1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * FPGA Manager Core
   4 *
   5 *  Copyright (C) 2013-2015 Altera Corporation
   6 *  Copyright (C) 2017 Intel Corporation
   7 *
   8 * With code from the mailing list:
   9 * Copyright (C) 2013 Xilinx, Inc.
 
 
 
 
 
 
 
 
 
 
 
 
  10 */
  11#include <linux/firmware.h>
  12#include <linux/fpga/fpga-mgr.h>
  13#include <linux/idr.h>
  14#include <linux/module.h>
  15#include <linux/of.h>
  16#include <linux/mutex.h>
  17#include <linux/slab.h>
  18#include <linux/scatterlist.h>
  19#include <linux/highmem.h>
  20
  21static DEFINE_IDA(fpga_mgr_ida);
  22static const struct class fpga_mgr_class;
  23
  24struct fpga_mgr_devres {
  25	struct fpga_manager *mgr;
  26};
  27
  28static inline void fpga_mgr_fpga_remove(struct fpga_manager *mgr)
  29{
  30	if (mgr->mops->fpga_remove)
  31		mgr->mops->fpga_remove(mgr);
  32}
  33
  34static inline enum fpga_mgr_states fpga_mgr_state(struct fpga_manager *mgr)
  35{
  36	if (mgr->mops->state)
  37		return  mgr->mops->state(mgr);
  38	return FPGA_MGR_STATE_UNKNOWN;
  39}
  40
  41static inline u64 fpga_mgr_status(struct fpga_manager *mgr)
  42{
  43	if (mgr->mops->status)
  44		return mgr->mops->status(mgr);
  45	return 0;
  46}
  47
  48static inline int fpga_mgr_write(struct fpga_manager *mgr, const char *buf, size_t count)
  49{
  50	if (mgr->mops->write)
  51		return  mgr->mops->write(mgr, buf, count);
  52	return -EOPNOTSUPP;
  53}
  54
  55/*
  56 * After all the FPGA image has been written, do the device specific steps to
  57 * finish and set the FPGA into operating mode.
  58 */
  59static inline int fpga_mgr_write_complete(struct fpga_manager *mgr,
  60					  struct fpga_image_info *info)
  61{
  62	int ret = 0;
  63
  64	mgr->state = FPGA_MGR_STATE_WRITE_COMPLETE;
  65	if (mgr->mops->write_complete)
  66		ret = mgr->mops->write_complete(mgr, info);
  67	if (ret) {
  68		dev_err(&mgr->dev, "Error after writing image data to FPGA\n");
  69		mgr->state = FPGA_MGR_STATE_WRITE_COMPLETE_ERR;
  70		return ret;
  71	}
  72	mgr->state = FPGA_MGR_STATE_OPERATING;
  73
  74	return 0;
  75}
  76
  77static inline int fpga_mgr_parse_header(struct fpga_manager *mgr,
  78					struct fpga_image_info *info,
  79					const char *buf, size_t count)
  80{
  81	if (mgr->mops->parse_header)
  82		return mgr->mops->parse_header(mgr, info, buf, count);
  83	return 0;
  84}
  85
  86static inline int fpga_mgr_write_init(struct fpga_manager *mgr,
  87				      struct fpga_image_info *info,
  88				      const char *buf, size_t count)
  89{
  90	if (mgr->mops->write_init)
  91		return  mgr->mops->write_init(mgr, info, buf, count);
  92	return 0;
  93}
  94
  95static inline int fpga_mgr_write_sg(struct fpga_manager *mgr,
  96				    struct sg_table *sgt)
  97{
  98	if (mgr->mops->write_sg)
  99		return  mgr->mops->write_sg(mgr, sgt);
 100	return -EOPNOTSUPP;
 101}
 102
 103/**
 104 * fpga_image_info_alloc - Allocate an FPGA image info struct
 105 * @dev: owning device
 106 *
 107 * Return: struct fpga_image_info or NULL
 108 */
 109struct fpga_image_info *fpga_image_info_alloc(struct device *dev)
 110{
 111	struct fpga_image_info *info;
 112
 113	get_device(dev);
 114
 115	info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
 116	if (!info) {
 117		put_device(dev);
 118		return NULL;
 119	}
 120
 121	info->dev = dev;
 122
 123	return info;
 124}
