xref: /linux/drivers/crypto/omap-sham.c (revision b889fcf63cb62e7fdb7816565e28f44dbe4a76a5)
1 /*
2  * Cryptographic API.
3  *
4  * Support for OMAP SHA1/MD5 HW acceleration.
5  *
6  * Copyright (c) 2010 Nokia Corporation
7  * Author: Dmitry Kasatkin <dmitry.kasatkin@nokia.com>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as published
11  * by the Free Software Foundation.
12  *
13  * Some ideas are from old omap-sha1-md5.c driver.
14  */
15 
16 #define pr_fmt(fmt) "%s: " fmt, __func__
17 
18 #include <linux/err.h>
19 #include <linux/device.h>
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/errno.h>
23 #include <linux/interrupt.h>
24 #include <linux/kernel.h>
25 #include <linux/clk.h>
26 #include <linux/irq.h>
27 #include <linux/io.h>
28 #include <linux/platform_device.h>
29 #include <linux/scatterlist.h>
30 #include <linux/dma-mapping.h>
31 #include <linux/delay.h>
32 #include <linux/crypto.h>
33 #include <linux/cryptohash.h>
34 #include <crypto/scatterwalk.h>
35 #include <crypto/algapi.h>
36 #include <crypto/sha.h>
37 #include <crypto/hash.h>
38 #include <crypto/internal/hash.h>
39 
40 #include <linux/omap-dma.h>
41 #include <mach/irqs.h>
42 
43 #define SHA_REG_DIGEST(x)		(0x00 + ((x) * 0x04))
44 #define SHA_REG_DIN(x)			(0x1C + ((x) * 0x04))
45 
46 #define SHA1_MD5_BLOCK_SIZE		SHA1_BLOCK_SIZE
47 #define MD5_DIGEST_SIZE			16
48 
49 #define SHA_REG_DIGCNT			0x14
50 
51 #define SHA_REG_CTRL			0x18
52 #define SHA_REG_CTRL_LENGTH		(0xFFFFFFFF << 5)
53 #define SHA_REG_CTRL_CLOSE_HASH		(1 << 4)
54 #define SHA_REG_CTRL_ALGO_CONST		(1 << 3)
55 #define SHA_REG_CTRL_ALGO		(1 << 2)
56 #define SHA_REG_CTRL_INPUT_READY	(1 << 1)
57 #define SHA_REG_CTRL_OUTPUT_READY	(1 << 0)
58 
59 #define SHA_REG_REV			0x5C
60 #define SHA_REG_REV_MAJOR		0xF0
61 #define SHA_REG_REV_MINOR		0x0F
62 
63 #define SHA_REG_MASK			0x60
64 #define SHA_REG_MASK_DMA_EN		(1 << 3)
65 #define SHA_REG_MASK_IT_EN		(1 << 2)
66 #define SHA_REG_MASK_SOFTRESET		(1 << 1)
67 #define SHA_REG_AUTOIDLE		(1 << 0)
68 
69 #define SHA_REG_SYSSTATUS		0x64
70 #define SHA_REG_SYSSTATUS_RESETDONE	(1 << 0)
71 
72 #define DEFAULT_TIMEOUT_INTERVAL	HZ
73 
74 /* mostly device flags */
75 #define FLAGS_BUSY		0
76 #define FLAGS_FINAL		1
77 #define FLAGS_DMA_ACTIVE	2
78 #define FLAGS_OUTPUT_READY	3
79 #define FLAGS_INIT		4
80 #define FLAGS_CPU		5
81 #define FLAGS_DMA_READY		6
82 /* context flags */
83 #define FLAGS_FINUP		16
84 #define FLAGS_SG		17
85 #define FLAGS_SHA1		18
86 #define FLAGS_HMAC		19
87 #define FLAGS_ERROR		20
88 
89 #define OP_UPDATE	1
90 #define OP_FINAL	2
91 
92 #define OMAP_ALIGN_MASK		(sizeof(u32)-1)
93 #define OMAP_ALIGNED		__attribute__((aligned(sizeof(u32))))
94 
95 #define BUFLEN		PAGE_SIZE
96 
97 struct omap_sham_dev;
98 
99 struct omap_sham_reqctx {
100 	struct omap_sham_dev	*dd;
101 	unsigned long		flags;
102 	unsigned long		op;
103 
104 	u8			digest[SHA1_DIGEST_SIZE] OMAP_ALIGNED;
105 	size_t			digcnt;
106 	size_t			bufcnt;
107 	size_t			buflen;
108 	dma_addr_t		dma_addr;
109 
110 	/* walk state */
111 	struct scatterlist	*sg;
112 	unsigned int		offset;	/* offset in current sg */
113 	unsigned int		total;	/* total request */
114 
115 	u8			buffer[0] OMAP_ALIGNED;
116 };
117 
118 struct omap_sham_hmac_ctx {
119 	struct crypto_shash	*shash;
120 	u8			ipad[SHA1_MD5_BLOCK_SIZE];
121 	u8			opad[SHA1_MD5_BLOCK_SIZE];
122 };
123 
124 struct omap_sham_ctx {
125 	struct omap_sham_dev	*dd;
126 
127 	unsigned long		flags;
128 
129 	/* fallback stuff */
130 	struct crypto_shash	*fallback;
131 
132 	struct omap_sham_hmac_ctx base[0];
133 };
134 
135 #define OMAP_SHAM_QUEUE_LENGTH	1
136 
137 struct omap_sham_dev {
138 	struct list_head	list;
139 	unsigned long		phys_base;
140 	struct device		*dev;
141 	void __iomem		*io_base;
142 	int			irq;
143 	struct clk		*iclk;
144 	spinlock_t		lock;
145 	int			err;
146 	int			dma;
147 	int			dma_lch;
148 	struct tasklet_struct	done_task;
149 
150 	unsigned long		flags;
151 	struct crypto_queue	queue;
152 	struct ahash_request	*req;
153 };
154 
155 struct omap_sham_drv {
156 	struct list_head	dev_list;
157 	spinlock_t		lock;
158 	unsigned long		flags;
159 };
160 
161 static struct omap_sham_drv sham = {
162 	.dev_list = LIST_HEAD_INIT(sham.dev_list),
163 	.lock = __SPIN_LOCK_UNLOCKED(sham.lock),
164 };
165 
166 static inline u32 omap_sham_read(struct omap_sham_dev *dd, u32 offset)
167 {
168 	return __raw_readl(dd->io_base + offset);
169 }
170 
171 static inline void omap_sham_write(struct omap_sham_dev *dd,
172 					u32 offset, u32 value)
173 {
174 	__raw_writel(value, dd->io_base + offset);
175 }
176 
