xref: /linux/drivers/mtd/nand/raw/stm32_fmc2_nand.c (revision 78c3925c048c752334873f56c3a3d1c9d53e0416)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) STMicroelectronics 2018
4  * Author: Christophe Kerello <christophe.kerello@st.com>
5  */
6 
7 #include <linux/bitfield.h>
8 #include <linux/clk.h>
9 #include <linux/dmaengine.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/errno.h>
12 #include <linux/gpio/consumer.h>
13 #include <linux/interrupt.h>
14 #include <linux/iopoll.h>
15 #include <linux/mfd/syscon.h>
16 #include <linux/module.h>
17 #include <linux/mtd/rawnand.h>
18 #include <linux/of_address.h>
19 #include <linux/of_device.h>
20 #include <linux/pinctrl/consumer.h>
21 #include <linux/platform_device.h>
22 #include <linux/regmap.h>
23 #include <linux/reset.h>
24 
25 /* Bad block marker length */
26 #define FMC2_BBM_LEN			2
27 
28 /* ECC step size */
29 #define FMC2_ECC_STEP_SIZE		512
30 
31 /* BCHDSRx registers length */
32 #define FMC2_BCHDSRS_LEN		20
33 
34 /* HECCR length */
35 #define FMC2_HECCR_LEN			4
36 
37 /* Max requests done for a 8k nand page size */
38 #define FMC2_MAX_SG			16
39 
40 /* Max chip enable */
41 #define FMC2_MAX_CE			4
42 
43 /* Max ECC buffer length */
44 #define FMC2_MAX_ECC_BUF_LEN		(FMC2_BCHDSRS_LEN * FMC2_MAX_SG)
45 
46 #define FMC2_TIMEOUT_MS			5000
47 
48 /* Timings */
49 #define FMC2_THIZ			1
50 #define FMC2_TIO			8000
51 #define FMC2_TSYNC			3000
52 #define FMC2_PCR_TIMING_MASK		0xf
53 #define FMC2_PMEM_PATT_TIMING_MASK	0xff
54 
55 /* FMC2 Controller Registers */
56 #define FMC2_BCR1			0x0
57 #define FMC2_PCR			0x80
58 #define FMC2_SR				0x84
59 #define FMC2_PMEM			0x88
60 #define FMC2_PATT			0x8c
61 #define FMC2_HECCR			0x94
62 #define FMC2_ISR			0x184
63 #define FMC2_ICR			0x188
64 #define FMC2_CSQCR			0x200
65 #define FMC2_CSQCFGR1			0x204
66 #define FMC2_CSQCFGR2			0x208
67 #define FMC2_CSQCFGR3			0x20c
68 #define FMC2_CSQAR1			0x210
69 #define FMC2_CSQAR2			0x214
70 #define FMC2_CSQIER			0x220
71 #define FMC2_CSQISR			0x224
72 #define FMC2_CSQICR			0x228
73 #define FMC2_CSQEMSR			0x230
74 #define FMC2_BCHIER			0x250
75 #define FMC2_BCHISR			0x254
76 #define FMC2_BCHICR			0x258
77 #define FMC2_BCHPBR1			0x260
78 #define FMC2_BCHPBR2			0x264
79 #define FMC2_BCHPBR3			0x268
80 #define FMC2_BCHPBR4			0x26c
81 #define FMC2_BCHDSR0			0x27c
82 #define FMC2_BCHDSR1			0x280
83 #define FMC2_BCHDSR2			0x284
84 #define FMC2_BCHDSR3			0x288
85 #define FMC2_BCHDSR4			0x28c
86 
87 /* Register: FMC2_BCR1 */
88 #define FMC2_BCR1_FMC2EN		BIT(31)
89 
90 /* Register: FMC2_PCR */
91 #define FMC2_PCR_PWAITEN		BIT(1)
92 #define FMC2_PCR_PBKEN			BIT(2)
93 #define FMC2_PCR_PWID			GENMASK(5, 4)
94 #define FMC2_PCR_PWID_BUSWIDTH_8	0
95 #define FMC2_PCR_PWID_BUSWIDTH_16	1
96 #define FMC2_PCR_ECCEN			BIT(6)
97 #define FMC2_PCR_ECCALG			BIT(8)
98 #define FMC2_PCR_TCLR			GENMASK(12, 9)
99 #define FMC2_PCR_TCLR_DEFAULT		0xf
100 #define FMC2_PCR_TAR			GENMASK(16, 13)
101 #define FMC2_PCR_TAR_DEFAULT		0xf
102 #define FMC2_PCR_ECCSS			GENMASK(19, 17)
103 #define FMC2_PCR_ECCSS_512		1
104 #define FMC2_PCR_ECCSS_2048		3
105 #define FMC2_PCR_BCHECC			BIT(24)
106 #define FMC2_PCR_WEN			BIT(25)
107 
108 /* Register: FMC2_SR */
109 #define FMC2_SR_NWRF			BIT(6)
110 
111 /* Register: FMC2_PMEM */
112 #define FMC2_PMEM_MEMSET		GENMASK(7, 0)
113 #define FMC2_PMEM_MEMWAIT		GENMASK(15, 8)
114 #define FMC2_PMEM_MEMHOLD		GENMASK(23, 16)
115 #define FMC2_PMEM_MEMHIZ		GENMASK(31, 24)
116 #define FMC2_PMEM_DEFAULT		0x0a0a0a0a
117 
118 /* Register: FMC2_PATT */
119 #define FMC2_PATT_ATTSET		GENMASK(7, 0)
120 #define FMC2_PATT_ATTWAIT		GENMASK(15, 8)
121 #define FMC2_PATT_ATTHOLD		GENMASK(23, 16)
122 #define FMC2_PATT_ATTHIZ		GENMASK(31, 24)
123 #define FMC2_PATT_DEFAULT		0x0a0a0a0a
124 
125 /* Register: FMC2_ISR */
126 #define FMC2_ISR_IHLF			BIT(1)
127 
128 /* Register: FMC2_ICR */
129 #define FMC2_ICR_CIHLF			BIT(1)
130 
131 /* Register: FMC2_CSQCR */
132 #define FMC2_CSQCR_CSQSTART		BIT(0)
133 
134 /* Register: FMC2_CSQCFGR1 */
135 #define FMC2_CSQCFGR1_CMD2EN		BIT(1)
136 #define FMC2_CSQCFGR1_DMADEN		BIT(2)
137 #define FMC2_CSQCFGR1_ACYNBR		GENMASK(6, 4)
138 #define FMC2_CSQCFGR1_CMD1		GENMASK(15, 8)
139 #define FMC2_CSQCFGR1_CMD2		GENMASK(23, 16)
140 #define FMC2_CSQCFGR1_CMD1T		BIT(24)
141 #define FMC2_CSQCFGR1_CMD2T		BIT(25)
142 
143 /* Register: FMC2_CSQCFGR2 */
144 #define FMC2_CSQCFGR2_SQSDTEN		BIT(0)
145 #define FMC2_CSQCFGR2_RCMD2EN		BIT(1)
146 #define FMC2_CSQCFGR2_DMASEN		BIT(2)
147 #define FMC2_CSQCFGR2_RCMD1		GENMASK(15, 8)
148 #define FMC2_CSQCFGR2_RCMD2		GENMASK(23, 16)
149 #define FMC2_CSQCFGR2_RCMD1T		BIT(24)
150 #define FMC2_CSQCFGR2_RCMD2T		BIT(25)
151 
152 /* Register: FMC2_CSQCFGR3 */
153 #define FMC2_CSQCFGR3_SNBR		GENMASK(13, 8)
154 #define FMC2_CSQCFGR3_AC1T		BIT(16)
155 #define FMC2_CSQCFGR3_AC2T		BIT(17)
156 #define FMC2_CSQCFGR3_AC3T		BIT(18)
157 #define FMC2_CSQCFGR3_AC4T		BIT(19)
158 #define FMC2_CSQCFGR3_AC5T		BIT(20)
159 #define FMC2_CSQCFGR3_SDT		BIT(21)
160 #define FMC2_CSQCFGR3_RAC1T		BIT(22)
161 #define FMC2_CSQCFGR3_RAC2T		BIT(23)
162 
163 /* Register: FMC2_CSQCAR1 */
164 #define FMC2_CSQCAR1_ADDC1		GENMASK(7, 0)
165 #define FMC2_CSQCAR1_ADDC2		GENMASK(15, 8)
166 #define FMC2_CSQCAR1_ADDC3		GENMASK(23, 16)
167 #define FMC2_CSQCAR1_ADDC4		GENMASK(31, 24)
168 
169 /* Register: FMC2_CSQCAR2 */
170 #define FMC2_CSQCAR2_ADDC5		GENMASK(7, 0)
171 #define FMC2_CSQCAR2_NANDCEN		GENMASK(11, 10)
172 #define FMC2_CSQCAR2_SAO		GENMASK(31, 16)
173 
174 /* Register: FMC2_CSQIER */
175 #define FMC2_CSQIER_TCIE		BIT(0)
176 
177 /* Register: FMC2_CSQICR */
178 #define FMC2_CSQICR_CLEAR_IRQ		GENMASK(4, 0)
179 
180 /* Register: FMC2_CSQEMSR */
181 #define FMC2_CSQEMSR_SEM		GENMASK(15, 0)
182 
183 /* Register: FMC2_BCHIER */
184 #define FMC2_BCHIER_DERIE		BIT(1)
185 #define FMC2_BCHIER_EPBRIE		BIT(4)
186 
187 /* Register: FMC2_BCHICR */
188 #define FMC2_BCHICR_CLEAR_IRQ		GENMASK(4, 0)
189 
190 /* Register: FMC2_BCHDSR0 */
191 #define FMC2_BCHDSR0_DUE		BIT(0)
192 #define FMC2_BCHDSR0_DEF		BIT(1)
193 #define FMC2_BCHDSR0_DEN		GENMASK(7, 4)
194 
195 /* Register: FMC2_BCHDSR1 */
196 #define FMC2_BCHDSR1_EBP1		GENMASK(12, 0)
197 #define FMC2_BCHDSR1_EBP2		GENMASK(28, 16)
198 
199 /* Register: FMC2_BCHDSR2 */
200 #define FMC2_BCHDSR2_EBP3		GENMASK(12, 0)
201 #define FMC2_BCHDSR2_EBP4		GENMASK(28, 16)
202 
203 /* Register: FMC2_BCHDSR3 */
204 #define FMC2_BCHDSR3_EBP5		GENMASK(12, 0)
205 #define FMC2_BCHDSR3_EBP6		GENMASK(28, 16)
206 
207 /* Register: FMC2_BCHDSR4 */
208 #define FMC2_BCHDSR4_EBP7		GENMASK(12, 0)
209 #define FMC2_BCHDSR4_EBP8		GENMASK(28, 16)
210 
211 enum stm32_fmc2_ecc {
212 	FMC2_ECC_HAM = 1,
213 	FMC2_ECC_BCH4 = 4,
214 	FMC2_ECC_BCH8 = 8
215 };
216 
217 enum stm32_fmc2_irq_state {
218 	FMC2_IRQ_UNKNOWN = 0,
219 	FMC2_IRQ_BCH,
220 	FMC2_IRQ_SEQ
221 };
222 
223 struct stm32_fmc2_timings {
224 	u8 tclr;
225 	u8 tar;
226 	u8 thiz;
227 	u8 twait;
228 	u8 thold_mem;
229 	u8 tset_mem;
230 	u8 thold_att;
231 	u8 tset_att;
232 };
233 
234 struct stm32_fmc2_nand {
235 	struct nand_chip chip;
236 	struct gpio_desc *wp_gpio;
237 	struct stm32_fmc2_timings timings;
238 	int ncs;
239 	int cs_used[FMC2_MAX_CE];
240 };
241 
242 static inline struct stm32_fmc2_nand *to_fmc2_nand(struct nand_chip *chip)
243 {
244 	return container_of(chip, struct stm32_fmc2_nand, chip);
245 }
246 
247 struct stm32_fmc2_nfc;
248 
249 struct stm32_fmc2_nfc_data {
250 	int max_ncs;
251 	int (*set_cdev)(struct stm32_fmc2_nfc *nfc);
252 };
253 
254 struct stm32_fmc2_nfc {
255 	struct nand_controller base;
256 	struct stm32_fmc2_nand nand;
257 	struct device *dev;
258 	struct device *cdev;
259 	struct regmap *regmap;
260 	void __iomem *data_base[FMC2_MAX_CE];
261 	void __iomem *cmd_base[FMC2_MAX_CE];
262 	void __iomem *addr_base[FMC2_MAX_CE];
263 	phys_addr_t io_phys_addr;
264 	phys_addr_t data_phys_addr[FMC2_MAX_CE];
265 	struct clk *clk;
266 	u8 irq_state;
267 	const struct stm32_fmc2_nfc_data *data;
268 
269 	struct dma_chan *dma_tx_ch;
270 	struct dma_chan *dma_rx_ch;
271 	struct dma_chan *dma_ecc_ch;
272 	struct sg_table dma_data_sg;
273 	struct sg_table dma_ecc_sg;
274 	u8 *ecc_buf;
275 	int dma_ecc_len;
276 	u32 tx_dma_max_burst;
277 	u32 rx_dma_max_burst;
278 
279 	struct completion complete;
280 	struct completion dma_data_complete;
281 	struct completion dma_ecc_complete;
282 
283 	u8 cs_assigned;
284 	int cs_sel;
285 };
286 
287 static inline struct stm32_fmc2_nfc *to_stm32_nfc(struct nand_controller *base)
288 {
289 	return container_of(base, struct stm32_fmc2_nfc, base);
290 }
