xref: /openbmc/linux/drivers/clk/qcom/clk-rpm.c (revision 9470114d)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2016, Linaro Limited
4  * Copyright (c) 2014, The Linux Foundation. All rights reserved.
5  */
6 
7 #include <linux/clk-provider.h>
8 #include <linux/err.h>
9 #include <linux/export.h>
10 #include <linux/init.h>
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/mutex.h>
14 #include <linux/mfd/qcom_rpm.h>
15 #include <linux/of.h>
16 #include <linux/platform_device.h>
17 
18 #include <dt-bindings/mfd/qcom-rpm.h>
19 #include <dt-bindings/clock/qcom,rpmcc.h>
20 
21 #define QCOM_RPM_MISC_CLK_TYPE				0x306b6c63
22 #define QCOM_RPM_SCALING_ENABLE_ID			0x2
23 #define QCOM_RPM_XO_MODE_ON				0x2
24 
25 static const struct clk_parent_data gcc_pxo[] = {
26 	{ .fw_name = "pxo", .name = "pxo_board" },
27 };
28 
29 static const struct clk_parent_data gcc_cxo[] = {
30 	{ .fw_name = "cxo", .name = "cxo_board" },
31 };
32 
33 #define DEFINE_CLK_RPM(_name, r_id)					      \
34 	static struct clk_rpm clk_rpm_##_name##_a_clk;			      \
35 	static struct clk_rpm clk_rpm_##_name##_clk = {			      \
36 		.rpm_clk_id = (r_id),					      \
37 		.peer = &clk_rpm_##_name##_a_clk,			      \
38 		.rate = INT_MAX,					      \
39 		.hw.init = &(struct clk_init_data){			      \
40 			.ops = &clk_rpm_ops,				      \
41 			.name = #_name "_clk",				      \
42 			.parent_data = gcc_pxo,				      \
43 			.num_parents = ARRAY_SIZE(gcc_pxo),		      \
44 		},							      \
45 	};								      \
46 	static struct clk_rpm clk_rpm_##_name##_a_clk = {		      \
47 		.rpm_clk_id = (r_id),					      \
48 		.peer = &clk_rpm_##_name##_clk,				      \
49 		.active_only = true,					      \
50 		.rate = INT_MAX,					      \
51 		.hw.init = &(struct clk_init_data){			      \
52 			.ops = &clk_rpm_ops,				      \
53 			.name = #_name "_a_clk",			      \
54 			.parent_data = gcc_pxo,				      \
55 			.num_parents = ARRAY_SIZE(gcc_pxo),		      \
56 		},							      \
57 	}
58 
59 #define DEFINE_CLK_RPM_XO_BUFFER(_name, offset)				      \
60 	static struct clk_rpm clk_rpm_##_name##_clk = {			      \
61 		.rpm_clk_id = QCOM_RPM_CXO_BUFFERS,			      \
62 		.xo_offset = (offset),					      \
63 		.hw.init = &(struct clk_init_data){			      \
64 			.ops = &clk_rpm_xo_ops,				      \
65 			.name = #_name "_clk",				      \
66 			.parent_data = gcc_cxo,				      \
67 			.num_parents = ARRAY_SIZE(gcc_cxo),		      \
68 		},							      \
69 	}
70 
71 #define DEFINE_CLK_RPM_FIXED(_name, r_id, r)				      \
72 	static struct clk_rpm clk_rpm_##_name##_clk = {			      \
73 		.rpm_clk_id = (r_id),					      \
74 		.rate = (r),						      \
75 		.hw.init = &(struct clk_init_data){			      \
76 			.ops = &clk_rpm_fixed_ops,			      \
77 			.name = #_name "_clk",				      \
78 			.parent_data = gcc_pxo,				      \
79 			.num_parents = ARRAY_SIZE(gcc_pxo),		      \
80 		},							      \
81 	}
82 
83 #define to_clk_rpm(_hw) container_of(_hw, struct clk_rpm, hw)
84 
85 struct rpm_cc;
86 
87 struct clk_rpm {
88 	const int rpm_clk_id;
89 	const int xo_offset;
90 	const bool active_only;
91 	unsigned long rate;
92 	bool enabled;
93 	bool branch;
94 	struct clk_rpm *peer;
95 	struct clk_hw hw;
96 	struct qcom_rpm *rpm;
97 	struct rpm_cc *rpm_cc;
98 };
99 
100 struct rpm_cc {
101 	struct qcom_rpm *rpm;
102 	struct clk_rpm **clks;
103 	size_t num_clks;
104 	u32 xo_buffer_value;
105 	struct mutex xo_lock;
106 };
107 
108 struct rpm_clk_desc {
109 	struct clk_rpm **clks;
110 	size_t num_clks;
111 };
112 
113 static DEFINE_MUTEX(rpm_clk_lock);
114 
115 static int clk_rpm_handoff(struct clk_rpm *r)
116 {
117 	int ret;
118 	u32 value = INT_MAX;
119 
120 	/*
121 	 * The vendor tree simply reads the status for this
122 	 * RPM clock.