177 static inline void omap_sham_write_mask(struct omap_sham_dev *dd, u32 address,
178 					u32 value, u32 mask)
179 {
180 	u32 val;
181 
182 	val = omap_sham_read(dd, address);
183 	val &= ~mask;
184 	val |= value;
185 	omap_sham_write(dd, address, val);
186 }
187 
188 static inline int omap_sham_wait(struct omap_sham_dev *dd, u32 offset, u32 bit)
189 {
190 	unsigned long timeout = jiffies + DEFAULT_TIMEOUT_INTERVAL;
191 
192 	while (!(omap_sham_read(dd, offset) & bit)) {
193 		if (time_is_before_jiffies(timeout))
194 			return -ETIMEDOUT;
195 	}
196 
197 	return 0;
198 }
199 
200 static void omap_sham_copy_hash(struct ahash_request *req, int out)
201 {
202 	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
203 	u32 *hash = (u32 *)ctx->digest;
204 	int i;
205 
206 	/* MD5 is almost unused. So copy sha1 size to reduce code */
207 	for (i = 0; i < SHA1_DIGEST_SIZE / sizeof(u32); i++) {
208 		if (out)
209 			hash[i] = omap_sham_read(ctx->dd,
210 						SHA_REG_DIGEST(i));
211 		else
212 			omap_sham_write(ctx->dd,
213 					SHA_REG_DIGEST(i), hash[i]);
214 	}
215 }
216 
217 static void omap_sham_copy_ready_hash(struct ahash_request *req)
218 {
219 	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
220 	u32 *in = (u32 *)ctx->digest;
221 	u32 *hash = (u32 *)req->result;
222 	int i;
223 
224 	if (!hash)
225 		return;
226 
227 	if (likely(ctx->flags & BIT(FLAGS_SHA1))) {
228 		/* SHA1 results are in big endian */
229 		for (i = 0; i < SHA1_DIGEST_SIZE / sizeof(u32); i++)
230 			hash[i] = be32_to_cpu(in[i]);
231 	} else {
232 		/* MD5 results are in little endian */
233 		for (i = 0; i < MD5_DIGEST_SIZE / sizeof(u32); i++)
234 			hash[i] = le32_to_cpu(in[i]);
235 	}
236 }
237 
238 static int omap_sham_hw_init(struct omap_sham_dev *dd)
239 {
240 	clk_enable(dd->iclk);
241 
242 	if (!test_bit(FLAGS_INIT, &dd->flags)) {
243 		omap_sham_write_mask(dd, SHA_REG_MASK,
244 			SHA_REG_MASK_SOFTRESET, SHA_REG_MASK_SOFTRESET);
245 
246 		if (omap_sham_wait(dd, SHA_REG_SYSSTATUS,
247 					SHA_REG_SYSSTATUS_RESETDONE))
248 			return -ETIMEDOUT;
249 
250 		set_bit(FLAGS_INIT, &dd->flags);
251 		dd->err = 0;
252 	}
253 
254 	return 0;
255 }
256 
257 static void omap_sham_write_ctrl(struct omap_sham_dev *dd, size_t length,
258 				 int final, int dma)
259 {
260 	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
261 	u32 val = length << 5, mask;
262 
263 	if (likely(ctx->digcnt))
264 		omap_sham_write(dd, SHA_REG_DIGCNT, ctx->digcnt);
265 
266 	omap_sham_write_mask(dd, SHA_REG_MASK,
267 		SHA_REG_MASK_IT_EN | (dma ? SHA_REG_MASK_DMA_EN : 0),
268 		SHA_REG_MASK_IT_EN | SHA_REG_MASK_DMA_EN);
269 	/*
270 	 * Setting ALGO_CONST only for the first iteration
271 	 * and CLOSE_HASH only for the last one.
272 	 */
273 	if (ctx->flags & BIT(FLAGS_SHA1))
274 		val |= SHA_REG_CTRL_ALGO;
275 	if (!ctx->digcnt)
276 		val |= SHA_REG_CTRL_ALGO_CONST;
277 	if (final)
278 		val |= SHA_REG_CTRL_CLOSE_HASH;
279 
280 	mask = SHA_REG_CTRL_ALGO_CONST | SHA_REG_CTRL_CLOSE_HASH |
281 			SHA_REG_CTRL_ALGO | SHA_REG_CTRL_LENGTH;
282 
283 	omap_sham_write_mask(dd, SHA_REG_CTRL, val, mask);
284 }
285 
286 static int omap_sham_xmit_cpu(struct omap_sham_dev *dd, const u8 *buf,
287 			      size_t length, int final)
288 {
289 	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
290 	int count, len32;
291 	const u32 *buffer = (const u32 *)buf;
292 
293 	dev_dbg(dd->dev, "xmit_cpu: digcnt: %d, length: %d, final: %d\n",
294 						ctx->digcnt, length, final);
295 
296 	omap_sham_write_ctrl(dd, length, final, 0);
297 
298 	/* should be non-zero before next lines to disable clocks later */
299 	ctx->digcnt += length;
300 
301 	if (omap_sham_wait(dd, SHA_REG_CTRL, SHA_REG_CTRL_INPUT_READY))
302 		return -ETIMEDOUT;
303 
304 	if (final)
305 		set_bit(FLAGS_FINAL, &dd->flags); /* catch last interrupt */
306 
307 	set_bit(FLAGS_CPU, &dd->flags);
308 
309 	len32 = DIV_ROUND_UP(length, sizeof(u32));
310 
311 	for (count = 0; count < len32; count++)
312 		omap_sham_write(dd, SHA_REG_DIN(count), buffer[count]);
313 
314 	return -EINPROGRESS;
315 }
316 
317 static int omap_sham_xmit_dma(struct omap_sham_dev *dd, dma_addr_t dma_addr,
318 			      size_t length, int final)
319 {
320 	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
321 	int len32;
322 
323 	dev_dbg(dd->dev, "xmit_dma: digcnt: %d, length: %d, final: %d\n",
324 						ctx->digcnt, length, final);
325 
326 	len32 = DIV_ROUND_UP(length, sizeof(u32));
327 
328 	omap_set_dma_transfer_params(dd->dma_lch, OMAP_DMA_DATA_TYPE_S32, len32,
329 			1, OMAP_DMA_SYNC_PACKET, dd->dma,
330 				OMAP_DMA_DST_SYNC_PREFETCH);
331 
332 	omap_set_dma_src_params(dd->dma_lch, 0, OMAP_DMA_AMODE_POST_INC,
