1 // SPDX-License-Identifier: GPL-2.0+
3 * LEGO USB Tower driver
5 * Copyright (C) 2003 David Glance <davidgsf@sourceforge.net>
6 * 2001-2004 Juergen Stuber <starblue@users.sourceforge.net>
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of
11 * the License, or (at your option) any later version.
13 * derived from USB Skeleton driver - 0.5
14 * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
21 * - simplified buffering, one-shot URBs for writing
23 * - removed IOCTL (setting power/mode is more complicated, postponed)
25 * - added vendor commands for mode of operation and power level in open
27 * - set IR mode by default (by oversight 0.4 set VLL mode)
28 * 2002-01-11 - 0.5? pcchan
29 * - make read buffer reusable and work around bytes_to_write issue between
30 * uhci and legusbtower
31 * 2002-09-23 - 0.52 david (david@csse.uwa.edu.au)
32 * - imported into lejos project
33 * - changed wake_up to wake_up_interruptible
34 * - changed to use lego0 rather than tower0
35 * - changed dbg() to use __func__ rather than deprecated __func__
36 * 2003-01-12 - 0.53 david (david@csse.uwa.edu.au)
37 * - changed read and write to write everything or
38 * timeout (from a patch by Chris Riesen and Brett Thaeler driver)
39 * - added ioctl functionality to set timeouts
40 * 2003-07-18 - 0.54 davidgsf (david@csse.uwa.edu.au)
41 * - initial import into LegoUSB project
42 * - merge of existing LegoUSB.c driver
43 * 2003-07-18 - 0.56 davidgsf (david@csse.uwa.edu.au)
44 * - port to 2.6 style driver
45 * 2004-02-29 - 0.6 Juergen Stuber <starblue@users.sourceforge.net>
47 * - unlink read URBs which are no longer needed
48 * - allow increased buffer size, eliminates need for timeout on write
49 * - have read URB running continuously
52 * - added nonblocking I/O
53 * - changed back __func__ to __func__
54 * - read and log tower firmware version
55 * - reset tower on probe, avoids failure of first write
56 * 2004-03-09 - 0.7 Juergen Stuber <starblue@users.sourceforge.net>
57 * - timeout read now only after inactivity, shorten default accordingly
58 * 2004-03-11 - 0.8 Juergen Stuber <starblue@users.sourceforge.net>
59 * - log major, minor instead of possibly confusing device filename
60 * - whitespace cleanup
61 * 2004-03-12 - 0.9 Juergen Stuber <starblue@users.sourceforge.net>
62 * - normalize whitespace in debug messages
63 * - take care about endianness in control message responses
64 * 2004-03-13 - 0.91 Juergen Stuber <starblue@users.sourceforge.net>
65 * - make default intervals longer to accommodate current EHCI driver
66 * 2004-03-19 - 0.92 Juergen Stuber <starblue@users.sourceforge.net>
67 * - replaced atomic_t by memory barriers
68 * 2004-04-21 - 0.93 Juergen Stuber <starblue@users.sourceforge.net>
69 * - wait for completion of write urb in release (needed for remotecontrol)
70 * - corrected poll for write direction (missing negation)
71 * 2004-04-22 - 0.94 Juergen Stuber <starblue@users.sourceforge.net>
72 * - make device locking interruptible
73 * 2004-04-30 - 0.95 Juergen Stuber <starblue@users.sourceforge.net>
74 * - check for valid udev on resubmitting and unlinking urbs
75 * 2004-08-03 - 0.96 Juergen Stuber <starblue@users.sourceforge.net>
76 * - move reset into open to clean out spurious data
79 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
81 #include <linux/kernel.h>
82 #include <linux/errno.h>
83 #include <linux/slab.h>
84 #include <linux/module.h>
85 #include <linux/completion.h>
86 #include <linux/mutex.h>
87 #include <linux/uaccess.h>
88 #include <linux/usb.h>
89 #include <linux/poll.h>
92 #define DRIVER_AUTHOR "Juergen Stuber <starblue@sourceforge.net>"
93 #define DRIVER_DESC "LEGO USB Tower Driver"
96 /* The defaults are chosen to work with the latest versions of leJOS and NQC.
