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1/*
2 * OMAP3/OMAP4 Voltage Management Routines
3 *
4 * Author: Thara Gopinath <thara@ti.com>
5 *
6 * Copyright (C) 2007 Texas Instruments, Inc.
7 * Rajendra Nayak <rnayak@ti.com>
8 * Lesly A M <x0080970@ti.com>
9 *
10 * Copyright (C) 2008, 2011 Nokia Corporation
11 * Kalle Jokiniemi
12 * Paul Walmsley
13 *
14 * Copyright (C) 2010 Texas Instruments, Inc.
15 * Thara Gopinath <thara@ti.com>
16 *
17 * This program is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License version 2 as
19 * published by the Free Software Foundation.
20 */
21
22#include <linux/delay.h>
23#include <linux/io.h>
24#include <linux/err.h>
25#include <linux/export.h>
26#include <linux/debugfs.h>
27#include <linux/slab.h>
28#include <linux/clk.h>
29
30#include "common.h"
31
32#include "prm-regbits-34xx.h"
33#include "prm-regbits-44xx.h"
34#include "prm44xx.h"
35#include "prcm44xx.h"
36#include "prminst44xx.h"
37#include "control.h"
38
39#include "voltage.h"
40#include "powerdomain.h"
41
42#include "vc.h"
43#include "vp.h"
44
45static LIST_HEAD(voltdm_list);
46
47/* Public functions */
48/**
49 * voltdm_get_voltage() - Gets the current non-auto-compensated voltage
50 * @voltdm: pointer to the voltdm for which current voltage info is needed
51 *
52 * API to get the current non-auto-compensated voltage for a voltage domain.
53 * Returns 0 in case of error else returns the current voltage.
54 */
55unsigned long voltdm_get_voltage(struct voltagedomain *voltdm)
56{
57 if (!voltdm || IS_ERR(voltdm)) {
58 pr_warning("%s: VDD specified does not exist!\n", __func__);
59 return 0;
60 }
61
62 return voltdm->nominal_volt;
63}
64
65/**
66 * voltdm_scale() - API to scale voltage of a particular voltage domain.
67 * @voltdm: pointer to the voltage domain which is to be scaled.
68 * @target_volt: The target voltage of the voltage domain
69 *
70 * This API should be called by the kernel to do the voltage scaling
71 * for a particular voltage domain during DVFS.
72 */
73int voltdm_scale(struct voltagedomain *voltdm,
74 unsigned long target_volt)
75{
76 int ret, i;
77 unsigned long volt = 0;
78
79 if (!voltdm || IS_ERR(voltdm)) {
80 pr_warning("%s: VDD specified does not exist!\n", __func__);
81 return -EINVAL;
82 }
83
84 if (!voltdm->scale) {
85 pr_err("%s: No voltage scale API registered for vdd_%s\n",
86 __func__, voltdm->name);
87 return -ENODATA;
88 }
89
90 /* Adjust voltage to the exact voltage from the OPP table */
91 for (i = 0; voltdm->volt_data[i].volt_nominal != 0; i++) {
92 if (voltdm->volt_data[i].volt_nominal >= target_volt) {
93 volt = voltdm->volt_data[i].volt_nominal;
94 break;
95 }
96 }
97
98 if (!volt) {
99 pr_warning("%s: not scaling. OPP voltage for %lu, not found.\n",
100 __func__, target_volt);
101 return -EINVAL;
102 }
103
104 ret = voltdm->scale(voltdm, volt);
105 if (!ret)
106 voltdm->nominal_volt = volt;
107
108 return ret;
109}
110
111/**
112 * voltdm_reset() - Resets the voltage of a particular voltage domain
113 * to that of the current OPP.
114 * @voltdm: pointer to the voltage domain whose voltage is to be reset.
115 *
116 * This API finds out the correct voltage the voltage domain is supposed
117 * to be at and resets the voltage to that level. Should be used especially
118 * while disabling any voltage compensation modules.
