Merge tag 'linux-kselftest-next-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kerne...
[linux-2.6-microblaze.git] / drivers / nvmem / imx-ocotp.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * i.MX6 OCOTP fusebox driver
4  *
5  * Copyright (c) 2015 Pengutronix, Philipp Zabel <p.zabel@pengutronix.de>
6  *
7  * Copyright 2019 NXP
8  *
9  * Based on the barebox ocotp driver,
10  * Copyright (c) 2010 Baruch Siach <baruch@tkos.co.il>,
11  *      Orex Computed Radiography
12  *
13  * Write support based on the fsl_otp driver,
14  * Copyright (C) 2010-2013 Freescale Semiconductor, Inc
15  */
16
17 #include <linux/clk.h>
18 #include <linux/device.h>
19 #include <linux/io.h>
20 #include <linux/module.h>
21 #include <linux/nvmem-provider.h>
22 #include <linux/of.h>
23 #include <linux/of_device.h>
24 #include <linux/platform_device.h>
25 #include <linux/slab.h>
26 #include <linux/delay.h>
27
28 #define IMX_OCOTP_OFFSET_B0W0           0x400 /* Offset from base address of the
29                                                * OTP Bank0 Word0
30                                                */
31 #define IMX_OCOTP_OFFSET_PER_WORD       0x10  /* Offset between the start addr
32                                                * of two consecutive OTP words.
33                                                */
34
35 #define IMX_OCOTP_ADDR_CTRL             0x0000
36 #define IMX_OCOTP_ADDR_CTRL_SET         0x0004
37 #define IMX_OCOTP_ADDR_CTRL_CLR         0x0008
38 #define IMX_OCOTP_ADDR_TIMING           0x0010
39 #define IMX_OCOTP_ADDR_DATA0            0x0020
40 #define IMX_OCOTP_ADDR_DATA1            0x0030
41 #define IMX_OCOTP_ADDR_DATA2            0x0040
42 #define IMX_OCOTP_ADDR_DATA3            0x0050
43
44 #define IMX_OCOTP_BM_CTRL_ADDR          0x000000FF
45 #define IMX_OCOTP_BM_CTRL_BUSY          0x00000100
46 #define IMX_OCOTP_BM_CTRL_ERROR         0x00000200
47 #define IMX_OCOTP_BM_CTRL_REL_SHADOWS   0x00000400
48
49 #define IMX_OCOTP_BM_CTRL_ADDR_8MP              0x000001FF
50 #define IMX_OCOTP_BM_CTRL_BUSY_8MP              0x00000200
51 #define IMX_OCOTP_BM_CTRL_ERROR_8MP             0x00000400
52 #define IMX_OCOTP_BM_CTRL_REL_SHADOWS_8MP       0x00000800
53
54 #define IMX_OCOTP_BM_CTRL_DEFAULT                               \
55         {                                                       \
56                 .bm_addr = IMX_OCOTP_BM_CTRL_ADDR,              \
57                 .bm_busy = IMX_OCOTP_BM_CTRL_BUSY,              \
58                 .bm_error = IMX_OCOTP_BM_CTRL_ERROR,            \
59                 .bm_rel_shadows = IMX_OCOTP_BM_CTRL_REL_SHADOWS,\
60         }
61
62 #define IMX_OCOTP_BM_CTRL_8MP                                   \
63         {                                                       \
64                 .bm_addr = IMX_OCOTP_BM_CTRL_ADDR_8MP,          \
65                 .bm_busy = IMX_OCOTP_BM_CTRL_BUSY_8MP,          \
66                 .bm_error = IMX_OCOTP_BM_CTRL_ERROR_8MP,        \
67                 .bm_rel_shadows = IMX_OCOTP_BM_CTRL_REL_SHADOWS_8MP,\
68         }
69
70 #define TIMING_STROBE_PROG_US           10      /* Min time to blow a fuse */
71 #define TIMING_STROBE_READ_NS           37      /* Min time before read */
72 #define TIMING_RELAX_NS                 17
73 #define DEF_FSOURCE                     1001    /* > 1000 ns */
74 #define DEF_STROBE_PROG                 10000   /* IPG clocks */
75 #define IMX_OCOTP_WR_UNLOCK             0x3E770000
76 #define IMX_OCOTP_READ_LOCKED_VAL       0xBADABADA
77
78 static DEFINE_MUTEX(ocotp_mutex);
79
80 struct ocotp_priv {
81         struct device *dev;
82         struct clk *clk;
83         void __iomem *base;
84         const struct ocotp_params *params;
85         struct nvmem_config *config;
86 };
87
88 struct ocotp_ctrl_reg {
89         u32 bm_addr;
90         u32 bm_busy;
91         u32 bm_error;
92         u32 bm_rel_shadows;
93 };
94
95 struct ocotp_params {
96         unsigned int nregs;
97         unsigned int bank_address_words;
98         void (*set_timing)(struct ocotp_priv *priv);
99         struct ocotp_ctrl_reg ctrl;
100 };
101
102 static int imx_ocotp_wait_for_busy(struct ocotp_priv *priv, u32 flags)
103 {
104         int count;
105         u32 c, mask;
106         u32 bm_ctrl_busy, bm_ctrl_error;
107         void __iomem *base = priv->base;
108
109         bm_ctrl_busy = priv->params->ctrl.bm_busy;
110         bm_ctrl_error = priv->params->ctrl.bm_error;
111