99 /* Some legacy software likes to receive packets in one piece.
100 * In this case read_buffer_size should exceed the maximal packet length
101 * (417 for datalog uploads), and packet_timeout should be set.
103 static int read_buffer_size
= 480;
104 module_param(read_buffer_size
, int, 0);
105 MODULE_PARM_DESC(read_buffer_size
, "Read buffer size");
107 /* Some legacy software likes to send packets in one piece.
108 * In this case write_buffer_size should exceed the maximal packet length
109 * (417 for firmware and program downloads).
110 * A problem with long writes is that the following read may time out
111 * if the software is not prepared to wait long enough.
113 static int write_buffer_size
= 480;
114 module_param(write_buffer_size
, int, 0);
115 MODULE_PARM_DESC(write_buffer_size
, "Write buffer size");
117 /* Some legacy software expects reads to contain whole LASM packets.
118 * To achieve this, characters which arrive before a packet timeout
119 * occurs will be returned in a single read operation.
120 * A problem with long reads is that the software may time out
121 * if it is not prepared to wait long enough.
122 * The packet timeout should be greater than the time between the
123 * reception of subsequent characters, which should arrive about
124 * every 5ms for the standard 2400 baud.
125 * Set it to 0 to disable.
127 static int packet_timeout
= 50;
128 module_param(packet_timeout
, int, 0);
129 MODULE_PARM_DESC(packet_timeout
, "Packet timeout in ms");
131 /* Some legacy software expects blocking reads to time out.
132 * Timeout occurs after the specified time of read and write inactivity.
133 * Set it to 0 to disable.
135 static int read_timeout
= 200;
136 module_param(read_timeout
, int, 0);
137 MODULE_PARM_DESC(read_timeout
, "Read timeout in ms");
139 /* As of kernel version 2.6.4 ehci-hcd uses an
140 * "only one interrupt transfer per frame" shortcut
141 * to simplify the scheduling of periodic transfers.
142 * This conflicts with our standard 1ms intervals for in and out URBs.
143 * We use default intervals of 2ms for in and 8ms for out transfers,
144 * which is fast enough for 2400 baud and allows a small additional load.
145 * Increase the interval to allow more devices that do interrupt transfers,
146 * or set to 0 to use the standard interval from the endpoint descriptors.
148 static int interrupt_in_interval
= 2;
149 module_param(interrupt_in_interval
, int, 0);
150 MODULE_PARM_DESC(interrupt_in_interval
, "Interrupt in interval in ms");
152 static int interrupt_out_interval
= 8;
153 module_param(interrupt_out_interval
, int, 0);
154 MODULE_PARM_DESC(interrupt_out_interval
, "Interrupt out interval in ms");
156 /* Define these values to match your device */
157 #define LEGO_USB_TOWER_VENDOR_ID 0x0694
158 #define LEGO_USB_TOWER_PRODUCT_ID 0x0001
160 /* Vendor requests */
161 #define LEGO_USB_TOWER_REQUEST_RESET 0x04
162 #define LEGO_USB_TOWER_REQUEST_GET_VERSION 0xFD
164 struct tower_reset_reply
{
165 __le16 size
; /* little-endian */
168 } __attribute__ ((packed
));
170 struct tower_get_version_reply
{
171 __le16 size
; /* little-endian */
176 __le16 build_no
; /* little-endian */
177 } __attribute__ ((packed
));
180 /* table of devices that work with this driver */
181 static const struct usb_device_id tower_table
[] = {
182 { USB_DEVICE(LEGO_USB_TOWER_VENDOR_ID
, LEGO_USB_TOWER_PRODUCT_ID
) },
183 { } /* Terminating entry */
186 MODULE_DEVICE_TABLE (usb
, tower_table
);
187 static DEFINE_MUTEX(open_disc_mutex
);
189 #define LEGO_USB_TOWER_MINOR_BASE 160