119 */
120void voltdm_reset(struct voltagedomain *voltdm)
121{
122 unsigned long target_volt;
123
124 if (!voltdm || IS_ERR(voltdm)) {
125 pr_warning("%s: VDD specified does not exist!\n", __func__);
126 return;
127 }
128
129 target_volt = voltdm_get_voltage(voltdm);
130 if (!target_volt) {
131 pr_err("%s: unable to find current voltage for vdd_%s\n",
132 __func__, voltdm->name);
133 return;
134 }
135
136 voltdm_scale(voltdm, target_volt);
137}
138
139/**
140 * omap_voltage_get_volttable() - API to get the voltage table associated with a
141 * particular voltage domain.
142 * @voltdm: pointer to the VDD for which the voltage table is required
143 * @volt_data: the voltage table for the particular vdd which is to be
144 * populated by this API
145 *
146 * This API populates the voltage table associated with a VDD into the
147 * passed parameter pointer. Returns the count of distinct voltages
148 * supported by this vdd.
149 *
150 */
151void omap_voltage_get_volttable(struct voltagedomain *voltdm,
152 struct omap_volt_data **volt_data)
153{
154 if (!voltdm || IS_ERR(voltdm)) {
155 pr_warning("%s: VDD specified does not exist!\n", __func__);
156 return;
157 }
158
159 *volt_data = voltdm->volt_data;
160}
161
162/**
163 * omap_voltage_get_voltdata() - API to get the voltage table entry for a
164 * particular voltage
165 * @voltdm: pointer to the VDD whose voltage table has to be searched
166 * @volt: the voltage to be searched in the voltage table
167 *
168 * This API searches through the voltage table for the required voltage
169 * domain and tries to find a matching entry for the passed voltage volt.
170 * If a matching entry is found volt_data is populated with that entry.
171 * This API searches only through the non-compensated voltages int the
172 * voltage table.
173 * Returns pointer to the voltage table entry corresponding to volt on
174 * success. Returns -ENODATA if no voltage table exisits for the passed voltage
175 * domain or if there is no matching entry.
176 */
177struct omap_volt_data *omap_voltage_get_voltdata(struct voltagedomain *voltdm,
178 unsigned long volt)
179{
180 int i;
181
182 if (!voltdm || IS_ERR(voltdm)) {
183 pr_warning("%s: VDD specified does not exist!\n", __func__);
184 return ERR_PTR(-EINVAL);
185 }
186
187 if (!voltdm->volt_data) {
188 pr_warning("%s: voltage table does not exist for vdd_%s\n",
189 __func__, voltdm->name);
190 return ERR_PTR(-ENODATA);
191 }
192
193 for (i = 0; voltdm->volt_data[i].volt_nominal != 0; i++) {
194 if (voltdm->volt_data[i].volt_nominal == volt)
195 return &voltdm->volt_data[i];
196 }
197
198 pr_notice("%s: Unable to match the current voltage with the voltage"
199 "table for vdd_%s\n", __func__, voltdm->name);
200
201 return ERR_PTR(-ENODATA);
202}
203
204/**
205 * omap_voltage_register_pmic() - API to register PMIC specific data
206 * @voltdm: pointer to the VDD for which the PMIC specific data is
207 * to be registered
208 * @pmic: the structure containing pmic info
209 *
210 * This API is to be called by the SOC/PMIC file to specify the
211 * pmic specific info as present in omap_voltdm_pmic structure.
212 */
213int omap_voltage_register_pmic(struct voltagedomain *voltdm,
214 struct omap_voltdm_pmic *pmic)
215{
216 if (!voltdm || IS_ERR(voltdm)) {
217 pr_warning("%s: VDD specified does not exist!\n", __func__);
218 return -EINVAL;
219 }
220
221 voltdm->pmic = pmic;
222
223 return 0;
224}
225
226/**
227 * omap_change_voltscale_method() - API to change the voltage scaling method.
228 * @voltdm: pointer to the VDD whose voltage scaling method
229 * has to be changed.
230 * @voltscale_method: the method to be used for voltage scaling.
