xref: /linux/drivers/char/xilinx_hwicap/xilinx_hwicap.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 /*****************************************************************************
2  *
3  *     Author: Xilinx, Inc.
4  *
5  *     This program is free software; you can redistribute it and/or modify it
6  *     under the terms of the GNU General Public License as published by the
7  *     Free Software Foundation; either version 2 of the License, or (at your
8  *     option) any later version.
9  *
10  *     XILINX IS PROVIDING THIS DESIGN, CODE, OR INFORMATION "AS IS"
11  *     AS A COURTESY TO YOU, SOLELY FOR USE IN DEVELOPING PROGRAMS AND
12  *     SOLUTIONS FOR XILINX DEVICES.  BY PROVIDING THIS DESIGN, CODE,
13  *     OR INFORMATION AS ONE POSSIBLE IMPLEMENTATION OF THIS FEATURE,
14  *     APPLICATION OR STANDARD, XILINX IS MAKING NO REPRESENTATION
15  *     THAT THIS IMPLEMENTATION IS FREE FROM ANY CLAIMS OF INFRINGEMENT,
16  *     AND YOU ARE RESPONSIBLE FOR OBTAINING ANY RIGHTS YOU MAY REQUIRE
17  *     FOR YOUR IMPLEMENTATION.  XILINX EXPRESSLY DISCLAIMS ANY
18  *     WARRANTY WHATSOEVER WITH RESPECT TO THE ADEQUACY OF THE
19  *     IMPLEMENTATION, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OR
20  *     REPRESENTATIONS THAT THIS IMPLEMENTATION IS FREE FROM CLAIMS OF
21  *     INFRINGEMENT, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
22  *     FOR A PARTICULAR PURPOSE.
23  *
24  *     (c) Copyright 2002 Xilinx Inc., Systems Engineering Group
25  *     (c) Copyright 2004 Xilinx Inc., Systems Engineering Group
26  *     (c) Copyright 2007-2008 Xilinx Inc.
27  *     All rights reserved.
28  *
29  *     You should have received a copy of the GNU General Public License along
30  *     with this program; if not, write to the Free Software Foundation, Inc.,
31  *     675 Mass Ave, Cambridge, MA 02139, USA.
32  *
33  *****************************************************************************/
34 
35 /*
36  * This is the code behind /dev/icap* -- it allows a user-space
37  * application to use the Xilinx ICAP subsystem.
38  *
39  * The following operations are possible:
40  *
41  * open         open the port and initialize for access.
42  * release      release port
43  * write        Write a bitstream to the configuration processor.
44  * read         Read a data stream from the configuration processor.
45  *
46  * After being opened, the port is initialized and accessed to avoid a
47  * corrupted first read which may occur with some hardware.  The port
48  * is left in a desynched state, requiring that a synch sequence be
49  * transmitted before any valid configuration data.  A user will have
50  * exclusive access to the device while it remains open, and the state
51  * of the ICAP cannot be guaranteed after the device is closed.  Note
52  * that a complete reset of the core and the state of the ICAP cannot
53  * be performed on many versions of the cores, hence users of this
54  * device should avoid making inconsistent accesses to the device.  In
55  * particular, accessing the read interface, without first generating
56  * a write containing a readback packet can leave the ICAP in an
57  * inaccessible state.
58  *
59  * Note that in order to use the read interface, it is first necessary
60  * to write a request packet to the write interface.  i.e., it is not
61  * possible to simply readback the bitstream (or any configuration
62  * bits) from a device without specifically requesting them first.
63  * The code to craft such packets is intended to be part of the
64  * user-space application code that uses this device.  The simplest
65  * way to use this interface is simply:
66  *
67  * cp foo.bit /dev/icap0
68  *
69  * Note that unless foo.bit is an appropriately constructed partial
70  * bitstream, this has a high likelihood of overwriting the design
71  * currently programmed in the FPGA.
