xref: /linux/drivers/mtd/nand/ecc-mtk.c (revision fab183d632628381b466a41479489541ac0e29a0)
1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /*
3  * MTK ECC controller driver.
4  * Copyright (C) 2016  MediaTek Inc.
5  * Authors:	Xiaolei Li		<xiaolei.li@mediatek.com>
6  *		Jorge Ramirez-Ortiz	<jorge.ramirez-ortiz@linaro.org>
7  */
8 
9 #include <linux/platform_device.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/interrupt.h>
12 #include <linux/clk.h>
13 #include <linux/module.h>
14 #include <linux/iopoll.h>
15 #include <linux/of.h>
16 #include <linux/of_platform.h>
17 #include <linux/mutex.h>
18 #include <linux/mtd/nand-ecc-mtk.h>
19 
20 #define ECC_IDLE_MASK		BIT(0)
21 #define ECC_IRQ_EN		BIT(0)
22 #define ECC_PG_IRQ_SEL		BIT(1)
23 #define ECC_OP_ENABLE		(1)
24 #define ECC_OP_DISABLE		(0)
25 
26 #define ECC_ENCCON		(0x00)
27 #define ECC_ENCCNFG		(0x04)
28 #define		ECC_MS_SHIFT		(16)
29 #define ECC_ENCDIADDR		(0x08)
30 #define ECC_ENCIDLE		(0x0C)
31 #define ECC_DECCON		(0x100)
32 #define ECC_DECCNFG		(0x104)
33 #define		DEC_EMPTY_EN		BIT(31)
34 #define		DEC_CNFG_CORRECT	(0x3 << 12)
35 #define ECC_DECIDLE		(0x10C)
36 #define ECC_DECENUM0		(0x114)
37 
38 #define ECC_TIMEOUT		(500000)
39 
40 #define ECC_IDLE_REG(op)	((op) == ECC_ENCODE ? ECC_ENCIDLE : ECC_DECIDLE)
41 #define ECC_CTL_REG(op)		((op) == ECC_ENCODE ? ECC_ENCCON : ECC_DECCON)
42 
43 #define ECC_ERRMASK_MT7622	GENMASK(4, 0)
44 #define ECC_ERRMASK_MT2701	GENMASK(5, 0)
45 #define ECC_ERRMASK_MT2712	GENMASK(6, 0)
46 
47 struct mtk_ecc_caps {
48 	u32 err_mask;
49 	u32 err_shift;
50 	const u8 *ecc_strength;
51 	const u32 *ecc_regs;
52 	u8 num_ecc_strength;
53 	u8 ecc_mode_shift;
54 	u32 parity_bits;
55 	int pg_irq_sel;
56 };
57 
58 struct mtk_ecc {
59 	struct device *dev;
60 	const struct mtk_ecc_caps *caps;
61 	void __iomem *regs;
62 	struct clk *clk;
63 
64 	struct completion done;
65 	struct mutex lock;
66 	u32 sectors;
67 
68 	u8 *eccdata;
69 };
70 
71 /* ecc strength that each IP supports */
72 static const u8 ecc_strength_mt2701[] = {
73 	4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 28, 32, 36,
74 	40, 44, 48, 52, 56, 60
75 };
76 
77 static const u8 ecc_strength_mt2712[] = {
78 	4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 28, 32, 36,
79 	40, 44, 48, 52, 56, 60, 68, 72, 80
80 };
81 
82 static const u8 ecc_strength_mt7622[] = {
83 	4, 6, 8, 10, 12
84 };
85 
86 static const u8 ecc_strength_mt7986[] = {
87 	4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24
88 };
89 
90 enum mtk_ecc_regs {
91 	ECC_ENCPAR00,
92 	ECC_ENCIRQ_EN,
93 	ECC_ENCIRQ_STA,
94 	ECC_DECDONE,
95 	ECC_DECIRQ_EN,
96 	ECC_DECIRQ_STA,
97 };
98 
99 static int mt2701_ecc_regs[] = {
100 	[ECC_ENCPAR00] =        0x10,
101 	[ECC_ENCIRQ_EN] =       0x80,
102 	[ECC_ENCIRQ_STA] =      0x84,
103 	[ECC_DECDONE] =         0x124,
104 	[ECC_DECIRQ_EN] =       0x200,
105 	[ECC_DECIRQ_STA] =      0x204,
106 };
107 
108 static int mt2712_ecc_regs[] = {
109 	[ECC_ENCPAR00] =        0x300,
110 	[ECC_ENCIRQ_EN] =       0x80,
111 	[ECC_ENCIRQ_STA] =      0x84,
112 	[ECC_DECDONE] =         0x124,
113 	[ECC_DECIRQ_EN] =       0x200,
114 	[ECC_DECIRQ_STA] =      0x204,
115 };
116 