 125EXPORT_SYMBOL_GPL(fpga_image_info_alloc);
 126
 127/**
 128 * fpga_image_info_free - Free an FPGA image info struct
 129 * @info: FPGA image info struct to free
 130 */
 131void fpga_image_info_free(struct fpga_image_info *info)
 132{
 133	struct device *dev;
 134
 135	if (!info)
 136		return;
 137
 138	dev = info->dev;
 139	if (info->firmware_name)
 140		devm_kfree(dev, info->firmware_name);
 141
 142	devm_kfree(dev, info);
 143	put_device(dev);
 144}
 145EXPORT_SYMBOL_GPL(fpga_image_info_free);
 146
 147/*
 148 * Call the low level driver's parse_header function with entire FPGA image
 149 * buffer on the input. This will set info->header_size and info->data_size.
 150 */
 151static int fpga_mgr_parse_header_mapped(struct fpga_manager *mgr,
 152					struct fpga_image_info *info,
 153					const char *buf, size_t count)
 154{
 155	int ret;
 156
 157	mgr->state = FPGA_MGR_STATE_PARSE_HEADER;
 158	ret = fpga_mgr_parse_header(mgr, info, buf, count);
 159
 160	if (info->header_size + info->data_size > count) {
 161		dev_err(&mgr->dev, "Bitstream data outruns FPGA image\n");
 162		ret = -EINVAL;
 163	}
 164
 165	if (ret) {
 166		dev_err(&mgr->dev, "Error while parsing FPGA image header\n");
 167		mgr->state = FPGA_MGR_STATE_PARSE_HEADER_ERR;
 168	}
 169
 170	return ret;
 171}
 172
 173/*
 174 * Call the low level driver's parse_header function with first fragment of
 175 * scattered FPGA image on the input. If header fits first fragment,
 176 * parse_header will set info->header_size and info->data_size. If it is not,
 177 * parse_header will set desired size to info->header_size and -EAGAIN will be
 178 * returned.
 179 */
 180static int fpga_mgr_parse_header_sg_first(struct fpga_manager *mgr,
 181					  struct fpga_image_info *info,
 182					  struct sg_table *sgt)
 183{
 184	struct sg_mapping_iter miter;
 185	int ret;
 186
 187	mgr->state = FPGA_MGR_STATE_PARSE_HEADER;
 188
 189	sg_miter_start(&miter, sgt->sgl, sgt->nents, SG_MITER_FROM_SG);
 190	if (sg_miter_next(&miter) &&
 191	    miter.length >= info->header_size)
 192		ret = fpga_mgr_parse_header(mgr, info, miter.addr, miter.length);
 193	else
 194		ret = -EAGAIN;
 195	sg_miter_stop(&miter);
 196
 197	if (ret && ret != -EAGAIN) {
 198		dev_err(&mgr->dev, "Error while parsing FPGA image header\n");
 199		mgr->state = FPGA_MGR_STATE_PARSE_HEADER_ERR;
 200	}
 201
 202	return ret;
 203}
 204
 205/*
 206 * Copy scattered FPGA image fragments to temporary buffer and call the
 207 * low level driver's parse_header function. This should be called after
 208 * fpga_mgr_parse_header_sg_first() returned -EAGAIN. In case of success,
 209 * pointer to the newly allocated image header copy will be returned and
 210 * its size will be set into *ret_size. Returned buffer needs to be freed.
 211 */
 212static void *fpga_mgr_parse_header_sg(struct fpga_manager *mgr,
 213				      struct fpga_image_info *info,
 214				      struct sg_table *sgt, size_t *ret_size)
 215{
 216	size_t len, new_header_size, header_size = 0;
 217	char *new_buf, *buf = NULL;
 218	int ret;
 219
 220	do {
 221		new_header_size = info->header_size;
 222		if (new_header_size <= header_size) {
 223			dev_err(&mgr->dev, "Requested invalid header size\n");
 224			ret = -EFAULT;
 225			break;
 226		}
 227
 228		new_buf = krealloc(buf, new_header_size, GFP_KERNEL);
 229		if (!new_buf) {
 230			ret = -ENOMEM;
 231			break;
 232		}
 233