192 /* Structure to hold all of our device specific stuff */
193 struct lego_usb_tower
{
194 struct mutex lock
; /* locks this structure */
195 struct usb_device
* udev
; /* save off the usb device pointer */
196 unsigned char minor
; /* the starting minor number for this device */
198 int open_count
; /* number of times this port has been opened */
201 size_t read_buffer_length
; /* this much came in */
202 size_t read_packet_length
; /* this much will be returned on read */
203 spinlock_t read_buffer_lock
;
204 int packet_timeout_jiffies
;
205 unsigned long read_last_arrival
;
207 wait_queue_head_t read_wait
;
208 wait_queue_head_t write_wait
;
210 char* interrupt_in_buffer
;
211 struct usb_endpoint_descriptor
* interrupt_in_endpoint
;
212 struct urb
* interrupt_in_urb
;
213 int interrupt_in_interval
;
214 int interrupt_in_running
;
215 int interrupt_in_done
;
217 char* interrupt_out_buffer
;
218 struct usb_endpoint_descriptor
* interrupt_out_endpoint
;
219 struct urb
* interrupt_out_urb
;
220 int interrupt_out_interval
;
221 int interrupt_out_busy
;
226 /* local function prototypes */
227 static ssize_t
tower_read (struct file
*file
, char __user
*buffer
, size_t count
, loff_t
*ppos
);
228 static ssize_t
tower_write (struct file
*file
, const char __user
*buffer
, size_t count
, loff_t
*ppos
);
229 static inline void tower_delete (struct lego_usb_tower
*dev
);
230 static int tower_open (struct inode
*inode
, struct file
*file
);
231 static int tower_release (struct inode
*inode
, struct file
*file
);
232 static unsigned int tower_poll (struct file
*file
, poll_table
*wait
);
233 static loff_t
tower_llseek (struct file
*file
, loff_t off
, int whence
);
235 static void tower_abort_transfers (struct lego_usb_tower
*dev
);
236 static void tower_check_for_read_packet (struct lego_usb_tower
*dev
);
237 static void tower_interrupt_in_callback (struct urb
*urb
);
238 static void tower_interrupt_out_callback (struct urb
*urb
);
240 static int tower_probe (struct usb_interface
*interface
, const struct usb_device_id
*id
);
241 static void tower_disconnect (struct usb_interface
*interface
);
244 /* file operations needed when we register this driver */
245 static const struct file_operations tower_fops
= {
246 .owner
= THIS_MODULE
,
248 .write
= tower_write
,
250 .release
= tower_release
,
252 .llseek
= tower_llseek
,
255 static char *legousbtower_devnode(struct device
*dev
, umode_t
*mode
)
257 return kasprintf(GFP_KERNEL
, "usb/%s", dev_name(dev
));
261 * usb class driver info in order to get a minor number from the usb core,
262 * and to have the device registered with the driver core
264 static struct usb_class_driver tower_class
= {
265 .name
= "legousbtower%d",
266 .devnode
= legousbtower_devnode
,
268 .minor_base
= LEGO_USB_TOWER_MINOR_BASE
,
272 /* usb specific object needed to register this driver with the usb subsystem */
273 static struct usb_driver tower_driver
= {
274 .name
= "legousbtower",
275 .probe
= tower_probe
,
276 .disconnect
= tower_disconnect
,
277 .id_table
= tower_table
,
282 * lego_usb_tower_debug_data
284 static inline void lego_usb_tower_debug_data(struct device
*dev
,
285 const char *function
, int size
,
286 const unsigned char *data
)
288 dev_dbg(dev
, "%s - length = %d, data = %*ph\n",
289 function
, size
, size
, data
);
296 static inline void tower_delete (struct lego_usb_tower
*dev
)
298 tower_abort_transfers (dev
);
300 /* free data structures */
301 usb_free_urb(dev
->interrupt_in_urb
);
302 usb_free_urb(dev
->interrupt_out_urb