72  */
73 
74 #include <linux/module.h>
75 #include <linux/kernel.h>
76 #include <linux/types.h>
77 #include <linux/ioport.h>
78 #include <linux/interrupt.h>
79 #include <linux/fcntl.h>
80 #include <linux/init.h>
81 #include <linux/poll.h>
82 #include <linux/proc_fs.h>
83 #include <linux/mutex.h>
84 #include <linux/sysctl.h>
85 #include <linux/fs.h>
86 #include <linux/cdev.h>
87 #include <linux/of.h>
88 #include <linux/platform_device.h>
89 #include <linux/property.h>
90 #include <linux/slab.h>
91 #include <linux/io.h>
92 #include <linux/uaccess.h>
93 
94 #include "xilinx_hwicap.h"
95 #include "buffer_icap.h"
96 #include "fifo_icap.h"
97 
98 #define DRIVER_NAME "icap"
99 
100 #define HWICAP_REGS   (0x10000)
101 
102 #define XHWICAP_MAJOR 259
103 #define XHWICAP_MINOR 0
104 #define HWICAP_DEVICES 1
105 
106 /* An array, which is set to true when the device is registered. */
107 static DEFINE_MUTEX(hwicap_mutex);
108 static bool probed_devices[HWICAP_DEVICES];
109 static struct mutex icap_sem;
110 
111 static const struct class icap_class = {
112 	.name = "xilinx_config",
113 };
114 
115 #define UNIMPLEMENTED 0xFFFF
116 
117 static const struct config_registers v2_config_registers = {
118 	.CRC = 0,
119 	.FAR = 1,
120 	.FDRI = 2,
121 	.FDRO = 3,
122 	.CMD = 4,
123 	.CTL = 5,
124 	.MASK = 6,
125 	.STAT = 7,
126 	.LOUT = 8,
127 	.COR = 9,
128 	.MFWR = 10,
129 	.FLR = 11,
130 	.KEY = 12,
131 	.CBC = 13,
132 	.IDCODE = 14,
133 	.AXSS = UNIMPLEMENTED,
134 	.C0R_1 = UNIMPLEMENTED,
135 	.CSOB = UNIMPLEMENTED,
136 	.WBSTAR = UNIMPLEMENTED,
137 	.TIMER = UNIMPLEMENTED,
138 	.BOOTSTS = UNIMPLEMENTED,
139 	.CTL_1 = UNIMPLEMENTED,
140 };
141 
142 static const struct config_registers v4_config_registers = {
143 	.CRC = 0,
144 	.FAR = 1,
145 	.FDRI = 2,
146 	.FDRO = 3,
147 	.CMD = 4,
148 	.CTL = 5,
149 	.MASK = 6,
150 	.STAT = 7,
151 	.LOUT = 8,
152 	.COR = 9,
153 	.MFWR = 10,
154 	.FLR = UNIMPLEMENTED,
155 	.KEY = UNIMPLEMENTED,
156 	.CBC = 11,
157 	.IDCODE = 12,
158 	.AXSS = 13,
159 	.C0R_1 = UNIMPLEMENTED,
160 	.CSOB = UNIMPLEMENTED,
161 	.WBSTAR = UNIMPLEMENTED,
162 	.TIMER = UNIMPLEMENTED,
163 	.BOOTSTS = UNIMPLEMENTED,
164 	.CTL_1 = UNIMPLEMENTED,
165 };
166 
167 static const struct config_registers v5_config_registers = {
168 	.CRC = 0,
169 	.FAR = 1,
170 	.FDRI = 2,
171 	.FDRO = 3,
172 	.CMD = 4,
173 	.CTL = 5,
174 	.MASK = 6,
175 	.STAT = 7,
176 	.LOUT = 8,
177 	.COR = 9,
178 	.MFWR = 10,
179 	.FLR = UNIMPLEMENTED,
180 	.KEY = UNIMPLEMENTED,
181 	.CBC = 11,
182 	.IDCODE = 12,
183 	.AXSS = 13,
184 	.C0R_1 = 14,
185 	.CSOB = 15,
186 	.WBSTAR = 16,
187 	.TIMER = 17,
188 	.BOOTSTS = 18,
189 	.CTL_1 = 19,
190 };
191 
192 static const struct config_registers v6_config_registers = {
193 	.CRC = 0,
194 	.FAR = 1,
195 	.FDRI = 2,
196 	.FDRO = 3,
197 	.CMD = 4,
198 	.CTL = 5,
199 	.MASK = 6,
200 	.STAT = 7,
201 	.LOUT = 8,
202 	.COR = 9,
203 	.MFWR = 10,
204 	.FLR = UNIMPLEMENTED,
205 	.KEY = UNIMPLEMENTED,
206 	.CBC = 11,
207 	.IDCODE = 12,
208 	.AXSS = 13,
209 	.C0R_1 = 14,
210 	.CSOB = 15,
211 	.WBSTAR = 16,
212 	.TIMER = 17,
213 	.BOOTSTS = 22,
214 	.CTL_1 = 24,
215 };
216 
217 /**
218  * hwicap_command_desync - Send a DESYNC command to the ICAP port.