 234		buf = new_buf;
 235
 236		len = sg_pcopy_to_buffer(sgt->sgl, sgt->nents,
 237					 buf + header_size,
 238					 new_header_size - header_size,
 239					 header_size);
 240		if (len != new_header_size - header_size) {
 241			ret = -EFAULT;
 242			break;
 243		}
 244
 245		header_size = new_header_size;
 246		ret = fpga_mgr_parse_header(mgr, info, buf, header_size);
 247	} while (ret == -EAGAIN);
 248
 249	if (ret) {
 250		dev_err(&mgr->dev, "Error while parsing FPGA image header\n");
 251		mgr->state = FPGA_MGR_STATE_PARSE_HEADER_ERR;
 252		kfree(buf);
 253		buf = ERR_PTR(ret);
 254	}
 255
 256	*ret_size = header_size;
 257
 258	return buf;
 259}
 260
 261/*
 262 * Call the low level driver's write_init function. This will do the
 263 * device-specific things to get the FPGA into the state where it is ready to
 264 * receive an FPGA image. The low level driver gets to see at least first
 265 * info->header_size bytes in the buffer. If info->header_size is 0,
 266 * write_init will not get any bytes of image buffer.
 267 */
 268static int fpga_mgr_write_init_buf(struct fpga_manager *mgr,
 269				   struct fpga_image_info *info,
 270				   const char *buf, size_t count)
 271{
 272	size_t header_size = info->header_size;
 273	int ret;
 274
 275	mgr->state = FPGA_MGR_STATE_WRITE_INIT;
 276
 277	if (header_size > count)
 278		ret = -EINVAL;
 279	else if (!header_size)
 280		ret = fpga_mgr_write_init(mgr, info, NULL, 0);
 281	else
 282		ret = fpga_mgr_write_init(mgr, info, buf, count);
 283
 284	if (ret) {
 285		dev_err(&mgr->dev, "Error preparing FPGA for writing\n");
 286		mgr->state = FPGA_MGR_STATE_WRITE_INIT_ERR;
 287		return ret;
 288	}
 289
 290	return 0;
 291}
 292
 293static int fpga_mgr_prepare_sg(struct fpga_manager *mgr,
 294			       struct fpga_image_info *info,
 295			       struct sg_table *sgt)
 296{
 297	struct sg_mapping_iter miter;
 298	size_t len;
 299	char *buf;
 300	int ret;
 301
 302	/* Short path. Low level driver don't care about image header. */
 303	if (!mgr->mops->initial_header_size && !mgr->mops->parse_header)
 304		return fpga_mgr_write_init_buf(mgr, info, NULL, 0);
 305
 306	/*
 307	 * First try to use miter to map the first fragment to access the
 308	 * header, this is the typical path.
 309	 */
 310	ret = fpga_mgr_parse_header_sg_first(mgr, info, sgt);
 311	/* If 0, header fits first fragment, call write_init on it */
 312	if (!ret) {
 313		sg_miter_start(&miter, sgt->sgl, sgt->nents, SG_MITER_FROM_SG);
 314		if (sg_miter_next(&miter)) {
 315			ret = fpga_mgr_write_init_buf(mgr, info, miter.addr,
 316						      miter.length);
 317			sg_miter_stop(&miter);
 318			return ret;
 319		}
 320		sg_miter_stop(&miter);
 321	/*
 322	 * If -EAGAIN, more sg buffer is needed,
 323	 * otherwise an error has occurred.
 324	 */
 325	} else if (ret != -EAGAIN) {
 326		return ret;
 327	}
 328
 329	/*
 330	 * Copy the fragments into temporary memory.
 331	 * Copying is done inside fpga_mgr_parse_header_sg().
 332	 */
 333	buf = fpga_mgr_parse_header_sg(mgr, info, sgt, &len);
 334	if (IS_ERR(buf))
 335		return PTR_ERR(buf);
 336
 337	ret = fpga_mgr_write_init_buf(mgr, info, buf, len);
 338
 339	kfree(buf);
 340
 341	return ret;
 342}
 343
 344/**
 345 * fpga_mgr_buf_load_sg - load fpga from image in buffer from a scatter list
 346 * @mgr:	fpga manager
 347 * @info:	fpga image specific information
 348 * @sgt:	scatterlist table
 