333 				dma_addr, 0, 0);
334 
335 	omap_sham_write_ctrl(dd, length, final, 1);
336 
337 	ctx->digcnt += length;
338 
339 	if (final)
340 		set_bit(FLAGS_FINAL, &dd->flags); /* catch last interrupt */
341 
342 	set_bit(FLAGS_DMA_ACTIVE, &dd->flags);
343 
344 	omap_start_dma(dd->dma_lch);
345 
346 	return -EINPROGRESS;
347 }
348 
349 static size_t omap_sham_append_buffer(struct omap_sham_reqctx *ctx,
350 				const u8 *data, size_t length)
351 {
352 	size_t count = min(length, ctx->buflen - ctx->bufcnt);
353 
354 	count = min(count, ctx->total);
355 	if (count <= 0)
356 		return 0;
357 	memcpy(ctx->buffer + ctx->bufcnt, data, count);
358 	ctx->bufcnt += count;
359 
360 	return count;
361 }
362 
363 static size_t omap_sham_append_sg(struct omap_sham_reqctx *ctx)
364 {
365 	size_t count;
366 
367 	while (ctx->sg) {
368 		count = omap_sham_append_buffer(ctx,
369 				sg_virt(ctx->sg) + ctx->offset,
370 				ctx->sg->length - ctx->offset);
371 		if (!count)
372 			break;
373 		ctx->offset += count;
374 		ctx->total -= count;
375 		if (ctx->offset == ctx->sg->length) {
376 			ctx->sg = sg_next(ctx->sg);
377 			if (ctx->sg)
378 				ctx->offset = 0;
379 			else
380 				ctx->total = 0;
381 		}
382 	}
383 
384 	return 0;
385 }
386 
387 static int omap_sham_xmit_dma_map(struct omap_sham_dev *dd,
388 					struct omap_sham_reqctx *ctx,
389 					size_t length, int final)
390 {
391 	ctx->dma_addr = dma_map_single(dd->dev, ctx->buffer, ctx->buflen,
392 				       DMA_TO_DEVICE);
393 	if (dma_mapping_error(dd->dev, ctx->dma_addr)) {
394 		dev_err(dd->dev, "dma %u bytes error\n", ctx->buflen);
395 		return -EINVAL;
396 	}
397 
398 	ctx->flags &= ~BIT(FLAGS_SG);
399 
400 	/* next call does not fail... so no unmap in the case of error */
401 	return omap_sham_xmit_dma(dd, ctx->dma_addr, length, final);
402 }
403 
404 static int omap_sham_update_dma_slow(struct omap_sham_dev *dd)
405 {
406 	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
407 	unsigned int final;
408 	size_t count;
409 
410 	omap_sham_append_sg(ctx);
411 
412 	final = (ctx->flags & BIT(FLAGS_FINUP)) && !ctx->total;
413 
414 	dev_dbg(dd->dev, "slow: bufcnt: %u, digcnt: %d, final: %d\n",
415 					 ctx->bufcnt, ctx->digcnt, final);
416 
417 	if (final || (ctx->bufcnt == ctx->buflen && ctx->total)) {
418 		count = ctx->bufcnt;
419 		ctx->bufcnt = 0;
420 		return omap_sham_xmit_dma_map(dd, ctx, count, final);
421 	}
422 
423 	return 0;
424 }
425 
426 /* Start address alignment */
427 #define SG_AA(sg)	(IS_ALIGNED(sg->offset, sizeof(u32)))
428 /* SHA1 block size alignment */
429 #define SG_SA(sg)	(IS_ALIGNED(sg->length, SHA1_MD5_BLOCK_SIZE))
430 
431 static int omap_sham_update_dma_start(struct omap_sham_dev *dd)
432 {
433 	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
434 	unsigned int length, final, tail;
435 	struct scatterlist *sg;
436 
437 	if (!ctx->total)
438 		return 0;
439 
440 	if (ctx->bufcnt || ctx->offset)
441 		return omap_sham_update_dma_slow(dd);
442 
443 	dev_dbg(dd->dev, "fast: digcnt: %d, bufcnt: %u, total: %u\n",
444 			ctx->digcnt, ctx->bufcnt, ctx->total);
445 
446 	sg = ctx->sg;
447 
448 	if (!SG_AA(sg))
449 		return omap_sham_update_dma_slow(dd);
450 
451 	if (!sg_is_last(sg) && !SG_SA(sg))
452 		/* size is not SHA1_BLOCK_SIZE aligned */
453 		return omap_sham_update_dma_slow(dd);
454 
455 	length = min(ctx->total, sg->length);
456 
457 	if (sg_is_last(sg)) {
458 		if (!(ctx->flags & BIT(FLAGS_FINUP))) {
459 			/* not last sg must be SHA1_MD5_BLOCK_SIZE aligned */
460 			tail = length & (SHA1_MD5_BLOCK_SIZE - 1);
461 			/* without finup() we need one block to close hash */
462 			if (!tail)
463 				tail = SHA1_MD5_BLOCK_SIZE;
464 			length -= tail;
465 		}
466 	}
467 
468 	if (!dma_map_sg(dd->dev, ctx->sg, 1, DMA_TO_DEVICE)) {
469 		dev_err(dd->dev, "dma_map_sg  error\n");
470 		return -EINVAL;
471 	}
472 
473 	ctx->flags |= BIT(FLAGS_SG);
474 
475 	ctx->total -= length;
476 	ctx->offset = length; /* offset where to start slow */
477 
478 	final = (ctx->flags & BIT(FLAGS_FINUP)) && !ctx->total;
479 
480 	/* next call does not fail... so no unmap in the case of error */
481 	return omap_sham_xmit_dma(dd, sg_dma_address(ctx->sg), length, final);
482 }
483 
484 static int omap_sham_update_cpu(struct omap_sham_dev *dd)
485 {
486 	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
487 	int bufcnt;
488 
489 	omap_sham_append_sg(ctx);
490 	bufcnt = ctx->bufcnt;
491 	ctx->bufcnt = 0;
492 
493 	return omap_sham_xmit_cpu(dd, ctx->buffer, bufcnt, 1);
494 }
495 
496 static int omap_sham_update_dma_stop(struct omap_sham_dev *dd)
497 {