);
303 kfree (dev
->read_buffer
);
304 kfree (dev
->interrupt_in_buffer
);
305 kfree (dev
->interrupt_out_buffer
);
313 static int tower_open (struct inode
*inode
, struct file
*file
)
315 struct lego_usb_tower
*dev
= NULL
;
318 struct usb_interface
*interface
;
319 struct tower_reset_reply
*reset_reply
;
322 reset_reply
= kmalloc(sizeof(*reset_reply
), GFP_KERNEL
);
329 nonseekable_open(inode
, file
);
330 subminor
= iminor(inode
);
332 interface
= usb_find_interface (&tower_driver
, subminor
);
335 pr_err("error, can't find device for minor %d\n", subminor
);
340 mutex_lock(&open_disc_mutex
);
341 dev
= usb_get_intfdata(interface
);
344 mutex_unlock(&open_disc_mutex
);
349 /* lock this device */
350 if (mutex_lock_interruptible(&dev
->lock
)) {
351 mutex_unlock(&open_disc_mutex
);
352 retval
= -ERESTARTSYS
;
357 /* allow opening only once */
358 if (dev
->open_count
) {
359 mutex_unlock(&open_disc_mutex
);
364 mutex_unlock(&open_disc_mutex
);
366 /* reset the tower */
367 result
= usb_control_msg (dev
->udev
,
368 usb_rcvctrlpipe(dev
->udev
, 0),
369 LEGO_USB_TOWER_REQUEST_RESET
,
370 USB_TYPE_VENDOR
| USB_DIR_IN
| USB_RECIP_DEVICE
,
374 sizeof(*reset_reply
),
377 dev_err(&dev
->udev
->dev
,
378 "LEGO USB Tower reset control request failed\n");
383 /* initialize in direction */
384 dev
->read_buffer_length
= 0;
385 dev
->read_packet_length
= 0;
386 usb_fill_int_urb (dev
->interrupt_in_urb
,
388 usb_rcvintpipe(dev
->udev
, dev
->interrupt_in_endpoint
->bEndpointAddress
),
389 dev
->interrupt_in_buffer
,
390 usb_endpoint_maxp(dev
->interrupt_in_endpoint
),
391 tower_interrupt_in_callback
,
393 dev
->interrupt_in_interval
);
395 dev
->interrupt_in_running
= 1;
396 dev
->interrupt_in_done
= 0;
399 retval
= usb_submit_urb (dev
->interrupt_in_urb
, GFP_KERNEL
);
401 dev_err(&dev
->udev
->dev
,
402 "Couldn't submit interrupt_in_urb %d\n", retval
);
403 dev
->interrupt_in_running
= 0;
408 /* save device in the file's private structure */
409 file
->private_data
= dev
;
412 mutex_unlock(&dev
->lock
);
422 static int tower_release (struct inode
*inode
, struct file
*file
)
424 struct lego_usb_tower
*dev
;
427 dev
= file
->private_data
;
434 mutex_lock(&open_disc_mutex
);
435 if (mutex_lock_interruptible(&dev
->lock
)) {
436 retval
= -ERESTARTSYS
;
440 if (dev
->open_count
!= 1) {
441 dev_dbg(&dev
->udev
->dev
, "%s: device not opened exactly once\n",
446 if (dev
->udev
== NULL
) {
447 /* the device was unplugged before the file was released */
449 /* unlock here as tower_delete frees dev */
450 mutex_unlock(&dev
->lock
);
455 /* wait until write transfer is finished */
456 if (dev
->interrupt_out_busy
) {
457 wait_event_interruptible_timeout (dev
->write_wait
, !dev
->interrupt_out_busy
, 2 * HZ
);
459 tower_abort_transfers (dev
);
463 mutex_unlock(&dev
->lock
);
466 mutex_unlock(&open_disc_mutex
);
473 * tower_abort_transfers
474 * aborts transfers and frees associated data structures
476 static void tower_abort_transfers (struct lego_usb_tower
*dev
)
481 /* shutdown transfer */
482 if (dev
->interrupt_in_running
) {
483 dev
->interrupt_in_running
= 0;
486 usb_kill_urb (dev
->interrupt_in_urb
);
488 if (dev
->interrupt_out_busy
&& dev
->udev
)
489 usb_kill_urb(dev
->interrupt_out_urb
);
494 * tower_check_for_read_packet
496 * To get correct semantics for signals and non-blocking I/O
497 * with packetizing we pretend not to see any data in the read buffer
498 * until it has been there unchanged for at least
499 * dev->packet_timeout_jiffies, or until the buffer is full.