112         mask = bm_ctrl_busy | bm_ctrl_error | flags;
113
114         for (count = 10000; count >= 0; count--) {
115                 c = readl(base + IMX_OCOTP_ADDR_CTRL);
116                 if (!(c & mask))
117                         break;
118                 cpu_relax();
119         }
120
121         if (count < 0) {
122                 /* HW_OCOTP_CTRL[ERROR] will be set under the following
123                  * conditions:
124                  * - A write is performed to a shadow register during a shadow
125                  *   reload (essentially, while HW_OCOTP_CTRL[RELOAD_SHADOWS] is
126                  *   set. In addition, the contents of the shadow register shall
127                  *   not be updated.
128                  * - A write is performed to a shadow register which has been
129                  *   locked.
130                  * - A read is performed to from a shadow register which has
131                  *   been read locked.
132                  * - A program is performed to a fuse word which has been locked
133                  * - A read is performed to from a fuse word which has been read
134                  *   locked.
135                  */
136                 if (c & bm_ctrl_error)
137                         return -EPERM;
138                 return -ETIMEDOUT;
139         }
140
141         return 0;
142 }
143
144 static void imx_ocotp_clr_err_if_set(struct ocotp_priv *priv)
145 {
146         u32 c, bm_ctrl_error;
147         void __iomem *base = priv->base;
148
149         bm_ctrl_error = priv->params->ctrl.bm_error;
150
151         c = readl(base + IMX_OCOTP_ADDR_CTRL);
152         if (!(c & bm_ctrl_error))
153                 return;
154
155         writel(bm_ctrl_error, base + IMX_OCOTP_ADDR_CTRL_CLR);
156 }
157
158 static int imx_ocotp_read(void *context, unsigned int offset,
159                           void *val, size_t bytes)
160 {
161         struct ocotp_priv *priv = context;
162         unsigned int count;
163         u8 *buf, *p;
164         int i, ret;
165         u32 index, num_bytes;
166
167         index = offset >> 2;
168         num_bytes = round_up((offset % 4) + bytes, 4);
169         count = num_bytes >> 2;
170
171         if (count > (priv->params->nregs - index))
172                 count = priv->params->nregs - index;
173
174         p = kzalloc(num_bytes, GFP_KERNEL);
175         if (!p)
176                 return -ENOMEM;
177
178         mutex_lock(&ocotp_mutex);
179
180         buf = p;
181
182         ret = clk_prepare_enable(priv->clk);
183         if (ret < 0) {
184                 mutex_unlock(&ocotp_mutex);
185                 dev_err(priv->dev, "failed to prepare/enable ocotp clk\n");
186                 kfree(p);
187                 return ret;
188         }
189
190         ret = imx_ocotp_wait_for_busy(priv, 0);
191         if (ret < 0) {
192                 dev_err(priv->dev, "timeout during read setup\n");
193                 goto read_end;
194         }
195
196         for (i = index; i < (index + count); i++) {
197                 *(u32 *)buf = readl(priv->base + IMX_OCOTP_OFFSET_B0W0 +
198                                i * IMX_OCOTP_OFFSET_PER_WORD);
199
200                 /* 47.3.1.2
201                  * For "read locked" registers 0xBADABADA will be returned and
202                  * HW_OCOTP_CTRL[ERROR] will be set. It must be cleared by
203                  * software before any new write, read or reload access can be
204                  * issued
205                  */
206                 if (*((u32 *)buf) == IMX_OCOTP_READ_LOCKED_VAL)
207                         imx_ocotp_clr_err_if_set(priv);
208
209                 buf += 4;
210         }
211
212         index = offset % 4;
213         memcpy(val, &p[index], bytes);
214
215 read_end:
216         clk_disable_unprepare(priv->clk);
217         mutex_unlock(&ocotp_mutex);
218
219         kfree(p);
220
221         return ret;
222 }
223
224 static void imx_ocotp_set_imx6_timing(struct ocotp_priv *priv)
225 {
226         unsigned long clk_rate;
227         unsigned long strobe_read, relax, strobe_prog;
228         u32 timing;
229
230         /* 47.3.1.3.1
231          * Program HW_OCOTP_TIMING[STROBE_PROG] and HW_OCOTP_TIMING[RELAX]
232          * fields with timing values to match the current frequency of the
233          * ipg_clk. OTP writes will work at maximum bus frequencies as long
234          * as the HW_OCOTP_TIMING parameters are set correctly.