231 *
232 * This API can be used by the board files to change the method of voltage
233 * scaling between vpforceupdate and vcbypass. The parameter values are
234 * defined in voltage.h
235 */
236void omap_change_voltscale_method(struct voltagedomain *voltdm,
237 int voltscale_method)
238{
239 if (!voltdm || IS_ERR(voltdm)) {
240 pr_warning("%s: VDD specified does not exist!\n", __func__);
241 return;
242 }
243
244 switch (voltscale_method) {
245 case VOLTSCALE_VPFORCEUPDATE:
246 voltdm->scale = omap_vp_forceupdate_scale;
247 return;
248 case VOLTSCALE_VCBYPASS:
249 voltdm->scale = omap_vc_bypass_scale;
250 return;
251 default:
252 pr_warning("%s: Trying to change the method of voltage scaling"
253 "to an unsupported one!\n", __func__);
254 }
255}
256
257/**
258 * omap_voltage_late_init() - Init the various voltage parameters
259 *
260 * This API is to be called in the later stages of the
261 * system boot to init the voltage controller and
262 * voltage processors.
263 */
264int __init omap_voltage_late_init(void)
265{
266 struct voltagedomain *voltdm;
267
268 if (list_empty(&voltdm_list)) {
269 pr_err("%s: Voltage driver support not added\n",
270 __func__);
271 return -EINVAL;
272 }
273
274 list_for_each_entry(voltdm, &voltdm_list, node) {
275 struct clk *sys_ck;
276
277 if (!voltdm->scalable)
278 continue;
279
280 sys_ck = clk_get(NULL, voltdm->sys_clk.name);
281 if (IS_ERR(sys_ck)) {
282 pr_warning("%s: Could not get sys clk.\n", __func__);
283 return -EINVAL;
284 }
285 voltdm->sys_clk.rate = clk_get_rate(sys_ck);
286 WARN_ON(!voltdm->sys_clk.rate);
287 clk_put(sys_ck);
288
289 if (voltdm->vc) {
290 voltdm->scale = omap_vc_bypass_scale;
291 omap_vc_init_channel(voltdm);
292 }
293
294 if (voltdm->vp) {
295 voltdm->scale = omap_vp_forceupdate_scale;
296 omap_vp_init(voltdm);
297 }
298 }
299
300 return 0;
301}
302
303static struct voltagedomain *_voltdm_lookup(const char *name)
304{
305 struct voltagedomain *voltdm, *temp_voltdm;
306
307 voltdm = NULL;
308
309 list_for_each_entry(temp_voltdm, &voltdm_list, node) {
310 if (!strcmp(name, temp_voltdm->name)) {
311 voltdm = temp_voltdm;
312 break;
313 }
314 }
315
316 return voltdm;
317}
318
319/**
320 * voltdm_add_pwrdm - add a powerdomain to a voltagedomain
321 * @voltdm: struct voltagedomain * to add the powerdomain to
322 * @pwrdm: struct powerdomain * to associate with a voltagedomain
323 *
324 * Associate the powerdomain @pwrdm with a voltagedomain @voltdm. This
325 * enables the use of voltdm_for_each_pwrdm(). Returns -EINVAL if
326 * presented with invalid pointers; -ENOMEM if memory could not be allocated;
327 * or 0 upon success.
328 */
329int voltdm_add_pwrdm(struct voltagedomain *voltdm, struct powerdomain *pwrdm)
330{
331 if (!voltdm || !pwrdm)
332 return -EINVAL;
333
334 pr_debug("voltagedomain: associating powerdomain %s with voltagedomain "
335 "%s\n", pwrdm->name, voltdm->name);
336
337 list_add(&pwrdm->voltdm_node, &voltdm->pwrdm_list);
338
339 return 0;
340}
341
342/**
343 * voltdm_for_each_pwrdm - call function for each pwrdm in a voltdm
344 * @voltdm: struct voltagedomain * to iterate over
345 * @fn: callback function *
346 *
347 * Call the supplied function @fn for each powerdomain in the
348 * voltagedomain @voltdm. Returns -EINVAL if presented with invalid
349 * pointers; or passes along the last return value of the callback
350 * function, which should be 0 for success or anything else to
351 * indicate failure.
352 */
353int voltdm_for_each_pwrdm(struct voltagedomain *voltdm,
354 int (*fn)(struct voltagedomain *voltdm,
355 struct powerdomain *pwrdm))
356{
357 struct powerdomain *pwrdm;
358 int ret = 0;
359
360 if (!fn)
361 return -EINVAL;
362
363 list_for_each_entry(pwrdm, &voltdm->pwrdm_list, voltdm_node)
364 ret = (*fn)(voltdm, pwrdm);
365
366 return ret;
367}
368
369/**
370 * voltdm_for_each - call function on each registered voltagedomain
371 * @fn: callback function *
372 *
373 * Call the supplied function @fn for each registered voltagedomain.