 349 *
 350 * Step the low level fpga manager through the device-specific steps of getting
 351 * an FPGA ready to be configured, writing the image to it, then doing whatever
 352 * post-configuration steps necessary.  This code assumes the caller got the
 353 * mgr pointer from of_fpga_mgr_get() or fpga_mgr_get() and checked that it is
 354 * not an error code.
 355 *
 356 * This is the preferred entry point for FPGA programming, it does not require
 357 * any contiguous kernel memory.
 358 *
 359 * Return: 0 on success, negative error code otherwise.
 360 */
 361static int fpga_mgr_buf_load_sg(struct fpga_manager *mgr,
 362				struct fpga_image_info *info,
 363				struct sg_table *sgt)
 364{
 
 365	int ret;
 366
 367	ret = fpga_mgr_prepare_sg(mgr, info, sgt);
 368	if (ret)
 369		return ret;
 370
 371	/* Write the FPGA image to the FPGA. */
 372	mgr->state = FPGA_MGR_STATE_WRITE;
 373	if (mgr->mops->write_sg) {
 374		ret = fpga_mgr_write_sg(mgr, sgt);
 375	} else {
 376		size_t length, count = 0, data_size = info->data_size;
 377		struct sg_mapping_iter miter;
 378
 379		sg_miter_start(&miter, sgt->sgl, sgt->nents, SG_MITER_FROM_SG);
 380
 381		if (mgr->mops->skip_header &&
 382		    !sg_miter_skip(&miter, info->header_size)) {
 383			ret = -EINVAL;
 384			goto out;
 385		}
 386
 387		while (sg_miter_next(&miter)) {
 388			if (data_size)
 389				length = min(miter.length, data_size - count);
 390			else
 391				length = miter.length;
 392
 393			ret = fpga_mgr_write(mgr, miter.addr, length);
 394			if (ret)
 395				break;
 396
 397			count += length;
 398			if (data_size && count >= data_size)
 399				break;
 400		}
 401		sg_miter_stop(&miter);
 402	}
 403
 404out:
 405	if (ret) {
 406		dev_err(&mgr->dev, "Error while writing image data to FPGA\n");
 407		mgr->state = FPGA_MGR_STATE_WRITE_ERR;
 408		return ret;
 409	}
 410
 411	return fpga_mgr_write_complete(mgr, info);
 412}
 413
 414static int fpga_mgr_buf_load_mapped(struct fpga_manager *mgr,
 415				    struct fpga_image_info *info,
 416				    const char *buf, size_t count)
 417{
 418	int ret;
 419
 420	ret = fpga_mgr_parse_header_mapped(mgr, info, buf, count);
 421	if (ret)
 422		return ret;
 423
 424	ret = fpga_mgr_write_init_buf(mgr, info, buf, count);
 425	if (ret)
 426		return ret;
 427
 428	if (mgr->mops->skip_header) {
 429		buf += info->header_size;
 430		count -= info->header_size;
 431	}
 432
 433	if (info->data_size)
 434		count = info->data_size;
 435
 436	/*
 437	 * Write the FPGA image to the FPGA.
 438	 */
 439	mgr->state = FPGA_MGR_STATE_WRITE;
 440	ret = fpga_mgr_write(mgr, buf, count);
 441	if (ret) {
 442		dev_err(&mgr->dev, "Error while writing image data to FPGA\n");
 443		mgr->state = FPGA_MGR_STATE_WRITE_ERR;
 444		return ret;
 445	}
 446
 447	return fpga_mgr_write_complete(mgr, info);
 448}
 449
 450/**
 451 * fpga_mgr_buf_load - load fpga from image in buffer
 452 * @mgr:	fpga manager
 453 * @info:	fpga image info
 454 * @buf:	buffer contain fpga image
 455 * @count:	byte count of buf
 456 *
 457 * Step the low level fpga manager through the device-specific steps of getting
 458 * an FPGA ready to be configured, writing the image to it, then doing whatever
 459 * post-configuration steps necessary.  This code assumes the caller got the
 460 * mgr pointer from of_fpga_mgr_get() and checked that it is not an error code.
 461 *
 462 * Return: 0 on success, negative error code otherwise.
 463 */
 464static int fpga_mgr_buf_load(struct fpga_manager *mgr,
 465			     struct fpga_image_info *info,
 466			     const char *buf, size_t count)
 467{
 468	struct page **pages;
 469	struct sg_table sgt;
 470	const void *p;
 471	int nr_pages;
 472	int index;
 473	int rc;
 474
 475	/*
 476	 * This is just a fast path if the caller has already created a
 477	 * contiguous kernel buffer and the driver doesn't require SG, non-SG
 478	 * drivers will still work on the slow path.
 479	 */
 480	if (mgr->mops->write)
 481		return fpga_mgr_buf_load_mapped(mgr, info, buf, count);
 482
 483	/*
 484	 * Convert the linear kernel pointer into a sg_table of pages for use
 485	 * by the driver.
 486	 */
 487	nr_pages = DIV_ROUND_UP((unsigned long)buf + count, PAGE_SIZE) -
 488		   (unsigned long)buf / PAGE_SIZE;
 489	pages = kmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL);
 490	if (!pages)
 491		return -ENOMEM;
 492
 493	p = buf - offset_in_page(buf);
 494	for (index = 0; index < nr_pages; index++) {
 495		if (is_vmalloc_addr(p))
 496			pages[index] = vmalloc_to_page(p);
 497		else
 498			pages[index] = kmap_to_page((void *)p);
 499		if (!pages[index]) {
 500			kfree(pages);
 501			return -EFAULT;
 502		}
 503		p += PAGE_SIZE;
 504	}
 
 505
 506	/*
 507	 * The temporary pages list is used to code share the merging algorithm
 508	 * in sg_alloc_table_from_pages
 509	 */
 510	rc = sg_alloc_table_from_pages(&sgt, pages, index, offset_in_page(buf),
 511				       count, GFP_KERNEL);
 512	kfree(pages);
 513	if (rc)
 514		return rc;
 515
 516	rc = fpga_mgr_buf_load_sg(mgr, info, &sgt);
 517	sg_free_table(&sgt);
 518
 519	return rc;
 520}
 