498 	struct omap_sham_reqctx *ctx = ahash_request_ctx(dd->req);
499 
500 	omap_stop_dma(dd->dma_lch);
501 	if (ctx->flags & BIT(FLAGS_SG)) {
502 		dma_unmap_sg(dd->dev, ctx->sg, 1, DMA_TO_DEVICE);
503 		if (ctx->sg->length == ctx->offset) {
504 			ctx->sg = sg_next(ctx->sg);
505 			if (ctx->sg)
506 				ctx->offset = 0;
507 		}
508 	} else {
509 		dma_unmap_single(dd->dev, ctx->dma_addr, ctx->buflen,
510 				 DMA_TO_DEVICE);
511 	}
512 
513 	return 0;
514 }
515 
516 static int omap_sham_init(struct ahash_request *req)
517 {
518 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
519 	struct omap_sham_ctx *tctx = crypto_ahash_ctx(tfm);
520 	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
521 	struct omap_sham_dev *dd = NULL, *tmp;
522 
523 	spin_lock_bh(&sham.lock);
524 	if (!tctx->dd) {
525 		list_for_each_entry(tmp, &sham.dev_list, list) {
526 			dd = tmp;
527 			break;
528 		}
529 		tctx->dd = dd;
530 	} else {
531 		dd = tctx->dd;
532 	}
533 	spin_unlock_bh(&sham.lock);
534 
535 	ctx->dd = dd;
536 
537 	ctx->flags = 0;
538 
539 	dev_dbg(dd->dev, "init: digest size: %d\n",
540 		crypto_ahash_digestsize(tfm));
541 
542 	if (crypto_ahash_digestsize(tfm) == SHA1_DIGEST_SIZE)
543 		ctx->flags |= BIT(FLAGS_SHA1);
544 
545 	ctx->bufcnt = 0;
546 	ctx->digcnt = 0;
547 	ctx->buflen = BUFLEN;
548 
549 	if (tctx->flags & BIT(FLAGS_HMAC)) {
550 		struct omap_sham_hmac_ctx *bctx = tctx->base;
551 
552 		memcpy(ctx->buffer, bctx->ipad, SHA1_MD5_BLOCK_SIZE);
553 		ctx->bufcnt = SHA1_MD5_BLOCK_SIZE;
554 		ctx->flags |= BIT(FLAGS_HMAC);
555 	}
556 
557 	return 0;
558 
559 }
560 
561 static int omap_sham_update_req(struct omap_sham_dev *dd)
562 {
563 	struct ahash_request *req = dd->req;
564 	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
565 	int err;
566 
567 	dev_dbg(dd->dev, "update_req: total: %u, digcnt: %d, finup: %d\n",
568 		 ctx->total, ctx->digcnt, (ctx->flags & BIT(FLAGS_FINUP)) != 0);
569 
570 	if (ctx->flags & BIT(FLAGS_CPU))
571 		err = omap_sham_update_cpu(dd);
572 	else
573 		err = omap_sham_update_dma_start(dd);
574 
575 	/* wait for dma completion before can take more data */
576 	dev_dbg(dd->dev, "update: err: %d, digcnt: %d\n", err, ctx->digcnt);
577 
578 	return err;
579 }
580 
581 static int omap_sham_final_req(struct omap_sham_dev *dd)
582 {
583 	struct ahash_request *req = dd->req;
584 	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
585 	int err = 0, use_dma = 1;
586 
587 	if (ctx->bufcnt <= 64)
588 		/* faster to handle last block with cpu */
589 		use_dma = 0;
590 
591 	if (use_dma)
592 		err = omap_sham_xmit_dma_map(dd, ctx, ctx->bufcnt, 1);
593 	else
594 		err = omap_sham_xmit_cpu(dd, ctx->buffer, ctx->bufcnt, 1);
595 
596 	ctx->bufcnt = 0;
597 
598 	dev_dbg(dd->dev, "final_req: err: %d\n", err);
599 
600 	return err;
601 }
602 
603 static int omap_sham_finish_hmac(struct ahash_request *req)
604 {
605 	struct omap_sham_ctx *tctx = crypto_tfm_ctx(req->base.tfm);
606 	struct omap_sham_hmac_ctx *bctx = tctx->base;
607 	int bs = crypto_shash_blocksize(bctx->shash);
608 	int ds = crypto_shash_digestsize(bctx->shash);
609 	struct {
610 		struct shash_desc shash;
611 		char ctx[crypto_shash_descsize(bctx->shash)];
612 	} desc;
613 
614 	desc.shash.tfm = bctx->shash;
615 	desc.shash.flags = 0; /* not CRYPTO_TFM_REQ_MAY_SLEEP */
616 
617 	return crypto_shash_init(&desc.shash) ?:
618 	       crypto_shash_update(&desc.shash, bctx->opad, bs) ?:
619 	       crypto_shash_finup(&desc.shash, req->result, ds, req->result);
620 }
621 
622 static int omap_sham_finish(struct ahash_request *req)
623 {
624 	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
625 	struct omap_sham_dev *dd = ctx->dd;
626 	int err = 0;
627 
628 	if (ctx->digcnt) {
629 		omap_sham_copy_ready_hash(req);
630 		if (ctx->flags & BIT(FLAGS_HMAC))
631 			err = omap_sham_finish_hmac(req);
632 	}
633 
634 	dev_dbg(dd->dev, "digcnt: %d, bufcnt: %d\n", ctx->digcnt, ctx->bufcnt);
635 
636 	return err;
637 }
638 
639 static void omap_sham_finish_req(struct ahash_request *req, int err)
640 {
641 	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
642 	struct omap_sham_dev *dd = ctx->dd;
643 
644 	if (!err) {
645 		omap_sham_copy_hash(req, 1);
646 		if (test_bit(FLAGS_FINAL, &dd->flags))
647 			err = omap_sham_finish(req);
648 	} else {
649 		ctx->flags |= BIT(FLAGS_ERROR);
650 	}
651 
652 	/* atomic operation is not needed here */
653 	dd->flags &= ~(BIT(FLAGS_BUSY) | BIT(FLAGS_FINAL) | BIT(FLAGS_CPU) |
654 			BIT(FLAGS_DMA_READY) | BIT(FLAGS_OUTPUT_READY));
655 	clk_disable(dd->iclk);
656 
657 	if (req->base.complete)
658 		req->base.complete(&req->base, err);
659 