291 
292 static void stm32_fmc2_nfc_timings_init(struct nand_chip *chip)
293 {
294 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
295 	struct stm32_fmc2_nand *nand = to_fmc2_nand(chip);
296 	struct stm32_fmc2_timings *timings = &nand->timings;
297 	u32 pmem, patt;
298 
299 	/* Set tclr/tar timings */
300 	regmap_update_bits(nfc->regmap, FMC2_PCR,
301 			   FMC2_PCR_TCLR | FMC2_PCR_TAR,
302 			   FIELD_PREP(FMC2_PCR_TCLR, timings->tclr) |
303 			   FIELD_PREP(FMC2_PCR_TAR, timings->tar));
304 
305 	/* Set tset/twait/thold/thiz timings in common bank */
306 	pmem = FIELD_PREP(FMC2_PMEM_MEMSET, timings->tset_mem);
307 	pmem |= FIELD_PREP(FMC2_PMEM_MEMWAIT, timings->twait);
308 	pmem |= FIELD_PREP(FMC2_PMEM_MEMHOLD, timings->thold_mem);
309 	pmem |= FIELD_PREP(FMC2_PMEM_MEMHIZ, timings->thiz);
310 	regmap_write(nfc->regmap, FMC2_PMEM, pmem);
311 
312 	/* Set tset/twait/thold/thiz timings in attribut bank */
313 	patt = FIELD_PREP(FMC2_PATT_ATTSET, timings->tset_att);
314 	patt |= FIELD_PREP(FMC2_PATT_ATTWAIT, timings->twait);
315 	patt |= FIELD_PREP(FMC2_PATT_ATTHOLD, timings->thold_att);
316 	patt |= FIELD_PREP(FMC2_PATT_ATTHIZ, timings->thiz);
317 	regmap_write(nfc->regmap, FMC2_PATT, patt);
318 }
319 
320 static void stm32_fmc2_nfc_setup(struct nand_chip *chip)
321 {
322 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
323 	u32 pcr = 0, pcr_mask;
324 
325 	/* Configure ECC algorithm (default configuration is Hamming) */
326 	pcr_mask = FMC2_PCR_ECCALG;
327 	pcr_mask |= FMC2_PCR_BCHECC;
328 	if (chip->ecc.strength == FMC2_ECC_BCH8) {
329 		pcr |= FMC2_PCR_ECCALG;
330 		pcr |= FMC2_PCR_BCHECC;
331 	} else if (chip->ecc.strength == FMC2_ECC_BCH4) {
332 		pcr |= FMC2_PCR_ECCALG;
333 	}
334 
335 	/* Set buswidth */
336 	pcr_mask |= FMC2_PCR_PWID;
337 	if (chip->options & NAND_BUSWIDTH_16)
338 		pcr |= FIELD_PREP(FMC2_PCR_PWID, FMC2_PCR_PWID_BUSWIDTH_16);
339 
340 	/* Set ECC sector size */
341 	pcr_mask |= FMC2_PCR_ECCSS;
342 	pcr |= FIELD_PREP(FMC2_PCR_ECCSS, FMC2_PCR_ECCSS_512);
343 
344 	regmap_update_bits(nfc->regmap, FMC2_PCR, pcr_mask, pcr);
345 }
346 
347 static int stm32_fmc2_nfc_select_chip(struct nand_chip *chip, int chipnr)
348 {
349 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
350 	struct stm32_fmc2_nand *nand = to_fmc2_nand(chip);
351 	struct dma_slave_config dma_cfg;
352 	int ret;
353 
354 	if (nand->cs_used[chipnr] == nfc->cs_sel)
355 		return 0;
356 
357 	nfc->cs_sel = nand->cs_used[chipnr];
358 	stm32_fmc2_nfc_setup(chip);
359 	stm32_fmc2_nfc_timings_init(chip);
360 
361 	if (nfc->dma_tx_ch) {
362 		memset(&dma_cfg, 0, sizeof(dma_cfg));
363 		dma_cfg.dst_addr = nfc->data_phys_addr[nfc->cs_sel];
364 		dma_cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
365 		dma_cfg.dst_maxburst = nfc->tx_dma_max_burst /
366 				       dma_cfg.dst_addr_width;
367 
368 		ret = dmaengine_slave_config(nfc->dma_tx_ch, &dma_cfg);
369 		if (ret) {
370 			dev_err(nfc->dev, "tx DMA engine slave config failed\n");
371 			return ret;
372 		}
373 	}
374 
375 	if (nfc->dma_rx_ch) {
376 		memset(&dma_cfg, 0, sizeof(dma_cfg));
377 		dma_cfg.src_addr = nfc->data_phys_addr[nfc->cs_sel];
378 		dma_cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
379 		dma_cfg.src_maxburst = nfc->rx_dma_max_burst /
380 				       dma_cfg.src_addr_width;
381 
382 		ret = dmaengine_slave_config(nfc->dma_rx_ch, &dma_cfg);
383 		if (ret) {
384 			dev_err(nfc->dev, "rx DMA engine slave config failed\n");
385 			return ret;
386 		}
387 	}
388 
389 	if (nfc->dma_ecc_ch) {
390 		/*
391 		 * Hamming: we read HECCR register
392 		 * BCH4/BCH8: we read BCHDSRSx registers
393 		 */
394 		memset(&dma_cfg, 0, sizeof(dma_cfg));
395 		dma_cfg.src_addr = nfc->io_phys_addr;
396 		dma_cfg.src_addr += chip->ecc.strength == FMC2_ECC_HAM ?
397 				    FMC2_HECCR : FMC2_BCHDSR0;
398 		dma_cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
399 
400 		ret = dmaengine_slave_config(nfc->dma_ecc_ch, &dma_cfg);
401 		if (ret) {
402 			dev_err(nfc->dev, "ECC DMA engine slave config failed\n");
403 			return ret;
404 		}
405 
406 		/* Calculate ECC length needed for one sector */
407 		nfc->dma_ecc_len = chip->ecc.strength == FMC2_ECC_HAM ?
408 				   FMC2_HECCR_LEN : FMC2_BCHDSRS_LEN;
409 	}
410 
411 	return 0;
412 }
413 
414 static void stm32_fmc2_nfc_set_buswidth_16(struct stm32_fmc2_nfc *nfc, bool set)
415 {
416 	u32 pcr;
417 
418 	pcr = set ? FIELD_PREP(FMC2_PCR_PWID, FMC2_PCR_PWID_BUSWIDTH_16) :
419 		    FIELD_PREP(FMC2_PCR_PWID, FMC2_PCR_PWID_BUSWIDTH_8);
420 
421 	regmap_update_bits(nfc->regmap, FMC2_PCR, FMC2_PCR_PWID, pcr);
422 }
423 
424 static void stm32_fmc2_nfc_set_ecc(struct stm32_fmc2_nfc *nfc, bool enable)
425 {
426 	regmap_update_bits(nfc->regmap, FMC2_PCR, FMC2_PCR_ECCEN,
427 			   enable ? FMC2_PCR_ECCEN : 0);
428 }
429 
430 static void stm32_fmc2_nfc_enable_seq_irq(struct stm32_fmc2_nfc *nfc)
431 {
432 	nfc->irq_state = FMC2_IRQ_SEQ;
433 
434 	regmap_update_bits(nfc->regmap, FMC2_CSQIER,
435 			   FMC2_CSQIER_TCIE, FMC2_CSQIER_TCIE);
436 }
437 
438 static void stm32_fmc2_nfc_disable_seq_irq(struct stm32_fmc2_nfc *nfc)
439 {
440 	regmap_update_bits(nfc->regmap, FMC2_CSQIER, FMC2_CSQIER_TCIE, 0);
441 
442 	nfc->irq_state = FMC2_IRQ_UNKNOWN;
443 }
444 
445 static void stm32_fmc2_nfc_clear_seq_irq(struct stm32_fmc2_nfc *nfc)
446 {
447 	regmap_write(nfc->regmap, FMC2_CSQICR, FMC2_CSQICR_CLEAR_IRQ);
448 }
449 
450 static void stm32_fmc2_nfc_enable_bch_irq(struct stm32_fmc2_nfc *nfc, int mode)
451 {
452 	nfc->irq_state = FMC2_IRQ_BCH;
453 
454 	if (mode == NAND_ECC_WRITE)
455 		regmap_update_bits(nfc->regmap, FMC2_BCHIER,
456 				   FMC2_BCHIER_EPBRIE, FMC2_BCHIER_EPBRIE);
457 	else
458 		regmap_update_bits(nfc->regmap, FMC2_BCHIER,
459 				   FMC2_BCHIER_DERIE, FMC2_BCHIER_DERIE);
460 }
461 
462 static void stm32_fmc2_nfc_disable_bch_irq(struct stm32_fmc2_nfc *nfc)
463 {
464 	regmap_update_bits(nfc->regmap, FMC2_BCHIER,
465 			   FMC2_BCHIER_DERIE | FMC2_BCHIER_EPBRIE, 0);
466 
467 	nfc->irq_state = FMC2_IRQ_UNKNOWN;
468 }
469 
470 static void stm32_fmc2_nfc_clear_bch_irq(struct stm32_fmc2_nfc *nfc)
471 {
472 	regmap_write(nfc->regmap, FMC2_BCHICR, FMC2_BCHICR_CLEAR_IRQ);
473 }
474 
475 /*
476  * Enable ECC logic and reset syndrome/parity bits previously calculated
477  * Syndrome/parity bits is cleared by setting the ECCEN bit to 0
478  */
479 static void stm32_fmc2_nfc_hwctl(struct nand_chip *chip, int mode)
480 {
481 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
482 
483 	stm32_fmc2_nfc_set_ecc(nfc, false);
484 
485 	if (chip->ecc.strength != FMC2_ECC_HAM) {
486 		regmap_update_bits(nfc->regmap, FMC2_PCR, FMC2_PCR_WEN,
487 				   mode == NAND_ECC_WRITE ? FMC2_PCR_WEN : 0);
488 
489 		reinit_completion(&nfc->complete);
490 		stm32_fmc2_nfc_clear_bch_irq(nfc);
491 		stm32_fmc2_nfc_enable_bch_irq(nfc, mode);
492 	}
493 
494 	stm32_fmc2_nfc_set_ecc(nfc, true);
495 }
496 
497 /*
498  * ECC Hamming calculation
499  * ECC is 3 bytes for 512 bytes of data (supports error correction up to
500  * max of 1-bit)
501  */
502 static void stm32_fmc2_nfc_ham_set_ecc(const u32 ecc_sta, u8 *ecc)
503 {
504 	ecc[0] = ecc_sta;
505 	ecc[1] = ecc_sta >> 8;
506 	ecc[2] = ecc_sta >> 16;
507 }
508 
509 static int stm32_fmc2_nfc_ham_calculate(struct nand_chip *chip, const u8 *data,
510 					u8 *ecc)
511 {
512 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
513 	u32 sr, heccr;
514 	int ret;
515 
516 	ret = regmap_read_poll_timeout(nfc->regmap, FMC2_SR, sr,
517 				       sr & FMC2_SR_NWRF, 1,
518 				       1000 * FMC2_TIMEOUT_MS);
519 	if (ret) {
520 		dev_err(nfc->dev, "ham timeout\n");
521 		return ret;
522 	}
523 
524 	regmap_read(nfc->regmap, FMC2_HECCR, &heccr);
525 	stm32_fmc2_nfc_ham_set_ecc(heccr, ecc);
526 	stm32_fmc2_nfc_set_ecc(nfc, false);
527 
528 	return 0;
529 }
530 
531 static int stm32_fmc2_nfc_ham_correct(struct nand_chip *chip, u8 *dat,
532 				      u8 *read_ecc, u8 *calc_ecc)
533 {
534 	u8 bit_position = 0, b0, b1, b2;
535 	u32 byte_addr = 0, b;
536 	u32 i, shifting = 1;
537 
538 	/* Indicate which bit and byte is faulty (if any) */
539 	b0 = read_ecc[0] ^ calc_ecc[0];
540 	b1 = read_ecc[1] ^ calc_ecc[1];
541 	b2 = read_ecc[2] ^ calc_ecc[2];
542 	b = b0 | (b1 << 8) | (b2 << 16);
543 
544 	/* No errors */
545 	if (likely(!b))
546 		return 0;
547 
548 	/* Calculate bit position */
549 	for (i = 0; i < 3; i++) {
550 		switch (b % 4) {
551 		case 2:
552 			bit_position += shifting;
553 			break;
554 		case 1:
555 			break;
556 		default:
557 			return -EBADMSG;
558 		}
559 		shifting <<= 1;