219  * @drvdata: a pointer to the drvdata.
220  *
221  * Returns: '0' on success and failure value on error
222  *
223  * This command desynchronizes the ICAP After this command, a
224  * bitstream containing a NULL packet, followed by a SYNCH packet is
225  * required before the ICAP will recognize commands.
226  */
227 static int hwicap_command_desync(struct hwicap_drvdata *drvdata)
228 {
229 	u32 buffer[4];
230 	u32 index = 0;
231 
232 	/*
233 	 * Create the data to be written to the ICAP.
234 	 */
235 	buffer[index++] = hwicap_type_1_write(drvdata->config_regs->CMD) | 1;
236 	buffer[index++] = XHI_CMD_DESYNCH;
237 	buffer[index++] = XHI_NOOP_PACKET;
238 	buffer[index++] = XHI_NOOP_PACKET;
239 
240 	/*
241 	 * Write the data to the FIFO and initiate the transfer of data present
242 	 * in the FIFO to the ICAP device.
243 	 */
244 	return drvdata->config->set_configuration(drvdata,
245 			&buffer[0], index);
246 }
247 
248 /**
249  * hwicap_get_configuration_register - Query a configuration register.
250  * @drvdata: a pointer to the drvdata.
251  * @reg: a constant which represents the configuration
252  * register value to be returned.
253  * Examples: XHI_IDCODE, XHI_FLR.
254  * @reg_data: returns the value of the register.
255  *
256  * Returns: '0' on success and failure value on error
257  *
258  * Sends a query packet to the ICAP and then receives the response.
259  * The icap is left in Synched state.
260  */
261 static int hwicap_get_configuration_register(struct hwicap_drvdata *drvdata,
262 		u32 reg, u32 *reg_data)
263 {
264 	int status;
265 	u32 buffer[6];
266 	u32 index = 0;
267 
268 	/*
269 	 * Create the data to be written to the ICAP.
270 	 */
271 	buffer[index++] = XHI_DUMMY_PACKET;
272 	buffer[index++] = XHI_NOOP_PACKET;
273 	buffer[index++] = XHI_SYNC_PACKET;
274 	buffer[index++] = XHI_NOOP_PACKET;
275 	buffer[index++] = XHI_NOOP_PACKET;
276 
277 	/*
278 	 * Write the data to the FIFO and initiate the transfer of data present
279 	 * in the FIFO to the ICAP device.
280 	 */
281 	status = drvdata->config->set_configuration(drvdata,
282 						    &buffer[0], index);
283 	if (status)
284 		return status;
285 
286 	/* If the syncword was not found, then we need to start over. */
287 	status = drvdata->config->get_status(drvdata);
288 	if ((status & XHI_SR_DALIGN_MASK) != XHI_SR_DALIGN_MASK)
289 		return -EIO;
290 
291 	index = 0;
292 	buffer[index++] = hwicap_type_1_read(reg) | 1;
293 	buffer[index++] = XHI_NOOP_PACKET;
294 	buffer[index++] = XHI_NOOP_PACKET;
295 
296 	/*
297 	 * Write the data to the FIFO and initiate the transfer of data present
298 	 * in the FIFO to the ICAP device.