235          *
236          * Note: there are minimum timings required to ensure an OTP fuse burns
237          * correctly that are independent of the ipg_clk. Those values are not
238          * formally documented anywhere however, working from the minimum
239          * timings given in u-boot we can say:
240          *
241          * - Minimum STROBE_PROG time is 10 microseconds. Intuitively 10
242          *   microseconds feels about right as representative of a minimum time
243          *   to physically burn out a fuse.
244          *
245          * - Minimum STROBE_READ i.e. the time to wait post OTP fuse burn before
246          *   performing another read is 37 nanoseconds
247          *
248          * - Minimum RELAX timing is 17 nanoseconds. This final RELAX minimum
249          *   timing is not entirely clear the documentation says "This
250          *   count value specifies the time to add to all default timing
251          *   parameters other than the Tpgm and Trd. It is given in number
252          *   of ipg_clk periods." where Tpgm and Trd refer to STROBE_PROG
253          *   and STROBE_READ respectively. What the other timing parameters
254          *   are though, is not specified. Experience shows a zero RELAX
255          *   value will mess up a re-load of the shadow registers post OTP
256          *   burn.
257          */
258         clk_rate = clk_get_rate(priv->clk);
259
260         relax = DIV_ROUND_UP(clk_rate * TIMING_RELAX_NS, 1000000000) - 1;
261         strobe_read = DIV_ROUND_UP(clk_rate * TIMING_STROBE_READ_NS,
262                                    1000000000);
263         strobe_read += 2 * (relax + 1) - 1;
264         strobe_prog = DIV_ROUND_CLOSEST(clk_rate * TIMING_STROBE_PROG_US,
265                                         1000000);
266         strobe_prog += 2 * (relax + 1) - 1;
267
268         timing = readl(priv->base + IMX_OCOTP_ADDR_TIMING) & 0x0FC00000;
269         timing |= strobe_prog & 0x00000FFF;
270         timing |= (relax       << 12) & 0x0000F000;
271         timing |= (strobe_read << 16) & 0x003F0000;
272
273         writel(timing, priv->base + IMX_OCOTP_ADDR_TIMING);
274 }
275
276 static void imx_ocotp_set_imx7_timing(struct ocotp_priv *priv)
277 {
278         unsigned long clk_rate;
279         u64 fsource, strobe_prog;
280         u32 timing;
281
282         /* i.MX 7Solo Applications Processor Reference Manual, Rev. 0.1
283          * 6.4.3.3
284          */
285         clk_rate = clk_get_rate(priv->clk);
286         fsource = DIV_ROUND_UP_ULL((u64)clk_rate * DEF_FSOURCE,
287                                    NSEC_PER_SEC) + 1;
288         strobe_prog = DIV_ROUND_CLOSEST_ULL((u64)clk_rate * DEF_STROBE_PROG,
289                                             NSEC_PER_SEC) + 1;
290
291         timing = strobe_prog & 0x00000FFF;
292         timing |= (fsource << 12) & 0x000FF000;
293
294         writel(timing, priv->base + IMX_OCOTP_ADDR_TIMING);
295 }
296
297 static int imx_ocotp_write(void *context, unsigned int offset, void *val,
298                            size_t bytes)
299 {
300         struct ocotp_priv *priv = context;
301         u32 *buf = val;
302         int ret;
303
304         u32 ctrl;
305         u8 waddr;
306         u8 word = 0;
307
308         /* allow only writing one complete OTP word at a time */
309         if ((bytes != priv->config->word_size) ||
310             (offset % priv->config->word_size))
311                 return -EINVAL;
312
313         mutex_lock(&ocotp_mutex);
314
315         ret = clk_prepare_enable(priv->clk);
316         if (ret < 0) {
317                 mutex_unlock(&ocotp_mutex);
318                 dev_err(priv->dev, "failed to prepare/enable ocotp clk\n");
319                 return ret;
320         }
321
322         /* Setup the write timing values */
323         priv->params->set_timing(priv);
324
325         /* 47.3.1.3.2
326          * Check that HW_OCOTP_CTRL[BUSY] and HW_OCOTP_CTRL[ERROR] are clear.
