals); i++) {
204 pos = sizeof(mydev->decimals) - 1 - i;
205 if (mydev->decimals[i] == 0)
206 buf[pos] = '0';
207 else if (mydev->decimals[i] == 1)
208 buf[pos] = '1';
209 else
210 buf[pos] = 'x';
211 }
212
213 buf[sizeof(mydev->decimals)] = '\n';
214 return sizeof(mydev->decimals) + 1;
215 }
216
decimals_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)217 static ssize_t decimals_store(struct device *dev,
218 struct device_attribute *attr, const char *buf, size_t count)
219 {
220 struct usb_interface *intf = to_usb_interface(dev);
221 struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
222 size_t end = my_memlen(buf, count);
223 int i;
224
225 if (end > sizeof(mydev->decimals))
226 return -EINVAL;
227
228 for (i = 0; i < end; i++)
229 if (buf[i] != '0' && buf[i] != '1')
230 return -EINVAL;
231
232 memset(mydev->decimals, 0, sizeof(mydev->decimals));
233 for (i = 0; i < end; i++)
234 if (buf[i] == '1')
235 mydev->decimals[end-1-i] = 1;
236
237 update_display_visual(mydev, GFP_KERNEL);
238
239 return count;
240 }
241
242 static DEVICE_ATTR_RW(decimals);
243
textmode_show(struct device * dev,struct device_attribute * attr,char * buf)244 static ssize_t textmode_show(struct device *dev,
245 struct device_attribute *attr, char *buf)
246 {
247 struct usb_interface *intf = to_usb_interface(dev);
248 struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
249 int i;
250
251 buf[0] = 0;
252
253 for (i = 0; i < ARRAY_SIZE(display_textmodes); i++) {
254 if (mydev->textmode == i) {
255 strcat(buf, " [");
256 strcat(buf, display_textmodes[i]);
257 strcat(buf, "] ");
258 } else {
259 strcat(buf, " ");
260 strcat(buf, display_textmodes[i]);
261 strcat(buf, " ");
262 }
263 }
264 strcat(buf, "\n");
265
266
267 return strlen(buf);
268 }
269
textmode_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)270 static ssize_t textmode_store(struct device *dev,
271 struct device_attribute *attr, const char *buf, size_t count)
272 {
273 struct usb_interface *intf = to_usb_interface(dev);
274 struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
275 int i;
276
277 i = sysfs_match_string(display_textmodes, buf);
278 if (i < 0)
279 return i;
280
281 mydev->textmode = i;
282 update_display_visual(mydev, GFP_KERNEL);
283 return count;
284 }
285
286 static DEVICE_ATTR_RW(textmode);
287
288
289 MYDEV_ATTR_SIMPLE_UNSIGNED(powered, update_display_powered);
290 MYDEV_ATTR_SIMPLE_UNSIGNED(mode_msb, update_display_mode);
291 MYDEV_ATTR_SIMPLE_UNSIGNED(mode_lsb, update_display_mode);
292
293 static struct attribute *sevseg_attrs[] = {
294 &dev_attr_powered.attr,
295 &dev_attr_text.attr,
296 &dev_attr_textmode.attr,
297 &dev_attr_decimals.attr,
298 &dev_attr_mode_msb.attr,
299 &dev_attr_mode_lsb.attr,
300 NULL
301 };
302 ATTRIBUTE_GROUPS(sevseg);
303
sevseg_probe(struct usb_interface * interface,const struct usb_device_id * id)304 static int sevseg_probe(struct usb_interface *interface,
305 const struct usb_device_id *id)
306 {
307 struct usb_device *udev = interface_to_usbdev(interface);
308 struct usb_sevsegdev *mydev;
309 int rc = -ENOMEM;
310
311 mydev = kzalloc(sizeof(struct usb_sevsegdev), GFP_KERNEL);
312 if (!mydev)
313 goto error_mem;
314
315 mydev->udev = usb_get_dev(udev);
316 mydev->intf = interface;
317 usb_set_intfdata(interface, mydev);
318
319 /* PM */
320 mydev->shadow_power = 1; /* currently active */
321 mydev->has_interface_pm = 0; /* have not issued autopm_get */
322
323 /*set defaults */
324 mydev->textmode = 0x02; /* ascii mode */
325 mydev->mode_msb = 0x06; /* 6 characters */
326 mydev->mode_lsb = 0x3f; /* scanmode for 6 chars */
327
328 dev_info(&interface->dev, "USB 7 Segment device now attached\n");
329 return 0;
330
331 error_mem:
332 return rc;
333 }
334
sevseg_disconnect(struct usb_interface * interface)335 static void sevseg_disconnect(struct usb_interface *interface)
336 {
337 struct usb_sevsegdev *mydev;
338
339 mydev = usb_get_intfdata(interface);
340 usb_set_intfdata(interface, NULL);
341 usb_put_dev(mydev->udev);
342 kfree(mydev);
343 dev_info(&interface->dev, "USB 7 Segment now disconnected\n");
344 }
345
sevseg_suspend(struct usb_interface * intf,pm_message_t message)346 static int sevseg_suspend(struct usb_interface *intf, pm_message_t message)
347 {
348 struct usb_sevsegdev *mydev;
349
350 mydev = usb_get_intfdata(intf);
351 mydev->shadow_power = 0;
352
353 return 0;
354 }
355
sevseg_resume(struct usb_interface * intf)356 static int sevseg_resume(struct usb_interface *intf)
357 {
358 struct usb_sevsegdev *mydev;
359
360 mydev = usb_get_intfdata(intf);
361 mydev->shadow_power = 1;
362 update_display_mode(mydev);
363 update_display_visual(mydev, GFP_NOIO);
364
365 return 0;
366 }
367
sevseg_reset_resume(struct usb_interface * intf)368 static int sevseg_reset_resume(struct usb_interface *intf)
369 {
370 struct usb_sevsegdev *mydev;
371
372 mydev = usb_get_intfdata(intf);
373 mydev->shadow_power = 1;
374 update_display_mode(mydev);
375 update_display_visual(mydev, GFP_NOIO);
376
377 return 0;
378 }
379
380 static struct usb_driver sevseg_driver = {
381 .name = "usbsevseg",
382 .probe = sevseg_probe,
383 .disconnect = sevseg_disconnect,
384 .suspend = sevseg_suspend,
385 .resume = sevseg_resume,
386 .reset_resume = sevseg_reset_resume,
387 .id_table = id_table,
388 .dev_groups = sevseg_groups,
389 .supports_autosuspend = 1,
390 };
391
392 module_usb_driver(sevseg_driver);
393
394 MODULE_AUTHOR(DRIVER_AUTHOR);
395 MODULE_DESCRIPTION(DRIVER_DESC);
396 MODULE_LICENSE("GPL");
397