xref: /linux/drivers/cpufreq/qcom-cpufreq-nvmem.c (revision 55d0969c451159cff86949b38c39171cab962069)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2018, The Linux Foundation. All rights reserved.
4  */
5 
6 /*
7  * In Certain QCOM SoCs like apq8096 and msm8996 that have KRYO processors,
8  * the CPU frequency subset and voltage value of each OPP varies
9  * based on the silicon variant in use. Qualcomm Process Voltage Scaling Tables
10  * defines the voltage and frequency value based on the msm-id in SMEM
11  * and speedbin blown in the efuse combination.
12  * The qcom-cpufreq-nvmem driver reads the msm-id and efuse value from the SoC
13  * to provide the OPP framework with required information.
14  * This is used to determine the voltage and frequency value for each OPP of
15  * operating-points-v2 table when it is parsed by the OPP framework.
16  */
17 
18 #include <linux/cpu.h>
19 #include <linux/err.h>
20 #include <linux/init.h>
21 #include <linux/kernel.h>
22 #include <linux/module.h>
23 #include <linux/nvmem-consumer.h>
24 #include <linux/of.h>
25 #include <linux/platform_device.h>
26 #include <linux/pm.h>
27 #include <linux/pm_domain.h>
28 #include <linux/pm_opp.h>
29 #include <linux/pm_runtime.h>
30 #include <linux/slab.h>
31 #include <linux/soc/qcom/smem.h>
32 
33 #include <dt-bindings/arm/qcom,ids.h>
34 
35 enum ipq806x_versions {
36 	IPQ8062_VERSION = 0,
37 	IPQ8064_VERSION,
38 	IPQ8065_VERSION,
39 };
40 
41 #define IPQ6000_VERSION	BIT(2)
42 
43 enum ipq8074_versions {
44 	IPQ8074_HAWKEYE_VERSION = 0,
45 	IPQ8074_ACORN_VERSION,
46 };
47 
48 struct qcom_cpufreq_drv;
49 
50 struct qcom_cpufreq_match_data {
51 	int (*get_version)(struct device *cpu_dev,
52 			   struct nvmem_cell *speedbin_nvmem,
53 			   char **pvs_name,
54 			   struct qcom_cpufreq_drv *drv);
55 	const char **genpd_names;
56 };
57 
58 struct qcom_cpufreq_drv_cpu {
59 	int opp_token;
60 	struct device **virt_devs;
61 };
62 
63 struct qcom_cpufreq_drv {
64 	u32 versions;
65 	const struct qcom_cpufreq_match_data *data;
66 	struct qcom_cpufreq_drv_cpu cpus[];
67 };
68 
69 static struct platform_device *cpufreq_dt_pdev, *cpufreq_pdev;
70 
71 static int qcom_cpufreq_simple_get_version(struct device *cpu_dev,
72 					   struct nvmem_cell *speedbin_nvmem,
73 					   char **pvs_name,
74 					   struct qcom_cpufreq_drv *drv)
75 {
76 	u8 *speedbin;
77 
78 	*pvs_name = NULL;
79 	speedbin = nvmem_cell_read(speedbin_nvmem, NULL);
80 	if (IS_ERR(speedbin))
81 		return PTR_ERR(speedbin);
82 
83 	dev_dbg(cpu_dev, "speedbin: %d\n", *speedbin);
84 	drv->versions = 1 << *speedbin;
85 	kfree(speedbin);
86 	return 0;
87 }
88 
89 static void get_krait_bin_format_a(struct device *cpu_dev,
90 					  int *speed, int *pvs,
91 					  u8 *buf)
92 {
93 	u32 pte_efuse;
94 
95 	pte_efuse = *((u32 *)buf);
96 
97 	*speed = pte_efuse & 0xf;
98 	if (*speed == 0xf)
99 		*speed = (pte_efuse >> 4) & 0xf;
100 
101 	if (*speed == 0xf) {
102 		*speed = 0;
103 		dev_warn(cpu_dev, "Speed bin: Defaulting to %d\n", *speed);
104 	} else {
105 		dev_dbg(cpu_dev, "Speed bin: %d\n", *speed);
106 	}
107 
108 	*pvs = (pte_efuse >> 10) & 0x7;