560 		b >>= 2;
561 	}
562 
563 	/* Calculate byte position */
564 	shifting = 1;
565 	for (i = 0; i < 9; i++) {
566 		switch (b % 4) {
567 		case 2:
568 			byte_addr += shifting;
569 			break;
570 		case 1:
571 			break;
572 		default:
573 			return -EBADMSG;
574 		}
575 		shifting <<= 1;
576 		b >>= 2;
577 	}
578 
579 	/* Flip the bit */
580 	dat[byte_addr] ^= (1 << bit_position);
581 
582 	return 1;
583 }
584 
585 /*
586  * ECC BCH calculation and correction
587  * ECC is 7/13 bytes for 512 bytes of data (supports error correction up to
588  * max of 4-bit/8-bit)
589  */
590 static int stm32_fmc2_nfc_bch_calculate(struct nand_chip *chip, const u8 *data,
591 					u8 *ecc)
592 {
593 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
594 	u32 bchpbr;
595 
596 	/* Wait until the BCH code is ready */
597 	if (!wait_for_completion_timeout(&nfc->complete,
598 					 msecs_to_jiffies(FMC2_TIMEOUT_MS))) {
599 		dev_err(nfc->dev, "bch timeout\n");
600 		stm32_fmc2_nfc_disable_bch_irq(nfc);
601 		return -ETIMEDOUT;
602 	}
603 
604 	/* Read parity bits */
605 	regmap_read(nfc->regmap, FMC2_BCHPBR1, &bchpbr);
606 	ecc[0] = bchpbr;
607 	ecc[1] = bchpbr >> 8;
608 	ecc[2] = bchpbr >> 16;
609 	ecc[3] = bchpbr >> 24;
610 
611 	regmap_read(nfc->regmap, FMC2_BCHPBR2, &bchpbr);
612 	ecc[4] = bchpbr;
613 	ecc[5] = bchpbr >> 8;
614 	ecc[6] = bchpbr >> 16;
615 
616 	if (chip->ecc.strength == FMC2_ECC_BCH8) {
617 		ecc[7] = bchpbr >> 24;
618 
619 		regmap_read(nfc->regmap, FMC2_BCHPBR3, &bchpbr);
620 		ecc[8] = bchpbr;
621 		ecc[9] = bchpbr >> 8;
622 		ecc[10] = bchpbr >> 16;
623 		ecc[11] = bchpbr >> 24;
624 
625 		regmap_read(nfc->regmap, FMC2_BCHPBR4, &bchpbr);
626 		ecc[12] = bchpbr;
627 	}
628 
629 	stm32_fmc2_nfc_set_ecc(nfc, false);
630 
631 	return 0;
632 }
633 
634 static int stm32_fmc2_nfc_bch_decode(int eccsize, u8 *dat, u32 *ecc_sta)
635 {
636 	u32 bchdsr0 = ecc_sta[0];
637 	u32 bchdsr1 = ecc_sta[1];
638 	u32 bchdsr2 = ecc_sta[2];
639 	u32 bchdsr3 = ecc_sta[3];
640 	u32 bchdsr4 = ecc_sta[4];
641 	u16 pos[8];
642 	int i, den;
643 	unsigned int nb_errs = 0;
644 
645 	/* No errors found */
646 	if (likely(!(bchdsr0 & FMC2_BCHDSR0_DEF)))
647 		return 0;
648 
649 	/* Too many errors detected */
650 	if (unlikely(bchdsr0 & FMC2_BCHDSR0_DUE))
651 		return -EBADMSG;
652 
653 	pos[0] = FIELD_GET(FMC2_BCHDSR1_EBP1, bchdsr1);
654 	pos[1] = FIELD_GET(FMC2_BCHDSR1_EBP2, bchdsr1);
655 	pos[2] = FIELD_GET(FMC2_BCHDSR2_EBP3, bchdsr2);
656 	pos[3] = FIELD_GET(FMC2_BCHDSR2_EBP4, bchdsr2);
657 	pos[4] = FIELD_GET(FMC2_BCHDSR3_EBP5, bchdsr3);
658 	pos[5] = FIELD_GET(FMC2_BCHDSR3_EBP6, bchdsr3);
659 	pos[6] = FIELD_GET(FMC2_BCHDSR4_EBP7, bchdsr4);
660 	pos[7] = FIELD_GET(FMC2_BCHDSR4_EBP8, bchdsr4);
661 
662 	den = FIELD_GET(FMC2_BCHDSR0_DEN, bchdsr0);
663 	for (i = 0; i < den; i++) {
664 		if (pos[i] < eccsize * 8) {
665 			change_bit(pos[i], (unsigned long *)dat);
666 			nb_errs++;
667 		}
668 	}
669 
670 	return nb_errs;
671 }
672 
673 static int stm32_fmc2_nfc_bch_correct(struct nand_chip *chip, u8 *dat,
674 				      u8 *read_ecc, u8 *calc_ecc)
675 {
676 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
677 	u32 ecc_sta[5];
678 
679 	/* Wait until the decoding error is ready */
680 	if (!wait_for_completion_timeout(&nfc->complete,
681 					 msecs_to_jiffies(FMC2_TIMEOUT_MS))) {
682 		dev_err(nfc->dev, "bch timeout\n");
683 		stm32_fmc2_nfc_disable_bch_irq(nfc);
684 		return -ETIMEDOUT;
685 	}
686 
687 	regmap_bulk_read(nfc->regmap, FMC2_BCHDSR0, ecc_sta, 5);
688 
689 	stm32_fmc2_nfc_set_ecc(nfc, false);
690 
691 	return stm32_fmc2_nfc_bch_decode(chip->ecc.size, dat, ecc_sta);
692 }
693 
694 static int stm32_fmc2_nfc_read_page(struct nand_chip *chip, u8 *buf,
695 				    int oob_required, int page)
696 {
697 	struct mtd_info *mtd = nand_to_mtd(chip);
698 	int ret, i, s, stat, eccsize = chip->ecc.size;
699 	int eccbytes = chip->ecc.bytes;
700 	int eccsteps = chip->ecc.steps;
701 	int eccstrength = chip->ecc.strength;
702 	u8 *p = buf;
703 	u8 *ecc_calc = chip->ecc.calc_buf;
704 	u8 *ecc_code = chip->ecc.code_buf;
705 	unsigned int max_bitflips = 0;
706 
707 	ret = nand_read_page_op(chip, page, 0, NULL, 0);
708 	if (ret)
709 		return ret;
710 
711 	for (i = mtd->writesize + FMC2_BBM_LEN, s = 0; s < eccsteps;
712 	     s++, i += eccbytes, p += eccsize) {
713 		chip->ecc.hwctl(chip, NAND_ECC_READ);
714 
715 		/* Read the nand page sector (512 bytes) */
716 		ret = nand_change_read_column_op(chip, s * eccsize, p,
717 						 eccsize, false);
718 		if (ret)
719 			return ret;
720 
721 		/* Read the corresponding ECC bytes */
722 		ret = nand_change_read_column_op(chip, i, ecc_code,
723 						 eccbytes, false);
724 		if (ret)
725 			return ret;
726 
727 		/* Correct the data */
728 		stat = chip->ecc.correct(chip, p, ecc_code, ecc_calc);
729 		if (stat == -EBADMSG)
730 			/* Check for empty pages with bitflips */
731 			stat = nand_check_erased_ecc_chunk(p, eccsize,
732 							   ecc_code, eccbytes,
733 							   NULL, 0,
734 							   eccstrength);
735 
736 		if (stat < 0) {
737 			mtd->ecc_stats.failed++;
738 		} else {
739 			mtd->ecc_stats.corrected += stat;
740 			max_bitflips = max_t(unsigned int, max_bitflips, stat);
741 		}
742 	}
743 
744 	/* Read oob */
745 	if (oob_required) {
746 		ret = nand_change_read_column_op(chip, mtd->writesize,
747 						 chip->oob_poi, mtd->oobsize,
748 						 false);
749 		if (ret)
750 			return ret;
751 	}
752 
753 	return max_bitflips;
754 }
755 
756 /* Sequencer read/write configuration */
757 static void stm32_fmc2_nfc_rw_page_init(struct nand_chip *chip, int page,
758 					int raw, bool write_data)
759 {
760 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
761 	struct mtd_info *mtd = nand_to_mtd(chip);
762 	u32 ecc_offset = mtd->writesize + FMC2_BBM_LEN;
763 	/*
764 	 * cfg[0] => csqcfgr1, cfg[1] => csqcfgr2, cfg[2] => csqcfgr3
765 	 * cfg[3] => csqar1, cfg[4] => csqar2
766 	 */
767 	u32 cfg[5];
768 
769 	regmap_update_bits(nfc->regmap, FMC2_PCR, FMC2_PCR_WEN,
770 			   write_data ? FMC2_PCR_WEN : 0);
771 
772 	/*
773 	 * - Set Program Page/Page Read command
774 	 * - Enable DMA request data
775 	 * - Set timings
776 	 */
777 	cfg[0] = FMC2_CSQCFGR1_DMADEN | FMC2_CSQCFGR1_CMD1T;
778 	if (write_data)
779 		cfg[0] |= FIELD_PREP(FMC2_CSQCFGR1_CMD1, NAND_CMD_SEQIN);
780 	else
781 		cfg[0] |= FIELD_PREP(FMC2_CSQCFGR1_CMD1, NAND_CMD_READ0) |
782 			  FMC2_CSQCFGR1_CMD2EN |
783 			  FIELD_PREP(FMC2_CSQCFGR1_CMD2, NAND_CMD_READSTART) |
784 			  FMC2_CSQCFGR1_CMD2T;
785 
786 	/*
787 	 * - Set Random Data Input/Random Data Read command
788 	 * - Enable the sequencer to access the Spare data area
789 	 * - Enable  DMA request status decoding for read
790 	 * - Set timings
791 	 */
792 	if (write_data)
793 		cfg[1] = FIELD_PREP(FMC2_CSQCFGR2_RCMD1, NAND_CMD_RNDIN);
794 	else
795 		cfg[1] = FIELD_PREP(FMC2_CSQCFGR2_RCMD1, NAND_CMD_RNDOUT) |
796 			 FMC2_CSQCFGR2_RCMD2EN |
797 			 FIELD_PREP(FMC2_CSQCFGR2_RCMD2, NAND_CMD_RNDOUTSTART) |
798 			 FMC2_CSQCFGR2_RCMD1T |
799 			 FMC2_CSQCFGR2_RCMD2T;
800 	if (!raw) {
801 		cfg[1] |= write_data ? 0 : FMC2_CSQCFGR2_DMASEN;
802 		cfg[1] |= FMC2_CSQCFGR2_SQSDTEN;
803 	}
804 
805 	/*
806 	 * - Set the number of sectors to be written
807 	 * - Set timings
808 	 */
809 	cfg[2] = FIELD_PREP(FMC2_CSQCFGR3_SNBR, chip->ecc.steps - 1);
810 	if (write_data) {
811 		cfg[2] |= FMC2_CSQCFGR3_RAC2T;
812 		if (chip->options & NAND_ROW_ADDR_3)
813 			cfg[2] |= FMC2_CSQCFGR3_AC5T;
814 		else
815 			cfg[2] |= FMC2_CSQCFGR3_AC4T;
816 	}
817 
818 	/*
819 	 * Set the fourth first address cycles
820 	 * Byte 1 and byte 2 => column, we start at 0x0
821 	 * Byte 3 and byte 4 => page
822 	 */
823 	cfg[3] = FIELD_PREP(FMC2_CSQCAR1_ADDC3, page);
824 	cfg[3] |= FIELD_PREP(FMC2_CSQCAR1_ADDC4, page >> 8);
825 
826 	/*
827 	 * - Set chip enable number
828 	 * - Set ECC byte offset in the spare area
829 	 * - Calculate the number of address cycles to be issued
830 	 * - Set byte 5 of address cycle if needed
831 	 */
832 	cfg[4] = FIELD_PREP(FMC2_CSQCAR2_NANDCEN, nfc->cs_sel);
833 	if (chip->options & NAND_BUSWIDTH_16)
834 		cfg[4] |= FIELD_PREP(FMC2_CSQCAR2_SAO, ecc_offset >> 1);
835 	else
836 		cfg[4] |= FIELD_PREP(FMC2_CSQCAR2_SAO, ecc_offset);
837 	if (chip->options & NAND_ROW_ADDR_3) {
838 		cfg[0] |= FIELD_PREP(FMC2_CSQCFGR1_ACYNBR, 5);
839 		cfg[4] |= FIELD_PREP(FMC2_CSQCAR2_ADDC5, page >> 16);
840 	} else {
841 		cfg[0] |= FIELD_PREP(FMC2_CSQCFGR1_ACYNBR, 4);
842 	}
843 
844 	regmap_bulk_write(nfc->regmap, FMC2_CSQCFGR1, cfg, 5);
845 }
846 