374 * The callback function @fn can return anything but 0 to bail out
375 * early from the iterator. Returns the last return value of the
376 * callback function, which should be 0 for success or anything else
377 * to indicate failure; or -EINVAL if the function pointer is null.
378 */
379int voltdm_for_each(int (*fn)(struct voltagedomain *voltdm, void *user),
380 void *user)
381{
382 struct voltagedomain *temp_voltdm;
383 int ret = 0;
384
385 if (!fn)
386 return -EINVAL;
387
388 list_for_each_entry(temp_voltdm, &voltdm_list, node) {
389 ret = (*fn)(temp_voltdm, user);
390 if (ret)
391 break;
392 }
393
394 return ret;
395}
396
397static int _voltdm_register(struct voltagedomain *voltdm)
398{
399 if (!voltdm || !voltdm->name)
400 return -EINVAL;
401
402 INIT_LIST_HEAD(&voltdm->pwrdm_list);
403 list_add(&voltdm->node, &voltdm_list);
404
405 pr_debug("voltagedomain: registered %s\n", voltdm->name);
406
407 return 0;
408}
409
410/**
411 * voltdm_lookup - look up a voltagedomain by name, return a pointer
412 * @name: name of voltagedomain
413 *
414 * Find a registered voltagedomain by its name @name. Returns a pointer
415 * to the struct voltagedomain if found, or NULL otherwise.
416 */
417struct voltagedomain *voltdm_lookup(const char *name)
418{
419 struct voltagedomain *voltdm ;
420
421 if (!name)
422 return NULL;
423
424 voltdm = _voltdm_lookup(name);
425
426 return voltdm;
427}
428
429/**
430 * voltdm_init - set up the voltagedomain layer
431 * @voltdm_list: array of struct voltagedomain pointers to register
432 *
433 * Loop through the array of voltagedomains @voltdm_list, registering all
434 * that are available on the current CPU. If voltdm_list is supplied
435 * and not null, all of the referenced voltagedomains will be
436 * registered. No return value.
437 */
438void voltdm_init(struct voltagedomain **voltdms)
439{
440 struct voltagedomain **v;
441
442 if (voltdms) {
443 for (v = voltdms; *v; v++)
444 _voltdm_register(*v);
445 }
446}
1/*
2 * OMAP3/OMAP4 Voltage Management Routines
3 *
4 * Author: Thara Gopinath <thara@ti.com>
5 *
6 * Copyright (C) 2007 Texas Instruments, Inc.
7 * Rajendra Nayak <rnayak@ti.com>
8 * Lesly A M <x0080970@ti.com>
9 *
10 * Copyright (C) 2008, 2011 Nokia Corporation
11 * Kalle Jokiniemi
12 * Paul Walmsley
13 *
14 * Copyright (C) 2010 Texas Instruments, Inc.
15 * Thara Gopinath <thara@ti.com>
16 *
17 * This program is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License version 2 as
19 * published by the Free Software Foundation.
20 */
21
22#include <linux/delay.h>
23#include <linux/io.h>
24#include <linux/err.h>
25#include <linux/export.h>
26#include <linux/debugfs.h>
27#include <linux/slab.h>
28#include <linux/clk.h>
29
30#include "common.h"
31
32#include "prm-regbits-34xx.h"
33#include "prm-regbits-44xx.h"
34#include "prm44xx.h"
35#include "prcm44xx.h"
36#include "prminst44xx.h"
37#include "control.h"
38
39#include "voltage.h"
40#include "powerdomain.h"
41
42#include "vc.h"
43#include "vp.h"
44
45static LIST_HEAD(voltdm_list);
46
47/* Public functions */
48/**
49 * voltdm_get_voltage() - Gets the current non-auto-compensated voltage
50 * @voltdm: pointer to the voltdm for which current voltage info is needed
51 *
52 * API to get the current non-auto-compensated voltage for a voltage domain.
53 * Returns 0 in case of error else returns the current voltage.