660 	/* handle new request */
661 	tasklet_schedule(&dd->done_task);
662 }
663 
664 static int omap_sham_handle_queue(struct omap_sham_dev *dd,
665 				  struct ahash_request *req)
666 {
667 	struct crypto_async_request *async_req, *backlog;
668 	struct omap_sham_reqctx *ctx;
669 	unsigned long flags;
670 	int err = 0, ret = 0;
671 
672 	spin_lock_irqsave(&dd->lock, flags);
673 	if (req)
674 		ret = ahash_enqueue_request(&dd->queue, req);
675 	if (test_bit(FLAGS_BUSY, &dd->flags)) {
676 		spin_unlock_irqrestore(&dd->lock, flags);
677 		return ret;
678 	}
679 	backlog = crypto_get_backlog(&dd->queue);
680 	async_req = crypto_dequeue_request(&dd->queue);
681 	if (async_req)
682 		set_bit(FLAGS_BUSY, &dd->flags);
683 	spin_unlock_irqrestore(&dd->lock, flags);
684 
685 	if (!async_req)
686 		return ret;
687 
688 	if (backlog)
689 		backlog->complete(backlog, -EINPROGRESS);
690 
691 	req = ahash_request_cast(async_req);
692 	dd->req = req;
693 	ctx = ahash_request_ctx(req);
694 
695 	dev_dbg(dd->dev, "handling new req, op: %lu, nbytes: %d\n",
696 						ctx->op, req->nbytes);
697 
698 	err = omap_sham_hw_init(dd);
699 	if (err)
700 		goto err1;
701 
702 	omap_set_dma_dest_params(dd->dma_lch, 0,
703 			OMAP_DMA_AMODE_CONSTANT,
704 			dd->phys_base + SHA_REG_DIN(0), 0, 16);
705 
706 	omap_set_dma_dest_burst_mode(dd->dma_lch,
707 			OMAP_DMA_DATA_BURST_16);
708 
709 	omap_set_dma_src_burst_mode(dd->dma_lch,
710 			OMAP_DMA_DATA_BURST_4);
711 
712 	if (ctx->digcnt)
713 		/* request has changed - restore hash */
714 		omap_sham_copy_hash(req, 0);
715 
716 	if (ctx->op == OP_UPDATE) {
717 		err = omap_sham_update_req(dd);
718 		if (err != -EINPROGRESS && (ctx->flags & BIT(FLAGS_FINUP)))
719 			/* no final() after finup() */
720 			err = omap_sham_final_req(dd);
721 	} else if (ctx->op == OP_FINAL) {
722 		err = omap_sham_final_req(dd);
723 	}
724 err1:
725 	if (err != -EINPROGRESS)
726 		/* done_task will not finish it, so do it here */
727 		omap_sham_finish_req(req, err);
728 
729 	dev_dbg(dd->dev, "exit, err: %d\n", err);
730 
731 	return ret;
732 }
733 
734 static int omap_sham_enqueue(struct ahash_request *req, unsigned int op)
735 {
736 	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
737 	struct omap_sham_ctx *tctx = crypto_tfm_ctx(req->base.tfm);
738 	struct omap_sham_dev *dd = tctx->dd;
739 
740 	ctx->op = op;
741 
742 	return omap_sham_handle_queue(dd, req);
743 }
744 
745 static int omap_sham_update(struct ahash_request *req)
746 {
747 	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
748 
749 	if (!req->nbytes)
750 		return 0;
751 
752 	ctx->total = req->nbytes;
753 	ctx->sg = req->src;
754 	ctx->offset = 0;
755 
756 	if (ctx->flags & BIT(FLAGS_FINUP)) {
757 		if ((ctx->digcnt + ctx->bufcnt + ctx->total) < 9) {
758 			/*
759 			* OMAP HW accel works only with buffers >= 9
760 			* will switch to bypass in final()
761 			* final has the same request and data
762 			*/
763 			omap_sham_append_sg(ctx);
764 			return 0;
765 		} else if (ctx->bufcnt + ctx->total <= SHA1_MD5_BLOCK_SIZE) {
766 			/*
767 			* faster to use CPU for short transfers
768 			*/
769 			ctx->flags |= BIT(FLAGS_CPU);
770 		}
771 	} else if (ctx->bufcnt + ctx->total < ctx->buflen) {
772 		omap_sham_append_sg(ctx);
773 		return 0;
774 	}
775 
776 	return omap_sham_enqueue(req, OP_UPDATE);
777 }
778 
779 static int omap_sham_shash_digest(struct crypto_shash *shash, u32 flags,
780 				  const u8 *data, unsigned int len, u8 *out)
781 {
782 	struct {
783 		struct shash_desc shash;
784 		char ctx[crypto_shash_descsize(shash)];
785 	} desc;
786 
787 	desc.shash.tfm = shash;
788 	desc.shash.flags = flags & CRYPTO_TFM_REQ_MAY_SLEEP;
789 
790 	return crypto_shash_digest(&desc.shash, data, len, out);
791 }
792 
793 static int omap_sham_final_shash(struct ahash_request *req)
794 {
795 	struct omap_sham_ctx *tctx = crypto_tfm_ctx(req->base.tfm);
796 	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
797 
798 	return omap_sham_shash_digest(tctx->fallback, req->base.flags,
799 				      ctx->buffer, ctx->bufcnt, req->result);
800 }
801 
802 static int omap_sham_final(struct ahash_request *req)
803 {
804 	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
805 
806 	ctx->flags |= BIT(FLAGS_FINUP);
807 
808 	if (ctx->flags & BIT(FLAGS_ERROR))
809 		return 0; /* uncompleted hash is not needed */
810 
811 	/* OMAP HW accel works only with buffers >= 9 */
812 	/* HMAC is always >= 9 because ipad == block size */
813 	if ((ctx->digcnt + ctx->bufcnt) < 9)
814 		return omap_sham_final_shash(req);
815 	else if (ctx->bufcnt)
816 		return omap_sham_enqueue(req, OP_FINAL);
817 