109 	if (*pvs == 0x7)
110 		*pvs = (pte_efuse >> 13) & 0x7;
111 
112 	if (*pvs == 0x7) {
113 		*pvs = 0;
114 		dev_warn(cpu_dev, "PVS bin: Defaulting to %d\n", *pvs);
115 	} else {
116 		dev_dbg(cpu_dev, "PVS bin: %d\n", *pvs);
117 	}
118 }
119 
120 static void get_krait_bin_format_b(struct device *cpu_dev,
121 					  int *speed, int *pvs, int *pvs_ver,
122 					  u8 *buf)
123 {
124 	u32 pte_efuse, redundant_sel;
125 
126 	pte_efuse = *((u32 *)buf);
127 	redundant_sel = (pte_efuse >> 24) & 0x7;
128 
129 	*pvs_ver = (pte_efuse >> 4) & 0x3;
130 
131 	switch (redundant_sel) {
132 	case 1:
133 		*pvs = ((pte_efuse >> 28) & 0x8) | ((pte_efuse >> 6) & 0x7);
134 		*speed = (pte_efuse >> 27) & 0xf;
135 		break;
136 	case 2:
137 		*pvs = (pte_efuse >> 27) & 0xf;
138 		*speed = pte_efuse & 0x7;
139 		break;
140 	default:
141 		/* 4 bits of PVS are in efuse register bits 31, 8-6. */
142 		*pvs = ((pte_efuse >> 28) & 0x8) | ((pte_efuse >> 6) & 0x7);
143 		*speed = pte_efuse & 0x7;
144 	}
145 
146 	/* Check SPEED_BIN_BLOW_STATUS */
147 	if (pte_efuse & BIT(3)) {
148 		dev_dbg(cpu_dev, "Speed bin: %d\n", *speed);
149 	} else {
150 		dev_warn(cpu_dev, "Speed bin not set. Defaulting to 0!\n");
151 		*speed = 0;
152 	}
153 
154 	/* Check PVS_BLOW_STATUS */
155 	pte_efuse = *(((u32 *)buf) + 1);
156 	pte_efuse &= BIT(21);
157 	if (pte_efuse) {
158 		dev_dbg(cpu_dev, "PVS bin: %d\n", *pvs);
159 	} else {
160 		dev_warn(cpu_dev, "PVS bin not set. Defaulting to 0!\n");
161 		*pvs = 0;
162 	}
163 
164 	dev_dbg(cpu_dev, "PVS version: %d\n", *pvs_ver);
165 }
166 
167 static int qcom_cpufreq_kryo_name_version(struct device *cpu_dev,
168 					  struct nvmem_cell *speedbin_nvmem,
169 					  char **pvs_name,
170 					  struct qcom_cpufreq_drv *drv)
171 {
172 	size_t len;
173 	u32 msm_id;
174 	u8 *speedbin;
175 	int ret;
176 	*pvs_name = NULL;
177 
178 	ret = qcom_smem_get_soc_id(&msm_id);
179 	if (ret)
180 		return ret;
181 
182 	speedbin = nvmem_cell_read(speedbin_nvmem, &len);
183 	if (IS_ERR(speedbin))
184 		return PTR_ERR(speedbin);
185 
186 	switch (msm_id) {
187 	case QCOM_ID_MSM8996:
188 	case QCOM_ID_APQ8096:
189 	case QCOM_ID_IPQ5332:
190 	case QCOM_ID_IPQ5322:
191 	case QCOM_ID_IPQ5312:
192 	case QCOM_ID_IPQ5302:
193 	case QCOM_ID_IPQ5300:
194 	case QCOM_ID_IPQ5321:
195 	case QCOM_ID_IPQ9514:
196 	case QCOM_ID_IPQ9550:
197 	case QCOM_ID_IPQ9554:
198 	case QCOM_ID_IPQ9570:
199 	case QCOM_ID_IPQ9574:
200 		drv->versions = 1 << (unsigned int)(*speedbin);
201 		break;
202 	case QCOM_ID_MSM8996SG:
203 	case QCOM_ID_APQ8096SG:
204 		drv->versions = 1 << ((unsigned int)(*speedbin) + 4);
205 		break;
206 	default:
207 		BUG();
208 		break;
209 	}
210 
211 	kfree(speedbin);
212 	return 0;
213 }
214 
215 static int qcom_cpufreq_krait_name_version(struct device *cpu_dev,
216 					   struct nvmem_cell *speedbin_nvmem,
217 					   char **pvs_name,
218 					   struct qcom_cpufreq_drv *drv)
219 {
220 	int speed = 0, pvs = 0, pvs_ver = 0;
221 	u8 *speedbin;
222 	size_t len;
223 	int ret = 0;
224 
225 	speedbin = nvmem_cell_read(speedbin_nvmem, &len);
226 
227 	if (IS_ERR(speedbin))