54 */
55unsigned long voltdm_get_voltage(struct voltagedomain *voltdm)
56{
57 if (!voltdm || IS_ERR(voltdm)) {
58 pr_warning("%s: VDD specified does not exist!\n", __func__);
59 return 0;
60 }
61
62 return voltdm->nominal_volt;
63}
64
65/**
66 * voltdm_scale() - API to scale voltage of a particular voltage domain.
67 * @voltdm: pointer to the voltage domain which is to be scaled.
68 * @target_volt: The target voltage of the voltage domain
69 *
70 * This API should be called by the kernel to do the voltage scaling
71 * for a particular voltage domain during DVFS.
72 */
73int voltdm_scale(struct voltagedomain *voltdm,
74 unsigned long target_volt)
75{
76 int ret, i;
77 unsigned long volt = 0;
78
79 if (!voltdm || IS_ERR(voltdm)) {
80 pr_warning("%s: VDD specified does not exist!\n", __func__);
81 return -EINVAL;
82 }
83
84 if (!voltdm->scale) {
85 pr_err("%s: No voltage scale API registered for vdd_%s\n",
86 __func__, voltdm->name);
87 return -ENODATA;
88 }
89
90 /* Adjust voltage to the exact voltage from the OPP table */
91 for (i = 0; voltdm->volt_data[i].volt_nominal != 0; i++) {
92 if (voltdm->volt_data[i].volt_nominal >= target_volt) {
93 volt = voltdm->volt_data[i].volt_nominal;
94 break;
95 }
96 }
97
98 if (!volt) {
99 pr_warning("%s: not scaling. OPP voltage for %lu, not found.\n",
100 __func__, target_volt);
101 return -EINVAL;
102 }
103
104 ret = voltdm->scale(voltdm, volt);
105 if (!ret)
106 voltdm->nominal_volt = volt;
107
108 return ret;
109}
110
111/**
112 * voltdm_reset() - Resets the voltage of a particular voltage domain
113 * to that of the current OPP.
114 * @voltdm: pointer to the voltage domain whose voltage is to be reset.
115 *
116 * This API finds out the correct voltage the voltage domain is supposed
117 * to be at and resets the voltage to that level. Should be used especially
118 * while disabling any voltage compensation modules.
119 */
120void voltdm_reset(struct voltagedomain *voltdm)
121{
122 unsigned long target_volt;
123
124 if (!voltdm || IS_ERR(voltdm)) {
125 pr_warning("%s: VDD specified does not exist!\n", __func__);
126 return;
127 }
128
129 target_volt = voltdm_get_voltage(voltdm);
130 if (!target_volt) {
131 pr_err("%s: unable to find current voltage for vdd_%s\n",
132 __func__, voltdm->name);
133 return;
134 }
135
136 voltdm_scale(voltdm, target_volt);
137}
138
139/**
140 * omap_voltage_get_volttable() - API to get the voltage table associated with a
141 * particular voltage domain.
142 * @voltdm: pointer to the VDD for which the voltage table is required
143 * @volt_data: the voltage table for the particular vdd which is to be
144 * populated by this API
145 *
146 * This API populates the voltage table associated with a VDD into the
147 * passed parameter pointer. Returns the count of distinct voltages
148 * supported by this vdd.
149 *
150 */
151void omap_voltage_get_volttable(struct voltagedomain *voltdm,
152 struct omap_volt_data **volt_data)
153{
154 if (!voltdm || IS_ERR(voltdm)) {
155 pr_warning("%s: VDD specified does not exist!\n", __func__);
156 return;
157 }
158
159 *volt_data = voltdm->volt_data;
160}
161
162/**
163 * omap_voltage_get_voltdata() - API to get the voltage table entry for a
164 * particular voltage
165 * @voltdm: pointer to the VDD whose voltage table has to be searched
166 * @volt: the voltage to be searched in the voltage table
167 *
168 * This API searches through the voltage table for the required voltage
169 * domain and tries to find a matching entry for the passed voltage volt.
170 * If a matching entry is found volt_data is populated with that entry.
171 * This API searches only through the non-compensated voltages int the
172 * voltage table.
173 * Returns pointer to the voltage table entry corresponding to volt on
174 * success. Returns -ENODATA if no voltage table exisits for the passed voltage
175 * domain or if there is no matching entry.
