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15#include <linux/module.h>
16#include <linux/kernel.h>
17#include <linux/init.h>
18#include <linux/slab.h>
19#include <linux/errno.h>
20#include <linux/mutex.h>
21#include <linux/uaccess.h>
22#include <linux/usb.h>
23
24#define DRIVER_VERSION "USBLCD Driver Version 1.05"
25
26#define USBLCD_MINOR 144
27
28#define IOCTL_GET_HARD_VERSION 1
29#define IOCTL_GET_DRV_VERSION 2
30
31
32static DEFINE_MUTEX(lcd_mutex);
33static const struct usb_device_id id_table[] = {
34 { .idVendor = 0x10D2, .match_flags = USB_DEVICE_ID_MATCH_VENDOR, },
35 { },
36};
37MODULE_DEVICE_TABLE(usb, id_table);
38
39static DEFINE_MUTEX(open_disc_mutex);
40
41
42struct usb_lcd {
43 struct usb_device *udev;
44 struct usb_interface *interface;
45
46 unsigned char *bulk_in_buffer;
47
48 size_t bulk_in_size;
49
50 __u8 bulk_in_endpointAddr;
51
52 __u8 bulk_out_endpointAddr;
53
54 struct kref kref;
55 struct semaphore limit_sem;
56
57
58 struct usb_anchor submitted;
59
60};
61#define to_lcd_dev(d) container_of(d, struct usb_lcd, kref)
62
63#define USB_LCD_CONCURRENT_WRITES 5
64
65static struct usb_driver lcd_driver;
66
67
68static void lcd_delete(struct kref *kref)
69{
70 struct usb_lcd *dev = to_lcd_dev(kref);
71
72 usb_put_dev(dev->udev);
73 kfree(dev->bulk_in_buffer);
74 kfree(dev);
75}
76
77
78static int lcd_open(struct inode *inode, struct file *file)
79{
80 struct usb_lcd *dev;
81 struct usb_interface *interface;
82 int subminor, r;
83
84 mutex_lock(&lcd_mutex);
85 subminor = iminor(inode);
86
87 interface = usb_find_interface(&lcd_driver, subminor);
88 if (!interface) {
89 mutex_unlock(&lcd_mutex);
90 printk(KERN_ERR "USBLCD: %s - error, can't find device for minor %d\n",
91 __func__, subminor);
92 return -ENODEV;
93 }
94
95 mutex_lock(&open_disc_mutex);
96 dev = usb_get_intfdata(interface);
97 if (!dev) {
98 mutex_unlock(&open_disc_mutex);
99 mutex_unlock(&lcd_mutex);
100 return -ENODEV;
101 }
102
103
104 kref_get(&dev->kref);
105 mutex_unlock(&open_disc_mutex);
106
107
108 r = usb_autopm_get_interface(interface);
109 if (r < 0) {
110 kref_put(&dev->kref, lcd_delete);
111 mutex_unlock(&lcd_mutex);
112 return r;
113 }
114
115
116 file->private_data = dev;
117 mutex_unlock(&lcd_mutex);
118
119 return 0;
120}
121
122static int lcd_release(struct inode *inode, struct file *file)
123{
124 struct usb_lcd *dev;
125
126 dev = file->private_data;
127 if (dev == NULL)
128 return -ENODEV;
129
130
131 usb_autopm_put_interface(dev->interface);
132 kref_put(&dev->kref, lcd_delete);
133 return 0;
134}
135
136static ssize_t lcd_read(struct file *file, char __user * buffer,
137 size_t count, loff_t *ppos)
138{
139 struct usb_lcd *dev;
140 int retval = 0;
141 int bytes_read;
142
143 dev = file->private_data;
144
145
146 retval = usb_bulk_msg(dev->udev,
147 usb_rcvbulkpipe(dev->udev,
148 dev->bulk_in_endpointAddr),
149 dev->bulk_in_buffer,
150 min(dev->bulk_in_size, count),
151 &bytes_read, 10000);
152
153
154 if (!retval) {
155 if (copy_to_user(buffer, dev->bulk_in_buffer, bytes_read))
156 retval = -EFAULT;
157 else
158 retval = bytes_read;
159 }
160
161 return retval;
162}
163
164static long lcd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
165{
166 struct usb_lcd *dev;
167 u16 bcdDevice;
168 char buf[30];
169
170 dev = file->private_data;
171 if (dev == NULL)
172 return -ENODEV;
173
174 switch (cmd) {
175 case IOCTL_GET_HARD_VERSION:
176 mutex_lock(&lcd_mutex);
177 bcdDevice = le16_to_cpu((dev->udev)->descriptor.bcdDevice);
178 sprintf(buf, "%1d%1d.%1d%1d",
179 (bcdDevice & 0xF000)>>12,
180 (bcdDevice & 0xF00)>>8,
181 (bcdDevice & 0xF0)>>4,
182 (bcdDevice & 0xF));
183 mutex_unlock(&lcd_mutex);
184 if (copy_to_user((void __user *)arg, buf, strlen(buf)) != 0)
185 return -EFAULT;
186 break;
187 case IOCTL_GET_DRV_VERSION:
188 sprintf(buf, DRIVER_VERSION);
189 if (copy_to_user((void __user *)arg, buf, strlen(buf)) != 0)
190 return -EFAULT;
191 break;
192 default:
193 return -ENOTTY;
194 break;
195 }
196
197 return 0;
198}
199
200static void lcd_write_bulk_callback(struct urb *urb)
201{
202 struct usb_lcd *dev;
203 int status = urb->status;
204
205 dev = urb->context;
206
207
208 if (status &&
209 !(status == -ENOENT ||
210 status == -ECONNRESET ||
211 status == -ESHUTDOWN)) {
212 dev_dbg(&dev->interface->dev,
213 "nonzero write bulk status received: %d\n", status);
214 }
215
216
217 usb_free_coherent(urb->dev, urb->transfer_buffer_length,
218 urb->transfer_buffer, urb->transfer_dma);
219 up(&dev->limit_sem);
220}
221
222static ssize_t lcd_write(struct file *file, const char __user * user_buffer,
223 size_t count, loff_t *ppos)
224{
225 struct usb_lcd *dev;
226 int retval = 0, r;
227 struct urb *urb = NULL;
228 char *buf = NULL;
229
230 dev = file->private_data;
231
232
233 if (count == 0)
234 goto exit;
235
236 r = down_interruptible(&dev->limit_sem);
237 if (r < 0)
238 return -EINTR;
239
240
241 urb = usb_alloc_urb(0, GFP_KERNEL);
242 if (!urb) {
243 retval = -ENOMEM;
244 goto err_no_buf;
245 }
246
247 buf = usb_alloc_coherent(dev->udev, count, GFP_KERNEL,
248 &urb->transfer_dma);
249 if (!buf) {
250 retval = -ENOMEM;
251 goto error;
252 }
253
254 if (copy_from_user(buf, user_buffer, count)) {
255 retval = -EFAULT;
256 goto error;
257 }
258
259
260 usb_fill_bulk_urb(urb, dev->udev,
261 usb_sndbulkpipe(dev->udev,
262 dev->bulk_out_endpointAddr),
263 buf, count, lcd_write_bulk_callback, dev);
264 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
265
266 usb_anchor_urb(urb, &dev->submitted);
267
268
269 retval = usb_submit_urb(urb, GFP_KERNEL);
270 if (retval) {
271 dev_err(&dev->udev->dev,
272 "%s - failed submitting write urb, error %d\n",
273 __func__, retval);
274 goto error_unanchor;
275 }
276
277
278
279 usb_free_urb(urb);
280
281exit:
282 return count;
283error_unanchor:
284 usb_unanchor_urb(urb);
285error:
286 usb_free_coherent(dev->udev, count, buf, urb->transfer_dma);
287 usb_free_urb(urb);
288err_no_buf:
289 up(&dev->limit_sem);
290 return retval;
291}
292
293static const struct file_operations lcd_fops = {
294 .owner = THIS_MODULE,
295 .read = lcd_read,
296 .write = lcd_write,
297 .open = lcd_open,
298 .unlocked_ioctl = lcd_ioctl,
299 .release = lcd_release,
300 .llseek = noop_llseek,
301};
302
303
304
305
306
307static struct usb_class_driver lcd_class = {
308 .name = "lcd%d",
309 .fops = &lcd_fops,
310 .minor_base = USBLCD_MINOR,
311};
312
313static int lcd_probe(struct usb_interface *interface,
314 const struct usb_device_id *id)
315{
316 struct usb_lcd *dev = NULL;
317 struct usb_host_interface *iface_desc;
318 struct usb_endpoint_descriptor *endpoint;
319 size_t buffer_size;
320 int i;
321 int retval = -ENOMEM;
322
323
324 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
325 if (dev == NULL) {
326 dev_err(&interface->dev, "Out of memory\n");
327 goto error;
328 }