501 static void tower_check_for_read_packet (struct lego_usb_tower
*dev
)
503 spin_lock_irq (&dev
->read_buffer_lock
);
505 || time_after(jiffies
, dev
->read_last_arrival
+ dev
->packet_timeout_jiffies
)
506 || dev
->read_buffer_length
== read_buffer_size
) {
507 dev
->read_packet_length
= dev
->read_buffer_length
;
509 dev
->interrupt_in_done
= 0;
510 spin_unlock_irq (&dev
->read_buffer_lock
);
517 static unsigned int tower_poll (struct file
*file
, poll_table
*wait
)
519 struct lego_usb_tower
*dev
;
520 unsigned int mask
= 0;
522 dev
= file
->private_data
;
525 return POLLERR
| POLLHUP
;
527 poll_wait(file
, &dev
->read_wait
, wait
);
528 poll_wait(file
, &dev
->write_wait
, wait
);
530 tower_check_for_read_packet(dev
);
531 if (dev
->read_packet_length
> 0) {
532 mask
|= POLLIN
| POLLRDNORM
;
534 if (!dev
->interrupt_out_busy
) {
535 mask
|= POLLOUT
| POLLWRNORM
;
545 static loff_t
tower_llseek (struct file
*file
, loff_t off
, int whence
)
547 return -ESPIPE
; /* unseekable */
554 static ssize_t
tower_read (struct file
*file
, char __user
*buffer
, size_t count
, loff_t
*ppos
)
556 struct lego_usb_tower
*dev
;
557 size_t bytes_to_read
;
560 unsigned long timeout
= 0;
562 dev
= file
->private_data
;
564 /* lock this object */
565 if (mutex_lock_interruptible(&dev
->lock
)) {
566 retval
= -ERESTARTSYS
;
570 /* verify that the device wasn't unplugged */
571 if (dev
->udev
== NULL
) {
573 pr_err("No device or device unplugged %d\n", retval
);
577 /* verify that we actually have some data to read */
579 dev_dbg(&dev
->udev
->dev
, "read request of 0 bytes\n");
584 timeout
= jiffies
+ msecs_to_jiffies(read_timeout
);
588 tower_check_for_read_packet (dev
);
589 while (dev
->read_packet_length
== 0) {
590 if (file
->f_flags
& O_NONBLOCK
) {
594 retval
= wait_event_interruptible_timeout(dev
->read_wait
, dev
->interrupt_in_done
, dev
->packet_timeout_jiffies
);
599 /* reset read timeout during read or write activity */
601 && (dev
->read_buffer_length
|| dev
->interrupt_out_busy
)) {
602 timeout
= jiffies
+ msecs_to_jiffies(read_timeout
);
604 /* check for read timeout */
605 if (read_timeout
&& time_after (jiffies
, timeout
)) {
609 tower_check_for_read_packet (dev
);
612 /* copy the data from read_buffer into userspace */
613 bytes_to_read
= min(count
, dev
->read_packet_length
);
615 if (copy_to_user (buffer
, dev
->read_buffer
, bytes_to_read
)) {
620 spin_lock_irq (&dev
->read_buffer_lock
);
621 dev
->read_buffer_length
-= bytes_to_read
;
622 dev
->read_packet_length
-= bytes_to_read
;
623 for (i
=0; i
<dev
->read_buffer_length
; i
++) {
624 dev
->read_buffer
[i
] = dev
->read_buffer
[i
+bytes_to_read
];
626 spin_unlock_irq (&dev
->read_buffer_lock
);
628 retval
= bytes_to_read
;
631 /* unlock the device */