847 static void stm32_fmc2_nfc_dma_callback(void *arg)
848 {
849 	complete((struct completion *)arg);
850 }
851 
852 /* Read/write data from/to a page */
853 static int stm32_fmc2_nfc_xfer(struct nand_chip *chip, const u8 *buf,
854 			       int raw, bool write_data)
855 {
856 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
857 	struct dma_async_tx_descriptor *desc_data, *desc_ecc;
858 	struct scatterlist *sg;
859 	struct dma_chan *dma_ch = nfc->dma_rx_ch;
860 	enum dma_data_direction dma_data_dir = DMA_FROM_DEVICE;
861 	enum dma_transfer_direction dma_transfer_dir = DMA_DEV_TO_MEM;
862 	int eccsteps = chip->ecc.steps;
863 	int eccsize = chip->ecc.size;
864 	unsigned long timeout = msecs_to_jiffies(FMC2_TIMEOUT_MS);
865 	const u8 *p = buf;
866 	int s, ret;
867 
868 	/* Configure DMA data */
869 	if (write_data) {
870 		dma_data_dir = DMA_TO_DEVICE;
871 		dma_transfer_dir = DMA_MEM_TO_DEV;
872 		dma_ch = nfc->dma_tx_ch;
873 	}
874 
875 	for_each_sg(nfc->dma_data_sg.sgl, sg, eccsteps, s) {
876 		sg_set_buf(sg, p, eccsize);
877 		p += eccsize;
878 	}
879 
880 	ret = dma_map_sg(nfc->dev, nfc->dma_data_sg.sgl,
881 			 eccsteps, dma_data_dir);
882 	if (!ret)
883 		return -EIO;
884 
885 	desc_data = dmaengine_prep_slave_sg(dma_ch, nfc->dma_data_sg.sgl,
886 					    eccsteps, dma_transfer_dir,
887 					    DMA_PREP_INTERRUPT);
888 	if (!desc_data) {
889 		ret = -ENOMEM;
890 		goto err_unmap_data;
891 	}
892 
893 	reinit_completion(&nfc->dma_data_complete);
894 	reinit_completion(&nfc->complete);
895 	desc_data->callback = stm32_fmc2_nfc_dma_callback;
896 	desc_data->callback_param = &nfc->dma_data_complete;
897 	ret = dma_submit_error(dmaengine_submit(desc_data));
898 	if (ret)
899 		goto err_unmap_data;
900 
901 	dma_async_issue_pending(dma_ch);
902 
903 	if (!write_data && !raw) {
904 		/* Configure DMA ECC status */
905 		p = nfc->ecc_buf;
906 		for_each_sg(nfc->dma_ecc_sg.sgl, sg, eccsteps, s) {
907 			sg_set_buf(sg, p, nfc->dma_ecc_len);
908 			p += nfc->dma_ecc_len;
909 		}
910 
911 		ret = dma_map_sg(nfc->dev, nfc->dma_ecc_sg.sgl,
912 				 eccsteps, dma_data_dir);
913 		if (!ret) {
914 			ret = -EIO;
915 			goto err_unmap_data;
916 		}
917 
918 		desc_ecc = dmaengine_prep_slave_sg(nfc->dma_ecc_ch,
919 						   nfc->dma_ecc_sg.sgl,
920 						   eccsteps, dma_transfer_dir,
921 						   DMA_PREP_INTERRUPT);
922 		if (!desc_ecc) {
923 			ret = -ENOMEM;
924 			goto err_unmap_ecc;
925 		}
926 
927 		reinit_completion(&nfc->dma_ecc_complete);
928 		desc_ecc->callback = stm32_fmc2_nfc_dma_callback;
929 		desc_ecc->callback_param = &nfc->dma_ecc_complete;
930 		ret = dma_submit_error(dmaengine_submit(desc_ecc));
931 		if (ret)
932 			goto err_unmap_ecc;
933 
934 		dma_async_issue_pending(nfc->dma_ecc_ch);
935 	}
936 
937 	stm32_fmc2_nfc_clear_seq_irq(nfc);
938 	stm32_fmc2_nfc_enable_seq_irq(nfc);
939 
940 	/* Start the transfer */
941 	regmap_update_bits(nfc->regmap, FMC2_CSQCR,
942 			   FMC2_CSQCR_CSQSTART, FMC2_CSQCR_CSQSTART);
943 
944 	/* Wait end of sequencer transfer */
945 	if (!wait_for_completion_timeout(&nfc->complete, timeout)) {
946 		dev_err(nfc->dev, "seq timeout\n");
947 		stm32_fmc2_nfc_disable_seq_irq(nfc);
948 		dmaengine_terminate_all(dma_ch);
949 		if (!write_data && !raw)
950 			dmaengine_terminate_all(nfc->dma_ecc_ch);
951 		ret = -ETIMEDOUT;
952 		goto err_unmap_ecc;
953 	}
954 
955 	/* Wait DMA data transfer completion */
956 	if (!wait_for_completion_timeout(&nfc->dma_data_complete, timeout)) {
957 		dev_err(nfc->dev, "data DMA timeout\n");
958 		dmaengine_terminate_all(dma_ch);
959 		ret = -ETIMEDOUT;
960 	}
961 
962 	/* Wait DMA ECC transfer completion */
963 	if (!write_data && !raw) {
964 		if (!wait_for_completion_timeout(&nfc->dma_ecc_complete,
965 						 timeout)) {
966 			dev_err(nfc->dev, "ECC DMA timeout\n");
967 			dmaengine_terminate_all(nfc->dma_ecc_ch);
968 			ret = -ETIMEDOUT;
969 		}
970 	}
971 
972 err_unmap_ecc:
973 	if (!write_data && !raw)
974 		dma_unmap_sg(nfc->dev, nfc->dma_ecc_sg.sgl,
975 			     eccsteps, dma_data_dir);
976 
977 err_unmap_data:
978 	dma_unmap_sg(nfc->dev, nfc->dma_data_sg.sgl, eccsteps, dma_data_dir);
979 
980 	return ret;
981 }
982 
983 static int stm32_fmc2_nfc_seq_write(struct nand_chip *chip, const u8 *buf,
984 				    int oob_required, int page, int raw)
985 {
986 	struct mtd_info *mtd = nand_to_mtd(chip);
987 	int ret;
988 
989 	/* Configure the sequencer */
990 	stm32_fmc2_nfc_rw_page_init(chip, page, raw, true);
991 
992 	/* Write the page */
993 	ret = stm32_fmc2_nfc_xfer(chip, buf, raw, true);
994 	if (ret)
995 		return ret;
996 
997 	/* Write oob */
998 	if (oob_required) {
999 		ret = nand_change_write_column_op(chip, mtd->writesize,
1000 						  chip->oob_poi, mtd->oobsize,
1001 						  false);
1002 		if (ret)
1003 			return ret;
1004 	}
1005 
1006 	return nand_prog_page_end_op(chip);
1007 }
1008 
1009 static int stm32_fmc2_nfc_seq_write_page(struct nand_chip *chip, const u8 *buf,
1010 					 int oob_required, int page)
1011 {
1012 	int ret;
1013 
1014 	ret = stm32_fmc2_nfc_select_chip(chip, chip->cur_cs);
1015 	if (ret)
1016 		return ret;
1017 
1018 	return stm32_fmc2_nfc_seq_write(chip, buf, oob_required, page, false);
1019 }
1020 
1021 static int stm32_fmc2_nfc_seq_write_page_raw(struct nand_chip *chip,
1022 					     const u8 *buf, int oob_required,
1023 					     int page)
1024 {
1025 	int ret;
1026 
1027 	ret = stm32_fmc2_nfc_select_chip(chip, chip->cur_cs);
1028 	if (ret)
1029 		return ret;
1030 
1031 	return stm32_fmc2_nfc_seq_write(chip, buf, oob_required, page, true);
1032 }
1033 
1034 /* Get a status indicating which sectors have errors */
1035 static u16 stm32_fmc2_nfc_get_mapping_status(struct stm32_fmc2_nfc *nfc)
1036 {
1037 	u32 csqemsr;
1038 
1039 	regmap_read(nfc->regmap, FMC2_CSQEMSR, &csqemsr);
1040 
1041 	return FIELD_GET(FMC2_CSQEMSR_SEM, csqemsr);
1042 }
1043 
1044 static int stm32_fmc2_nfc_seq_correct(struct nand_chip *chip, u8 *dat,
1045 				      u8 *read_ecc, u8 *calc_ecc)
1046 {
1047 	struct mtd_info *mtd = nand_to_mtd(chip);
1048 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
1049 	int eccbytes = chip->ecc.bytes;
1050 	int eccsteps = chip->ecc.steps;
1051 	int eccstrength = chip->ecc.strength;
1052 	int i, s, eccsize = chip->ecc.size;
1053 	u32 *ecc_sta = (u32 *)nfc->ecc_buf;
1054 	u16 sta_map = stm32_fmc2_nfc_get_mapping_status(nfc);
1055 	unsigned int max_bitflips = 0;
1056 
1057 	for (i = 0, s = 0; s < eccsteps; s++, i += eccbytes, dat += eccsize) {
1058 		int stat = 0;
1059 
1060 		if (eccstrength == FMC2_ECC_HAM) {
1061 			/* Ecc_sta = FMC2_HECCR */
1062 			if (sta_map & BIT(s)) {
1063 				stm32_fmc2_nfc_ham_set_ecc(*ecc_sta,
1064 							   &calc_ecc[i]);
1065 				stat = stm32_fmc2_nfc_ham_correct(chip, dat,
1066 								  &read_ecc[i],
1067 								  &calc_ecc[i]);
1068 			}
1069 			ecc_sta++;
1070 		} else {
1071 			/*
1072 			 * Ecc_sta[0] = FMC2_BCHDSR0
1073 			 * Ecc_sta[1] = FMC2_BCHDSR1
1074 			 * Ecc_sta[2] = FMC2_BCHDSR2
1075 			 * Ecc_sta[3] = FMC2_BCHDSR3
1076 			 * Ecc_sta[4] = FMC2_BCHDSR4
1077 			 */
1078 			if (sta_map & BIT(s))
1079 				stat = stm32_fmc2_nfc_bch_decode(eccsize, dat,
1080 								 ecc_sta);
1081 			ecc_sta += 5;
1082 		}
1083 
1084 		if (stat == -EBADMSG)
1085 			/* Check for empty pages with bitflips */
1086 			stat = nand_check_erased_ecc_chunk(dat, eccsize,
1087 							   &read_ecc[i],
1088 							   eccbytes,
1089 							   NULL, 0,
1090 							   eccstrength);
1091 
1092 		if (stat < 0) {
1093 			mtd->ecc_stats.failed++;
1094 		} else {
1095 			mtd->ecc_stats.corrected += stat;
1096 			max_bitflips = max_t(unsigned int, max_bitflips, stat);
1097 		}
1098 	}
1099 
1100 	return max_bitflips;
1101 }
1102 
1103 static int stm32_fmc2_nfc_seq_read_page(struct nand_chip *chip, u8 *buf,
1104 					int oob_required, int page)
1105 {
1106 	struct mtd_info *mtd = nand_to_mtd(chip);
1107 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
1108 	u8 *ecc_calc = chip->ecc.calc_buf;
1109 	u8 *ecc_code = chip->ecc.code_buf;
1110 	u16 sta_map;
1111 	int ret;
1112 
1113 	ret = stm32_fmc2_nfc_select_chip(chip, chip->cur_cs);
1114 	if (ret)
1115 		return ret;
1116 
1117 	/* Configure the sequencer */
1118 	stm32_fmc2_nfc_rw_page_init(chip, page, 0, false);
1119 
1120 	/* Read the page */
1121 	ret = stm32_fmc2_nfc_xfer(chip, buf, 0, false);
1122 	if (ret)
1123 		return ret;
1124 
1125 	sta_map = stm32_fmc2_nfc_get_mapping_status(nfc);
1126 
1127 	/* Check if errors happen */
1128 	if (likely(!sta_map)) {
1129 		if (oob_required)
1130 			return nand_change_read_column_op(chip, mtd->writesize,