228 		return PTR_ERR(speedbin);
229 
230 	switch (len) {
231 	case 4:
232 		get_krait_bin_format_a(cpu_dev, &speed, &pvs, speedbin);
233 		break;
234 	case 8:
235 		get_krait_bin_format_b(cpu_dev, &speed, &pvs, &pvs_ver,
236 				       speedbin);
237 		break;
238 	default:
239 		dev_err(cpu_dev, "Unable to read nvmem data. Defaulting to 0!\n");
240 		ret = -ENODEV;
241 		goto len_error;
242 	}
243 
244 	snprintf(*pvs_name, sizeof("speedXX-pvsXX-vXX"), "speed%d-pvs%d-v%d",
245 		 speed, pvs, pvs_ver);
246 
247 	drv->versions = (1 << speed);
248 
249 len_error:
250 	kfree(speedbin);
251 	return ret;
252 }
253 
254 static int qcom_cpufreq_ipq8064_name_version(struct device *cpu_dev,
255 					     struct nvmem_cell *speedbin_nvmem,
256 					     char **pvs_name,
257 					     struct qcom_cpufreq_drv *drv)
258 {
259 	int speed = 0, pvs = 0;
260 	int msm_id, ret = 0;
261 	u8 *speedbin;
262 	size_t len;
263 
264 	speedbin = nvmem_cell_read(speedbin_nvmem, &len);
265 	if (IS_ERR(speedbin))
266 		return PTR_ERR(speedbin);
267 
268 	if (len != 4) {
269 		dev_err(cpu_dev, "Unable to read nvmem data. Defaulting to 0!\n");
270 		ret = -ENODEV;
271 		goto exit;
272 	}
273 
274 	get_krait_bin_format_a(cpu_dev, &speed, &pvs, speedbin);
275 
276 	ret = qcom_smem_get_soc_id(&msm_id);
277 	if (ret)
278 		goto exit;
279 
280 	switch (msm_id) {
281 	case QCOM_ID_IPQ8062:
282 		drv->versions = BIT(IPQ8062_VERSION);
283 		break;
284 	case QCOM_ID_IPQ8064:
285 	case QCOM_ID_IPQ8066:
286 	case QCOM_ID_IPQ8068:
287 		drv->versions = BIT(IPQ8064_VERSION);
288 		break;
289 	case QCOM_ID_IPQ8065:
290 	case QCOM_ID_IPQ8069:
291 		drv->versions = BIT(IPQ8065_VERSION);
292 		break;
293 	default:
294 		dev_err(cpu_dev,
295 			"SoC ID %u is not part of IPQ8064 family, limiting to 1.0GHz!\n",
296 			msm_id);
297 		drv->versions = BIT(IPQ8062_VERSION);
298 		break;
299 	}
300 
301 	/* IPQ8064 speed is never fused. Only pvs values are fused. */
302 	snprintf(*pvs_name, sizeof("speed0-pvsXX"), "speed0-pvs%d", pvs);
303 
304 exit:
305 	kfree(speedbin);
306 	return ret;
307 }
308 
309 static int qcom_cpufreq_ipq6018_name_version(struct device *cpu_dev,
310 					     struct nvmem_cell *speedbin_nvmem,
311 					     char **pvs_name,
312 					     struct qcom_cpufreq_drv *drv)
313 {
314 	u32 msm_id;
315 	int ret;
316 	u8 *speedbin;
317 	*pvs_name = NULL;
318 
319 	ret = qcom_smem_get_soc_id(&msm_id);
320 	if (ret)
321 		return ret;
322 
323 	speedbin = nvmem_cell_read(speedbin_nvmem, NULL);
324 	if (IS_ERR(speedbin))
325 		return PTR_ERR(speedbin);
326 
327 	switch (msm_id) {
328 	case QCOM_ID_IPQ6005:
329 	case QCOM_ID_IPQ6010:
330 	case QCOM_ID_IPQ6018:
331 	case QCOM_ID_IPQ6028:
332 		/* Fuse Value    Freq    BIT to set
333 		 * ---------------------------------
334 		 *   2’b0     No Limit     BIT(0)
335 		 *   2’b1     1.5 GHz      BIT(1)
336 		 */
337 		drv->versions = 1 << (unsigned int)(*speedbin);
338 		break;
339 	case QCOM_ID_IPQ6000:
340 		/*
341 		 * IPQ6018 family only has one bit to advertise the CPU
342 		 * speed-bin, but that is not enough for IPQ6000 which
343 		 * is only rated up to 1.2GHz.