632 mutex_unlock(&dev
->lock
);
642 static ssize_t
tower_write (struct file
*file
, const char __user
*buffer
, size_t count
, loff_t
*ppos
)
644 struct lego_usb_tower
*dev
;
645 size_t bytes_to_write
;
648 dev
= file
->private_data
;
650 /* lock this object */
651 if (mutex_lock_interruptible(&dev
->lock
)) {
652 retval
= -ERESTARTSYS
;
656 /* verify that the device wasn't unplugged */
657 if (dev
->udev
== NULL
) {
659 pr_err("No device or device unplugged %d\n", retval
);
663 /* verify that we actually have some data to write */
665 dev_dbg(&dev
->udev
->dev
, "write request of 0 bytes\n");
669 /* wait until previous transfer is finished */
670 while (dev
->interrupt_out_busy
) {
671 if (file
->f_flags
& O_NONBLOCK
) {
675 retval
= wait_event_interruptible (dev
->write_wait
, !dev
->interrupt_out_busy
);
681 /* write the data into interrupt_out_buffer from userspace */
682 bytes_to_write
= min_t(int, count
, write_buffer_size
);
683 dev_dbg(&dev
->udev
->dev
, "%s: count = %zd, bytes_to_write = %zd\n",
684 __func__
, count
, bytes_to_write
);
686 if (copy_from_user (dev
->interrupt_out_buffer
, buffer
, bytes_to_write
)) {
691 /* send off the urb */
692 usb_fill_int_urb(dev
->interrupt_out_urb
,
694 usb_sndintpipe(dev
->udev
, dev
->interrupt_out_endpoint
->bEndpointAddress
),
695 dev
->interrupt_out_buffer
,
697 tower_interrupt_out_callback
,
699 dev
->interrupt_out_interval
);
701 dev
->interrupt_out_busy
= 1;
704 retval
= usb_submit_urb (dev
->interrupt_out_urb
, GFP_KERNEL
);
706 dev
->interrupt_out_busy
= 0;
707 dev_err(&dev
->udev
->dev
,
708 "Couldn't submit interrupt_out_urb %d\n", retval
);
711 retval
= bytes_to_write
;
714 /* unlock the device */
715 mutex_unlock(&dev
->lock
);
723 * tower_interrupt_in_callback
725 static void tower_interrupt_in_callback (struct urb
*urb
)
727 struct lego_usb_tower
*dev
= urb
->context
;
728 int status
= urb
->status
;
731 lego_usb_tower_debug_data(&dev
->udev
->dev
, __func__
,
732 urb
->actual_length
, urb
->transfer_buffer
);
735 if (status
== -ENOENT
||
736 status
== -ECONNRESET
||
737 status
== -ESHUTDOWN
) {
740 dev_dbg(&dev
->udev
->dev
,
741 "%s: nonzero status received: %d\n", __func__
,
743 goto resubmit
; /* maybe we can recover */
747 if (urb
->actual_length
> 0) {
748 spin_lock (&dev
->read_buffer_lock
);
749 if (dev
->read_buffer_length
+ urb
->actual_length
< read_buffer_size
) {
750 memcpy (dev
->read_buffer
+ dev
->read_buffer_length
,
751 dev
->interrupt_in_buffer
,
753 dev
->read_buffer_length
+= urb
->actual_length
;
754 dev
->read_last_arrival
= jiffies
;
755 dev_dbg(&dev
->udev
->dev
, "%s: received %d bytes\n",
756 __func__
, urb
->actual_length
);
758 pr_warn("read_buffer overflow, %d bytes dropped\n",
761 spin_unlock (&dev
->read_buffer_lock
);