 521
 522/**
 523 * fpga_mgr_firmware_load - request firmware and load to fpga
 524 * @mgr:	fpga manager
 525 * @info:	fpga image specific information
 526 * @image_name:	name of image file on the firmware search path
 527 *
 528 * Request an FPGA image using the firmware class, then write out to the FPGA.
 529 * Update the state before each step to provide info on what step failed if
 530 * there is a failure.  This code assumes the caller got the mgr pointer
 531 * from of_fpga_mgr_get() or fpga_mgr_get() and checked that it is not an error
 532 * code.
 533 *
 534 * Return: 0 on success, negative error code otherwise.
 535 */
 536static int fpga_mgr_firmware_load(struct fpga_manager *mgr,
 537				  struct fpga_image_info *info,
 538				  const char *image_name)
 539{
 540	struct device *dev = &mgr->dev;
 541	const struct firmware *fw;
 542	int ret;
 543
 544	dev_info(dev, "writing %s to %s\n", image_name, mgr->name);
 545
 546	mgr->state = FPGA_MGR_STATE_FIRMWARE_REQ;
 547
 548	ret = request_firmware(&fw, image_name, dev);
 549	if (ret) {
 550		mgr->state = FPGA_MGR_STATE_FIRMWARE_REQ_ERR;
 551		dev_err(dev, "Error requesting firmware %s\n", image_name);
 552		return ret;
 553	}
 554
 555	ret = fpga_mgr_buf_load(mgr, info, fw->data, fw->size);
 556
 557	release_firmware(fw);
 558
 559	return ret;
 560}
 561
 562/**
 563 * fpga_mgr_load - load FPGA from scatter/gather table, buffer, or firmware
 564 * @mgr:	fpga manager
 565 * @info:	fpga image information.
 566 *
 567 * Load the FPGA from an image which is indicated in @info.  If successful, the
 568 * FPGA ends up in operating mode.
 569 *
 570 * Return: 0 on success, negative error code otherwise.
 571 */
 572int fpga_mgr_load(struct fpga_manager *mgr, struct fpga_image_info *info)
 573{
 574	info->header_size = mgr->mops->initial_header_size;
 575
 576	if (info->sgt)
 577		return fpga_mgr_buf_load_sg(mgr, info, info->sgt);
 578	if (info->buf && info->count)
 579		return fpga_mgr_buf_load(mgr, info, info->buf, info->count);
 580	if (info->firmware_name)
 581		return fpga_mgr_firmware_load(mgr, info, info->firmware_name);
 582	return -EINVAL;
 583}
 584EXPORT_SYMBOL_GPL(fpga_mgr_load);
 585
 586static const char * const state_str[] = {
 587	[FPGA_MGR_STATE_UNKNOWN] =		"unknown",
 588	[FPGA_MGR_STATE_POWER_OFF] =		"power off",
 589	[FPGA_MGR_STATE_POWER_UP] =		"power up",
 590	[FPGA_MGR_STATE_RESET] =		"reset",
 591
 592	/* requesting FPGA image from firmware */
 593	[FPGA_MGR_STATE_FIRMWARE_REQ] =		"firmware request",
 594	[FPGA_MGR_STATE_FIRMWARE_REQ_ERR] =	"firmware request error",
 595
 596	/* Parse FPGA image header */
 597	[FPGA_MGR_STATE_PARSE_HEADER] =		"parse header",
 598	[FPGA_MGR_STATE_PARSE_HEADER_ERR] =	"parse header error",
 599
 600	/* Preparing FPGA to receive image */
 601	[FPGA_MGR_STATE_WRITE_INIT] =		"write init",
 602	[FPGA_MGR_STATE_WRITE_INIT_ERR] =	"write init error",
 603
 604	/* Writing image to FPGA */
 605	[FPGA_MGR_STATE_WRITE] =		"write",
 606	[FPGA_MGR_STATE_WRITE_ERR] =		"write error",
 607
 608	/* Finishing configuration after image has been written */
 609	[FPGA_MGR_STATE_WRITE_COMPLETE] =	"write complete",
 610	[FPGA_MGR_STATE_WRITE_COMPLETE_ERR] =	"write complete error",
 611
 612	/* FPGA reports to be in normal operating mode */
 613	[FPGA_MGR_STATE_OPERATING] =		"operating",
 614};
 615
 616static ssize_t name_show(struct device *dev,
 617			 struct device_attribute *attr, char *buf)
 618{
 619	struct fpga_manager *mgr = to_fpga_manager(dev);
 620
 621	return sprintf(buf, "%s\n", mgr->name);
 622}
 623
 624static ssize_t state_show(struct device *dev,
 625			  struct device_attribute *attr, char *buf)
 626{
 627	struct fpga_manager *mgr = to_fpga_manager(dev);
 628
 629	return sprintf(buf, "%s\n", state_str[mgr->state]);
 630}
 631
 632static ssize_t status_show(struct device *dev,
 633			   struct device_attribute *attr, char *buf)
 634{
 635	struct fpga_manager *mgr = to_fpga_manager(dev);
 636	u64 status;
 637	int len = 0;
 638
 639	status = fpga_mgr_status(mgr);
 640
 641	if (status & FPGA_MGR_STATUS_OPERATION_ERR)
 642		len += sprintf(buf + len, "reconfig operation error\n");
 643	if (status & FPGA_MGR_STATUS_CRC_ERR)
 644		len += sprintf(buf + len, "reconfig CRC error\n");
 645	if (status & FPGA_MGR_STATUS_INCOMPATIBLE_IMAGE_ERR)
 646		len += sprintf(buf + len, "reconfig incompatible image\n");
 647	if (status & FPGA_MGR_STATUS_IP_PROTOCOL_ERR)
 648		len += sprintf(buf + len, "reconfig IP protocol error\n");
 649	if (status & FPGA_MGR_STATUS_FIFO_OVERFLOW_ERR)
 650		len += sprintf(buf + len, "reconfig fifo overflow error\n");
 651
 652	return len;
 653}
 654
 655static DEVICE_ATTR_RO(name);
 656static DEVICE_ATTR_RO(state);
 657static DEVICE_ATTR_RO(status);
 658
 659static struct attribute *fpga_mgr_attrs[] = {
 660	&dev_attr_name.attr,
 661	&dev_attr_state.attr,
 662	&dev_attr_status.attr,
 663	NULL,
 664};
 665ATTRIBUTE_GROUPS(fpga_mgr);
 666
 667static struct fpga_manager *__fpga_mgr_get(struct device *mgr_dev)
 668{
 669	struct fpga_manager *mgr;
 