123 	 */
124 	if (r->rpm_clk_id == QCOM_RPM_PLL_4 ||
125 		r->rpm_clk_id == QCOM_RPM_CXO_BUFFERS)
126 		return 0;
127 
128 	ret = qcom_rpm_write(r->rpm, QCOM_RPM_ACTIVE_STATE,
129 			     r->rpm_clk_id, &value, 1);
130 	if (ret)
131 		return ret;
132 	ret = qcom_rpm_write(r->rpm, QCOM_RPM_SLEEP_STATE,
133 			     r->rpm_clk_id, &value, 1);
134 	if (ret)
135 		return ret;
136 
137 	return 0;
138 }
139 
140 static int clk_rpm_set_rate_active(struct clk_rpm *r, unsigned long rate)
141 {
142 	u32 value = DIV_ROUND_UP(rate, 1000); /* to kHz */
143 
144 	return qcom_rpm_write(r->rpm, QCOM_RPM_ACTIVE_STATE,
145 			      r->rpm_clk_id, &value, 1);
146 }
147 
148 static int clk_rpm_set_rate_sleep(struct clk_rpm *r, unsigned long rate)
149 {
150 	u32 value = DIV_ROUND_UP(rate, 1000); /* to kHz */
151 
152 	return qcom_rpm_write(r->rpm, QCOM_RPM_SLEEP_STATE,
153 			      r->rpm_clk_id, &value, 1);
154 }
155 
156 static void to_active_sleep(struct clk_rpm *r, unsigned long rate,
157 			    unsigned long *active, unsigned long *sleep)
158 {
159 	*active = rate;
160 
161 	/*
162 	 * Active-only clocks don't care what the rate is during sleep. So,
163 	 * they vote for zero.
164 	 */
165 	if (r->active_only)
166 		*sleep = 0;
167 	else
168 		*sleep = *active;
169 }
170 
171 static int clk_rpm_prepare(struct clk_hw *hw)
172 {
173 	struct clk_rpm *r = to_clk_rpm(hw);
174 	struct clk_rpm *peer = r->peer;
175 	unsigned long this_rate = 0, this_sleep_rate = 0;
176 	unsigned long peer_rate = 0, peer_sleep_rate = 0;
177 	unsigned long active_rate, sleep_rate;
178 	int ret = 0;
179 
180 	mutex_lock(&rpm_clk_lock);
181 
182 	/* Don't send requests to the RPM if the rate has not been set. */
183 	if (!r->rate)
184 		goto out;
185 
186 	to_active_sleep(r, r->rate, &this_rate, &this_sleep_rate);
187 
188 	/* Take peer clock's rate into account only if it's enabled. */
189 	if (peer->enabled)
190 		to_active_sleep(peer, peer->rate,
191 				&peer_rate, &peer_sleep_rate);
192 
193 	active_rate = max(this_rate, peer_rate);
194 
195 	if (r->branch)
196 		active_rate = !!active_rate;
197 
198 	ret = clk_rpm_set_rate_active(r, active_rate);
199 	if (ret)
200 		goto out;
201 
202 	sleep_rate = max(this_sleep_rate, peer_sleep_rate);
203 	if (r->branch)
204 		sleep_rate = !!sleep_rate;
205 
206 	ret = clk_rpm_set_rate_sleep(r, sleep_rate);
207 	if (ret)
208 		/* Undo the active set vote and restore it */