117 static int mt7622_ecc_regs[] = {
118 	[ECC_ENCPAR00] =        0x10,
119 	[ECC_ENCIRQ_EN] =       0x30,
120 	[ECC_ENCIRQ_STA] =      0x34,
121 	[ECC_DECDONE] =         0x11c,
122 	[ECC_DECIRQ_EN] =       0x140,
123 	[ECC_DECIRQ_STA] =      0x144,
124 };
125 
mtk_ecc_wait_idle(struct mtk_ecc * ecc,enum mtk_ecc_operation op)126 static inline int mtk_ecc_wait_idle(struct mtk_ecc *ecc,
127 				    enum mtk_ecc_operation op)
128 {
129 	struct device *dev = ecc->dev;
130 	u32 val;
131 	int ret;
132 
133 	ret = readl_poll_timeout_atomic(ecc->regs + ECC_IDLE_REG(op), val,
134 					val & ECC_IDLE_MASK,
135 					10, ECC_TIMEOUT);
136 	if (ret)
137 		dev_warn(dev, "%s NOT idle\n",
138 			 op == ECC_ENCODE ? "encoder" : "decoder");
139 
140 	return ret;
141 }
142 
mtk_ecc_irq(int irq,void * id)143 static irqreturn_t mtk_ecc_irq(int irq, void *id)
144 {
145 	struct mtk_ecc *ecc = id;
146 	u32 dec, enc;
147 
148 	dec = readw(ecc->regs + ecc->caps->ecc_regs[ECC_DECIRQ_STA])
149 		    & ECC_IRQ_EN;
150 	if (dec) {
151 		dec = readw(ecc->regs + ecc->caps->ecc_regs[ECC_DECDONE]);
152 		if (dec & ecc->sectors) {
153 			/*
154 			 * Clear decode IRQ status once again to ensure that
155 			 * there will be no extra IRQ.
156 			 */
157 			readw(ecc->regs + ecc->caps->ecc_regs[ECC_DECIRQ_STA]);
158 			ecc->sectors = 0;
159 			complete(&ecc->done);
160 		} else {
161 			return IRQ_HANDLED;
162 		}
163 	} else {
164 		enc = readl(ecc->regs + ecc->caps->ecc_regs[ECC_ENCIRQ_STA])
165 		      & ECC_IRQ_EN;
166 		if (enc)
167 			complete(&ecc->done);
168 		else
169 			return IRQ_NONE;
170 	}
171 
172 	return IRQ_HANDLED;
173 }
174 
mtk_ecc_config(struct mtk_ecc * ecc,struct mtk_ecc_config * config)175 static int mtk_ecc_config(struct mtk_ecc *ecc, struct mtk_ecc_config *config)
176 {
177 	u32 ecc_bit, dec_sz, enc_sz;
178 	u32 reg, i;
179 
180 	for (i = 0; i < ecc->caps->num_ecc_strength; i++) {
181 		if (ecc->caps->ecc_strength[i] == config->strength)
182 			break;
183 	}
184 
185 	if (i == ecc->caps->num_ecc_strength) {
186 		dev_err(ecc->dev, "invalid ecc strength %d\n",
187 			config->strength);
188 		return -EINVAL;
189 	}
190 
191 	ecc_bit = i;
192 
193 	if (config->op == ECC_ENCODE) {
194 		/* configure ECC encoder (in bits) */
195 		enc_sz = config->len << 3;
196 
197 		reg = ecc_bit | (config->mode << ecc->caps->ecc_mode_shift);
198 		reg |= (enc_sz << ECC_MS_SHIFT);
199 		writel(reg, ecc->regs + ECC_ENCCNFG);
200 
201 		if (config->mode != ECC_NFI_MODE)
202 			writel(lower_32_bits(config->addr),
203 			       ecc->regs + ECC_ENCDIADDR);
204 
205 	} else {
206 		/* configure ECC decoder (in bits) */
207 		dec_sz = (config->len << 3) +
208 			 config->strength * ecc->caps->parity_bits;
209 
210 		reg = ecc_bit | (config->mode << ecc->caps->ecc_mode_shift);
211 		reg |= (dec_sz << ECC_MS_SHIFT) | DEC_CNFG_CORRECT;
212 		reg |= DEC_EMPTY_EN;
213 		writel(reg, ecc->regs + ECC_DECCNFG);
214 
215 		if (config->sectors)
216 			ecc->sectors = 1 << (config->sectors - 1);
217 	}
218 
219 	return 0;
220 }
221 
mtk_ecc_get_stats(struct mtk_ecc * ecc,struct mtk_ecc_stats * stats,int sectors)222 void mtk_ecc_get_stats(struct mtk_ecc *ecc, struct mtk_ecc_stats *stats,