176 */
177struct omap_volt_data *omap_voltage_get_voltdata(struct voltagedomain *voltdm,
178 unsigned long volt)
179{
180 int i;
181
182 if (!voltdm || IS_ERR(voltdm)) {
183 pr_warning("%s: VDD specified does not exist!\n", __func__);
184 return ERR_PTR(-EINVAL);
185 }
186
187 if (!voltdm->volt_data) {
188 pr_warning("%s: voltage table does not exist for vdd_%s\n",
189 __func__, voltdm->name);
190 return ERR_PTR(-ENODATA);
191 }
192
193 for (i = 0; voltdm->volt_data[i].volt_nominal != 0; i++) {
194 if (voltdm->volt_data[i].volt_nominal == volt)
195 return &voltdm->volt_data[i];
196 }
197
198 pr_notice("%s: Unable to match the current voltage with the voltage table for vdd_%s\n",
199 __func__, voltdm->name);
200
201 return ERR_PTR(-ENODATA);
202}
203
204/**
205 * omap_voltage_register_pmic() - API to register PMIC specific data
206 * @voltdm: pointer to the VDD for which the PMIC specific data is
207 * to be registered
208 * @pmic: the structure containing pmic info
209 *
210 * This API is to be called by the SOC/PMIC file to specify the
211 * pmic specific info as present in omap_voltdm_pmic structure.
212 */
213int omap_voltage_register_pmic(struct voltagedomain *voltdm,
214 struct omap_voltdm_pmic *pmic)
215{
216 if (!voltdm || IS_ERR(voltdm)) {
217 pr_warning("%s: VDD specified does not exist!\n", __func__);
218 return -EINVAL;
219 }
220
221 voltdm->pmic = pmic;
222
223 return 0;
224}
225
226/**
227 * omap_change_voltscale_method() - API to change the voltage scaling method.
228 * @voltdm: pointer to the VDD whose voltage scaling method
229 * has to be changed.
230 * @voltscale_method: the method to be used for voltage scaling.
231 *
232 * This API can be used by the board files to change the method of voltage
233 * scaling between vpforceupdate and vcbypass. The parameter values are
234 * defined in voltage.h
235 */
236void omap_change_voltscale_method(struct voltagedomain *voltdm,
237 int voltscale_method)
238{
239 if (!voltdm || IS_ERR(voltdm)) {
240 pr_warning("%s: VDD specified does not exist!\n", __func__);
241 return;
242 }
243
244 switch (voltscale_method) {
245 case VOLTSCALE_VPFORCEUPDATE:
246 voltdm->scale = omap_vp_forceupdate_scale;
247 return;
248 case VOLTSCALE_VCBYPASS:
249 voltdm->scale = omap_vc_bypass_scale;
250 return;
251 default:
252 pr_warn("%s: Trying to change the method of voltage scaling to an unsupported one!\n",
253 __func__);
254 }
255}
256
257/**
258 * omap_voltage_late_init() - Init the various voltage parameters
259 *
260 * This API is to be called in the later stages of the
261 * system boot to init the voltage controller and
262 * voltage processors.
263 */
264int __init omap_voltage_late_init(void)
265{
266 struct voltagedomain *voltdm;
267
268 if (list_empty(&voltdm_list)) {
269 pr_err("%s: Voltage driver support not added\n",
270 __func__);
271 return -EINVAL;
272 }
273
274 list_for_each_entry(voltdm, &voltdm_list, node) {
275 struct clk *sys_ck;
276
277 if (!voltdm->scalable)
278 continue;
279
280 sys_ck = clk_get(NULL, voltdm->sys_clk.name);
281 if (IS_ERR(sys_ck)) {
282 pr_warning("%s: Could not get sys clk.\n", __func__);
283 return -EINVAL;
284 }
285 voltdm->sys_clk.rate = clk_get_rate(sys_ck);
286 WARN_ON(!voltdm->sys_clk.rate);
287 clk_put(sys_ck);
288
289 if (voltdm->vc) {
290 voltdm->scale = omap_vc_bypass_scale;
291 omap_vc_init_channel(voltdm);
292 }
293
294 if (voltdm->vp) {
295 voltdm->scale = omap_vp_forceupdate_scale;
296 omap_vp_init(voltdm);
297 }
298 }
299
300 return 0;
301}
302
303static struct voltagedomain *_voltdm_lookup(const char *name)
304{
305 struct voltagedomain *voltdm, *temp_voltdm;
306
307 voltdm = NULL;
308
309 list_for_each_entry(temp_voltdm, &voltdm_list, node) {
310 if (!strcmp(name, temp_voltdm->name)) {
311 voltdm = temp_voltdm;
312 break;
313 }
314 }
315
316 return voltdm;
317}
318
319/**
320 * voltdm_add_pwrdm - add a powerdomain to a voltagedomain
321 * @voltdm: struct voltagedomain * to add the powerdomain to
322 * @pwrdm: struct powerdomain * to associate with a voltagedomain
323 *
324 * Associate the powerdomain @pwrdm with a voltagedomain @voltdm. This
325 * enables the use of voltdm_for_each_pwrdm(). Returns -EINVAL if
326 * presented with invalid pointers; -ENOMEM if memory could not be allocated;
327 * or 0 upon success.