 
 
 
 
 670
 671	mgr = to_fpga_manager(mgr_dev);
 
 
 
 
 672
 673	if (!try_module_get(mgr->mops_owner))
 674		mgr = ERR_PTR(-ENODEV);
 675
 676	return mgr;
 
 
 
 
 
 
 677}
 678
 679static int fpga_mgr_dev_match(struct device *dev, const void *data)
 680{
 681	return dev->parent == data;
 682}
 683
 684/**
 685 * fpga_mgr_get - Given a device, get a reference to an fpga mgr.
 686 * @dev:	parent device that fpga mgr was registered with
 687 *
 
 
 688 * Return: fpga manager struct or IS_ERR() condition containing error code.
 689 */
 690struct fpga_manager *fpga_mgr_get(struct device *dev)
 691{
 692	struct fpga_manager *mgr;
 693	struct device *mgr_dev;
 694
 695	mgr_dev = class_find_device(&fpga_mgr_class, NULL, dev, fpga_mgr_dev_match);
 696	if (!mgr_dev)
 697		return ERR_PTR(-ENODEV);
 698
 699	mgr = __fpga_mgr_get(mgr_dev);
 700	if (IS_ERR(mgr))
 701		put_device(mgr_dev);
 702
 703	return mgr;
 704}
 705EXPORT_SYMBOL_GPL(fpga_mgr_get);
 706
 
 
 
 
 
 707/**
 708 * of_fpga_mgr_get - Given a device node, get a reference to an fpga mgr.
 709 *
 710 * @node:	device node
 711 *
 
 
 712 * Return: fpga manager struct or IS_ERR() condition containing error code.
 713 */
 714struct fpga_manager *of_fpga_mgr_get(struct device_node *node)
 715{
 716	struct fpga_manager *mgr;
 717	struct device *mgr_dev;
 718
 719	mgr_dev = class_find_device_by_of_node(&fpga_mgr_class, node);
 720	if (!mgr_dev)
 
 721		return ERR_PTR(-ENODEV);
 722
 723	mgr = __fpga_mgr_get(mgr_dev);
 724	if (IS_ERR(mgr))
 725		put_device(mgr_dev);
 726
 727	return mgr;
 728}
 729EXPORT_SYMBOL_GPL(of_fpga_mgr_get);
 730
 731/**
 732 * fpga_mgr_put - release a reference to an fpga manager
 733 * @mgr:	fpga manager structure
 734 */
 735void fpga_mgr_put(struct fpga_manager *mgr)
 736{
 737	module_put(mgr->mops_owner);
 