327          * Overlapped accesses are not supported by the controller. Any pending
328          * write or reload must be completed before a write access can be
329          * requested.
330          */
331         ret = imx_ocotp_wait_for_busy(priv, 0);
332         if (ret < 0) {
333                 dev_err(priv->dev, "timeout during timing setup\n");
334                 goto write_end;
335         }
336
337         /* 47.3.1.3.3
338          * Write the requested address to HW_OCOTP_CTRL[ADDR] and program the
339          * unlock code into HW_OCOTP_CTRL[WR_UNLOCK]. This must be programmed
340          * for each write access. The lock code is documented in the register
341          * description. Both the unlock code and address can be written in the
342          * same operation.
343          */
344         if (priv->params->bank_address_words != 0) {
345                 /*
346                  * In banked/i.MX7 mode the OTP register bank goes into waddr
347                  * see i.MX 7Solo Applications Processor Reference Manual, Rev.
348                  * 0.1 section 6.4.3.1
349                  */
350                 offset = offset / priv->config->word_size;
351                 waddr = offset / priv->params->bank_address_words;
352                 word  = offset & (priv->params->bank_address_words - 1);
353         } else {
354                 /*
355                  * Non-banked i.MX6 mode.
356                  * OTP write/read address specifies one of 128 word address
357                  * locations
358                  */
359                 waddr = offset / 4;
360         }
361
362         ctrl = readl(priv->base + IMX_OCOTP_ADDR_CTRL);
363         ctrl &= ~priv->params->ctrl.bm_addr;
364         ctrl |= waddr & priv->params->ctrl.bm_addr;
365         ctrl |= IMX_OCOTP_WR_UNLOCK;
366
367         writel(ctrl, priv->base + IMX_OCOTP_ADDR_CTRL);
368
369         /* 47.3.1.3.4
370          * Write the data to the HW_OCOTP_DATA register. This will automatically
371          * set HW_OCOTP_CTRL[BUSY] and clear HW_OCOTP_CTRL[WR_UNLOCK]. To
372          * protect programming same OTP bit twice, before program OCOTP will
373          * automatically read fuse value in OTP and use read value to mask
374          * program data. The controller will use masked program data to program
375          * a 32-bit word in the OTP per the address in HW_OCOTP_CTRL[ADDR]. Bit
376          * fields with 1's will result in that OTP bit being programmed. Bit
377          * fields with 0's will be ignored. At the same time that the write is
378          * accepted, the controller makes an internal copy of
379          * HW_OCOTP_CTRL[ADDR] which cannot be updated until the next write
380          * sequence is initiated. This copy guarantees that erroneous writes to
381          * HW_OCOTP_CTRL[ADDR] will not affect an active write operation. It
382          * should also be noted that during the programming HW_OCOTP_DATA will
383          * shift right (with zero fill). This shifting is required to program
384          * the OTP serially. During the write operation, HW_OCOTP_DATA cannot be
385          * modified.
386          * Note: on i.MX7 there are four data fields to write for banked write
387          *       with the fuse blowing operation only taking place after data0
388          *       has been written. This is why data0 must always be the last
389          *       register written.
