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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*****************************************************************************
2 * USBLCD Kernel Driver *
3 * Version 1.05 *
4 * (C) 2005 Georges Toth <g.toth@e-biz.lu> *
5 * *
6 * This file is licensed under the GPL. See COPYING in the package. *
7 * Based on usb-skeleton.c 2.0 by Greg Kroah-Hartman (greg@kroah.com) *
8 * *
9 * *
10 * 28.02.05 Complete rewrite of the original usblcd.c driver, *
11 * based on usb_skeleton.c. *
12 * This new driver allows more than one USB-LCD to be connected *
13 * and controlled, at once *
14 *****************************************************************************/
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>
Oliver Neukumd5d1cea2007-10-25 16:05:53 +020020#include <linux/mutex.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070021#include <asm/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
Arnd Bergmann925ce682010-07-11 23:18:56 +020032static DEFINE_MUTEX(lcd_mutex);
Németh Márton33b9e162010-01-10 15:34:45 +010033static const struct usb_device_id id_table[] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -070034 { .idVendor = 0x10D2, .match_flags = USB_DEVICE_ID_MATCH_VENDOR, },
35 { },
36};
37MODULE_DEVICE_TABLE (usb, id_table);
38
Oliver Neukumd5d1cea2007-10-25 16:05:53 +020039static DEFINE_MUTEX(open_disc_mutex);
40
Linus Torvalds1da177e2005-04-16 15:20:36 -070041
42struct usb_lcd {
43 struct usb_device * udev; /* init: probe_lcd */
44 struct usb_interface * interface; /* the interface for this device */
45 unsigned char * bulk_in_buffer; /* the buffer to receive data */
46 size_t bulk_in_size; /* the size of the receive buffer */
47 __u8 bulk_in_endpointAddr; /* the address of the bulk in endpoint */
48 __u8 bulk_out_endpointAddr; /* the address of the bulk out endpoint */
Oliver Neukum5afeb102007-06-11 15:36:02 +020049 struct kref kref;
50 struct semaphore limit_sem; /* to stop writes at full throttle from
51 * using up all RAM */
Oliver Neukum7bbe9902007-06-13 17:13:31 +020052 struct usb_anchor submitted; /* URBs to wait for before suspend */
Linus Torvalds1da177e2005-04-16 15:20:36 -070053};
54#define to_lcd_dev(d) container_of(d, struct usb_lcd, kref)
55
Oliver Neukum5afeb102007-06-11 15:36:02 +020056#define USB_LCD_CONCURRENT_WRITES 5
57
Linus Torvalds1da177e2005-04-16 15:20:36 -070058static struct usb_driver lcd_driver;
59
60
61static void lcd_delete(struct kref *kref)
62{
63 struct usb_lcd *dev = to_lcd_dev(kref);
64
65 usb_put_dev(dev->udev);
66 kfree (dev->bulk_in_buffer);
67 kfree (dev);
68}
69
70
71static int lcd_open(struct inode *inode, struct file *file)
72{
73 struct usb_lcd *dev;
74 struct usb_interface *interface;
Oliver Neukum7bbe9902007-06-13 17:13:31 +020075 int subminor, r;
Linus Torvalds1da177e2005-04-16 15:20:36 -070076
Arnd Bergmann925ce682010-07-11 23:18:56 +020077 mutex_lock(&lcd_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070078 subminor = iminor(inode);
79
80 interface = usb_find_interface(&lcd_driver, subminor);
81 if (!interface) {
Arnd Bergmann925ce682010-07-11 23:18:56 +020082 mutex_unlock(&lcd_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070083 err ("USBLCD: %s - error, can't find device for minor %d",
Harvey Harrison441b62c2008-03-03 16:08:34 -080084 __func__, subminor);
Alan Sternd4ead162007-05-22 11:46:41 -040085 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -070086 }
87
Oliver Neukumd5d1cea2007-10-25 16:05:53 +020088 mutex_lock(&open_disc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070089 dev = usb_get_intfdata(interface);
Oliver Neukumd5d1cea2007-10-25 16:05:53 +020090 if (!dev) {