1131 							  chip->oob_poi,
1132 							  mtd->oobsize, false);
1133 
1134 		return 0;
1135 	}
1136 
1137 	/* Read oob */
1138 	ret = nand_change_read_column_op(chip, mtd->writesize,
1139 					 chip->oob_poi, mtd->oobsize, false);
1140 	if (ret)
1141 		return ret;
1142 
1143 	ret = mtd_ooblayout_get_eccbytes(mtd, ecc_code, chip->oob_poi, 0,
1144 					 chip->ecc.total);
1145 	if (ret)
1146 		return ret;
1147 
1148 	/* Correct data */
1149 	return chip->ecc.correct(chip, buf, ecc_code, ecc_calc);
1150 }
1151 
1152 static int stm32_fmc2_nfc_seq_read_page_raw(struct nand_chip *chip, u8 *buf,
1153 					    int oob_required, int page)
1154 {
1155 	struct mtd_info *mtd = nand_to_mtd(chip);
1156 	int ret;
1157 
1158 	ret = stm32_fmc2_nfc_select_chip(chip, chip->cur_cs);
1159 	if (ret)
1160 		return ret;
1161 
1162 	/* Configure the sequencer */
1163 	stm32_fmc2_nfc_rw_page_init(chip, page, 1, false);
1164 
1165 	/* Read the page */
1166 	ret = stm32_fmc2_nfc_xfer(chip, buf, 1, false);
1167 	if (ret)
1168 		return ret;
1169 
1170 	/* Read oob */
1171 	if (oob_required)
1172 		return nand_change_read_column_op(chip, mtd->writesize,
1173 						  chip->oob_poi, mtd->oobsize,
1174 						  false);
1175 
1176 	return 0;
1177 }
1178 
1179 static irqreturn_t stm32_fmc2_nfc_irq(int irq, void *dev_id)
1180 {
1181 	struct stm32_fmc2_nfc *nfc = (struct stm32_fmc2_nfc *)dev_id;
1182 
1183 	if (nfc->irq_state == FMC2_IRQ_SEQ)
1184 		/* Sequencer is used */
1185 		stm32_fmc2_nfc_disable_seq_irq(nfc);
1186 	else if (nfc->irq_state == FMC2_IRQ_BCH)
1187 		/* BCH is used */
1188 		stm32_fmc2_nfc_disable_bch_irq(nfc);
1189 
1190 	complete(&nfc->complete);
1191 
1192 	return IRQ_HANDLED;
1193 }
1194 
1195 static void stm32_fmc2_nfc_read_data(struct nand_chip *chip, void *buf,
1196 				     unsigned int len, bool force_8bit)
1197 {
1198 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
1199 	void __iomem *io_addr_r = nfc->data_base[nfc->cs_sel];
1200 
1201 	if (force_8bit && chip->options & NAND_BUSWIDTH_16)
1202 		/* Reconfigure bus width to 8-bit */
1203 		stm32_fmc2_nfc_set_buswidth_16(nfc, false);
1204 
1205 	if (!IS_ALIGNED((uintptr_t)buf, sizeof(u32))) {
1206 		if (!IS_ALIGNED((uintptr_t)buf, sizeof(u16)) && len) {
1207 			*(u8 *)buf = readb_relaxed(io_addr_r);
1208 			buf += sizeof(u8);
1209 			len -= sizeof(u8);
1210 		}
1211 
1212 		if (!IS_ALIGNED((uintptr_t)buf, sizeof(u32)) &&
1213 		    len >= sizeof(u16)) {
1214 			*(u16 *)buf = readw_relaxed(io_addr_r);
1215 			buf += sizeof(u16);
1216 			len -= sizeof(u16);
1217 		}
1218 	}
1219 
1220 	/* Buf is aligned */
1221 	while (len >= sizeof(u32)) {
1222 		*(u32 *)buf = readl_relaxed(io_addr_r);
1223 		buf += sizeof(u32);
1224 		len -= sizeof(u32);
1225 	}
1226 
1227 	/* Read remaining bytes */
1228 	if (len >= sizeof(u16)) {
1229 		*(u16 *)buf = readw_relaxed(io_addr_r);
1230 		buf += sizeof(u16);
1231 		len -= sizeof(u16);
1232 	}
1233 
1234 	if (len)
1235 		*(u8 *)buf = readb_relaxed(io_addr_r);
1236 
1237 	if (force_8bit && chip->options & NAND_BUSWIDTH_16)
1238 		/* Reconfigure bus width to 16-bit */
1239 		stm32_fmc2_nfc_set_buswidth_16(nfc, true);
1240 }
1241 
1242 static void stm32_fmc2_nfc_write_data(struct nand_chip *chip, const void *buf,
1243 				      unsigned int len, bool force_8bit)
1244 {
1245 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
1246 	void __iomem *io_addr_w = nfc->data_base[nfc->cs_sel];
1247 
1248 	if (force_8bit && chip->options & NAND_BUSWIDTH_16)
1249 		/* Reconfigure bus width to 8-bit */
1250 		stm32_fmc2_nfc_set_buswidth_16(nfc, false);
1251 
1252 	if (!IS_ALIGNED((uintptr_t)buf, sizeof(u32))) {
1253 		if (!IS_ALIGNED((uintptr_t)buf, sizeof(u16)) && len) {
1254 			writeb_relaxed(*(u8 *)buf, io_addr_w);
1255 			buf += sizeof(u8);
1256 			len -= sizeof(u8);
1257 		}
1258 
1259 		if (!IS_ALIGNED((uintptr_t)buf, sizeof(u32)) &&
1260 		    len >= sizeof(u16)) {
1261 			writew_relaxed(*(u16 *)buf, io_addr_w);
1262 			buf += sizeof(u16);
1263 			len -= sizeof(u16);
1264 		}
1265 	}
1266 
1267 	/* Buf is aligned */
1268 	while (len >= sizeof(u32)) {
1269 		writel_relaxed(*(u32 *)buf, io_addr_w);
1270 		buf += sizeof(u32);
1271 		len -= sizeof(u32);
1272 	}
1273 
1274 	/* Write remaining bytes */
1275 	if (len >= sizeof(u16)) {
1276 		writew_relaxed(*(u16 *)buf, io_addr_w);
1277 		buf += sizeof(u16);
1278 		len -= sizeof(u16);
1279 	}
1280 
1281 	if (len)
1282 		writeb_relaxed(*(u8 *)buf, io_addr_w);
1283 
1284 	if (force_8bit && chip->options & NAND_BUSWIDTH_16)
1285 		/* Reconfigure bus width to 16-bit */
1286 		stm32_fmc2_nfc_set_buswidth_16(nfc, true);
1287 }
1288 
1289 static int stm32_fmc2_nfc_waitrdy(struct nand_chip *chip,
1290 				  unsigned long timeout_ms)
1291 {
1292 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
1293 	const struct nand_sdr_timings *timings;
1294 	u32 isr, sr;
1295 
1296 	/* Check if there is no pending requests to the NAND flash */
1297 	if (regmap_read_poll_timeout(nfc->regmap, FMC2_SR, sr,
1298 				     sr & FMC2_SR_NWRF, 1,
1299 				     1000 * FMC2_TIMEOUT_MS))
1300 		dev_warn(nfc->dev, "Waitrdy timeout\n");
1301 
1302 	/* Wait tWB before R/B# signal is low */
1303 	timings = nand_get_sdr_timings(nand_get_interface_config(chip));
1304 	ndelay(PSEC_TO_NSEC(timings->tWB_max));
1305 
1306 	/* R/B# signal is low, clear high level flag */
1307 	regmap_write(nfc->regmap, FMC2_ICR, FMC2_ICR_CIHLF);
1308 
1309 	/* Wait R/B# signal is high */
1310 	return regmap_read_poll_timeout(nfc->regmap, FMC2_ISR, isr,
1311 					isr & FMC2_ISR_IHLF, 5,
1312 					1000 * FMC2_TIMEOUT_MS);
1313 }
1314 
1315 static int stm32_fmc2_nfc_exec_op(struct nand_chip *chip,
1316 				  const struct nand_operation *op,
1317 				  bool check_only)
1318 {
1319 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
1320 	const struct nand_op_instr *instr = NULL;
1321 	unsigned int op_id, i, timeout;
1322 	int ret;
1323 
1324 	if (check_only)
1325 		return 0;
1326 
1327 	ret = stm32_fmc2_nfc_select_chip(chip, op->cs);
1328 	if (ret)
1329 		return ret;
1330 
1331 	for (op_id = 0; op_id < op->ninstrs; op_id++) {
1332 		instr = &op->instrs[op_id];
1333 
1334 		switch (instr->type) {
1335 		case NAND_OP_CMD_INSTR:
1336 			writeb_relaxed(instr->ctx.cmd.opcode,
1337 				       nfc->cmd_base[nfc->cs_sel]);
1338 			break;
1339 
1340 		case NAND_OP_ADDR_INSTR:
1341 			for (i = 0; i < instr->ctx.addr.naddrs; i++)
1342 				writeb_relaxed(instr->ctx.addr.addrs[i],
1343 					       nfc->addr_base[nfc->cs_sel]);
1344 			break;
1345 
1346 		case NAND_OP_DATA_IN_INSTR:
1347 			stm32_fmc2_nfc_read_data(chip, instr->ctx.data.buf.in,
1348 						 instr->ctx.data.len,
1349 						 instr->ctx.data.force_8bit);
1350 			break;
1351 
1352 		case NAND_OP_DATA_OUT_INSTR:
1353 			stm32_fmc2_nfc_write_data(chip, instr->ctx.data.buf.out,
1354 						  instr->ctx.data.len,
1355 						  instr->ctx.data.force_8bit);
1356 			break;
1357 
1358 		case NAND_OP_WAITRDY_INSTR:
1359 			timeout = instr->ctx.waitrdy.timeout_ms;
1360 			ret = stm32_fmc2_nfc_waitrdy(chip, timeout);
1361 			break;
1362 		}
1363 	}
1364 
1365 	return ret;
1366 }
1367 
1368 static void stm32_fmc2_nfc_init(struct stm32_fmc2_nfc *nfc)
1369 {
1370 	u32 pcr;
1371 
1372 	regmap_read(nfc->regmap, FMC2_PCR, &pcr);
1373 
1374 	/* Set CS used to undefined */
1375 	nfc->cs_sel = -1;
1376 
1377 	/* Enable wait feature and nand flash memory bank */
1378 	pcr |= FMC2_PCR_PWAITEN;
1379 	pcr |= FMC2_PCR_PBKEN;
1380 
1381 	/* Set buswidth to 8 bits mode for identification */
1382 	pcr &= ~FMC2_PCR_PWID;
1383 
1384 	/* ECC logic is disabled */
1385 	pcr &= ~FMC2_PCR_ECCEN;
1386 
1387 	/* Default mode */
1388 	pcr &= ~FMC2_PCR_ECCALG;
1389 	pcr &= ~FMC2_PCR_BCHECC;
1390 	pcr &= ~FMC2_PCR_WEN;
1391 
1392 	/* Set default ECC sector size */
1393 	pcr &= ~FMC2_PCR_ECCSS;
1394 	pcr |= FIELD_PREP(FMC2_PCR_ECCSS, FMC2_PCR_ECCSS_2048);
1395 
1396 	/* Set default tclr/tar timings */
1397 	pcr &= ~FMC2_PCR_TCLR;
1398 	pcr |= FIELD_PREP(FMC2_PCR_TCLR, FMC2_PCR_TCLR_DEFAULT);
1399 	pcr &= ~FMC2_PCR_TAR;
1400 	pcr |= FIELD_PREP(FMC2_PCR_TAR, FMC2_PCR_TAR_DEFAULT);
1401 
1402 	/* Enable FMC2 controller */
1403 	if (nfc->dev == nfc->cdev)
1404 		regmap_update_bits(nfc->regmap, FMC2_BCR1,
1405 				   FMC2_BCR1_FMC2EN, FMC2_BCR1_FMC2EN);
1406 
1407 	regmap_write(nfc->regmap, FMC2_PCR, pcr);
1408 	regmap_write(nfc->regmap, FMC2_PMEM, FMC2_PMEM_DEFAULT);
1409 	regmap_write(nfc->regmap, FMC2_PATT, FMC2_PATT_DEFAULT);
1410 }
1411 
1412 static void stm32_fmc2_nfc_calc_timings(struct nand_chip *chip,