209 		ret = clk_rpm_set_rate_active(r, peer_rate);
210 
211 out:
212 	if (!ret)
213 		r->enabled = true;
214 
215 	mutex_unlock(&rpm_clk_lock);
216 
217 	return ret;
218 }
219 
220 static void clk_rpm_unprepare(struct clk_hw *hw)
221 {
222 	struct clk_rpm *r = to_clk_rpm(hw);
223 	struct clk_rpm *peer = r->peer;
224 	unsigned long peer_rate = 0, peer_sleep_rate = 0;
225 	unsigned long active_rate, sleep_rate;
226 	int ret;
227 
228 	mutex_lock(&rpm_clk_lock);
229 
230 	if (!r->rate)
231 		goto out;
232 
233 	/* Take peer clock's rate into account only if it's enabled. */
234 	if (peer->enabled)
235 		to_active_sleep(peer, peer->rate, &peer_rate,
236 				&peer_sleep_rate);
237 
238 	active_rate = r->branch ? !!peer_rate : peer_rate;
239 	ret = clk_rpm_set_rate_active(r, active_rate);
240 	if (ret)
241 		goto out;
242 
243 	sleep_rate = r->branch ? !!peer_sleep_rate : peer_sleep_rate;
244 	ret = clk_rpm_set_rate_sleep(r, sleep_rate);
245 	if (ret)
246 		goto out;
247 
248 	r->enabled = false;
249 
250 out:
251 	mutex_unlock(&rpm_clk_lock);
252 }
253 
254 static int clk_rpm_xo_prepare(struct clk_hw *hw)
255 {
256 	struct clk_rpm *r = to_clk_rpm(hw);
257 	struct rpm_cc *rcc = r->rpm_cc;
258 	int ret, clk_id = r->rpm_clk_id;
259 	u32 value;
260 
261 	mutex_lock(&rcc->xo_lock);
262 
263 	value = rcc->xo_buffer_value | (QCOM_RPM_XO_MODE_ON << r->xo_offset);
264 	ret = qcom_rpm_write(r->rpm, QCOM_RPM_ACTIVE_STATE, clk_id, &value, 1);
265 	if (!ret) {
266 		r->enabled = true;
267 		rcc->xo_buffer_value = value;
268 	}
269 
270 	mutex_unlock(&rcc->xo_lock);
271 
272 	return ret;
273 }
274 
275 static void clk_rpm_xo_unprepare(struct clk_hw *hw)
276 {
277 	struct clk_rpm *r = to_clk_rpm(hw);
278 	struct rpm_cc *rcc = r->rpm_cc;
279 	int ret, clk_id = r->rpm_clk_id;
280 	u32 value;
281 
282 	mutex_lock(&rcc->xo_lock);
283 
284 	value = rcc->xo_buffer_value & ~(QCOM_RPM_XO_MODE_ON << r->xo_offset);
285 	ret = qcom_rpm_write(r->rpm, QCOM_RPM_ACTIVE_STATE, clk_id, &value, 1);
286 	if (!ret) {
287 		r->enabled = false;
288 		rcc->xo_buffer_value = value;
289 	}
290 
291 	mutex_unlock(&rcc->xo_lock);
292 }
293 
294 static int clk_rpm_fixed_prepare(struct clk_hw *hw)
295 {
296 	struct clk_rpm *r = to_clk_rpm(hw);
297 	u32 value = 1;
298 	int ret;
299 
300 	ret = qcom_rpm_write(r->rpm, QCOM_RPM_ACTIVE_STATE,
301 			     r->rpm_clk_id, &value, 1);
302 	if (!ret)
303 		r->enabled = true;
304 
305 	return ret;
306 }
307 