91 mutex_unlock(&open_disc_mutex);
Arnd Bergmann925ce682010-07-11 23:18:56 +020092 mutex_unlock(&lcd_mutex);
Alan Sternd4ead162007-05-22 11:46:41 -040093 return -ENODEV;
Oliver Neukumd5d1cea2007-10-25 16:05:53 +020094 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070095
96 /* increment our usage count for the device */
97 kref_get(&dev->kref);
Oliver Neukumd5d1cea2007-10-25 16:05:53 +020098 mutex_unlock(&open_disc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070099
Oliver Neukum7bbe9902007-06-13 17:13:31 +0200100 /* grab a power reference */
101 r = usb_autopm_get_interface(interface);
102 if (r < 0) {
103 kref_put(&dev->kref, lcd_delete);
Arnd Bergmann925ce682010-07-11 23:18:56 +0200104 mutex_unlock(&lcd_mutex);
Oliver Neukum7bbe9902007-06-13 17:13:31 +0200105 return r;
106 }
107
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108 /* save our object in the file's private structure */
109 file->private_data = dev;
Arnd Bergmann925ce682010-07-11 23:18:56 +0200110 mutex_unlock(&lcd_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111
Alan Sternd4ead162007-05-22 11:46:41 -0400112 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113}
114
115static int lcd_release(struct inode *inode, struct file *file)
116{
117 struct usb_lcd *dev;
118
Joe Perches5bd6e8b2010-07-12 13:50:12 -0700119 dev = file->private_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120 if (dev == NULL)
121 return -ENODEV;
122
123 /* decrement the count on our device */
Oliver Neukum7bbe9902007-06-13 17:13:31 +0200124 usb_autopm_put_interface(dev->interface);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125 kref_put(&dev->kref, lcd_delete);
126 return 0;
127}
128
129static ssize_t lcd_read(struct file *file, char __user * buffer, size_t count, loff_t *ppos)
130{
131 struct usb_lcd *dev;
132 int retval = 0;
133 int bytes_read;
134
Joe Perches5bd6e8b2010-07-12 13:50:12 -0700135 dev = file->private_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136
137 /* do a blocking bulk read to get data from the device */
138 retval = usb_bulk_msg(dev->udev,
139 usb_rcvbulkpipe(dev->udev, dev->bulk_in_endpointAddr),
140 dev->bulk_in_buffer,
141 min(dev->bulk_in_size, count),
142 &bytes_read, 10000);
143
144 /* if the read was successful, copy the data to userspace */
145 if (!retval) {
146 if (copy_to_user(buffer, dev->bulk_in_buffer, bytes_read))
147 retval = -EFAULT;
148 else
149 retval = bytes_read;
150 }
151
152 return retval;
153}
154
Alan Cox5cb4aec2008-05-22 22:07:51 +0100155static long lcd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156{
157 struct usb_lcd *dev;
158 u16 bcdDevice;
159 char buf[30];
160
Joe Perches5bd6e8b2010-07-12 13:50:12 -0700161 dev = file->private_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162 if (dev == NULL)
163 return -ENODEV;
164
165 switch (cmd) {
166 case IOCTL_GET_HARD_VERSION:
Arnd Bergmann925ce682010-07-11 23:18:56 +0200167 mutex_lock(&lcd_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168 bcdDevice = le16_to_cpu((dev->udev)->descriptor.bcdDevice);
169 sprintf(buf,"%1d%1d.%1d%1d",
170 (bcdDevice & 0xF000)>>12,
171 (bcdDevice & 0xF00)>>8,
172 (bcdDevice & 0xF0)>>4,
173 (bcdDevice & 0xF));
Arnd Bergmann925ce682010-07-11 23:18:56 +0200174 mutex_unlock(&lcd_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175 if (copy_to_user((void __user *)arg,buf,strlen(buf))!=0)
176 return -EFAULT;
177 break;
178 case IOCTL_GET_DRV_VERSION:
179 sprintf(buf,DRIVER_VERSION);
180 if (copy_to_user((void __user *)arg,buf,strlen(buf))!=0)
181 return -EFAULT;
182 break;
183 default:
184 return -ENOTTY;
185 break;
186 }
187
188 return 0;
189}
190