1413 					const struct nand_sdr_timings *sdrt)
1414 {
1415 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
1416 	struct stm32_fmc2_nand *nand = to_fmc2_nand(chip);
1417 	struct stm32_fmc2_timings *tims = &nand->timings;
1418 	unsigned long hclk = clk_get_rate(nfc->clk);
1419 	unsigned long hclkp = NSEC_PER_SEC / (hclk / 1000);
1420 	unsigned long timing, tar, tclr, thiz, twait;
1421 	unsigned long tset_mem, tset_att, thold_mem, thold_att;
1422 
1423 	tar = max_t(unsigned long, hclkp, sdrt->tAR_min);
1424 	timing = DIV_ROUND_UP(tar, hclkp) - 1;
1425 	tims->tar = min_t(unsigned long, timing, FMC2_PCR_TIMING_MASK);
1426 
1427 	tclr = max_t(unsigned long, hclkp, sdrt->tCLR_min);
1428 	timing = DIV_ROUND_UP(tclr, hclkp) - 1;
1429 	tims->tclr = min_t(unsigned long, timing, FMC2_PCR_TIMING_MASK);
1430 
1431 	tims->thiz = FMC2_THIZ;
1432 	thiz = (tims->thiz + 1) * hclkp;
1433 
1434 	/*
1435 	 * tWAIT > tRP
1436 	 * tWAIT > tWP
1437 	 * tWAIT > tREA + tIO
1438 	 */
1439 	twait = max_t(unsigned long, hclkp, sdrt->tRP_min);
1440 	twait = max_t(unsigned long, twait, sdrt->tWP_min);
1441 	twait = max_t(unsigned long, twait, sdrt->tREA_max + FMC2_TIO);
1442 	timing = DIV_ROUND_UP(twait, hclkp);
1443 	tims->twait = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
1444 
1445 	/*
1446 	 * tSETUP_MEM > tCS - tWAIT
1447 	 * tSETUP_MEM > tALS - tWAIT
1448 	 * tSETUP_MEM > tDS - (tWAIT - tHIZ)
1449 	 */
1450 	tset_mem = hclkp;
1451 	if (sdrt->tCS_min > twait && (tset_mem < sdrt->tCS_min - twait))
1452 		tset_mem = sdrt->tCS_min - twait;
1453 	if (sdrt->tALS_min > twait && (tset_mem < sdrt->tALS_min - twait))
1454 		tset_mem = sdrt->tALS_min - twait;
1455 	if (twait > thiz && (sdrt->tDS_min > twait - thiz) &&
1456 	    (tset_mem < sdrt->tDS_min - (twait - thiz)))
1457 		tset_mem = sdrt->tDS_min - (twait - thiz);
1458 	timing = DIV_ROUND_UP(tset_mem, hclkp);
1459 	tims->tset_mem = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
1460 
1461 	/*
1462 	 * tHOLD_MEM > tCH
1463 	 * tHOLD_MEM > tREH - tSETUP_MEM
1464 	 * tHOLD_MEM > max(tRC, tWC) - (tSETUP_MEM + tWAIT)
1465 	 */
1466 	thold_mem = max_t(unsigned long, hclkp, sdrt->tCH_min);
1467 	if (sdrt->tREH_min > tset_mem &&
1468 	    (thold_mem < sdrt->tREH_min - tset_mem))
1469 		thold_mem = sdrt->tREH_min - tset_mem;
1470 	if ((sdrt->tRC_min > tset_mem + twait) &&
1471 	    (thold_mem < sdrt->tRC_min - (tset_mem + twait)))
1472 		thold_mem = sdrt->tRC_min - (tset_mem + twait);
1473 	if ((sdrt->tWC_min > tset_mem + twait) &&
1474 	    (thold_mem < sdrt->tWC_min - (tset_mem + twait)))
1475 		thold_mem = sdrt->tWC_min - (tset_mem + twait);
1476 	timing = DIV_ROUND_UP(thold_mem, hclkp);
1477 	tims->thold_mem = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
1478 
1479 	/*
1480 	 * tSETUP_ATT > tCS - tWAIT
1481 	 * tSETUP_ATT > tCLS - tWAIT
1482 	 * tSETUP_ATT > tALS - tWAIT
1483 	 * tSETUP_ATT > tRHW - tHOLD_MEM
1484 	 * tSETUP_ATT > tDS - (tWAIT - tHIZ)
1485 	 */
1486 	tset_att = hclkp;
1487 	if (sdrt->tCS_min > twait && (tset_att < sdrt->tCS_min - twait))
1488 		tset_att = sdrt->tCS_min - twait;
1489 	if (sdrt->tCLS_min > twait && (tset_att < sdrt->tCLS_min - twait))
1490 		tset_att = sdrt->tCLS_min - twait;
1491 	if (sdrt->tALS_min > twait && (tset_att < sdrt->tALS_min - twait))
1492 		tset_att = sdrt->tALS_min - twait;
1493 	if (sdrt->tRHW_min > thold_mem &&
1494 	    (tset_att < sdrt->tRHW_min - thold_mem))
1495 		tset_att = sdrt->tRHW_min - thold_mem;
1496 	if (twait > thiz && (sdrt->tDS_min > twait - thiz) &&
1497 	    (tset_att < sdrt->tDS_min - (twait - thiz)))
1498 		tset_att = sdrt->tDS_min - (twait - thiz);
1499 	timing = DIV_ROUND_UP(tset_att, hclkp);
1500 	tims->tset_att = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
1501 
1502 	/*
1503 	 * tHOLD_ATT > tALH
1504 	 * tHOLD_ATT > tCH
1505 	 * tHOLD_ATT > tCLH
1506 	 * tHOLD_ATT > tCOH
1507 	 * tHOLD_ATT > tDH
1508 	 * tHOLD_ATT > tWB + tIO + tSYNC - tSETUP_MEM
1509 	 * tHOLD_ATT > tADL - tSETUP_MEM
1510 	 * tHOLD_ATT > tWH - tSETUP_MEM
1511 	 * tHOLD_ATT > tWHR - tSETUP_MEM
1512 	 * tHOLD_ATT > tRC - (tSETUP_ATT + tWAIT)
1513 	 * tHOLD_ATT > tWC - (tSETUP_ATT + tWAIT)
1514 	 */
1515 	thold_att = max_t(unsigned long, hclkp, sdrt->tALH_min);
1516 	thold_att = max_t(unsigned long, thold_att, sdrt->tCH_min);
1517 	thold_att = max_t(unsigned long, thold_att, sdrt->tCLH_min);
1518 	thold_att = max_t(unsigned long, thold_att, sdrt->tCOH_min);
1519 	thold_att = max_t(unsigned long, thold_att, sdrt->tDH_min);
1520 	if ((sdrt->tWB_max + FMC2_TIO + FMC2_TSYNC > tset_mem) &&
1521 	    (thold_att < sdrt->tWB_max + FMC2_TIO + FMC2_TSYNC - tset_mem))
1522 		thold_att = sdrt->tWB_max + FMC2_TIO + FMC2_TSYNC - tset_mem;
1523 	if (sdrt->tADL_min > tset_mem &&
1524 	    (thold_att < sdrt->tADL_min - tset_mem))
1525 		thold_att = sdrt->tADL_min - tset_mem;
1526 	if (sdrt->tWH_min > tset_mem &&
1527 	    (thold_att < sdrt->tWH_min - tset_mem))
1528 		thold_att = sdrt->tWH_min - tset_mem;
1529 	if (sdrt->tWHR_min > tset_mem &&
1530 	    (thold_att < sdrt->tWHR_min - tset_mem))
1531 		thold_att = sdrt->tWHR_min - tset_mem;
1532 	if ((sdrt->tRC_min > tset_att + twait) &&
1533 	    (thold_att < sdrt->tRC_min - (tset_att + twait)))
1534 		thold_att = sdrt->tRC_min - (tset_att + twait);
1535 	if ((sdrt->tWC_min > tset_att + twait) &&
1536 	    (thold_att < sdrt->tWC_min - (tset_att + twait)))
1537 		thold_att = sdrt->tWC_min - (tset_att + twait);
1538 	timing = DIV_ROUND_UP(thold_att, hclkp);
1539 	tims->thold_att = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
1540 }
1541 
1542 static int stm32_fmc2_nfc_setup_interface(struct nand_chip *chip, int chipnr,
1543 					  const struct nand_interface_config *conf)
1544 {
1545 	const struct nand_sdr_timings *sdrt;
1546 
1547 	sdrt = nand_get_sdr_timings(conf);
1548 	if (IS_ERR(sdrt))
1549 		return PTR_ERR(sdrt);
1550 
1551 	if (conf->timings.mode > 3)
1552 		return -EOPNOTSUPP;
1553 
1554 	if (chipnr == NAND_DATA_IFACE_CHECK_ONLY)
1555 		return 0;
1556 
1557 	stm32_fmc2_nfc_calc_timings(chip, sdrt);
1558 	stm32_fmc2_nfc_timings_init(chip);
1559 
1560 	return 0;
1561 }
1562 
1563 static int stm32_fmc2_nfc_dma_setup(struct stm32_fmc2_nfc *nfc)
1564 {
1565 	struct dma_slave_caps caps;
1566 	int ret = 0;
1567 
1568 	nfc->dma_tx_ch = dma_request_chan(nfc->dev, "tx");
1569 	if (IS_ERR(nfc->dma_tx_ch)) {
1570 		ret = PTR_ERR(nfc->dma_tx_ch);
1571 		if (ret != -ENODEV && ret != -EPROBE_DEFER)
1572 			dev_err(nfc->dev,
1573 				"failed to request tx DMA channel: %d\n", ret);
1574 		nfc->dma_tx_ch = NULL;
1575 		goto err_dma;
1576 	}
1577 
1578 	ret = dma_get_slave_caps(nfc->dma_tx_ch, &caps);
1579 	if (ret)
1580 		return ret;
1581 	nfc->tx_dma_max_burst = caps.max_burst;
1582 
1583 	nfc->dma_rx_ch = dma_request_chan(nfc->dev, "rx");
1584 	if (IS_ERR(nfc->dma_rx_ch)) {
1585 		ret = PTR_ERR(nfc->dma_rx_ch);
1586 		if (ret != -ENODEV && ret != -EPROBE_DEFER)
1587 			dev_err(nfc->dev,
1588 				"failed to request rx DMA channel: %d\n", ret);
1589 		nfc->dma_rx_ch = NULL;
1590 		goto err_dma;
1591 	}
1592 
1593 	ret = dma_get_slave_caps(nfc->dma_rx_ch, &caps);
1594 	if (ret)
1595 		return ret;
1596 	nfc->rx_dma_max_burst = caps.max_burst;
1597 
1598 	nfc->dma_ecc_ch = dma_request_chan(nfc->dev, "ecc");
1599 	if (IS_ERR(nfc->dma_ecc_ch)) {
1600 		ret = PTR_ERR(nfc->dma_ecc_ch);
1601 		if (ret != -ENODEV && ret != -EPROBE_DEFER)
1602 			dev_err(nfc->dev,
1603 				"failed to request ecc DMA channel: %d\n", ret);
1604 		nfc->dma_ecc_ch = NULL;
1605 		goto err_dma;
1606 	}
1607 
1608 	ret = sg_alloc_table(&nfc->dma_ecc_sg, FMC2_MAX_SG, GFP_KERNEL);
1609 	if (ret)
1610 		return ret;
1611 
1612 	/* Allocate a buffer to store ECC status registers */
1613 	nfc->ecc_buf = devm_kzalloc(nfc->dev, FMC2_MAX_ECC_BUF_LEN, GFP_KERNEL);
1614 	if (!nfc->ecc_buf)
1615 		return -ENOMEM;
1616 
1617 	ret = sg_alloc_table(&nfc->dma_data_sg, FMC2_MAX_SG, GFP_KERNEL);
1618 	if (ret)
1619 		return ret;
1620 
1621 	init_completion(&nfc->dma_data_complete);
1622 	init_completion(&nfc->dma_ecc_complete);
1623 
1624 	return 0;
1625 
1626 err_dma:
1627 	if (ret == -ENODEV) {
1628 		dev_warn(nfc->dev,
1629 			 "DMAs not defined in the DT, polling mode is used\n");
1630 		ret = 0;
1631 	}
1632 
1633 	return ret;
1634 }
1635 
1636 static void stm32_fmc2_nfc_nand_callbacks_setup(struct nand_chip *chip)
1637 {
1638 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
1639 
1640 	/*
1641 	 * Specific callbacks to read/write a page depending on
1642 	 * the mode (polling/sequencer) and the algo used (Hamming, BCH).