299 	 */
300 	status = drvdata->config->set_configuration(drvdata,
301 			&buffer[0], index);
302 	if (status)
303 		return status;
304 
305 	/*
306 	 * Read the configuration register
307 	 */
308 	status = drvdata->config->get_configuration(drvdata, reg_data, 1);
309 	if (status)
310 		return status;
311 
312 	return 0;
313 }
314 
315 static int hwicap_initialize_hwicap(struct hwicap_drvdata *drvdata)
316 {
317 	int status;
318 	u32 idcode;
319 
320 	dev_dbg(drvdata->dev, "initializing\n");
321 
322 	/* Abort any current transaction, to make sure we have the
323 	 * ICAP in a good state.
324 	 */
325 	dev_dbg(drvdata->dev, "Reset...\n");
326 	drvdata->config->reset(drvdata);
327 
328 	dev_dbg(drvdata->dev, "Desync...\n");
329 	status = hwicap_command_desync(drvdata);
330 	if (status)
331 		return status;
332 
333 	/* Attempt to read the IDCODE from ICAP.  This
334 	 * may not be returned correctly, due to the design of the
335 	 * hardware.
336 	 */
337 	dev_dbg(drvdata->dev, "Reading IDCODE...\n");
338 	status = hwicap_get_configuration_register(
339 			drvdata, drvdata->config_regs->IDCODE, &idcode);
340 	dev_dbg(drvdata->dev, "IDCODE = %x\n", idcode);
341 	if (status)
342 		return status;
343 
344 	dev_dbg(drvdata->dev, "Desync...\n");
345 	status = hwicap_command_desync(drvdata);
346 	if (status)
347 		return status;
348 
349 	return 0;
350 }
351 
352 static ssize_t
353 hwicap_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
354 {
355 	struct hwicap_drvdata *drvdata = file->private_data;
356 	ssize_t bytes_to_read = 0;
357 	u32 *kbuf;
358 	u32 words;
359 	u32 bytes_remaining;
360 	int status;
361 
362 	status = mutex_lock_interruptible(&drvdata->sem);
363 	if (status)
364 		return status;
365 
366 	if (drvdata->read_buffer_in_use) {
367 		/* If there are leftover bytes in the buffer, just */
368 		/* return them and don't try to read more from the */
369 		/* ICAP device. */
370 		bytes_to_read =
371 			(count < drvdata->read_buffer_in_use) ? count :
372 			drvdata->read_buffer_in_use;
373 
374 		/* Return the data currently in the read buffer. */
375 		if (copy_to_user(buf, drvdata->read_buffer, bytes_to_read)) {
376 			status = -EFAULT;
377 			goto error;
378 		}
379 		drvdata->read_buffer_in_use -= bytes_to_read;
380 		memmove(drvdata->read_buffer,
381 		       drvdata->read_buffer + bytes_to_read,
382 		       4 - bytes_to_read);
383 	} else {
384 		/* Get new data from the ICAP, and return what was requested. */
385 		kbuf = (u32 *) get_zeroed_page(GFP_KERNEL);
386 		if (!kbuf) {
387 			status = -ENOMEM;
388 			goto error;
389 		}
390 
391 		/* The ICAP device is only able to read complete */
392 		/* words.  If a number of bytes that do not correspond */
393 		/* to complete words is requested, then we read enough */
394 		/* words to get the required number of bytes, and then */
395 		/* save the remaining bytes for the next read. */
396 
397 		/* Determine the number of words to read, rounding up */
398 		/* if necessary. */
399 		words = ((count + 3) >> 2);
400 		bytes_to_read = words << 2;
401 
402 		if (bytes_to_read > PAGE_SIZE)
403 			bytes_to_read = PAGE_SIZE;
404 
405 		/* Ensure we only read a complete number of words. */
406 		bytes_remaining = bytes_to_read & 3;
407 		bytes_to_read &= ~3;
408 		words = bytes_to_read >> 2;
409 
410 		status = drvdata->config->get_configuration(drvdata,
411 				kbuf, words);
412 