David Howells7d12e782006-10-05 14:55:46 +0100191static void lcd_write_bulk_callback(struct urb *urb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700192{
193 struct usb_lcd *dev;
Greg Kroah-Hartman0723af12007-07-18 10:58:02 -0700194 int status = urb->status;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700195
Ming Leicdc97792008-02-24 18:41:47 +0800196 dev = urb->context;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197
198 /* sync/async unlink faults aren't errors */
Greg Kroah-Hartman0723af12007-07-18 10:58:02 -0700199 if (status &&
200 !(status == -ENOENT ||
201 status == -ECONNRESET ||
202 status == -ESHUTDOWN)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203 dbg("USBLCD: %s - nonzero write bulk status received: %d",
Harvey Harrison441b62c2008-03-03 16:08:34 -0800204 __func__, status);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700205 }
206
207 /* free up our allocated buffer */
Daniel Mack997ea582010-04-12 13:17:25 +0200208 usb_free_coherent(urb->dev, urb->transfer_buffer_length,
209 urb->transfer_buffer, urb->transfer_dma);
Oliver Neukum5afeb102007-06-11 15:36:02 +0200210 up(&dev->limit_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211}
212
213static ssize_t lcd_write(struct file *file, const char __user * user_buffer, size_t count, loff_t *ppos)
214{
215 struct usb_lcd *dev;
Oliver Neukum5afeb102007-06-11 15:36:02 +0200216 int retval = 0, r;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217 struct urb *urb = NULL;
218 char *buf = NULL;
219
Joe Perches5bd6e8b2010-07-12 13:50:12 -0700220 dev = file->private_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700221
222 /* verify that we actually have some data to write */
223 if (count == 0)
224 goto exit;
225
Oliver Neukum5afeb102007-06-11 15:36:02 +0200226 r = down_interruptible(&dev->limit_sem);
227 if (r < 0)
228 return -EINTR;
229
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230 /* create a urb, and a buffer for it, and copy the data to the urb */
231 urb = usb_alloc_urb(0, GFP_KERNEL);
Oliver Neukum5afeb102007-06-11 15:36:02 +0200232 if (!urb) {
233 retval = -ENOMEM;
234 goto err_no_buf;
235 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236
Daniel Mack997ea582010-04-12 13:17:25 +0200237 buf = usb_alloc_coherent(dev->udev, count, GFP_KERNEL, &urb->transfer_dma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700238 if (!buf) {
239 retval = -ENOMEM;
240 goto error;
241 }
242
243 if (copy_from_user(buf, user_buffer, count)) {
244 retval = -EFAULT;
245 goto error;
246 }
247
248 /* initialize the urb properly */
249 usb_fill_bulk_urb(urb, dev->udev,
250 usb_sndbulkpipe(dev->udev, dev->bulk_out_endpointAddr),
251 buf, count, lcd_write_bulk_callback, dev);
252 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
Oliver Neukum7bbe9902007-06-13 17:13:31 +0200253
254 usb_anchor_urb(urb, &dev->submitted);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255
256 /* send the data out the bulk port */
257 retval = usb_submit_urb(urb, GFP_KERNEL);
258 if (retval) {
Harvey Harrison441b62c2008-03-03 16:08:34 -0800259 err("USBLCD: %s - failed submitting write urb, error %d", __func__, retval);
Oliver Neukum7bbe9902007-06-13 17:13:31 +0200260 goto error_unanchor;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261 }
262
263 /* release our reference to this urb, the USB core will eventually free it entirely */
264 usb_free_urb(urb);
265
266exit:
267 return count;
Oliver Neukum7bbe9902007-06-13 17:13:31 +0200268error_unanchor:
269 usb_unanchor_urb(urb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700270error:
Daniel Mack997ea582010-04-12 13:17:25 +0200271 usb_free_coherent(dev->udev, count, buf, urb->transfer_dma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 usb_free_urb(urb);