1643 	 */
1644 	if (nfc->dma_tx_ch && nfc->dma_rx_ch && nfc->dma_ecc_ch) {
1645 		/* DMA => use sequencer mode callbacks */
1646 		chip->ecc.correct = stm32_fmc2_nfc_seq_correct;
1647 		chip->ecc.write_page = stm32_fmc2_nfc_seq_write_page;
1648 		chip->ecc.read_page = stm32_fmc2_nfc_seq_read_page;
1649 		chip->ecc.write_page_raw = stm32_fmc2_nfc_seq_write_page_raw;
1650 		chip->ecc.read_page_raw = stm32_fmc2_nfc_seq_read_page_raw;
1651 	} else {
1652 		/* No DMA => use polling mode callbacks */
1653 		chip->ecc.hwctl = stm32_fmc2_nfc_hwctl;
1654 		if (chip->ecc.strength == FMC2_ECC_HAM) {
1655 			/* Hamming is used */
1656 			chip->ecc.calculate = stm32_fmc2_nfc_ham_calculate;
1657 			chip->ecc.correct = stm32_fmc2_nfc_ham_correct;
1658 			chip->ecc.options |= NAND_ECC_GENERIC_ERASED_CHECK;
1659 		} else {
1660 			/* BCH is used */
1661 			chip->ecc.calculate = stm32_fmc2_nfc_bch_calculate;
1662 			chip->ecc.correct = stm32_fmc2_nfc_bch_correct;
1663 			chip->ecc.read_page = stm32_fmc2_nfc_read_page;
1664 		}
1665 	}
1666 
1667 	/* Specific configurations depending on the algo used */
1668 	if (chip->ecc.strength == FMC2_ECC_HAM)
1669 		chip->ecc.bytes = chip->options & NAND_BUSWIDTH_16 ? 4 : 3;
1670 	else if (chip->ecc.strength == FMC2_ECC_BCH8)
1671 		chip->ecc.bytes = chip->options & NAND_BUSWIDTH_16 ? 14 : 13;
1672 	else
1673 		chip->ecc.bytes = chip->options & NAND_BUSWIDTH_16 ? 8 : 7;
1674 }
1675 
1676 static int stm32_fmc2_nfc_ooblayout_ecc(struct mtd_info *mtd, int section,
1677 					struct mtd_oob_region *oobregion)
1678 {
1679 	struct nand_chip *chip = mtd_to_nand(mtd);
1680 	struct nand_ecc_ctrl *ecc = &chip->ecc;
1681 
1682 	if (section)
1683 		return -ERANGE;
1684 
1685 	oobregion->length = ecc->total;
1686 	oobregion->offset = FMC2_BBM_LEN;
1687 
1688 	return 0;
1689 }
1690 
1691 static int stm32_fmc2_nfc_ooblayout_free(struct mtd_info *mtd, int section,
1692 					 struct mtd_oob_region *oobregion)
1693 {
1694 	struct nand_chip *chip = mtd_to_nand(mtd);
1695 	struct nand_ecc_ctrl *ecc = &chip->ecc;
1696 
1697 	if (section)
1698 		return -ERANGE;
1699 
1700 	oobregion->length = mtd->oobsize - ecc->total - FMC2_BBM_LEN;
1701 	oobregion->offset = ecc->total + FMC2_BBM_LEN;
1702 
1703 	return 0;
1704 }
1705 
1706 static const struct mtd_ooblayout_ops stm32_fmc2_nfc_ooblayout_ops = {
1707 	.ecc = stm32_fmc2_nfc_ooblayout_ecc,
1708 	.free = stm32_fmc2_nfc_ooblayout_free,
1709 };
1710 
1711 static int stm32_fmc2_nfc_calc_ecc_bytes(int step_size, int strength)
1712 {
1713 	/* Hamming */
1714 	if (strength == FMC2_ECC_HAM)
1715 		return 4;
1716 
1717 	/* BCH8 */
1718 	if (strength == FMC2_ECC_BCH8)
1719 		return 14;
1720 
1721 	/* BCH4 */
1722 	return 8;
1723 }
1724 
1725 NAND_ECC_CAPS_SINGLE(stm32_fmc2_nfc_ecc_caps, stm32_fmc2_nfc_calc_ecc_bytes,
1726 		     FMC2_ECC_STEP_SIZE,
1727 		     FMC2_ECC_HAM, FMC2_ECC_BCH4, FMC2_ECC_BCH8);
1728 
1729 static int stm32_fmc2_nfc_attach_chip(struct nand_chip *chip)
1730 {
1731 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
1732 	struct mtd_info *mtd = nand_to_mtd(chip);
1733 	int ret;
1734 
1735 	/*
1736 	 * Only NAND_ECC_ENGINE_TYPE_ON_HOST mode is actually supported
1737 	 * Hamming => ecc.strength = 1
1738 	 * BCH4 => ecc.strength = 4
1739 	 * BCH8 => ecc.strength = 8
1740 	 * ECC sector size = 512
1741 	 */
1742 	if (chip->ecc.engine_type != NAND_ECC_ENGINE_TYPE_ON_HOST) {
1743 		dev_err(nfc->dev,
1744 			"nand_ecc_engine_type is not well defined in the DT\n");
1745 		return -EINVAL;
1746 	}
1747 
1748 	/* Default ECC settings in case they are not set in the device tree */
1749 	if (!chip->ecc.size)
1750 		chip->ecc.size = FMC2_ECC_STEP_SIZE;
1751 
1752 	if (!chip->ecc.strength)
1753 		chip->ecc.strength = FMC2_ECC_BCH8;
1754 
1755 	ret = nand_ecc_choose_conf(chip, &stm32_fmc2_nfc_ecc_caps,
1756 				   mtd->oobsize - FMC2_BBM_LEN);
1757 	if (ret) {
1758 		dev_err(nfc->dev, "no valid ECC settings set\n");
1759 		return ret;
1760 	}
1761 
1762 	if (mtd->writesize / chip->ecc.size > FMC2_MAX_SG) {
1763 		dev_err(nfc->dev, "nand page size is not supported\n");
1764 		return -EINVAL;
1765 	}
1766 
1767 	if (chip->bbt_options & NAND_BBT_USE_FLASH)
1768 		chip->bbt_options |= NAND_BBT_NO_OOB;
1769 
1770 	stm32_fmc2_nfc_nand_callbacks_setup(chip);
1771 
1772 	mtd_set_ooblayout(mtd, &stm32_fmc2_nfc_ooblayout_ops);
1773 
1774 	stm32_fmc2_nfc_setup(chip);
1775 
1776 	return 0;
1777 }
1778 
1779 static const struct nand_controller_ops stm32_fmc2_nfc_controller_ops = {
1780 	.attach_chip = stm32_fmc2_nfc_attach_chip,
1781 	.exec_op = stm32_fmc2_nfc_exec_op,
1782 	.setup_interface = stm32_fmc2_nfc_setup_interface,
1783 };
1784 
1785 static void stm32_fmc2_nfc_wp_enable(struct stm32_fmc2_nand *nand)
1786 {
1787 	if (nand->wp_gpio)
1788 		gpiod_set_value(nand->wp_gpio, 1);
1789 }
1790 
1791 static void stm32_fmc2_nfc_wp_disable(struct stm32_fmc2_nand *nand)
1792 {
1793 	if (nand->wp_gpio)
1794 		gpiod_set_value(nand->wp_gpio, 0);
1795 }
1796 
1797 static int stm32_fmc2_nfc_parse_child(struct stm32_fmc2_nfc *nfc,
1798 				      struct device_node *dn)
1799 {
1800 	struct stm32_fmc2_nand *nand = &nfc->nand;
1801 	u32 cs;
1802 	int ret, i;
1803 
1804 	if (!of_get_property(dn, "reg", &nand->ncs))
1805 		return -EINVAL;
1806 
1807 	nand->ncs /= sizeof(u32);
1808 	if (!nand->ncs) {
1809 		dev_err(nfc->dev, "invalid reg property size\n");
1810 		return -EINVAL;
1811 	}
1812 
1813 	for (i = 0; i < nand->ncs; i++) {
1814 		ret = of_property_read_u32_index(dn, "reg", i, &cs);
1815 		if (ret) {
1816 			dev_err(nfc->dev, "could not retrieve reg property: %d\n",
1817 				ret);
1818 			return ret;
1819 		}
1820 
1821 		if (cs >= nfc->data->max_ncs) {
1822 			dev_err(nfc->dev, "invalid reg value: %d\n", cs);
1823 			return -EINVAL;
1824 		}
1825 
1826 		if (nfc->cs_assigned & BIT(cs)) {
1827 			dev_err(nfc->dev, "cs already assigned: %d\n", cs);
1828 			return -EINVAL;
1829 		}
1830 
1831 		nfc->cs_assigned |= BIT(cs);
1832 		nand->cs_used[i] = cs;
1833 	}
1834 
1835 	nand->wp_gpio = devm_fwnode_gpiod_get(nfc->dev, of_fwnode_handle(dn),
1836 					      "wp", GPIOD_OUT_HIGH, "wp");
1837 	if (IS_ERR(nand->wp_gpio)) {
1838 		ret = PTR_ERR(nand->wp_gpio);
1839 		if (ret != -ENOENT)
1840 			return dev_err_probe(nfc->dev, ret,
1841 					     "failed to request WP GPIO\n");
1842 
1843 		nand->wp_gpio = NULL;
1844 	}
1845 
1846 	nand_set_flash_node(&nand->chip, dn);
1847 
1848 	return 0;
1849 }
1850 
1851 static int stm32_fmc2_nfc_parse_dt(struct stm32_fmc2_nfc *nfc)
1852 {
1853 	struct device_node *dn = nfc->dev->of_node;
1854 	struct device_node *child;
1855 	int nchips = of_get_child_count(dn);
1856 	int ret = 0;
1857 
1858 	if (!nchips) {
1859 		dev_err(nfc->dev, "NAND chip not defined\n");
1860 		return -EINVAL;
1861 	}
1862 
1863 	if (nchips > 1) {
1864 		dev_err(nfc->dev, "too many NAND chips defined\n");
1865 		return -EINVAL;
1866 	}
1867 
1868 	for_each_child_of_node(dn, child) {
1869 		ret = stm32_fmc2_nfc_parse_child(nfc, child);
1870 		if (ret < 0) {
1871 			of_node_put(child);
1872 			return ret;
1873 		}
1874 	}
1875 
1876 	return ret;
1877 }
1878 
1879 static int stm32_fmc2_nfc_set_cdev(struct stm32_fmc2_nfc *nfc)
1880 {
1881 	struct device *dev = nfc->dev;
1882 	bool ebi_found = false;
1883 
1884 	if (dev->parent && of_device_is_compatible(dev->parent->of_node,
1885 						   "st,stm32mp1-fmc2-ebi"))
1886 		ebi_found = true;
1887 
1888 	if (of_device_is_compatible(dev->of_node, "st,stm32mp1-fmc2-nfc")) {
1889 		if (ebi_found) {