413 		/* If we didn't read correctly, then bail out. */
414 		if (status) {
415 			free_page((unsigned long)kbuf);
416 			goto error;
417 		}
418 
419 		/* If we fail to return the data to the user, then bail out. */
420 		if (copy_to_user(buf, kbuf, bytes_to_read)) {
421 			free_page((unsigned long)kbuf);
422 			status = -EFAULT;
423 			goto error;
424 		}
425 		memcpy(drvdata->read_buffer,
426 		       kbuf,
427 		       bytes_remaining);
428 		drvdata->read_buffer_in_use = bytes_remaining;
429 		free_page((unsigned long)kbuf);
430 	}
431 	status = bytes_to_read;
432  error:
433 	mutex_unlock(&drvdata->sem);
434 	return status;
435 }
436 
437 static ssize_t
438 hwicap_write(struct file *file, const char __user *buf,
439 		size_t count, loff_t *ppos)
440 {
441 	struct hwicap_drvdata *drvdata = file->private_data;
442 	ssize_t written = 0;
443 	ssize_t left = count;
444 	u32 *kbuf;
445 	ssize_t len;
446 	ssize_t status;
447 
448 	status = mutex_lock_interruptible(&drvdata->sem);
449 	if (status)
450 		return status;
451 
452 	left += drvdata->write_buffer_in_use;
453 
454 	/* Only write multiples of 4 bytes. */
455 	if (left < 4) {
456 		status = 0;
457 		goto error;
458 	}
459 
460 	kbuf = (u32 *) __get_free_page(GFP_KERNEL);
461 	if (!kbuf) {
462 		status = -ENOMEM;
463 		goto error;
464 	}
465 
466 	while (left > 3) {
467 		/* only write multiples of 4 bytes, so there might */
468 		/* be as many as 3 bytes left (at the end). */
469 		len = left;
470 
471 		if (len > PAGE_SIZE)
472 			len = PAGE_SIZE;
473 		len &= ~3;
474 
475 		if (drvdata->write_buffer_in_use) {
476 			memcpy(kbuf, drvdata->write_buffer,
477 					drvdata->write_buffer_in_use);
478 			if (copy_from_user(
479 			    (((char *)kbuf) + drvdata->write_buffer_in_use),
480 			    buf + written,
481 			    len - (drvdata->write_buffer_in_use))) {
482 				free_page((unsigned long)kbuf);
483 				status = -EFAULT;
484 				goto error;
485 			}
486 		} else {
487 			if (copy_from_user(kbuf, buf + written, len)) {
488 				free_page((unsigned long)kbuf);
489 				status = -EFAULT;
490 				goto error;
491 			}
492 		}
493 
494 		status = drvdata->config->set_configuration(drvdata,
495 				kbuf, len >> 2);
496 
497 		if (status) {
498 			free_page((unsigned long)kbuf);
499 			status = -EFAULT;
500 			goto error;
501 		}
502 		if (drvdata->write_buffer_in_use) {
503 			len -= drvdata->write_buffer_in_use;
504 			left -= drvdata->write_buffer_in_use;
505 			drvdata->write_buffer_in_use = 0;
506 		}
507 		written += len;
508 		left -= len;
509 	}
510 	if ((left > 0) && (left < 4)) {
511 		if (!copy_from_user(drvdata->write_buffer,
512 						buf + written, left)) {
513 			drvdata->write_buffer_in_use = left;
514 			written += left;
515 			left = 0;
516 		}
517 	}
518 
519 	free_page((unsigned long)kbuf);
520 	status = written;
521  error:
522 	mutex_unlock(&drvdata->sem);
523 	return status;
524 }
525 
526 static int hwicap_open(struct inode *inode, struct file *file)
527 {
528 	struct hwicap_drvdata *drvdata;
529 	int status;
530 
531 	mutex_lock(&hwicap_mutex);
532 	drvdata = container_of(inode->i_cdev, struct hwicap_drvdata, cdev);
533 
534 	status = mutex_lock_interruptible(&drvdata->sem);
535 	if (status)
536 		goto out;
537 
538 	if (drvdata->is_open) {
539 		status = -EBUSY;
540 		goto error;
541 	}
542 
543 	status = hwicap_initialize_hwicap(drvdata);
544 	if (status) {
545 		dev_err(drvdata->dev, "Failed to open file");