223 		       int sectors)
224 {
225 	u32 offset, i, err;
226 	u32 bitflips = 0;
227 
228 	stats->corrected = 0;
229 	stats->failed = 0;
230 
231 	for (i = 0; i < sectors; i++) {
232 		offset = (i >> 2) << 2;
233 		err = readl(ecc->regs + ECC_DECENUM0 + offset);
234 		err = err >> ((i % 4) * ecc->caps->err_shift);
235 		err &= ecc->caps->err_mask;
236 		if (err == ecc->caps->err_mask) {
237 			/* uncorrectable errors */
238 			stats->failed++;
239 			continue;
240 		}
241 
242 		stats->corrected += err;
243 		bitflips = max_t(u32, bitflips, err);
244 	}
245 
246 	stats->bitflips = bitflips;
247 }
248 EXPORT_SYMBOL(mtk_ecc_get_stats);
249 
mtk_ecc_release(struct mtk_ecc * ecc)250 void mtk_ecc_release(struct mtk_ecc *ecc)
251 {
252 	clk_disable_unprepare(ecc->clk);
253 	put_device(ecc->dev);
254 }
255 EXPORT_SYMBOL(mtk_ecc_release);
256 
mtk_ecc_hw_init(struct mtk_ecc * ecc)257 static void mtk_ecc_hw_init(struct mtk_ecc *ecc)
258 {
259 	mtk_ecc_wait_idle(ecc, ECC_ENCODE);
260 	writew(ECC_OP_DISABLE, ecc->regs + ECC_ENCCON);
261 
262 	mtk_ecc_wait_idle(ecc, ECC_DECODE);
263 	writel(ECC_OP_DISABLE, ecc->regs + ECC_DECCON);
264 }
265 
mtk_ecc_get(struct device_node * np)266 static struct mtk_ecc *mtk_ecc_get(struct device_node *np)
267 {
268 	struct platform_device *pdev;
269 	struct mtk_ecc *ecc;
270 	int ret;
271 
272 	pdev = of_find_device_by_node(np);
273 	if (!pdev)
274 		return ERR_PTR(-EPROBE_DEFER);
275 
276 	ecc = platform_get_drvdata(pdev);
277 	if (!ecc) {
278 		put_device(&pdev->dev);
279 		return ERR_PTR(-EPROBE_DEFER);
280 	}
281 
282 	ret = clk_prepare_enable(ecc->clk);
283 	if (ret) {
284 		put_device(&pdev->dev);
285 		return ERR_PTR(ret);
286 	}
287 
288 	mtk_ecc_hw_init(ecc);
289 
290 	return ecc;
291 }
292 
of_mtk_ecc_get(struct device_node * of_node)293 struct mtk_ecc *of_mtk_ecc_get(struct device_node *of_node)
294 {
295 	struct mtk_ecc *ecc = NULL;
296 	struct device_node *np;
297 
298 	np = of_parse_phandle(of_node, "nand-ecc-engine", 0);
299 	/* for backward compatibility */
300 	if (!np)
301 		np = of_parse_phandle(of_node, "ecc-engine", 0);
302 	if (np) {
303 		ecc = mtk_ecc_get(np);
304 		of_node_put(np);
305 	}
306 
307 	return ecc;
308 }
309 EXPORT_SYMBOL(of_mtk_ecc_get);
310 
mtk_ecc_enable(struct mtk_ecc * ecc,struct mtk_ecc_config * config)311 int mtk_ecc_enable(struct mtk_ecc *ecc, struct mtk_ecc_config *config)
312 {
313 	enum mtk_ecc_operation op = config->op;
314 	u16 reg_val;
315 	int ret;
316 
317 	ret = mutex_lock_interruptible(&ecc->lock);
318 	if (ret) {
319 		dev_err(ecc->dev, "interrupted when attempting to lock\n");
320 		return ret;
321 	}
322 
323 	ret = mtk_ecc_wait_idle(ecc, op);
324 	if (ret) {
325 		mutex_unlock(&ecc->lock);
326 		return ret;
327 	}
328 
329 	ret = mtk_ecc_config(ecc, config);
330 	if (ret) {
331 		mutex_unlock(&ecc->lock);
332 		return ret;
333 	}
334 
335 	if (config->mode != ECC_NFI_MODE || op != ECC_ENCODE) {
336 		init_completion(&ecc->done);
337 		reg_val = ECC_IRQ_EN;
338 		/*
339 		 * For ECC_NFI_MODE, if ecc->caps->pg_irq_sel is 1, then it
340 		 * means this chip can only generate one ecc irq during page
341 		 * read / write. If is 0, generate one ecc irq each ecc step.