390          */
391         if (priv->params->bank_address_words != 0) {
392                 /* Banked/i.MX7 mode */
393                 switch (word) {
394                 case 0:
395                         writel(0, priv->base + IMX_OCOTP_ADDR_DATA1);
396                         writel(0, priv->base + IMX_OCOTP_ADDR_DATA2);
397                         writel(0, priv->base + IMX_OCOTP_ADDR_DATA3);
398                         writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA0);
399                         break;
400                 case 1:
401                         writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA1);
402                         writel(0, priv->base + IMX_OCOTP_ADDR_DATA2);
403                         writel(0, priv->base + IMX_OCOTP_ADDR_DATA3);
404                         writel(0, priv->base + IMX_OCOTP_ADDR_DATA0);
405                         break;
406                 case 2:
407                         writel(0, priv->base + IMX_OCOTP_ADDR_DATA1);
408                         writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA2);
409                         writel(0, priv->base + IMX_OCOTP_ADDR_DATA3);
410                         writel(0, priv->base + IMX_OCOTP_ADDR_DATA0);
411                         break;
412                 case 3:
413                         writel(0, priv->base + IMX_OCOTP_ADDR_DATA1);
414                         writel(0, priv->base + IMX_OCOTP_ADDR_DATA2);
415                         writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA3);
416                         writel(0, priv->base + IMX_OCOTP_ADDR_DATA0);
417                         break;
418                 }
419         } else {
420                 /* Non-banked i.MX6 mode */
421                 writel(*buf, priv->base + IMX_OCOTP_ADDR_DATA0);
422         }
423
424         /* 47.4.1.4.5
425          * Once complete, the controller will clear BUSY. A write request to a
426          * protected or locked region will result in no OTP access and no
427          * setting of HW_OCOTP_CTRL[BUSY]. In addition HW_OCOTP_CTRL[ERROR] will
428          * be set. It must be cleared by software before any new write access
429          * can be issued.
430          */
431         ret = imx_ocotp_wait_for_busy(priv, 0);
432         if (ret < 0) {
433                 if (ret == -EPERM) {
434                         dev_err(priv->dev, "failed write to locked region");
435                         imx_ocotp_clr_err_if_set(priv);
436                 } else {
437                         dev_err(priv->dev, "timeout during data write\n");
438                 }
439                 goto write_end;
440         }
441
442         /* 47.3.1.4
443          * Write Postamble: Due to internal electrical characteristics of the
444          * OTP during writes, all OTP operations following a write must be
445          * separated by 2 us after the clearing of HW_OCOTP_CTRL_BUSY following
446          * the write.
447          */
448         udelay(2);
449
450         /* reload all shadow registers */
451         writel(priv->params->ctrl.bm_rel_shadows,
452                priv->base + IMX_OCOTP_ADDR_CTRL_SET);
453         ret = imx_ocotp_wait_for_busy(priv,
454                                       priv->params->ctrl.bm_rel_shadows);
455         if (ret < 0)
456                 dev_err(priv->dev, "timeout during shadow register reload\n");
457
458 write_end:
459         clk_disable_unprepare(priv->clk);
460         mutex_unlock(&ocotp_mutex);
461         return ret < 0 ? ret : bytes;
462 }
463
464 static struct nvmem_config imx_ocotp_nvmem_config = {
465         .name = "imx-ocotp",
466         .read_only = false,
467         .word_size = 4,
468         .stride = 1,
469         .reg_read = imx_ocotp_read,
470         .reg_write = imx_ocotp_write,
471 };
472
473 static const struct ocotp_params imx6q_params = {
474         .nregs = 128,
475         .bank_address_words = 0,
476         .set_timing = imx_ocotp_set_imx6_timing,
477         .ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
478 };
479
480 static const struct ocotp_params imx6sl_params = {
481         .nregs = 64,
482         .bank_address_words = 0,
483         .set_timing = imx_ocotp_set_imx6_timing,
484         .ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
485 };
486
487 static const struct ocotp_params imx6sll_params = {
488         .nregs = 128,
489         .bank_address_words = 0,
490         .set_timing = imx_ocotp_set_imx6_timing,
491         .ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
492 };
493
494 static const struct ocotp_params imx6sx_params = {
495         .nregs = 128,
496         .bank_address_words = 0,