818 	/* copy ready hash (+ finalize hmac) */
819 	return omap_sham_finish(req);
820 }
821 
822 static int omap_sham_finup(struct ahash_request *req)
823 {
824 	struct omap_sham_reqctx *ctx = ahash_request_ctx(req);
825 	int err1, err2;
826 
827 	ctx->flags |= BIT(FLAGS_FINUP);
828 
829 	err1 = omap_sham_update(req);
830 	if (err1 == -EINPROGRESS || err1 == -EBUSY)
831 		return err1;
832 	/*
833 	 * final() has to be always called to cleanup resources
834 	 * even if udpate() failed, except EINPROGRESS
835 	 */
836 	err2 = omap_sham_final(req);
837 
838 	return err1 ?: err2;
839 }
840 
841 static int omap_sham_digest(struct ahash_request *req)
842 {
843 	return omap_sham_init(req) ?: omap_sham_finup(req);
844 }
845 
846 static int omap_sham_setkey(struct crypto_ahash *tfm, const u8 *key,
847 		      unsigned int keylen)
848 {
849 	struct omap_sham_ctx *tctx = crypto_ahash_ctx(tfm);
850 	struct omap_sham_hmac_ctx *bctx = tctx->base;
851 	int bs = crypto_shash_blocksize(bctx->shash);
852 	int ds = crypto_shash_digestsize(bctx->shash);
853 	int err, i;
854 	err = crypto_shash_setkey(tctx->fallback, key, keylen);
855 	if (err)
856 		return err;
857 
858 	if (keylen > bs) {
859 		err = omap_sham_shash_digest(bctx->shash,
860 				crypto_shash_get_flags(bctx->shash),
861 				key, keylen, bctx->ipad);
862 		if (err)
863 			return err;
864 		keylen = ds;
865 	} else {
866 		memcpy(bctx->ipad, key, keylen);
867 	}
868 
869 	memset(bctx->ipad + keylen, 0, bs - keylen);
870 	memcpy(bctx->opad, bctx->ipad, bs);
871 
872 	for (i = 0; i < bs; i++) {
873 		bctx->ipad[i] ^= 0x36;
874 		bctx->opad[i] ^= 0x5c;
875 	}
876 
877 	return err;
878 }
879 
880 static int omap_sham_cra_init_alg(struct crypto_tfm *tfm, const char *alg_base)
881 {
882 	struct omap_sham_ctx *tctx = crypto_tfm_ctx(tfm);
883 	const char *alg_name = crypto_tfm_alg_name(tfm);
884 
885 	/* Allocate a fallback and abort if it failed. */
886 	tctx->fallback = crypto_alloc_shash(alg_name, 0,
887 					    CRYPTO_ALG_NEED_FALLBACK);
888 	if (IS_ERR(tctx->fallback)) {
889 		pr_err("omap-sham: fallback driver '%s' "
890 				"could not be loaded.\n", alg_name);
891 		return PTR_ERR(tctx->fallback);
892 	}
893 
894 	crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
895 				 sizeof(struct omap_sham_reqctx) + BUFLEN);
896 
897 	if (alg_base) {
898 		struct omap_sham_hmac_ctx *bctx = tctx->base;
899 		tctx->flags |= BIT(FLAGS_HMAC);
900 		bctx->shash = crypto_alloc_shash(alg_base, 0,
901 						CRYPTO_ALG_NEED_FALLBACK);
902 		if (IS_ERR(bctx->shash)) {
903 			pr_err("omap-sham: base driver '%s' "
904 					"could not be loaded.\n", alg_base);
905 			crypto_free_shash(tctx->fallback);
906 			return PTR_ERR(bctx->shash);
907 		}
908 
909 	}
910 
911 	return 0;
912 }
913 
914 static int omap_sham_cra_init(struct crypto_tfm *tfm)
915 {
916 	return omap_sham_cra_init_alg(tfm, NULL);
917 }
918 
919 static int omap_sham_cra_sha1_init(struct crypto_tfm *tfm)
920 {
921 	return omap_sham_cra_init_alg(tfm, "sha1");
922 }
923 
924 static int omap_sham_cra_md5_init(struct crypto_tfm *tfm)
925 {
926 	return omap_sham_cra_init_alg(tfm, "md5");
927 }
928 
929 static void omap_sham_cra_exit(struct crypto_tfm *tfm)
930 {
931 	struct omap_sham_ctx *tctx = crypto_tfm_ctx(tfm);
932 
933 	crypto_free_shash(tctx->fallback);
934 	tctx->fallback = NULL;
935 
936 	if (tctx->flags & BIT(FLAGS_HMAC)) {
937 		struct omap_sham_hmac_ctx *bctx = tctx->base;
938 		crypto_free_shash(bctx->shash);
939 	}
940 }
941 
942 static struct ahash_alg algs[] = {
943 {
944 	.init		= omap_sham_init,
945 	.update		= omap_sham_update,
946 	.final		= omap_sham_final,
947 	.finup		= omap_sham_finup,
948 	.digest		= omap_sham_digest,
949 	.halg.digestsize	= SHA1_DIGEST_SIZE,
950 	.halg.base	= {
951 		.cra_name		= "sha1",
952 		.cra_driver_name	= "omap-sha1",
953 		.cra_priority		= 100,
954 		.cra_flags		= CRYPTO_ALG_TYPE_AHASH |
955 						CRYPTO_ALG_KERN_DRIVER_ONLY |
956 						CRYPTO_ALG_ASYNC |
957 						CRYPTO_ALG_NEED_FALLBACK,
958 		.cra_blocksize		= SHA1_BLOCK_SIZE,
959 		.cra_ctxsize		= sizeof(struct omap_sham_ctx),
960 		.cra_alignmask		= 0,
961 		.cra_module		= THIS_MODULE,
962 		.cra_init		= omap_sham_cra_init,
963 		.cra_exit		= omap_sham_cra_exit,
964 	}
965 },
966 {
967 	.init		= omap_sham_init,
968 	.update		= omap_sham_update,
969 	.final		= omap_sham_final,
970 	.finup		= omap_sham_finup,
971 	.digest		= omap_sham_digest,
972 	.halg.digestsize	= MD5_DIGEST_SIZE,
973 	.halg.base	= {
974 		.cra_name		= "md5",
975 		.cra_driver_name	= "omap-md5",
976 		.cra_priority		= 100,
977 		.cra_flags		= CRYPTO_ALG_TYPE_AHASH |
978 						CRYPTO_ALG_KERN_DRIVER_ONLY |