308 static void clk_rpm_fixed_unprepare(struct clk_hw *hw)
309 {
310 	struct clk_rpm *r = to_clk_rpm(hw);
311 	u32 value = 0;
312 	int ret;
313 
314 	ret = qcom_rpm_write(r->rpm, QCOM_RPM_ACTIVE_STATE,
315 			     r->rpm_clk_id, &value, 1);
316 	if (!ret)
317 		r->enabled = false;
318 }
319 
320 static int clk_rpm_set_rate(struct clk_hw *hw,
321 			    unsigned long rate, unsigned long parent_rate)
322 {
323 	struct clk_rpm *r = to_clk_rpm(hw);
324 	struct clk_rpm *peer = r->peer;
325 	unsigned long active_rate, sleep_rate;
326 	unsigned long this_rate = 0, this_sleep_rate = 0;
327 	unsigned long peer_rate = 0, peer_sleep_rate = 0;
328 	int ret = 0;
329 
330 	mutex_lock(&rpm_clk_lock);
331 
332 	if (!r->enabled)
333 		goto out;
334 
335 	to_active_sleep(r, rate, &this_rate, &this_sleep_rate);
336 
337 	/* Take peer clock's rate into account only if it's enabled. */
338 	if (peer->enabled)
339 		to_active_sleep(peer, peer->rate,
340 				&peer_rate, &peer_sleep_rate);
341 
342 	active_rate = max(this_rate, peer_rate);
343 	ret = clk_rpm_set_rate_active(r, active_rate);
344 	if (ret)
345 		goto out;
346 
347 	sleep_rate = max(this_sleep_rate, peer_sleep_rate);
348 	ret = clk_rpm_set_rate_sleep(r, sleep_rate);
349 	if (ret)
350 		goto out;
351 
352 	r->rate = rate;
353 
354 out:
355 	mutex_unlock(&rpm_clk_lock);
356 
357 	return ret;
358 }
359 
360 static long clk_rpm_round_rate(struct clk_hw *hw, unsigned long rate,
361 			       unsigned long *parent_rate)
362 {
363 	/*
364 	 * RPM handles rate rounding and we don't have a way to
365 	 * know what the rate will be, so just return whatever
366 	 * rate is requested.
367 	 */
368 	return rate;
369 }
370 
371 static unsigned long clk_rpm_recalc_rate(struct clk_hw *hw,
372 					 unsigned long parent_rate)
373 {
374 	struct clk_rpm *r = to_clk_rpm(hw);
375 
376 	/*
377 	 * RPM handles rate rounding and we don't have a way to
378 	 * know what the rate will be, so just return whatever
379 	 * rate was set.
380 	 */
381 	return r->rate;
382 }
383 
384 static const struct clk_ops clk_rpm_xo_ops = {
385 	.prepare	= clk_rpm_xo_prepare,
386 	.unprepare	= clk_rpm_xo_unprepare,
387 };
388 
389 static const struct clk_ops clk_rpm_fixed_ops = {
390 	.prepare	= clk_rpm_fixed_prepare,
391 	.unprepare	= clk_rpm_fixed_unprepare,
392 	.round_rate	= clk_rpm_round_rate,
393 	.recalc_rate	= clk_rpm_recalc_rate,
394 };
395 
396 static const struct clk_ops clk_rpm_ops = {