 738	put_device(&mgr->dev);
 739}
 740EXPORT_SYMBOL_GPL(fpga_mgr_put);
 741
 742/**
 743 * fpga_mgr_lock - Lock FPGA manager for exclusive use
 744 * @mgr:	fpga manager
 745 *
 746 * Given a pointer to FPGA Manager (from fpga_mgr_get() or
 747 * of_fpga_mgr_put()) attempt to get the mutex. The user should call
 748 * fpga_mgr_lock() and verify that it returns 0 before attempting to
 749 * program the FPGA.  Likewise, the user should call fpga_mgr_unlock
 750 * when done programming the FPGA.
 751 *
 752 * Return: 0 for success or -EBUSY
 753 */
 754int fpga_mgr_lock(struct fpga_manager *mgr)
 755{
 756	if (!mutex_trylock(&mgr->ref_mutex)) {
 757		dev_err(&mgr->dev, "FPGA manager is in use.\n");
 758		return -EBUSY;
 759	}
 760
 761	return 0;
 762}
 763EXPORT_SYMBOL_GPL(fpga_mgr_lock);
 764
 765/**
 766 * fpga_mgr_unlock - Unlock FPGA manager after done programming
 767 * @mgr:	fpga manager
 768 */
 769void fpga_mgr_unlock(struct fpga_manager *mgr)
 770{
 771	mutex_unlock(&mgr->ref_mutex);
 772}
 773EXPORT_SYMBOL_GPL(fpga_mgr_unlock);
 774
 775/**
 776 * __fpga_mgr_register_full - create and register an FPGA Manager device
 777 * @parent:	fpga manager device from pdev
 778 * @info:	parameters for fpga manager
 779 * @owner:	owner module containing the ops
 780 *
 781 * The caller of this function is responsible for calling fpga_mgr_unregister().
 782 * Using devm_fpga_mgr_register_full() instead is recommended.
 783 *
 784 * Return: pointer to struct fpga_manager pointer or ERR_PTR()
 785 */
 786struct fpga_manager *
 787__fpga_mgr_register_full(struct device *parent, const struct fpga_manager_info *info,
 788			 struct module *owner)
 789{
 790	const struct fpga_manager_ops *mops = info->mops;
 791	struct fpga_manager *mgr;
 792	int id, ret;
 793
 794	if (!mops) {
 795		dev_err(parent, "Attempt to register without fpga_manager_ops\n");
 796		return ERR_PTR(-EINVAL);
 
 797	}
 798
 799	if (!info->name || !strlen(info->name)) {
 800		dev_err(parent, "Attempt to register with no name!\n");
 801		return ERR_PTR(-EINVAL);
 802	}
 803
 804	mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
 805	if (!mgr)
 806		return ERR_PTR(-ENOMEM);
 807
 808	id = ida_alloc(&fpga_mgr_ida, GFP_KERNEL);
 809	if (id < 0) {
 810		ret = id;
 811		goto error_kfree;
 812	}
 813
 814	mutex_init(&mgr->ref_mutex);
 815
 816	mgr->mops_owner = owner;
 
 
 
 
 
 
 
 
 
 817
 818	mgr->name = info->name;
 819	mgr->mops = info->mops;
 820	mgr->priv = info->priv;
 821	mgr->compat_id = info->compat_id;
 822
 823	mgr->dev.class = &fpga_mgr_class;
 824	mgr->dev.groups = mops->groups;
 825	mgr->dev.parent = parent;
 826	mgr->dev.of_node = parent->of_node;
 827	mgr->dev.id = id;
 
 828
 829	ret = dev_set_name(&mgr->dev, "fpga%d", id);
 830	if (ret)
 831		goto error_device;
 832
 833	/*
 834	 * Initialize framework state by requesting low level driver read state
 835	 * from device.  FPGA may be in reset mode or may have been programmed
 836	 * by bootloader or EEPROM.
 837	 */
 838	mgr->state = fpga_mgr_state(mgr);
 839
 840	ret = device_register(&mgr->dev);
 841	if (ret) {
 842		put_device(&mgr->dev);
 843		return ERR_PTR(ret);
 844	}
 845
 846	return mgr;
 847
 848error_device:
 849	ida_free(&fpga_mgr_ida, id);
 850error_kfree:
 851	kfree(mgr);
 852
 853	return ERR_PTR(ret);
 854}
 855EXPORT_SYMBOL_GPL(__fpga_mgr_register_full);
 856
 857/**
 858 * __fpga_mgr_register - create and register an FPGA Manager device
 859 * @parent:	fpga manager device from pdev
 860 * @name:	fpga manager name
 861 * @mops:	pointer to structure of fpga manager ops
 862 * @priv:	fpga manager private data
 863 * @owner:	owner module containing the ops
 864 *
 865 * The caller of this function is responsible for calling fpga_mgr_unregister().
 866 * Using devm_fpga_mgr_register() instead is recommended. This simple
 867 * version of the register function should be sufficient for most users. The
 868 * fpga_mgr_register_full() function is available for users that need to pass
 869 * additional, optional parameters.
 870 *
 871 * Return: pointer to struct fpga_manager pointer or ERR_PTR()
 872 */
 873struct fpga_manager *
 874__fpga_mgr_register(struct device *parent, const char *name,
 875		    const struct fpga_manager_ops *mops, void *priv, struct module *owner)
 876{
 877	struct fpga_manager_info info = { 0 };
 878
 879	info.name = name;
 880	info.mops = mops;
 881	info.priv = priv;
 882
 883	return __fpga_mgr_register_full(parent, &info, owner);
 884}
 885EXPORT_SYMBOL_GPL(__fpga_mgr_register);
 886
 887/**
 888 * fpga_mgr_unregister - unregister an FPGA manager
 889 * @mgr: fpga manager struct
 890 *
 891 * This function is intended for use in an FPGA manager driver's remove function.
 892 */
 893void fpga_mgr_unregister(struct fpga_manager *mgr)
 894{
 895	dev_info(&mgr->dev, "%s %s\n", __func__, mgr->name);
 896
 897	/*
 898	 * If the low level driver provides a method for putting fpga into
 899	 * a desired state upon unregister, do it.
 900	 */
 901	fpga_mgr_fpga_remove(mgr);
 