546 		goto error;
547 	}
548 
549 	file->private_data = drvdata;
550 	drvdata->write_buffer_in_use = 0;
551 	drvdata->read_buffer_in_use = 0;
552 	drvdata->is_open = 1;
553 
554  error:
555 	mutex_unlock(&drvdata->sem);
556  out:
557 	mutex_unlock(&hwicap_mutex);
558 	return status;
559 }
560 
561 static int hwicap_release(struct inode *inode, struct file *file)
562 {
563 	struct hwicap_drvdata *drvdata = file->private_data;
564 	int i;
565 	int status = 0;
566 
567 	mutex_lock(&drvdata->sem);
568 
569 	if (drvdata->write_buffer_in_use) {
570 		/* Flush write buffer. */
571 		for (i = drvdata->write_buffer_in_use; i < 4; i++)
572 			drvdata->write_buffer[i] = 0;
573 
574 		status = drvdata->config->set_configuration(drvdata,
575 				(u32 *) drvdata->write_buffer, 1);
576 		if (status)
577 			goto error;
578 	}
579 
580 	status = hwicap_command_desync(drvdata);
581 	if (status)
582 		goto error;
583 
584  error:
585 	drvdata->is_open = 0;
586 	mutex_unlock(&drvdata->sem);
587 	return status;
588 }
589 
590 static const struct file_operations hwicap_fops = {
591 	.owner = THIS_MODULE,
592 	.write = hwicap_write,
593 	.read = hwicap_read,
594 	.open = hwicap_open,
595 	.release = hwicap_release,
596 	.llseek = noop_llseek,
597 };
598 
599 static int hwicap_setup(struct platform_device *pdev, int id,
600 		const struct hwicap_driver_config *config,
601 		const struct config_registers *config_regs)
602 {
603 	dev_t devt;
604 	struct hwicap_drvdata *drvdata = NULL;
605 	struct device *dev = &pdev->dev;
606 	int retval;
607 
608 	dev_info(dev, "Xilinx icap port driver\n");
609 
610 	mutex_lock(&icap_sem);
611 
612 	if (id < 0) {
613 		for (id = 0; id < HWICAP_DEVICES; id++)
614 			if (!probed_devices[id])
615 				break;
616 	}
617 	if (id < 0 || id >= HWICAP_DEVICES) {
618 		mutex_unlock(&icap_sem);
619 		dev_err(dev, "%s%i too large\n", DRIVER_NAME, id);
620 		return -EINVAL;
621 	}
622 	if (probed_devices[id]) {
623 		mutex_unlock(&icap_sem);
624 		dev_err(dev, "cannot assign to %s%i; it is already in use\n",
625 			DRIVER_NAME, id);
626 		return -EBUSY;
627 	}
628 
629 	probed_devices[id] = 1;
630 	mutex_unlock(&icap_sem);
631 
632 	devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR + id);
633 
634 	drvdata = devm_kzalloc(dev, sizeof(struct hwicap_drvdata), GFP_KERNEL);
635 	if (!drvdata) {
636 		retval = -ENOMEM;
637 		goto failed;
638 	}
639 	dev_set_drvdata(dev, drvdata);
640 
641 	drvdata->base_address = devm_platform_ioremap_resource(pdev, 0);
642 	if (IS_ERR(drvdata->base_address)) {
643 		retval = PTR_ERR(drvdata->base_address);
644 		goto failed;
645 	}
646 
647 	drvdata->devt = devt;
648 	drvdata->dev = dev;
649 	drvdata->config = config;
650 	drvdata->config_regs = config_regs;
651 
652 	mutex_init(&drvdata->sem);
653 	drvdata->is_open = 0;
654 
655 	cdev_init(&drvdata->cdev, &hwicap_fops);
656 	drvdata->cdev.owner = THIS_MODULE;
657 	retval = cdev_add(&drvdata->cdev, devt, 1);
658 	if (retval) {
659 		dev_err(dev, "cdev_add() failed\n");
660 		goto failed;
661 	}
662 
663 	device_create(&icap_class, dev, devt, NULL, "%s%d", DRIVER_NAME, id);
664 	return 0;		/* success */
665 
666  failed:
667 	mutex_lock(&icap_sem);
668 	probed_devices[id] = 0;
669 	mutex_unlock(&icap_sem);
670 
671 	return retval;
672 }
673 
674 static struct hwicap_driver_config buffer_icap_config = {
675 	.get_configuration = buffer_icap_get_configuration,