Oliver Neukum5afeb102007-06-11 15:36:02 +0200273err_no_buf:
274 up(&dev->limit_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275 return retval;
276}
277
Luiz Fernando N. Capitulino066202d2006-08-05 20:37:11 -0300278static const struct file_operations lcd_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279 .owner = THIS_MODULE,
280 .read = lcd_read,
281 .write = lcd_write,
282 .open = lcd_open,
Alan Cox5cb4aec2008-05-22 22:07:51 +0100283 .unlocked_ioctl = lcd_ioctl,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284 .release = lcd_release,
Arnd Bergmann6038f372010-08-15 18:52:59 +0200285 .llseek = noop_llseek,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286};
287
288/*
Greg Kroah-Hartmand6e5bcf2005-06-20 21:15:16 -0700289 * usb class driver info in order to get a minor number from the usb core,
290 * and to have the device registered with the driver core
291 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292static struct usb_class_driver lcd_class = {
Greg Kroah-Hartmand6e5bcf2005-06-20 21:15:16 -0700293 .name = "lcd%d",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294 .fops = &lcd_fops,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295 .minor_base = USBLCD_MINOR,
296};
297
298static int lcd_probe(struct usb_interface *interface, const struct usb_device_id *id)
299{
300 struct usb_lcd *dev = NULL;
301 struct usb_host_interface *iface_desc;
302 struct usb_endpoint_descriptor *endpoint;
303 size_t buffer_size;
304 int i;
305 int retval = -ENOMEM;
306
307 /* allocate memory for our device state and initialize it */
Eric Sesterhenn80b6ca42006-02-27 21:29:43 +0100308 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309 if (dev == NULL) {
310 err("Out of memory");
311 goto error;
312 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313 kref_init(&dev->kref);
Oliver Neukum5afeb102007-06-11 15:36:02 +0200314 sema_init(&dev->limit_sem, USB_LCD_CONCURRENT_WRITES);
Oliver Neukum7bbe9902007-06-13 17:13:31 +0200315 init_usb_anchor(&dev->submitted);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316
317 dev->udev = usb_get_dev(interface_to_usbdev(interface));
318 dev->interface = interface;
319
320 if (le16_to_cpu(dev->udev->descriptor.idProduct) != 0x0001) {
Greg Kroah-Hartman3b6004f2008-08-14 09:37:34 -0700321 dev_warn(&interface->dev, "USBLCD model not supported.\n");
Jiri Slaby696a4ac2009-09-23 16:09:56 +0200322 retval = -ENODEV;
323 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324 }
325
326 /* set up the endpoint information */
327 /* use only the first bulk-in and bulk-out endpoints */
328 iface_desc = interface->cur_altsetting;
329 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
330 endpoint = &iface_desc->endpoint[i].desc;
331
332 if (!dev->bulk_in_endpointAddr &&
Luiz Fernando N. Capitulinob0b660b2006-09-27 11:58:54 -0700333 usb_endpoint_is_bulk_in(endpoint)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334 /* we found a bulk in endpoint */
335 buffer_size = le16_to_cpu(endpoint->wMaxPacketSize);
336 dev->bulk_in_size = buffer_size;
337 dev->bulk_in_endpointAddr = endpoint->bEndpointAddress;
338 dev->bulk_in_buffer = kmalloc(buffer_size, GFP_KERNEL);
339 if (!dev->bulk_in_buffer) {
340 err("Could not allocate bulk_in_buffer");
341 goto error;
342 }
343 }
344
345 if (!dev->bulk_out_endpointAddr &&
Luiz Fernando N. Capitulinob0b660b2006-09-27 11:58:54 -0700346 usb_endpoint_is_bulk_out(endpoint)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700347 /* we found a bulk out endpoint */
348 dev->bulk_out_endpointAddr = endpoint->bEndpointAddress;
349 }
350 }