 902
 903	device_unregister(&mgr->dev);
 904}
 905EXPORT_SYMBOL_GPL(fpga_mgr_unregister);
 906
 907static void devm_fpga_mgr_unregister(struct device *dev, void *res)
 908{
 909	struct fpga_mgr_devres *dr = res;
 910
 911	fpga_mgr_unregister(dr->mgr);
 912}
 913
 914/**
 915 * __devm_fpga_mgr_register_full - resource managed variant of fpga_mgr_register()
 916 * @parent:	fpga manager device from pdev
 917 * @info:	parameters for fpga manager
 918 * @owner:	owner module containing the ops
 919 *
 920 * Return:  fpga manager pointer on success, negative error code otherwise.
 921 *
 922 * This is the devres variant of fpga_mgr_register_full() for which the unregister
 923 * function will be called automatically when the managing device is detached.
 924 */
 925struct fpga_manager *
 926__devm_fpga_mgr_register_full(struct device *parent, const struct fpga_manager_info *info,
 927			      struct module *owner)
 928{
 929	struct fpga_mgr_devres *dr;
 930	struct fpga_manager *mgr;
 931
 932	dr = devres_alloc(devm_fpga_mgr_unregister, sizeof(*dr), GFP_KERNEL);
 933	if (!dr)
 934		return ERR_PTR(-ENOMEM);
 935
 936	mgr = __fpga_mgr_register_full(parent, info, owner);
 937	if (IS_ERR(mgr)) {
 938		devres_free(dr);
 939		return mgr;
 940	}
 941
 942	dr->mgr = mgr;
 943	devres_add(parent, dr);
 944
 945	return mgr;
 946}
 947EXPORT_SYMBOL_GPL(__devm_fpga_mgr_register_full);
 948
 949/**
 950 * __devm_fpga_mgr_register - resource managed variant of fpga_mgr_register()
 951 * @parent:	fpga manager device from pdev
 952 * @name:	fpga manager name
 953 * @mops:	pointer to structure of fpga manager ops
 954 * @priv:	fpga manager private data
 955 * @owner:	owner module containing the ops
 956 *
 957 * Return:  fpga manager pointer on success, negative error code otherwise.
 958 *
 959 * This is the devres variant of fpga_mgr_register() for which the
 960 * unregister function will be called automatically when the managing
 961 * device is detached.
 962 */
 963struct fpga_manager *
 964__devm_fpga_mgr_register(struct device *parent, const char *name,
 965			 const struct fpga_manager_ops *mops, void *priv,
 966			 struct module *owner)
 967{
 968	struct fpga_manager_info info = { 0 };
 969
 970	info.name = name;
 971	info.mops = mops;
 972	info.priv = priv;
 973
 974	return __devm_fpga_mgr_register_full(parent, &info, owner);
 975}
 976EXPORT_SYMBOL_GPL(__devm_fpga_mgr_register);
 977
 978static void fpga_mgr_dev_release(struct device *dev)
 979{
 980	struct fpga_manager *mgr = to_fpga_manager(dev);
 981
 982	ida_free(&fpga_mgr_ida, mgr->dev.id);
 983	kfree(mgr);
 984}
 985
 986static const struct class fpga_mgr_class = {
 987	.name = "fpga_manager",
 988	.dev_groups = fpga_mgr_groups,
 989	.dev_release = fpga_mgr_dev_release,
 990};
 991
 992static int __init fpga_mgr_class_init(void)
 993{
 994	pr_info("FPGA manager framework\n");
 995
 996	return class_register(&fpga_mgr_class);
 
 
 
 
 
 
 
 997}
 998
 999static void __exit fpga_mgr_class_exit(void)
1000{
1001	class_unregister(&fpga_mgr_class);
1002	ida_destroy(&fpga_mgr_ida);
1003}
1004
1005MODULE_AUTHOR("Alan Tull <atull@kernel.org>");
1006MODULE_DESCRIPTION("FPGA manager framework");
1007MODULE_LICENSE("GPL v2");
1008
1009subsys_initcall(fpga_mgr_class_init);
1010module_exit(fpga_mgr_class_exit);