676 	.set_configuration = buffer_icap_set_configuration,
677 	.get_status = buffer_icap_get_status,
678 	.reset = buffer_icap_reset,
679 };
680 
681 static struct hwicap_driver_config fifo_icap_config = {
682 	.get_configuration = fifo_icap_get_configuration,
683 	.set_configuration = fifo_icap_set_configuration,
684 	.get_status = fifo_icap_get_status,
685 	.reset = fifo_icap_reset,
686 };
687 
688 static int hwicap_drv_probe(struct platform_device *pdev)
689 {
690 	const struct config_registers *regs;
691 	const struct hwicap_driver_config *config;
692 	const char *family;
693 	int id = -1;
694 
695 	config = device_get_match_data(&pdev->dev);
696 
697 	of_property_read_u32(pdev->dev.of_node, "port-number", &id);
698 
699 	/* It's most likely that we're using V4, if the family is not
700 	 * specified
701 	 */
702 	regs = &v4_config_registers;
703 	if (!of_property_read_string(pdev->dev.of_node, "xlnx,family", &family)) {
704 		if (!strcmp(family, "virtex2p"))
705 			regs = &v2_config_registers;
706 		else if (!strcmp(family, "virtex4"))
707 			regs = &v4_config_registers;
708 		else if (!strcmp(family, "virtex5"))
709 			regs = &v5_config_registers;
710 		else if (!strcmp(family, "virtex6"))
711 			regs = &v6_config_registers;
712 	}
713 	return hwicap_setup(pdev, id, config, regs);
714 }
715 
716 static void hwicap_drv_remove(struct platform_device *pdev)
717 {
718 	struct device *dev = &pdev->dev;
719 	struct hwicap_drvdata *drvdata;
720 
721 	drvdata = dev_get_drvdata(dev);
722 
723 	device_destroy(&icap_class, drvdata->devt);
724 	cdev_del(&drvdata->cdev);
725 
726 	mutex_lock(&icap_sem);
727 	probed_devices[MINOR(dev->devt)-XHWICAP_MINOR] = 0;
728 	mutex_unlock(&icap_sem);
729 }
730 
731 /* Match table for device tree binding */
732 static const struct of_device_id hwicap_of_match[] = {
733 	{ .compatible = "xlnx,opb-hwicap-1.00.b", .data = &buffer_icap_config},
734 	{ .compatible = "xlnx,xps-hwicap-1.00.a", .data = &fifo_icap_config},
735 	{},
736 };
737 MODULE_DEVICE_TABLE(of, hwicap_of_match);
738 
739 static struct platform_driver hwicap_platform_driver = {
740 	.probe = hwicap_drv_probe,
741 	.remove = hwicap_drv_remove,
742 	.driver = {
743 		.name = DRIVER_NAME,
744 		.of_match_table = hwicap_of_match,
745 	},
746 };
747 
748 static int __init hwicap_module_init(void)
749 {
750 	dev_t devt;
751 	int retval;
752 
753 	retval = class_register(&icap_class);
754 	if (retval)
755 		return retval;
756 	mutex_init(&icap_sem);
757 
758 	devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR);
759 	retval = register_chrdev_region(devt,
760 					HWICAP_DEVICES,
761 					DRIVER_NAME);
762 	if (retval < 0)
763 		return retval;
764 
765 	retval = platform_driver_register(&hwicap_platform_driver);
766 	if (retval)
767 		goto failed;
768 
769 	return retval;
770 
771  failed:
772 	unregister_chrdev_region(devt, HWICAP_DEVICES);
773 
774 	return retval;
775 }
776 
777 static void __exit hwicap_module_cleanup(void)
778 {
779 	dev_t devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR);
780 
781 	class_unregister(&icap_class);
782 
783 	platform_driver_unregister(&hwicap_platform_driver);
784 
785 	unregister_chrdev_region(devt, HWICAP_DEVICES);
786 }
787 
788 module_init(hwicap_module_init);
789 module_exit(hwicap_module_cleanup);
790 
791 MODULE_AUTHOR("Xilinx, Inc; Xilinx Research Labs Group");
792 MODULE_DESCRIPTION("Xilinx ICAP Port Driver");
793 MODULE_LICENSE("GPL");
794