397 	.prepare	= clk_rpm_prepare,
398 	.unprepare	= clk_rpm_unprepare,
399 	.set_rate	= clk_rpm_set_rate,
400 	.round_rate	= clk_rpm_round_rate,
401 	.recalc_rate	= clk_rpm_recalc_rate,
402 };
403 
404 DEFINE_CLK_RPM(afab, QCOM_RPM_APPS_FABRIC_CLK);
405 DEFINE_CLK_RPM(sfab, QCOM_RPM_SYS_FABRIC_CLK);
406 DEFINE_CLK_RPM(mmfab, QCOM_RPM_MM_FABRIC_CLK);
407 DEFINE_CLK_RPM(daytona, QCOM_RPM_DAYTONA_FABRIC_CLK);
408 DEFINE_CLK_RPM(sfpb, QCOM_RPM_SFPB_CLK);
409 DEFINE_CLK_RPM(cfpb, QCOM_RPM_CFPB_CLK);
410 DEFINE_CLK_RPM(mmfpb, QCOM_RPM_MMFPB_CLK);
411 DEFINE_CLK_RPM(smi, QCOM_RPM_SMI_CLK);
412 DEFINE_CLK_RPM(ebi1, QCOM_RPM_EBI1_CLK);
413 
414 DEFINE_CLK_RPM(qdss, QCOM_RPM_QDSS_CLK);
415 DEFINE_CLK_RPM(nss_fabric_0, QCOM_RPM_NSS_FABRIC_0_CLK);
416 DEFINE_CLK_RPM(nss_fabric_1, QCOM_RPM_NSS_FABRIC_1_CLK);
417 
418 DEFINE_CLK_RPM_FIXED(pll4, QCOM_RPM_PLL_4, 540672000);
419 
420 DEFINE_CLK_RPM_XO_BUFFER(xo_d0, 0);
421 DEFINE_CLK_RPM_XO_BUFFER(xo_d1, 8);
422 DEFINE_CLK_RPM_XO_BUFFER(xo_a0, 16);
423 DEFINE_CLK_RPM_XO_BUFFER(xo_a1, 24);
424 DEFINE_CLK_RPM_XO_BUFFER(xo_a2, 28);
425 
426 static struct clk_rpm *msm8660_clks[] = {
427 	[RPM_APPS_FABRIC_CLK] = &clk_rpm_afab_clk,
428 	[RPM_APPS_FABRIC_A_CLK] = &clk_rpm_afab_a_clk,
429 	[RPM_SYS_FABRIC_CLK] = &clk_rpm_sfab_clk,
430 	[RPM_SYS_FABRIC_A_CLK] = &clk_rpm_sfab_a_clk,
431 	[RPM_MM_FABRIC_CLK] = &clk_rpm_mmfab_clk,
432 	[RPM_MM_FABRIC_A_CLK] = &clk_rpm_mmfab_a_clk,
433 	[RPM_DAYTONA_FABRIC_CLK] = &clk_rpm_daytona_clk,
434 	[RPM_DAYTONA_FABRIC_A_CLK] = &clk_rpm_daytona_a_clk,
435 	[RPM_SFPB_CLK] = &clk_rpm_sfpb_clk,
436 	[RPM_SFPB_A_CLK] = &clk_rpm_sfpb_a_clk,
437 	[RPM_CFPB_CLK] = &clk_rpm_cfpb_clk,
438 	[RPM_CFPB_A_CLK] = &clk_rpm_cfpb_a_clk,
439 	[RPM_MMFPB_CLK] = &clk_rpm_mmfpb_clk,
440 	[RPM_MMFPB_A_CLK] = &clk_rpm_mmfpb_a_clk,
441 	[RPM_SMI_CLK] = &clk_rpm_smi_clk,
442 	[RPM_SMI_A_CLK] = &clk_rpm_smi_a_clk,
443 	[RPM_EBI1_CLK] = &clk_rpm_ebi1_clk,
444 	[RPM_EBI1_A_CLK] = &clk_rpm_ebi1_a_clk,
445 	[RPM_PLL4_CLK] = &clk_rpm_pll4_clk,
446 };
447 
448 static const struct rpm_clk_desc rpm_clk_msm8660 = {
449 	.clks = msm8660_clks,
450 	.num_clks = ARRAY_SIZE(msm8660_clks),
451 };
452 
453 static struct clk_rpm *apq8064_clks[] = {
454 	[RPM_APPS_FABRIC_CLK] = &clk_rpm_afab_clk,
455 	[RPM_APPS_FABRIC_A_CLK] = &clk_rpm_afab_a_clk,
456 	[RPM_CFPB_CLK] = &clk_rpm_cfpb_clk,
457 	[RPM_CFPB_A_CLK] = &clk_rpm_cfpb_a_clk,