344 		 * So for IPQ6000 manually set BIT(2) based on SMEM ID.
345 		 */
346 		drv->versions = IPQ6000_VERSION;
347 		break;
348 	default:
349 		dev_err(cpu_dev,
350 			"SoC ID %u is not part of IPQ6018 family, limiting to 1.2GHz!\n",
351 			msm_id);
352 		drv->versions = IPQ6000_VERSION;
353 		break;
354 	}
355 
356 	kfree(speedbin);
357 	return 0;
358 }
359 
360 static int qcom_cpufreq_ipq8074_name_version(struct device *cpu_dev,
361 					     struct nvmem_cell *speedbin_nvmem,
362 					     char **pvs_name,
363 					     struct qcom_cpufreq_drv *drv)
364 {
365 	u32 msm_id;
366 	int ret;
367 	*pvs_name = NULL;
368 
369 	ret = qcom_smem_get_soc_id(&msm_id);
370 	if (ret)
371 		return ret;
372 
373 	switch (msm_id) {
374 	case QCOM_ID_IPQ8070A:
375 	case QCOM_ID_IPQ8071A:
376 	case QCOM_ID_IPQ8172:
377 	case QCOM_ID_IPQ8173:
378 	case QCOM_ID_IPQ8174:
379 		drv->versions = BIT(IPQ8074_ACORN_VERSION);
380 		break;
381 	case QCOM_ID_IPQ8072A:
382 	case QCOM_ID_IPQ8074A:
383 	case QCOM_ID_IPQ8076A:
384 	case QCOM_ID_IPQ8078A:
385 		drv->versions = BIT(IPQ8074_HAWKEYE_VERSION);
386 		break;
387 	default:
388 		dev_err(cpu_dev,
389 			"SoC ID %u is not part of IPQ8074 family, limiting to 1.4GHz!\n",
390 			msm_id);
391 		drv->versions = BIT(IPQ8074_ACORN_VERSION);
392 		break;
393 	}
394 
395 	return 0;
396 }
397 
398 static const char *generic_genpd_names[] = { "perf", NULL };
399 
400 static const struct qcom_cpufreq_match_data match_data_kryo = {
401 	.get_version = qcom_cpufreq_kryo_name_version,
402 };
403 
404 static const struct qcom_cpufreq_match_data match_data_krait = {
405 	.get_version = qcom_cpufreq_krait_name_version,
406 };
407 
408 static const struct qcom_cpufreq_match_data match_data_msm8909 = {
409 	.get_version = qcom_cpufreq_simple_get_version,
410 	.genpd_names = generic_genpd_names,
411 };
412 
413 static const char *qcs404_genpd_names[] = { "cpr", NULL };
414 
415 static const struct qcom_cpufreq_match_data match_data_qcs404 = {
416 	.genpd_names = qcs404_genpd_names,
417 };
418 
419 static const struct qcom_cpufreq_match_data match_data_ipq6018 = {
420 	.get_version = qcom_cpufreq_ipq6018_name_version,
421 };
422 
423 static const struct qcom_cpufreq_match_data match_data_ipq8064 = {
424 	.get_version = qcom_cpufreq_ipq8064_name_version,
425 };
426 
427 static const struct qcom_cpufreq_match_data match_data_ipq8074 = {
428 	.get_version = qcom_cpufreq_ipq8074_name_version,
429 };
430 
431 static void qcom_cpufreq_suspend_virt_devs(struct qcom_cpufreq_drv *drv, unsigned int cpu)
432 {
433 	const char * const *name = drv->data->genpd_names;
434 	int i;
435 
436 	if (!drv->cpus[cpu].virt_devs)
437 		return;
438 
439 	for (i = 0; *name; i++, name++)
440 		device_set_awake_path(drv->cpus[cpu].virt_devs[i]);
441 }
442 
443 static void qcom_cpufreq_put_virt_devs(struct qcom_cpufreq_drv *drv, unsigned int cpu)
444 {
445 	const char * const *name = drv->data->genpd_names;
446 	int i;
447 
448 	if (!drv->cpus[cpu].virt_devs)
449 		return;
450 
451 	for (i = 0; *name; i++, name++)
452 		pm_runtime_put(drv->cpus[cpu].virt_devs[i]);
453 }
454 
455 static int qcom_cpufreq_probe(struct platform_device *pdev)
456 {
457 	struct qcom_cpufreq_drv *drv;
458 	struct nvmem_cell *speedbin_nvmem;
459 	struct device *cpu_dev;