342 		 */
343 		if (ecc->caps->pg_irq_sel && config->mode == ECC_NFI_MODE)
344 			reg_val |= ECC_PG_IRQ_SEL;
345 		if (op == ECC_ENCODE)
346 			writew(reg_val, ecc->regs +
347 			       ecc->caps->ecc_regs[ECC_ENCIRQ_EN]);
348 		else
349 			writew(reg_val, ecc->regs +
350 			       ecc->caps->ecc_regs[ECC_DECIRQ_EN]);
351 	}
352 
353 	writew(ECC_OP_ENABLE, ecc->regs + ECC_CTL_REG(op));
354 
355 	return 0;
356 }
357 EXPORT_SYMBOL(mtk_ecc_enable);
358 
mtk_ecc_disable(struct mtk_ecc * ecc)359 void mtk_ecc_disable(struct mtk_ecc *ecc)
360 {
361 	enum mtk_ecc_operation op = ECC_ENCODE;
362 
363 	/* find out the running operation */
364 	if (readw(ecc->regs + ECC_CTL_REG(op)) != ECC_OP_ENABLE)
365 		op = ECC_DECODE;
366 
367 	/* disable it */
368 	mtk_ecc_wait_idle(ecc, op);
369 	if (op == ECC_DECODE) {
370 		/*
371 		 * Clear decode IRQ status in case there is a timeout to wait
372 		 * decode IRQ.
373 		 */
374 		readw(ecc->regs + ecc->caps->ecc_regs[ECC_DECDONE]);
375 		writew(0, ecc->regs + ecc->caps->ecc_regs[ECC_DECIRQ_EN]);
376 	} else {
377 		writew(0, ecc->regs + ecc->caps->ecc_regs[ECC_ENCIRQ_EN]);
378 	}
379 
380 	writew(ECC_OP_DISABLE, ecc->regs + ECC_CTL_REG(op));
381 
382 	mutex_unlock(&ecc->lock);
383 }
384 EXPORT_SYMBOL(mtk_ecc_disable);
385 
mtk_ecc_wait_done(struct mtk_ecc * ecc,enum mtk_ecc_operation op)386 int mtk_ecc_wait_done(struct mtk_ecc *ecc, enum mtk_ecc_operation op)
387 {
388 	int ret;
389 
390 	ret = wait_for_completion_timeout(&ecc->done, msecs_to_jiffies(500));
391 	if (!ret) {
392 		dev_err(ecc->dev, "%s timeout - interrupt did not arrive)\n",
393 			(op == ECC_ENCODE) ? "encoder" : "decoder");
394 		return -ETIMEDOUT;
395 	}
396 
397 	return 0;
398 }
399 EXPORT_SYMBOL(mtk_ecc_wait_done);
400 
mtk_ecc_encode(struct mtk_ecc * ecc,struct mtk_ecc_config * config,u8 * data,u32 bytes)401 int mtk_ecc_encode(struct mtk_ecc *ecc, struct mtk_ecc_config *config,
402 		   u8 *data, u32 bytes)
403 {
404 	dma_addr_t addr;
405 	u32 len;
406 	int ret;
407 
408 	addr = dma_map_single(ecc->dev, data, bytes, DMA_TO_DEVICE);
409 	ret = dma_mapping_error(ecc->dev, addr);
410 	if (ret) {
411 		dev_err(ecc->dev, "dma mapping error\n");
412 		return -EINVAL;
413 	}
414 
415 	config->op = ECC_ENCODE;
416 	config->addr = addr;
417 	ret = mtk_ecc_enable(ecc, config);
418 	if (ret) {
419 		dma_unmap_single(ecc->dev, addr, bytes, DMA_TO_DEVICE);
420 		return ret;
421 	}
422 
423 	ret = mtk_ecc_wait_done(ecc, ECC_ENCODE);
424 	if (ret)
425 		goto timeout;
426 
427 	ret = mtk_ecc_wait_idle(ecc, ECC_ENCODE);
428 	if (ret)
429 		goto timeout;
430 
431 	/* Program ECC bytes to OOB: per sector oob = FDM + ECC + SPARE */
432 	len = (config->strength * ecc->caps->parity_bits + 7) >> 3;
433 
434 	/* write the parity bytes generated by the ECC back to temp buffer */