458 	[RPM_DAYTONA_FABRIC_CLK] = &clk_rpm_daytona_clk,
459 	[RPM_DAYTONA_FABRIC_A_CLK] = &clk_rpm_daytona_a_clk,
460 	[RPM_EBI1_CLK] = &clk_rpm_ebi1_clk,
461 	[RPM_EBI1_A_CLK] = &clk_rpm_ebi1_a_clk,
462 	[RPM_MM_FABRIC_CLK] = &clk_rpm_mmfab_clk,
463 	[RPM_MM_FABRIC_A_CLK] = &clk_rpm_mmfab_a_clk,
464 	[RPM_MMFPB_CLK] = &clk_rpm_mmfpb_clk,
465 	[RPM_MMFPB_A_CLK] = &clk_rpm_mmfpb_a_clk,
466 	[RPM_SYS_FABRIC_CLK] = &clk_rpm_sfab_clk,
467 	[RPM_SYS_FABRIC_A_CLK] = &clk_rpm_sfab_a_clk,
468 	[RPM_SFPB_CLK] = &clk_rpm_sfpb_clk,
469 	[RPM_SFPB_A_CLK] = &clk_rpm_sfpb_a_clk,
470 	[RPM_QDSS_CLK] = &clk_rpm_qdss_clk,
471 	[RPM_QDSS_A_CLK] = &clk_rpm_qdss_a_clk,
472 	[RPM_XO_D0] = &clk_rpm_xo_d0_clk,
473 	[RPM_XO_D1] = &clk_rpm_xo_d1_clk,
474 	[RPM_XO_A0] = &clk_rpm_xo_a0_clk,
475 	[RPM_XO_A1] = &clk_rpm_xo_a1_clk,
476 	[RPM_XO_A2] = &clk_rpm_xo_a2_clk,
477 };
478 
479 static const struct rpm_clk_desc rpm_clk_apq8064 = {
480 	.clks = apq8064_clks,
481 	.num_clks = ARRAY_SIZE(apq8064_clks),
482 };
483 
484 static struct clk_rpm *ipq806x_clks[] = {
485 	[RPM_APPS_FABRIC_CLK] = &clk_rpm_afab_clk,
486 	[RPM_APPS_FABRIC_A_CLK] = &clk_rpm_afab_a_clk,
487 	[RPM_CFPB_CLK] = &clk_rpm_cfpb_clk,
488 	[RPM_CFPB_A_CLK] = &clk_rpm_cfpb_a_clk,
489 	[RPM_DAYTONA_FABRIC_CLK] = &clk_rpm_daytona_clk,
490 	[RPM_DAYTONA_FABRIC_A_CLK] = &clk_rpm_daytona_a_clk,
491 	[RPM_EBI1_CLK] = &clk_rpm_ebi1_clk,
492 	[RPM_EBI1_A_CLK] = &clk_rpm_ebi1_a_clk,
493 	[RPM_SYS_FABRIC_CLK] = &clk_rpm_sfab_clk,
494 	[RPM_SYS_FABRIC_A_CLK] = &clk_rpm_sfab_a_clk,
495 	[RPM_SFPB_CLK] = &clk_rpm_sfpb_clk,
496 	[RPM_SFPB_A_CLK] = &clk_rpm_sfpb_a_clk,
497 	[RPM_NSS_FABRIC_0_CLK] = &clk_rpm_nss_fabric_0_clk,
498 	[RPM_NSS_FABRIC_0_A_CLK] = &clk_rpm_nss_fabric_0_a_clk,
499 	[RPM_NSS_FABRIC_1_CLK] = &clk_rpm_nss_fabric_1_clk,
500 	[RPM_NSS_FABRIC_1_A_CLK] = &clk_rpm_nss_fabric_1_a_clk,
501 };
502 
503 static const struct rpm_clk_desc rpm_clk_ipq806x = {
504 	.clks = ipq806x_clks,
505 	.num_clks = ARRAY_SIZE(ipq806x_clks),
506 };
507 
508 static const struct of_device_id rpm_clk_match_table[] = {
509 	{ .compatible = "qcom,rpmcc-msm8660", .data = &rpm_clk_msm8660 },
510 	{ .compatible = "qcom,rpmcc-apq8060", .data = &rpm_clk_msm8660 },
511 	{ .compatible = "qcom,rpmcc-apq8064", .data = &rpm_clk_apq8064 },
512 	{ .compatible = "qcom,rpmcc-ipq806x", .data = &rpm_clk_ipq806x },
513 	{ }
514 };
515 MODULE_DEVICE_TABLE(of, rpm_clk_match_table);
516 