460 	char pvs_name_buffer[] = "speedXX-pvsXX-vXX";
461 	char *pvs_name = pvs_name_buffer;
462 	unsigned cpu;
463 	const struct of_device_id *match;
464 	int ret;
465 
466 	cpu_dev = get_cpu_device(0);
467 	if (!cpu_dev)
468 		return -ENODEV;
469 
470 	struct device_node *np __free(device_node) =
471 		dev_pm_opp_of_get_opp_desc_node(cpu_dev);
472 	if (!np)
473 		return -ENOENT;
474 
475 	ret = of_device_is_compatible(np, "operating-points-v2-kryo-cpu") ||
476 	      of_device_is_compatible(np, "operating-points-v2-krait-cpu");
477 	if (!ret)
478 		return -ENOENT;
479 
480 	drv = devm_kzalloc(&pdev->dev, struct_size(drv, cpus, num_possible_cpus()),
481 		           GFP_KERNEL);
482 	if (!drv)
483 		return -ENOMEM;
484 
485 	match = pdev->dev.platform_data;
486 	drv->data = match->data;
487 	if (!drv->data)
488 		return -ENODEV;
489 
490 	if (drv->data->get_version) {
491 		speedbin_nvmem = of_nvmem_cell_get(np, NULL);
492 		if (IS_ERR(speedbin_nvmem))
493 			return dev_err_probe(cpu_dev, PTR_ERR(speedbin_nvmem),
494 					     "Could not get nvmem cell\n");
495 
496 		ret = drv->data->get_version(cpu_dev,
497 							speedbin_nvmem, &pvs_name, drv);
498 		if (ret) {
499 			nvmem_cell_put(speedbin_nvmem);
500 			return ret;
501 		}
502 		nvmem_cell_put(speedbin_nvmem);
503 	}
504 
505 	for_each_possible_cpu(cpu) {
506 		struct device **virt_devs = NULL;
507 		struct dev_pm_opp_config config = {
508 			.supported_hw = NULL,
509 		};
510 
511 		cpu_dev = get_cpu_device(cpu);
512 		if (NULL == cpu_dev) {
513 			ret = -ENODEV;
514 			goto free_opp;
515 		}
516 
517 		if (drv->data->get_version) {
518 			config.supported_hw = &drv->versions;
519 			config.supported_hw_count = 1;
520 
521 			if (pvs_name)
522 				config.prop_name = pvs_name;
523 		}
524 
525 		if (drv->data->genpd_names) {
526 			config.genpd_names = drv->data->genpd_names;
527 			config.virt_devs = &virt_devs;
528 		}
529 
530 		if (config.supported_hw || config.genpd_names) {
531 			drv->cpus[cpu].opp_token = dev_pm_opp_set_config(cpu_dev, &config);
532 			if (drv->cpus[cpu].opp_token < 0) {
533 				ret = drv->cpus[cpu].opp_token;
534 				dev_err(cpu_dev, "Failed to set OPP config\n");
535 				goto free_opp;
536 			}
537 		}
538 
539 		if (virt_devs) {
540 			const char * const *name = config.genpd_names;
541 			int i, j;
542 
543 			for (i = 0; *name; i++, name++) {
544 				ret = pm_runtime_resume_and_get(virt_devs[i]);
545 				if (ret) {
546 					dev_err(cpu_dev, "failed to resume %s: %d\n",
547 						*name, ret);
548 
549 					/* Rollback previous PM runtime calls */
550 					name = config.genpd_names;
551 					for (j = 0; *name && j < i; j++, name++)
552 						pm_runtime_put(virt_devs[j]);
553 
554 					goto free_opp;
555 				}
556 			}
557 			drv->cpus[cpu].virt_devs = virt_devs;
558 		}
559 	}
560 
561 	cpufreq_dt_pdev = platform_device_register_simple("cpufreq-dt", -1,
562 							  NULL, 0);
563 	if (!IS_ERR(cpufreq_dt_pdev)) {
564 		platform_set_drvdata(pdev, drv);
565 		return 0;
566 	}
567 
568 	ret = PTR_ERR(cpufreq_dt_pdev);
569 	dev_err(cpu_dev, "Failed to register platform device\n");
570 
571 free_opp:
572 	for_each_possible_cpu(cpu) {
573 		qcom_cpufreq_put_virt_devs(drv, cpu);
574 		dev_pm_opp_clear_config(drv->cpus[cpu].opp_token);
575 	}
576 	return ret;