1890 			nfc->cdev = dev->parent;
1891 
1892 			return 0;
1893 		}
1894 
1895 		return -EINVAL;
1896 	}
1897 
1898 	if (ebi_found)
1899 		return -EINVAL;
1900 
1901 	nfc->cdev = dev;
1902 
1903 	return 0;
1904 }
1905 
1906 static int stm32_fmc2_nfc_probe(struct platform_device *pdev)
1907 {
1908 	struct device *dev = &pdev->dev;
1909 	struct reset_control *rstc;
1910 	struct stm32_fmc2_nfc *nfc;
1911 	struct stm32_fmc2_nand *nand;
1912 	struct resource *res;
1913 	struct mtd_info *mtd;
1914 	struct nand_chip *chip;
1915 	struct resource cres;
1916 	int chip_cs, mem_region, ret, irq;
1917 	int start_region = 0;
1918 
1919 	nfc = devm_kzalloc(dev, sizeof(*nfc), GFP_KERNEL);
1920 	if (!nfc)
1921 		return -ENOMEM;
1922 
1923 	nfc->dev = dev;
1924 	nand_controller_init(&nfc->base);
1925 	nfc->base.ops = &stm32_fmc2_nfc_controller_ops;
1926 
1927 	nfc->data = of_device_get_match_data(dev);
1928 	if (!nfc->data)
1929 		return -EINVAL;
1930 
1931 	if (nfc->data->set_cdev) {
1932 		ret = nfc->data->set_cdev(nfc);
1933 		if (ret)
1934 			return ret;
1935 	} else {
1936 		nfc->cdev = dev->parent;
1937 	}
1938 
1939 	ret = stm32_fmc2_nfc_parse_dt(nfc);
1940 	if (ret)
1941 		return ret;
1942 
1943 	ret = of_address_to_resource(nfc->cdev->of_node, 0, &cres);
1944 	if (ret)
1945 		return ret;
1946 
1947 	nfc->io_phys_addr = cres.start;
1948 
1949 	nfc->regmap = device_node_to_regmap(nfc->cdev->of_node);
1950 	if (IS_ERR(nfc->regmap))
1951 		return PTR_ERR(nfc->regmap);
1952 
1953 	if (nfc->dev == nfc->cdev)
1954 		start_region = 1;
1955 
1956 	for (chip_cs = 0, mem_region = start_region; chip_cs < nfc->data->max_ncs;
1957 	     chip_cs++, mem_region += 3) {
1958 		if (!(nfc->cs_assigned & BIT(chip_cs)))
1959 			continue;
1960 
1961 		nfc->data_base[chip_cs] = devm_platform_get_and_ioremap_resource(pdev,
1962 						mem_region, &res);
1963 		if (IS_ERR(nfc->data_base[chip_cs]))
1964 			return PTR_ERR(nfc->data_base[chip_cs]);
1965 
1966 		nfc->data_phys_addr[chip_cs] = res->start;
1967 
1968 		nfc->cmd_base[chip_cs] = devm_platform_ioremap_resource(pdev, mem_region + 1);
1969 		if (IS_ERR(nfc->cmd_base[chip_cs]))
1970 			return PTR_ERR(nfc->cmd_base[chip_cs]);
1971 
1972 		nfc->addr_base[chip_cs] = devm_platform_ioremap_resource(pdev, mem_region + 2);
1973 		if (IS_ERR(nfc->addr_base[chip_cs]))
1974 			return PTR_ERR(nfc->addr_base[chip_cs]);
1975 	}
1976 
1977 	irq = platform_get_irq(pdev, 0);
1978 	if (irq < 0)
1979 		return irq;
1980 
1981 	ret = devm_request_irq(dev, irq, stm32_fmc2_nfc_irq, 0,
1982 			       dev_name(dev), nfc);
1983 	if (ret) {
1984 		dev_err(dev, "failed to request irq\n");
1985 		return ret;
1986 	}
1987 
1988 	init_completion(&nfc->complete);
1989 
1990 	nfc->clk = devm_clk_get_enabled(nfc->cdev, NULL);
1991 	if (IS_ERR(nfc->clk)) {
1992 		dev_err(dev, "can not get and enable the clock\n");
1993 		return PTR_ERR(nfc->clk);
1994 	}
1995 
1996 	rstc = devm_reset_control_get(dev, NULL);
1997 	if (IS_ERR(rstc)) {
1998 		ret = PTR_ERR(rstc);
1999 		if (ret == -EPROBE_DEFER)
2000 			return ret;
2001 	} else {
2002 		reset_control_assert(rstc);
2003 		reset_control_deassert(rstc);
2004 	}
2005 
2006 	ret = stm32_fmc2_nfc_dma_setup(nfc);
2007 	if (ret)
2008 		goto err_release_dma;
2009 
2010 	stm32_fmc2_nfc_init(nfc);
2011 
2012 	nand = &nfc->nand;
2013 	chip = &nand->chip;
2014 	mtd = nand_to_mtd(chip);
2015 	mtd->dev.parent = dev;
2016 
2017 	chip->controller = &nfc->base;
2018 	chip->options |= NAND_BUSWIDTH_AUTO | NAND_NO_SUBPAGE_WRITE |
2019 			 NAND_USES_DMA;
2020 
2021 	stm32_fmc2_nfc_wp_disable(nand);
2022 
2023 	/* Scan to find existence of the device */
2024 	ret = nand_scan(chip, nand->ncs);
2025 	if (ret)
2026 		goto err_wp_enable;
2027 
2028 	ret = mtd_device_register(mtd, NULL, 0);
2029 	if (ret)
2030 		goto err_nand_cleanup;
2031 
2032 	platform_set_drvdata(pdev, nfc);
2033 
2034 	return 0;
2035 
2036 err_nand_cleanup:
2037 	nand_cleanup(chip);
2038 
2039 err_wp_enable:
2040 	stm32_fmc2_nfc_wp_enable(nand);
2041 
2042 err_release_dma:
2043 	if (nfc->dma_ecc_ch)
2044 		dma_release_channel(nfc->dma_ecc_ch);
2045 	if (nfc->dma_tx_ch)
2046 		dma_release_channel(nfc->dma_tx_ch);
2047 	if (nfc->dma_rx_ch)
2048 		dma_release_channel(nfc->dma_rx_ch);
2049 
2050 	sg_free_table(&nfc->dma_data_sg);
2051 	sg_free_table(&nfc->dma_ecc_sg);
2052 
2053 	return ret;
2054 }
2055 
2056 static void stm32_fmc2_nfc_remove(struct platform_device *pdev)
2057 {
2058 	struct stm32_fmc2_nfc *nfc = platform_get_drvdata(pdev);
2059 	struct stm32_fmc2_nand *nand = &nfc->nand;
2060 	struct nand_chip *chip = &nand->chip;
2061 	int ret;
2062 
2063 	ret = mtd_device_unregister(nand_to_mtd(chip));
2064 	WARN_ON(ret);
2065 	nand_cleanup(chip);
2066 
2067 	if (nfc->dma_ecc_ch)
2068 		dma_release_channel(nfc->dma_ecc_ch);
2069 	if (nfc->dma_tx_ch)
2070 		dma_release_channel(nfc->dma_tx_ch);
2071 	if (nfc->dma_rx_ch)
2072 		dma_release_channel(nfc->dma_rx_ch);
2073 
2074 	sg_free_table(&nfc->dma_data_sg);
2075 	sg_free_table(&nfc->dma_ecc_sg);
2076 
2077 	stm32_fmc2_nfc_wp_enable(nand);
2078 }
2079 
2080 static int __maybe_unused stm32_fmc2_nfc_suspend(struct device *dev)
2081 {
2082 	struct stm32_fmc2_nfc *nfc = dev_get_drvdata(dev);
2083 	struct stm32_fmc2_nand *nand = &nfc->nand;
2084 
2085 	clk_disable_unprepare(nfc->clk);
2086 
2087 	stm32_fmc2_nfc_wp_enable(nand);
2088 
2089 	pinctrl_pm_select_sleep_state(dev);
2090 
2091 	return 0;
2092 }
2093 
2094 static int __maybe_unused stm32_fmc2_nfc_resume(struct device *dev)
2095 {
2096 	struct stm32_fmc2_nfc *nfc = dev_get_drvdata(dev);
2097 	struct stm32_fmc2_nand *nand = &nfc->nand;
2098 	int chip_cs, ret;
2099 
2100 	pinctrl_pm_select_default_state(dev);
2101 
2102 	ret = clk_prepare_enable(nfc->clk);
2103 	if (ret) {
2104 		dev_err(dev, "can not enable the clock\n");
2105 		return ret;
2106 	}
2107 
2108 	stm32_fmc2_nfc_init(nfc);
2109 
2110 	stm32_fmc2_nfc_wp_disable(nand);
2111 
2112 	for (chip_cs = 0; chip_cs < nfc->data->max_ncs; chip_cs++) {
2113 		if (!(nfc->cs_assigned & BIT(chip_cs)))
2114 			continue;
2115 
2116 		nand_reset(&nand->chip, chip_cs);
2117 	}
2118 
2119 	return 0;
2120 }
2121 
2122 static SIMPLE_DEV_PM_OPS(stm32_fmc2_nfc_pm_ops, stm32_fmc2_nfc_suspend,
2123 			 stm32_fmc2_nfc_resume);
2124 
2125 static const struct stm32_fmc2_nfc_data stm32_fmc2_nfc_mp1_data = {
2126 	.max_ncs = 2,
2127 	.set_cdev = stm32_fmc2_nfc_set_cdev,
2128 };
2129 
2130 static const struct stm32_fmc2_nfc_data stm32_fmc2_nfc_mp25_data = {
2131 	.max_ncs = 4,
2132 };
2133 
2134 static const struct of_device_id stm32_fmc2_nfc_match[] = {
2135 	{
2136 		.compatible = "st,stm32mp15-fmc2",
2137 		.data = &stm32_fmc2_nfc_mp1_data,
2138 	},
2139 	{
2140 		.compatible = "st,stm32mp1-fmc2-nfc",
2141 		.data = &stm32_fmc2_nfc_mp1_data,
2142 	},
2143 	{
2144 		.compatible = "st,stm32mp25-fmc2-nfc",
2145 		.data = &stm32_fmc2_nfc_mp25_data,
2146 	},
2147 	{}
2148 };
2149 MODULE_DEVICE_TABLE(of, stm32_fmc2_nfc_match);
2150 
2151 static struct platform_driver stm32_fmc2_nfc_driver = {
2152 	.probe	= stm32_fmc2_nfc_probe,
2153 	.remove_new = stm32_fmc2_nfc_remove,
2154 	.driver	= {
2155 		.name = "stm32_fmc2_nfc",
2156 		.of_match_table = stm32_fmc2_nfc_match,
2157 		.pm = &stm32_fmc2_nfc_pm_ops,
2158 	},
2159 };
2160 module_platform_driver(stm32_fmc2_nfc_driver);
2161 
2162 MODULE_ALIAS("platform:stm32_fmc2_nfc");
2163 MODULE_AUTHOR("Christophe Kerello <christophe.kerello@st.com>");
2164 MODULE_DESCRIPTION("STMicroelectronics STM32 FMC2 NFC driver");
2165 MODULE_LICENSE("GPL v2");
2166