351 if (!(dev->bulk_in_endpointAddr && dev->bulk_out_endpointAddr)) {
352 err("Could not find both bulk-in and bulk-out endpoints");
353 goto error;
354 }
355
356 /* save our data pointer in this interface device */
357 usb_set_intfdata(interface, dev);
358
359 /* we can register the device now, as it is ready */
360 retval = usb_register_dev(interface, &lcd_class);
361 if (retval) {
362 /* something prevented us from registering this driver */
363 err("Not able to get a minor for this device.");
364 usb_set_intfdata(interface, NULL);
365 goto error;
366 }
367
368 i = le16_to_cpu(dev->udev->descriptor.bcdDevice);
369
Greg Kroah-Hartman1b29a372008-08-18 13:21:04 -0700370 dev_info(&interface->dev, "USBLCD Version %1d%1d.%1d%1d found "
371 "at address %d\n", (i & 0xF000)>>12, (i & 0xF00)>>8,
372 (i & 0xF0)>>4,(i & 0xF), dev->udev->devnum);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373
374 /* let the user know what node this device is now attached to */
Greg Kroah-Hartman1b29a372008-08-18 13:21:04 -0700375 dev_info(&interface->dev, "USB LCD device now attached to USBLCD-%d\n",
376 interface->minor);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377 return 0;
378
379error:
380 if (dev)
381 kref_put(&dev->kref, lcd_delete);
382 return retval;
383}
384
Oliver Neukum7bbe9902007-06-13 17:13:31 +0200385static void lcd_draw_down(struct usb_lcd *dev)
386{
387 int time;
388
389 time = usb_wait_anchor_empty_timeout(&dev->submitted, 1000);
390 if (!time)
391 usb_kill_anchored_urbs(&dev->submitted);
392}
393
394static int lcd_suspend(struct usb_interface *intf, pm_message_t message)
395{
396 struct usb_lcd *dev = usb_get_intfdata(intf);
397
398 if (!dev)
399 return 0;
400 lcd_draw_down(dev);
401 return 0;
402}
403
404static int lcd_resume (struct usb_interface *intf)
405{
406 return 0;
407}
408
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409static void lcd_disconnect(struct usb_interface *interface)
410{
411 struct usb_lcd *dev;
412 int minor = interface->minor;
413
Oliver Neukumd5d1cea2007-10-25 16:05:53 +0200414 mutex_lock(&open_disc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415 dev = usb_get_intfdata(interface);
416 usb_set_intfdata(interface, NULL);
Oliver Neukumd5d1cea2007-10-25 16:05:53 +0200417 mutex_unlock(&open_disc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700418
419 /* give back our minor */
420 usb_deregister_dev(interface, &lcd_class);
421
Linus Torvalds1da177e2005-04-16 15:20:36 -0700422 /* decrement our usage count */
423 kref_put(&dev->kref, lcd_delete);
424
Greg Kroah-Hartman1b29a372008-08-18 13:21:04 -0700425 dev_info(&interface->dev, "USB LCD #%d now disconnected\n", minor);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426}
427
428static struct usb_driver lcd_driver = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700429 .name = "usblcd",
430 .probe = lcd_probe,
431 .disconnect = lcd_disconnect,
Oliver Neukum7bbe9902007-06-13 17:13:31 +0200432 .suspend = lcd_suspend,
433 .resume = lcd_resume,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434 .id_table = id_table,
Oliver Neukum7bbe9902007-06-13 17:13:31 +0200435 .supports_autosuspend = 1,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436};
437
438static int __init usb_lcd_init(void)
439{
440 int result;
441
442 result = usb_register(&lcd_driver);
443 if (result)
444 err("usb_register failed. Error number %d", result);
445
446 return result;
447}
448
449
450static void __exit usb_lcd_exit(void)
451{
452 usb_deregister(&lcd_driver);
453}
454
455module_init(usb_lcd_init);
456module_exit(usb_lcd_exit);
457
458MODULE_AUTHOR("Georges Toth <g.toth@e-biz.lu>");
459MODULE_DESCRIPTION(DRIVER_VERSION);
460MODULE_LICENSE("GPL");