577 }
578 
579 static void qcom_cpufreq_remove(struct platform_device *pdev)
580 {
581 	struct qcom_cpufreq_drv *drv = platform_get_drvdata(pdev);
582 	unsigned int cpu;
583 
584 	platform_device_unregister(cpufreq_dt_pdev);
585 
586 	for_each_possible_cpu(cpu) {
587 		qcom_cpufreq_put_virt_devs(drv, cpu);
588 		dev_pm_opp_clear_config(drv->cpus[cpu].opp_token);
589 	}
590 }
591 
592 static int qcom_cpufreq_suspend(struct device *dev)
593 {
594 	struct qcom_cpufreq_drv *drv = dev_get_drvdata(dev);
595 	unsigned int cpu;
596 
597 	for_each_possible_cpu(cpu)
598 		qcom_cpufreq_suspend_virt_devs(drv, cpu);
599 
600 	return 0;
601 }
602 
603 static DEFINE_SIMPLE_DEV_PM_OPS(qcom_cpufreq_pm_ops, qcom_cpufreq_suspend, NULL);
604 
605 static struct platform_driver qcom_cpufreq_driver = {
606 	.probe = qcom_cpufreq_probe,
607 	.remove_new = qcom_cpufreq_remove,
608 	.driver = {
609 		.name = "qcom-cpufreq-nvmem",
610 		.pm = pm_sleep_ptr(&qcom_cpufreq_pm_ops),
611 	},
612 };
613 
614 static const struct of_device_id qcom_cpufreq_match_list[] __initconst __maybe_unused = {
615 	{ .compatible = "qcom,apq8096", .data = &match_data_kryo },
616 	{ .compatible = "qcom,msm8909", .data = &match_data_msm8909 },
617 	{ .compatible = "qcom,msm8996", .data = &match_data_kryo },
618 	{ .compatible = "qcom,qcs404", .data = &match_data_qcs404 },
619 	{ .compatible = "qcom,ipq5332", .data = &match_data_kryo },
620 	{ .compatible = "qcom,ipq6018", .data = &match_data_ipq6018 },
621 	{ .compatible = "qcom,ipq8064", .data = &match_data_ipq8064 },
622 	{ .compatible = "qcom,ipq8074", .data = &match_data_ipq8074 },
623 	{ .compatible = "qcom,apq8064", .data = &match_data_krait },
624 	{ .compatible = "qcom,ipq9574", .data = &match_data_kryo },
625 	{ .compatible = "qcom,msm8974", .data = &match_data_krait },
626 	{ .compatible = "qcom,msm8960", .data = &match_data_krait },
627 	{},
628 };
629 MODULE_DEVICE_TABLE(of, qcom_cpufreq_match_list);
630 
631 /*
632  * Since the driver depends on smem and nvmem drivers, which may
633  * return EPROBE_DEFER, all the real activity is done in the probe,
634  * which may be defered as well. The init here is only registering
635  * the driver and the platform device.
636  */
637 static int __init qcom_cpufreq_init(void)
638 {
639 	struct device_node *np __free(device_node) = of_find_node_by_path("/");
640 	const struct of_device_id *match;
641 	int ret;
642 
643 	if (!np)
644 		return -ENODEV;
645 
646 	match = of_match_node(qcom_cpufreq_match_list, np);
647 	if (!match)
648 		return -ENODEV;
649 
650 	ret = platform_driver_register(&qcom_cpufreq_driver);
651 	if (unlikely(ret < 0))
652 		return ret;
653 
654 	cpufreq_pdev = platform_device_register_data(NULL, "qcom-cpufreq-nvmem",
655 						     -1, match, sizeof(*match));
656 	ret = PTR_ERR_OR_ZERO(cpufreq_pdev);
657 	if (0 == ret)
658 		return 0;
659 
660 	platform_driver_unregister(&qcom_cpufreq_driver);
661 	return ret;
662 }
663 module_init(qcom_cpufreq_init);
664 
665 static void __exit qcom_cpufreq_exit(void)
666 {
667 	platform_device_unregister(cpufreq_pdev);
668 	platform_driver_unregister(&qcom_cpufreq_driver);
669 }
670 module_exit(qcom_cpufreq_exit);
671 
672 MODULE_DESCRIPTION("Qualcomm Technologies, Inc. CPUfreq driver");
673 MODULE_LICENSE("GPL v2");
674