435 	__ioread32_copy(ecc->eccdata,
436 			ecc->regs + ecc->caps->ecc_regs[ECC_ENCPAR00],
437 			round_up(len, 4));
438 
439 	/* copy into possibly unaligned OOB region with actual length */
440 	memcpy(data + bytes, ecc->eccdata, len);
441 timeout:
442 
443 	dma_unmap_single(ecc->dev, addr, bytes, DMA_TO_DEVICE);
444 	mtk_ecc_disable(ecc);
445 
446 	return ret;
447 }
448 EXPORT_SYMBOL(mtk_ecc_encode);
449 
mtk_ecc_adjust_strength(struct mtk_ecc * ecc,u32 * p)450 void mtk_ecc_adjust_strength(struct mtk_ecc *ecc, u32 *p)
451 {
452 	const u8 *ecc_strength = ecc->caps->ecc_strength;
453 	int i;
454 
455 	for (i = 0; i < ecc->caps->num_ecc_strength; i++) {
456 		if (*p <= ecc_strength[i]) {
457 			if (!i)
458 				*p = ecc_strength[i];
459 			else if (*p != ecc_strength[i])
460 				*p = ecc_strength[i - 1];
461 			return;
462 		}
463 	}
464 
465 	*p = ecc_strength[ecc->caps->num_ecc_strength - 1];
466 }
467 EXPORT_SYMBOL(mtk_ecc_adjust_strength);
468 
mtk_ecc_get_parity_bits(struct mtk_ecc * ecc)469 unsigned int mtk_ecc_get_parity_bits(struct mtk_ecc *ecc)
470 {
471 	return ecc->caps->parity_bits;
472 }
473 EXPORT_SYMBOL(mtk_ecc_get_parity_bits);
474 
475 static const struct mtk_ecc_caps mtk_ecc_caps_mt2701 = {
476 	.err_mask = ECC_ERRMASK_MT2701,
477 	.err_shift = 8,
478 	.ecc_strength = ecc_strength_mt2701,
479 	.ecc_regs = mt2701_ecc_regs,
480 	.num_ecc_strength = 20,
481 	.ecc_mode_shift = 5,
482 	.parity_bits = 14,
483 	.pg_irq_sel = 0,
484 };
485 
486 static const struct mtk_ecc_caps mtk_ecc_caps_mt2712 = {
487 	.err_mask = ECC_ERRMASK_MT2712,
488 	.err_shift = 8,
489 	.ecc_strength = ecc_strength_mt2712,
490 	.ecc_regs = mt2712_ecc_regs,
491 	.num_ecc_strength = 23,
492 	.ecc_mode_shift = 5,
493 	.parity_bits = 14,
494 	.pg_irq_sel = 1,
495 };
496 
497 static const struct mtk_ecc_caps mtk_ecc_caps_mt7622 = {
498 	.err_mask = ECC_ERRMASK_MT7622,
499 	.err_shift = 5,
500 	.ecc_strength = ecc_strength_mt7622,
501 	.ecc_regs = mt7622_ecc_regs,
502 	.num_ecc_strength = 5,
503 	.ecc_mode_shift = 4,
504 	.parity_bits = 13,
505 	.pg_irq_sel = 0,
506 };
507 
508 static const struct mtk_ecc_caps mtk_ecc_caps_mt7986 = {
509 	.err_mask = ECC_ERRMASK_MT7622,
510 	.err_shift = 8,
511 	.ecc_strength = ecc_strength_mt7986,
512 	.ecc_regs = mt2712_ecc_regs,
513 	.num_ecc_strength = 11,
514 	.ecc_mode_shift = 5,
515 	.parity_bits = 14,
516 	.pg_irq_sel = 1,
517 };
518 
519 static const struct of_device_id mtk_ecc_dt_match[] = {
520 	{
521 		.compatible = "mediatek,mt2701-ecc",
522 		.data = &mtk_ecc_caps_mt2701,
523 	}, {
524 		.compatible = "mediatek,mt2712-ecc",
525 		.data = &mtk_ecc_caps_mt2712,
526 	}, {
527 		.compatible = "mediatek,mt7622-ecc",
528 		.data = &mtk_ecc_caps_mt7622,
529 	}, {
530 		.compatible = "mediatek,mt7986-ecc",
531 		.data = &mtk_ecc_caps_mt7986,