517 static struct clk_hw *qcom_rpm_clk_hw_get(struct of_phandle_args *clkspec,
518 					  void *data)
519 {
520 	struct rpm_cc *rcc = data;
521 	unsigned int idx = clkspec->args[0];
522 
523 	if (idx >= rcc->num_clks) {
524 		pr_err("%s: invalid index %u\n", __func__, idx);
525 		return ERR_PTR(-EINVAL);
526 	}
527 
528 	return rcc->clks[idx] ? &rcc->clks[idx]->hw : ERR_PTR(-ENOENT);
529 }
530 
531 static int rpm_clk_probe(struct platform_device *pdev)
532 {
533 	struct rpm_cc *rcc;
534 	int ret;
535 	size_t num_clks, i;
536 	struct qcom_rpm *rpm;
537 	struct clk_rpm **rpm_clks;
538 	const struct rpm_clk_desc *desc;
539 
540 	rpm = dev_get_drvdata(pdev->dev.parent);
541 	if (!rpm) {
542 		dev_err(&pdev->dev, "Unable to retrieve handle to RPM\n");
543 		return -ENODEV;
544 	}
545 
546 	desc = of_device_get_match_data(&pdev->dev);
547 	if (!desc)
548 		return -EINVAL;
549 
550 	rpm_clks = desc->clks;
551 	num_clks = desc->num_clks;
552 
553 	rcc = devm_kzalloc(&pdev->dev, sizeof(*rcc), GFP_KERNEL);
554 	if (!rcc)
555 		return -ENOMEM;
556 
557 	rcc->clks = rpm_clks;
558 	rcc->num_clks = num_clks;
559 	mutex_init(&rcc->xo_lock);
560 
561 	for (i = 0; i < num_clks; i++) {
562 		if (!rpm_clks[i])
563 			continue;
564 
565 		rpm_clks[i]->rpm = rpm;
566 		rpm_clks[i]->rpm_cc = rcc;
567 
568 		ret = clk_rpm_handoff(rpm_clks[i]);
569 		if (ret)
570 			goto err;
571 	}
572 
573 	for (i = 0; i < num_clks; i++) {
574 		if (!rpm_clks[i])
575 			continue;
576 
577 		ret = devm_clk_hw_register(&pdev->dev, &rpm_clks[i]->hw);
578 		if (ret)
579 			goto err;
580 	}
581 
582 	ret = devm_of_clk_add_hw_provider(&pdev->dev, qcom_rpm_clk_hw_get,
583 					  rcc);
584 	if (ret)
585 		goto err;
586 
587 	return 0;
588 err:
589 	dev_err(&pdev->dev, "Error registering RPM Clock driver (%d)\n", ret);
590 	return ret;
591 }
592 
593 static struct platform_driver rpm_clk_driver = {
594 	.driver = {
595 		.name = "qcom-clk-rpm",
596 		.of_match_table = rpm_clk_match_table,
597 	},
598 	.probe = rpm_clk_probe,
599 };
600 
601 static int __init rpm_clk_init(void)
602 {
603 	return platform_driver_register(&rpm_clk_driver);
604 }
605 core_initcall(rpm_clk_init);
606 
607 static void __exit rpm_clk_exit(void)
608 {
609 	platform_driver_unregister(&rpm_clk_driver);
610 }
611 module_exit(rpm_clk_exit);
612 
613 MODULE_DESCRIPTION("Qualcomm RPM Clock Controller Driver");
614 MODULE_LICENSE("GPL v2");
615 MODULE_ALIAS("platform:qcom-clk-rpm");
616