765 /* resubmit if we're still running */
766 if (dev
->interrupt_in_running
&& dev
->udev
) {
767 retval
= usb_submit_urb (dev
->interrupt_in_urb
, GFP_ATOMIC
);
769 dev_err(&dev
->udev
->dev
,
770 "%s: usb_submit_urb failed (%d)\n",
775 dev
->interrupt_in_done
= 1;
776 wake_up_interruptible (&dev
->read_wait
);
781 * tower_interrupt_out_callback
783 static void tower_interrupt_out_callback (struct urb
*urb
)
785 struct lego_usb_tower
*dev
= urb
->context
;
786 int status
= urb
->status
;
788 lego_usb_tower_debug_data(&dev
->udev
->dev
, __func__
,
789 urb
->actual_length
, urb
->transfer_buffer
);
791 /* sync/async unlink faults aren't errors */
792 if (status
&& !(status
== -ENOENT
||
793 status
== -ECONNRESET
||
794 status
== -ESHUTDOWN
)) {
795 dev_dbg(&dev
->udev
->dev
,
796 "%s: nonzero write bulk status received: %d\n", __func__
,
800 dev
->interrupt_out_busy
= 0;
801 wake_up_interruptible(&dev
->write_wait
);
808 * Called by the usb core when a new device is connected that it thinks
809 * this driver might be interested in.
811 static int tower_probe (struct usb_interface
*interface
, const struct usb_device_id
*id
)
813 struct device
*idev
= &interface
->dev
;
814 struct usb_device
*udev
= interface_to_usbdev(interface
);
815 struct lego_usb_tower
*dev
= NULL
;
816 struct tower_get_version_reply
*get_version_reply
= NULL
;
817 int retval
= -ENOMEM
;
820 /* allocate memory for our device state and initialize it */
822 dev
= kmalloc (sizeof(struct lego_usb_tower
), GFP_KERNEL
);
827 mutex_init(&dev
->lock
);
832 dev
->read_buffer
= NULL
;
833 dev
->read_buffer_length
= 0;
834 dev
->read_packet_length
= 0;
835 spin_lock_init (&dev
->read_buffer_lock
);
836 dev
->packet_timeout_jiffies
= msecs_to_jiffies(packet_timeout
);
837 dev
->read_last_arrival
= jiffies
;
839 init_waitqueue_head (&dev
->read_wait
);
840 init_waitqueue_head (&dev
->write_wait
);
842 dev
->interrupt_in_buffer
= NULL
;
843 dev
->interrupt_in_endpoint
= NULL
;
844 dev
->interrupt_in_urb
= NULL
;
845 dev
->interrupt_in_running
= 0;
846 dev
->interrupt_in_done
= 0;
848 dev
->interrupt_out_buffer
= NULL
;
849 dev
->interrupt_out_endpoint
= NULL
;
850 dev
->interrupt_out_urb
= NULL
;
851 dev
->interrupt_out_busy
= 0;
853 result
= usb_find_common_endpoints_reverse(interface
->cur_altsetting
,
855 &dev
->interrupt_in_endpoint
,
856 &dev
->interrupt_out_endpoint
);
858 dev_err(idev
, "interrupt endpoints not found\n");
863 dev
->read_buffer
= kmalloc (read_buffer_size
, GFP_KERNEL
);
864 if (!dev
->read_buffer
)
866 dev
->interrupt_in_buffer
= kmalloc (usb_endpoint_maxp(dev
->interrupt_in_endpoint
), GFP_KERNEL
);
867 if (!dev
->interrupt_in_buffer
)
869 dev
->interrupt_in_urb
= usb_alloc_urb(0, GFP_KERNEL
);
870 if (!dev
->interrupt_in_urb
)