979 						CRYPTO_ALG_ASYNC |
980 						CRYPTO_ALG_NEED_FALLBACK,
981 		.cra_blocksize		= SHA1_BLOCK_SIZE,
982 		.cra_ctxsize		= sizeof(struct omap_sham_ctx),
983 		.cra_alignmask		= OMAP_ALIGN_MASK,
984 		.cra_module		= THIS_MODULE,
985 		.cra_init		= omap_sham_cra_init,
986 		.cra_exit		= omap_sham_cra_exit,
987 	}
988 },
989 {
990 	.init		= omap_sham_init,
991 	.update		= omap_sham_update,
992 	.final		= omap_sham_final,
993 	.finup		= omap_sham_finup,
994 	.digest		= omap_sham_digest,
995 	.setkey		= omap_sham_setkey,
996 	.halg.digestsize	= SHA1_DIGEST_SIZE,
997 	.halg.base	= {
998 		.cra_name		= "hmac(sha1)",
999 		.cra_driver_name	= "omap-hmac-sha1",
1000 		.cra_priority		= 100,
1001 		.cra_flags		= CRYPTO_ALG_TYPE_AHASH |
1002 						CRYPTO_ALG_KERN_DRIVER_ONLY |
1003 						CRYPTO_ALG_ASYNC |
1004 						CRYPTO_ALG_NEED_FALLBACK,
1005 		.cra_blocksize		= SHA1_BLOCK_SIZE,
1006 		.cra_ctxsize		= sizeof(struct omap_sham_ctx) +
1007 					sizeof(struct omap_sham_hmac_ctx),
1008 		.cra_alignmask		= OMAP_ALIGN_MASK,
1009 		.cra_module		= THIS_MODULE,
1010 		.cra_init		= omap_sham_cra_sha1_init,
1011 		.cra_exit		= omap_sham_cra_exit,
1012 	}
1013 },
1014 {
1015 	.init		= omap_sham_init,
1016 	.update		= omap_sham_update,
1017 	.final		= omap_sham_final,
1018 	.finup		= omap_sham_finup,
1019 	.digest		= omap_sham_digest,
1020 	.setkey		= omap_sham_setkey,
1021 	.halg.digestsize	= MD5_DIGEST_SIZE,
1022 	.halg.base	= {
1023 		.cra_name		= "hmac(md5)",
1024 		.cra_driver_name	= "omap-hmac-md5",
1025 		.cra_priority		= 100,
1026 		.cra_flags		= CRYPTO_ALG_TYPE_AHASH |
1027 						CRYPTO_ALG_KERN_DRIVER_ONLY |
1028 						CRYPTO_ALG_ASYNC |
1029 						CRYPTO_ALG_NEED_FALLBACK,
1030 		.cra_blocksize		= SHA1_BLOCK_SIZE,
1031 		.cra_ctxsize		= sizeof(struct omap_sham_ctx) +
1032 					sizeof(struct omap_sham_hmac_ctx),
1033 		.cra_alignmask		= OMAP_ALIGN_MASK,
1034 		.cra_module		= THIS_MODULE,
1035 		.cra_init		= omap_sham_cra_md5_init,
1036 		.cra_exit		= omap_sham_cra_exit,
1037 	}
1038 }
1039 };
1040 
1041 static void omap_sham_done_task(unsigned long data)
1042 {
1043 	struct omap_sham_dev *dd = (struct omap_sham_dev *)data;
1044 	int err = 0;
1045 
1046 	if (!test_bit(FLAGS_BUSY, &dd->flags)) {
1047 		omap_sham_handle_queue(dd, NULL);
1048 		return;
1049 	}
1050 
1051 	if (test_bit(FLAGS_CPU, &dd->flags)) {
1052 		if (test_and_clear_bit(FLAGS_OUTPUT_READY, &dd->flags))
1053 			goto finish;
1054 	} else if (test_bit(FLAGS_DMA_READY, &dd->flags)) {
1055 		if (test_and_clear_bit(FLAGS_DMA_ACTIVE, &dd->flags)) {
1056 			omap_sham_update_dma_stop(dd);
1057 			if (dd->err) {
1058 				err = dd->err;
1059 				goto finish;
1060 			}
1061 		}
1062 		if (test_and_clear_bit(FLAGS_OUTPUT_READY, &dd->flags)) {
1063 			/* hash or semi-hash ready */
1064 			clear_bit(FLAGS_DMA_READY, &dd->flags);
1065 			err = omap_sham_update_dma_start(dd);
1066 			if (err != -EINPROGRESS)
1067 				goto finish;
1068 		}
1069 	}
1070 
1071 	return;
1072 
1073 finish:
1074 	dev_dbg(dd->dev, "update done: err: %d\n", err);
1075 	/* finish curent request */
1076 	omap_sham_finish_req(dd->req, err);
1077 }
1078 
1079 static irqreturn_t omap_sham_irq(int irq, void *dev_id)
1080 {
1081 	struct omap_sham_dev *dd = dev_id;
1082 
1083 	if (unlikely(test_bit(FLAGS_FINAL, &dd->flags)))
1084 		/* final -> allow device to go to power-saving mode */
1085 		omap_sham_write_mask(dd, SHA_REG_CTRL, 0, SHA_REG_CTRL_LENGTH);
1086 
1087 	omap_sham_write_mask(dd, SHA_REG_CTRL, SHA_REG_CTRL_OUTPUT_READY,
1088 				 SHA_REG_CTRL_OUTPUT_READY);
1089 	omap_sham_read(dd, SHA_REG_CTRL);
1090 
1091 	if (!test_bit(FLAGS_BUSY, &dd->flags)) {
1092 		dev_warn(dd->dev, "Interrupt when no active requests.\n");
1093 		return IRQ_HANDLED;
1094 	}
1095 
1096 	set_bit(FLAGS_OUTPUT_READY, &dd->flags);
1097 	tasklet_schedule(&dd->done_task);
1098 
1099 	return IRQ_HANDLED;
1100 }
1101 
1102 static void omap_sham_dma_callback(int lch, u16 ch_status, void *data)
1103 {
1104 	struct omap_sham_dev *dd = data;
1105 
1106 	if (ch_status != OMAP_DMA_BLOCK_IRQ) {
1107 		pr_err("omap-sham DMA error status: 0x%hx\n", ch_status);
1108 		dd->err = -EIO;
1109 		clear_bit(FLAGS_INIT, &dd->flags);/* request to re-initialize */
1110 	}
1111 
1112 	set_bit(FLAGS_DMA_READY, &dd->flags);
1113 	tasklet_schedule(&dd->done_task);
1114 }
1115 
1116 static int omap_sham_dma_init(struct omap_sham_dev *dd)
1117 {
1118 	int err;
1119 
1120 	dd->dma_lch = -1;
1121 
1122 	err = omap_request_dma(dd->dma, dev_name(dd->dev),
1123 			omap_sham_dma_callback, dd, &dd->dma_lch);
1124 	if (err) {
1125 		dev_err(dd->dev, "Unable to request DMA channel\n");