532 	},
533 	{},
534 };
535 
mtk_ecc_probe(struct platform_device * pdev)536 static int mtk_ecc_probe(struct platform_device *pdev)
537 {
538 	struct device *dev = &pdev->dev;
539 	struct mtk_ecc *ecc;
540 	u32 max_eccdata_size;
541 	int irq, ret;
542 
543 	ecc = devm_kzalloc(dev, sizeof(*ecc), GFP_KERNEL);
544 	if (!ecc)
545 		return -ENOMEM;
546 
547 	ecc->caps = of_device_get_match_data(dev);
548 
549 	max_eccdata_size = ecc->caps->num_ecc_strength - 1;
550 	max_eccdata_size = ecc->caps->ecc_strength[max_eccdata_size];
551 	max_eccdata_size = (max_eccdata_size * ecc->caps->parity_bits + 7) >> 3;
552 	max_eccdata_size = round_up(max_eccdata_size, 4);
553 	ecc->eccdata = devm_kzalloc(dev, max_eccdata_size, GFP_KERNEL);
554 	if (!ecc->eccdata)
555 		return -ENOMEM;
556 
557 	ecc->regs = devm_platform_ioremap_resource(pdev, 0);
558 	if (IS_ERR(ecc->regs))
559 		return PTR_ERR(ecc->regs);
560 
561 	ecc->clk = devm_clk_get(dev, NULL);
562 	if (IS_ERR(ecc->clk)) {
563 		dev_err(dev, "failed to get clock: %ld\n", PTR_ERR(ecc->clk));
564 		return PTR_ERR(ecc->clk);
565 	}
566 
567 	irq = platform_get_irq(pdev, 0);
568 	if (irq < 0)
569 		return irq;
570 
571 	ret = dma_set_mask(dev, DMA_BIT_MASK(32));
572 	if (ret) {
573 		dev_err(dev, "failed to set DMA mask\n");
574 		return ret;
575 	}
576 
577 	ret = devm_request_irq(dev, irq, mtk_ecc_irq, 0x0, "mtk-ecc", ecc);
578 	if (ret) {
579 		dev_err(dev, "failed to request irq\n");
580 		return -EINVAL;
581 	}
582 
583 	ecc->dev = dev;
584 	mutex_init(&ecc->lock);
585 	platform_set_drvdata(pdev, ecc);
586 	dev_info(dev, "probed\n");
587 
588 	return 0;
589 }
590 
591 #ifdef CONFIG_PM_SLEEP
mtk_ecc_suspend(struct device * dev)592 static int mtk_ecc_suspend(struct device *dev)
593 {
594 	struct mtk_ecc *ecc = dev_get_drvdata(dev);
595 
596 	clk_disable_unprepare(ecc->clk);
597 
598 	return 0;
599 }
600 
mtk_ecc_resume(struct device * dev)601 static int mtk_ecc_resume(struct device *dev)
602 {
603 	struct mtk_ecc *ecc = dev_get_drvdata(dev);
604 	int ret;
605 
606 	ret = clk_prepare_enable(ecc->clk);
607 	if (ret) {
608 		dev_err(dev, "failed to enable clk\n");
609 		return ret;
610 	}
611 
612 	return 0;
613 }
614 
615 static SIMPLE_DEV_PM_OPS(mtk_ecc_pm_ops, mtk_ecc_suspend, mtk_ecc_resume);
616 #endif
617 
618 MODULE_DEVICE_TABLE(of, mtk_ecc_dt_match);
619 
620 static struct platform_driver mtk_ecc_driver = {
621 	.probe  = mtk_ecc_probe,
622 	.driver = {
623 		.name  = "mtk-ecc",
624 		.of_match_table = mtk_ecc_dt_match,
625 #ifdef CONFIG_PM_SLEEP
626 		.pm = &mtk_ecc_pm_ops,
627 #endif
628 	},
629 };
630 
631 module_platform_driver(mtk_ecc_driver);
632 
633 MODULE_AUTHOR("Xiaolei Li <xiaolei.li@mediatek.com>");
634 MODULE_DESCRIPTION("MTK Nand ECC Driver");
635 MODULE_LICENSE("Dual MIT/GPL");
636