872 dev
->interrupt_out_buffer
= kmalloc (write_buffer_size
, GFP_KERNEL
);
873 if (!dev
->interrupt_out_buffer
)
875 dev
->interrupt_out_urb
= usb_alloc_urb(0, GFP_KERNEL
);
876 if (!dev
->interrupt_out_urb
)
878 dev
->interrupt_in_interval
= interrupt_in_interval
? interrupt_in_interval
: dev
->interrupt_in_endpoint
->bInterval
;
879 dev
->interrupt_out_interval
= interrupt_out_interval
? interrupt_out_interval
: dev
->interrupt_out_endpoint
->bInterval
;
881 get_version_reply
= kmalloc(sizeof(*get_version_reply
), GFP_KERNEL
);
883 if (!get_version_reply
) {
888 /* get the firmware version and log it */
889 result
= usb_control_msg (udev
,
890 usb_rcvctrlpipe(udev
, 0),
891 LEGO_USB_TOWER_REQUEST_GET_VERSION
,
892 USB_TYPE_VENDOR
| USB_DIR_IN
| USB_RECIP_DEVICE
,
896 sizeof(*get_version_reply
),
899 dev_err(idev
, "LEGO USB Tower get version control request failed\n");
903 dev_info(&interface
->dev
,
904 "LEGO USB Tower firmware version is %d.%d build %d\n",
905 get_version_reply
->major
,
906 get_version_reply
->minor
,
907 le16_to_cpu(get_version_reply
->build_no
));
909 /* we can register the device now, as it is ready */
910 usb_set_intfdata (interface
, dev
);
912 retval
= usb_register_dev (interface
, &tower_class
);
915 /* something prevented us from registering this driver */
916 dev_err(idev
, "Not able to get a minor for this device.\n");
917 usb_set_intfdata (interface
, NULL
);
920 dev
->minor
= interface
->minor
;
922 /* let the user know what node this device is now attached to */
923 dev_info(&interface
->dev
, "LEGO USB Tower #%d now attached to major "
924 "%d minor %d\n", (dev
->minor
- LEGO_USB_TOWER_MINOR_BASE
),
925 USB_MAJOR
, dev
->minor
);
928 kfree(get_version_reply
);
932 kfree(get_version_reply
);
941 * Called by the usb core when the device is removed from the system.
943 static void tower_disconnect (struct usb_interface
*interface
)
945 struct lego_usb_tower
*dev
;
948 dev
= usb_get_intfdata (interface
);
949 mutex_lock(&open_disc_mutex
);
950 usb_set_intfdata (interface
, NULL
);
954 /* give back our minor */
955 usb_deregister_dev (interface
, &tower_class
);
957 mutex_lock(&dev
->lock
);
958 mutex_unlock(&open_disc_mutex
);
960 /* if the device is not opened, then we clean up right now */
961 if (!dev
->open_count
) {
962 mutex_unlock(&dev
->lock
);
966 /* wake up pollers */
967 wake_up_interruptible_all(&dev
->read_wait
);
968 wake_up_interruptible_all(&dev
->write_wait
);
969 mutex_unlock(&dev
->lock
);
972 dev_info(&interface
->dev
, "LEGO USB Tower #%d now disconnected\n",
973 (minor
- LEGO_USB_TOWER_MINOR_BASE
));
976 module_usb_driver(tower_driver
);
978 MODULE_AUTHOR(DRIVER_AUTHOR
);
979 MODULE_DESCRIPTION(DRIVER_DESC
);
980 #ifdef MODULE_LICENSE
981 MODULE_LICENSE("GPL");