497         .set_timing = imx_ocotp_set_imx6_timing,
498         .ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
499 };
500
501 static const struct ocotp_params imx6ul_params = {
502         .nregs = 128,
503         .bank_address_words = 0,
504         .set_timing = imx_ocotp_set_imx6_timing,
505         .ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
506 };
507
508 static const struct ocotp_params imx6ull_params = {
509         .nregs = 64,
510         .bank_address_words = 0,
511         .set_timing = imx_ocotp_set_imx6_timing,
512         .ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
513 };
514
515 static const struct ocotp_params imx7d_params = {
516         .nregs = 64,
517         .bank_address_words = 4,
518         .set_timing = imx_ocotp_set_imx7_timing,
519         .ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
520 };
521
522 static const struct ocotp_params imx7ulp_params = {
523         .nregs = 256,
524         .bank_address_words = 0,
525         .ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
526 };
527
528 static const struct ocotp_params imx8mq_params = {
529         .nregs = 256,
530         .bank_address_words = 0,
531         .set_timing = imx_ocotp_set_imx6_timing,
532         .ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
533 };
534
535 static const struct ocotp_params imx8mm_params = {
536         .nregs = 256,
537         .bank_address_words = 0,
538         .set_timing = imx_ocotp_set_imx6_timing,
539         .ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
540 };
541
542 static const struct ocotp_params imx8mn_params = {
543         .nregs = 256,
544         .bank_address_words = 0,
545         .set_timing = imx_ocotp_set_imx6_timing,
546         .ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
547 };
548
549 static const struct ocotp_params imx8mp_params = {
550         .nregs = 384,
551         .bank_address_words = 0,
552         .set_timing = imx_ocotp_set_imx6_timing,
553         .ctrl = IMX_OCOTP_BM_CTRL_8MP,
554 };
555
556 static const struct of_device_id imx_ocotp_dt_ids[] = {
557         { .compatible = "fsl,imx6q-ocotp",  .data = &imx6q_params },
558         { .compatible = "fsl,imx6sl-ocotp", .data = &imx6sl_params },
559         { .compatible = "fsl,imx6sx-ocotp", .data = &imx6sx_params },
560         { .compatible = "fsl,imx6ul-ocotp", .data = &imx6ul_params },
561         { .compatible = "fsl,imx6ull-ocotp", .data = &imx6ull_params },
562         { .compatible = "fsl,imx7d-ocotp",  .data = &imx7d_params },
563         { .compatible = "fsl,imx6sll-ocotp", .data = &imx6sll_params },
564         { .compatible = "fsl,imx7ulp-ocotp", .data = &imx7ulp_params },
565         { .compatible = "fsl,imx8mq-ocotp", .data = &imx8mq_params },
566         { .compatible = "fsl,imx8mm-ocotp", .data = &imx8mm_params },
567         { .compatible = "fsl,imx8mn-ocotp", .data = &imx8mn_params },
568         { .compatible = "fsl,imx8mp-ocotp", .data = &imx8mp_params },
569         { },
570 };
571 MODULE_DEVICE_TABLE(of, imx_ocotp_dt_ids);
572
573 static int imx_ocotp_probe(struct platform_device *pdev)
574 {
575         struct device *dev = &pdev->dev;
576         struct ocotp_priv *priv;
577         struct nvmem_device *nvmem;
578
579         priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
580         if (!priv)
581                 return -ENOMEM;
582
583         priv->dev = dev;
584
585         priv->base = devm_platform_ioremap_resource(pdev, 0);
586         if (IS_ERR(priv->base))
587                 return PTR_ERR(priv->base);
588
589         priv->clk = devm_clk_get(dev, NULL);
590         if (IS_ERR(priv->clk))
591                 return PTR_ERR(priv->clk);
592
593         priv->params = of_device_get_match_data(&pdev->dev);
594         imx_ocotp_nvmem_config.size = 4 * priv->params->nregs;
595         imx_ocotp_nvmem_config.dev = dev;
596         imx_ocotp_nvmem_config.priv = priv;
597         priv->config = &imx_ocotp_nvmem_config;
598
599         clk_prepare_enable(priv->clk);
600         imx_ocotp_clr_err_if_set(priv);
601         clk_disable_unprepare(priv->clk);
602
603         nvmem = devm_nvmem_register(dev, &imx_ocotp_nvmem_config);
604
605         return PTR_ERR_OR_ZERO(nvmem);
606 }
607
608 static struct platform_driver imx_ocotp_driver = {
609         .probe  = imx_ocotp_probe,
610         .driver = {
611                 .name   = "imx_ocotp",
612                 .of_match_table = imx_ocotp_dt_ids,
613         },
614 };
615 module_platform_driver(imx_ocotp_driver);
616
617 MODULE_AUTHOR("Philipp Zabel <p.zabel@pengutronix.de>");
618 MODULE_DESCRIPTION("i.MX6/i.MX7 OCOTP fuse box driver");
619 MODULE_LICENSE("GPL v2");