1126 		return err;
1127 	}
1128 
1129 	return 0;
1130 }
1131 
1132 static void omap_sham_dma_cleanup(struct omap_sham_dev *dd)
1133 {
1134 	if (dd->dma_lch >= 0) {
1135 		omap_free_dma(dd->dma_lch);
1136 		dd->dma_lch = -1;
1137 	}
1138 }
1139 
1140 static int __devinit omap_sham_probe(struct platform_device *pdev)
1141 {
1142 	struct omap_sham_dev *dd;
1143 	struct device *dev = &pdev->dev;
1144 	struct resource *res;
1145 	int err, i, j;
1146 
1147 	dd = kzalloc(sizeof(struct omap_sham_dev), GFP_KERNEL);
1148 	if (dd == NULL) {
1149 		dev_err(dev, "unable to alloc data struct.\n");
1150 		err = -ENOMEM;
1151 		goto data_err;
1152 	}
1153 	dd->dev = dev;
1154 	platform_set_drvdata(pdev, dd);
1155 
1156 	INIT_LIST_HEAD(&dd->list);
1157 	spin_lock_init(&dd->lock);
1158 	tasklet_init(&dd->done_task, omap_sham_done_task, (unsigned long)dd);
1159 	crypto_init_queue(&dd->queue, OMAP_SHAM_QUEUE_LENGTH);
1160 
1161 	dd->irq = -1;
1162 
1163 	/* Get the base address */
1164 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1165 	if (!res) {
1166 		dev_err(dev, "no MEM resource info\n");
1167 		err = -ENODEV;
1168 		goto res_err;
1169 	}
1170 	dd->phys_base = res->start;
1171 
1172 	/* Get the DMA */
1173 	res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1174 	if (!res) {
1175 		dev_err(dev, "no DMA resource info\n");
1176 		err = -ENODEV;
1177 		goto res_err;
1178 	}
1179 	dd->dma = res->start;
1180 
1181 	/* Get the IRQ */
1182 	dd->irq = platform_get_irq(pdev,  0);
1183 	if (dd->irq < 0) {
1184 		dev_err(dev, "no IRQ resource info\n");
1185 		err = dd->irq;
1186 		goto res_err;
1187 	}
1188 
1189 	err = request_irq(dd->irq, omap_sham_irq,
1190 			IRQF_TRIGGER_LOW, dev_name(dev), dd);
1191 	if (err) {
1192 		dev_err(dev, "unable to request irq.\n");
1193 		goto res_err;
1194 	}
1195 
1196 	err = omap_sham_dma_init(dd);
1197 	if (err)
1198 		goto dma_err;
1199 
1200 	/* Initializing the clock */
1201 	dd->iclk = clk_get(dev, "ick");
1202 	if (IS_ERR(dd->iclk)) {
1203 		dev_err(dev, "clock intialization failed.\n");
1204 		err = PTR_ERR(dd->iclk);
1205 		goto clk_err;
1206 	}
1207 
1208 	dd->io_base = ioremap(dd->phys_base, SZ_4K);
1209 	if (!dd->io_base) {
1210 		dev_err(dev, "can't ioremap\n");
1211 		err = -ENOMEM;
1212 		goto io_err;
1213 	}
1214 
1215 	clk_enable(dd->iclk);
1216 	dev_info(dev, "hw accel on OMAP rev %u.%u\n",
1217 		(omap_sham_read(dd, SHA_REG_REV) & SHA_REG_REV_MAJOR) >> 4,
1218 		omap_sham_read(dd, SHA_REG_REV) & SHA_REG_REV_MINOR);
1219 	clk_disable(dd->iclk);
1220 
1221 	spin_lock(&sham.lock);
1222 	list_add_tail(&dd->list, &sham.dev_list);
1223 	spin_unlock(&sham.lock);
1224 
1225 	for (i = 0; i < ARRAY_SIZE(algs); i++) {
1226 		err = crypto_register_ahash(&algs[i]);
1227 		if (err)
1228 			goto err_algs;
1229 	}
1230 
1231 	return 0;
1232 
1233 err_algs:
1234 	for (j = 0; j < i; j++)
1235 		crypto_unregister_ahash(&algs[j]);
1236 	iounmap(dd->io_base);
1237 io_err:
1238 	clk_put(dd->iclk);
1239 clk_err:
1240 	omap_sham_dma_cleanup(dd);
1241 dma_err:
1242 	if (dd->irq >= 0)
1243 		free_irq(dd->irq, dd);
1244 res_err:
1245 	kfree(dd);
1246 	dd = NULL;
1247 data_err:
1248 	dev_err(dev, "initialization failed.\n");
1249 
1250 	return err;
1251 }
1252 
1253 static int __devexit omap_sham_remove(struct platform_device *pdev)
1254 {
1255 	static struct omap_sham_dev *dd;
1256 	int i;
1257 
1258 	dd = platform_get_drvdata(pdev);
1259 	if (!dd)
1260 		return -ENODEV;
1261 	spin_lock(&sham.lock);
1262 	list_del(&dd->list);
1263 	spin_unlock(&sham.lock);
1264 	for (i = 0; i < ARRAY_SIZE(algs); i++)
1265 		crypto_unregister_ahash(&algs[i]);
1266 	tasklet_kill(&dd->done_task);
1267 	iounmap(dd->io_base);
1268 	clk_put(dd->iclk);
1269 	omap_sham_dma_cleanup(dd);
1270 	if (dd->irq >= 0)
1271 		free_irq(dd->irq, dd);
1272 	kfree(dd);
1273 	dd = NULL;
1274 
1275 	return 0;
1276 }
1277 
1278 static struct platform_driver omap_sham_driver = {
1279 	.probe	= omap_sham_probe,
1280 	.remove	= omap_sham_remove,
1281 	.driver	= {
1282 		.name	= "omap-sham",
1283 		.owner	= THIS_MODULE,
1284 	},
1285 };
1286 
1287 static int __init omap_sham_mod_init(void)
1288 {
1289 	pr_info("loading %s driver\n", "omap-sham");
1290 
1291 	return platform_driver_register(&omap_sham_driver);
1292 }
1293 
1294 static void __exit omap_sham_mod_exit(void)
1295 {
1296 	platform_driver_unregister(&omap_sham_driver);
1297 }
1298 
1299 module_init(omap_sham_mod_init);
1300 module_exit(omap_sham_mod_exit);
1301 
1302 MODULE_DESCRIPTION("OMAP SHA1/MD5 hw acceleration support.");
1303 MODULE_LICENSE("GPL v2");
1304 MODULE_AUTHOR("Dmitry Kasatkin");
1305