329 kref_init(&dev->kref);
330 sema_init(&dev->limit_sem, USB_LCD_CONCURRENT_WRITES);
331 init_usb_anchor(&dev->submitted);
332
333 dev->udev = usb_get_dev(interface_to_usbdev(interface));
334 dev->interface = interface;
335
336 if (le16_to_cpu(dev->udev->descriptor.idProduct) != 0x0001) {
337 dev_warn(&interface->dev, "USBLCD model not supported.\n");
338 retval = -ENODEV;
339 goto error;
340 }
341
342
343
344 iface_desc = interface->cur_altsetting;
345 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
346 endpoint = &iface_desc->endpoint[i].desc;
347
348 if (!dev->bulk_in_endpointAddr &&
349 usb_endpoint_is_bulk_in(endpoint)) {
350
351 buffer_size = usb_endpoint_maxp(endpoint);
352 dev->bulk_in_size = buffer_size;
353 dev->bulk_in_endpointAddr = endpoint->bEndpointAddress;
354 dev->bulk_in_buffer = kmalloc(buffer_size, GFP_KERNEL);
355 if (!dev->bulk_in_buffer) {
356 dev_err(&interface->dev,
357 "Could not allocate bulk_in_buffer\n");
358 goto error;
359 }
360 }
361
362 if (!dev->bulk_out_endpointAddr &&
363 usb_endpoint_is_bulk_out(endpoint)) {
364
365 dev->bulk_out_endpointAddr = endpoint->bEndpointAddress;
366 }
367 }
368 if (!(dev->bulk_in_endpointAddr && dev->bulk_out_endpointAddr)) {
369 dev_err(&interface->dev,
370 "Could not find both bulk-in and bulk-out endpoints\n");
371 goto error;
372 }
373
374
375 usb_set_intfdata(interface, dev);
376
377
378 retval = usb_register_dev(interface, &lcd_class);
379 if (retval) {
380
381 dev_err(&interface->dev,
382 "Not able to get a minor for this device.\n");
383 usb_set_intfdata(interface, NULL);
384 goto error;
385 }
386
387 i = le16_to_cpu(dev->udev->descriptor.bcdDevice);
388
389 dev_info(&interface->dev, "USBLCD Version %1d%1d.%1d%1d found "
390 "at address %d\n", (i & 0xF000)>>12, (i & 0xF00)>>8,
391 (i & 0xF0)>>4, (i & 0xF), dev->udev->devnum);
392
393
394 dev_info(&interface->dev, "USB LCD device now attached to USBLCD-%d\n",
395 interface->minor);
396 return 0;
397
398error:
399 if (dev)
400 kref_put(&dev->kref, lcd_delete);
401 return retval;
402}
403
404static void lcd_draw_down(struct usb_lcd *dev)
405{
406 int time;
407
408 time = usb_wait_anchor_empty_timeout(&dev->submitted, 1000);
409 if (!time)
410 usb_kill_anchored_urbs(&dev->submitted);
411}
412
413static int lcd_suspend(struct usb_interface *intf, pm_message_t message)
414{
415 struct usb_lcd *dev = usb_get_intfdata(intf);
416
417 if (!dev)
418 return 0;
419 lcd_draw_down(dev);
420 return 0;
421}
422
423static int lcd_resume(struct usb_interface *intf)
424{
425 return 0;
426}
427
428static void lcd_disconnect(struct usb_interface *interface)
429{
430 struct usb_lcd *dev;
431 int minor = interface->minor;
432
433 mutex_lock(&open_disc_mutex);
434 dev = usb_get_intfdata(interface);
435 usb_set_intfdata(interface, NULL);
436 mutex_unlock(&open_disc_mutex);
437
438
439 usb_deregister_dev(interface, &lcd_class);
440
441
442 kref_put(&dev->kref, lcd_delete);
443
444 dev_info(&interface->dev, "USB LCD #%d now disconnected\n", minor);
445}
446
447static struct usb_driver lcd_driver = {
448 .name = "usblcd",
449 .probe = lcd_probe,
450 .disconnect = lcd_disconnect,
451 .suspend = lcd_suspend,
452 .resume = lcd_resume,
453 .id_table = id_table,
454 .supports_autosuspend = 1,
455};
456
457module_usb_driver(lcd_driver);
458
459MODULE_AUTHOR("Georges Toth <g.toth@e-biz.lu>");
460MODULE_DESCRIPTION(DRIVER_VERSION);
461MODULE_LICENSE("GPL");
462