328 */
329int voltdm_add_pwrdm(struct voltagedomain *voltdm, struct powerdomain *pwrdm)
330{
331 if (!voltdm || !pwrdm)
332 return -EINVAL;
333
334 pr_debug("voltagedomain: %s: associating powerdomain %s\n",
335 voltdm->name, pwrdm->name);
336
337 list_add(&pwrdm->voltdm_node, &voltdm->pwrdm_list);
338
339 return 0;
340}
341
342/**
343 * voltdm_for_each_pwrdm - call function for each pwrdm in a voltdm
344 * @voltdm: struct voltagedomain * to iterate over
345 * @fn: callback function *
346 *
347 * Call the supplied function @fn for each powerdomain in the
348 * voltagedomain @voltdm. Returns -EINVAL if presented with invalid
349 * pointers; or passes along the last return value of the callback
350 * function, which should be 0 for success or anything else to
351 * indicate failure.
352 */
353int voltdm_for_each_pwrdm(struct voltagedomain *voltdm,
354 int (*fn)(struct voltagedomain *voltdm,
355 struct powerdomain *pwrdm))
356{
357 struct powerdomain *pwrdm;
358 int ret = 0;
359
360 if (!fn)
361 return -EINVAL;
362
363 list_for_each_entry(pwrdm, &voltdm->pwrdm_list, voltdm_node)
364 ret = (*fn)(voltdm, pwrdm);
365
366 return ret;
367}
368
369/**
370 * voltdm_for_each - call function on each registered voltagedomain
371 * @fn: callback function *
372 *
373 * Call the supplied function @fn for each registered voltagedomain.
374 * The callback function @fn can return anything but 0 to bail out
375 * early from the iterator. Returns the last return value of the
376 * callback function, which should be 0 for success or anything else
377 * to indicate failure; or -EINVAL if the function pointer is null.
378 */
379int voltdm_for_each(int (*fn)(struct voltagedomain *voltdm, void *user),
380 void *user)
381{
382 struct voltagedomain *temp_voltdm;
383 int ret = 0;
384
385 if (!fn)
386 return -EINVAL;
387
388 list_for_each_entry(temp_voltdm, &voltdm_list, node) {
389 ret = (*fn)(temp_voltdm, user);
390 if (ret)
391 break;
392 }
393
394 return ret;
395}
396
397static int _voltdm_register(struct voltagedomain *voltdm)
398{
399 if (!voltdm || !voltdm->name)
400 return -EINVAL;
401
402 INIT_LIST_HEAD(&voltdm->pwrdm_list);
403 list_add(&voltdm->node, &voltdm_list);
404
405 pr_debug("voltagedomain: registered %s\n", voltdm->name);
406
407 return 0;
408}
409
410/**
411 * voltdm_lookup - look up a voltagedomain by name, return a pointer
412 * @name: name of voltagedomain
413 *
414 * Find a registered voltagedomain by its name @name. Returns a pointer
415 * to the struct voltagedomain if found, or NULL otherwise.
416 */
417struct voltagedomain *voltdm_lookup(const char *name)
418{
419 struct voltagedomain *voltdm ;
420
421 if (!name)
422 return NULL;
423
424 voltdm = _voltdm_lookup(name);
425
426 return voltdm;
427}
428
429/**
430 * voltdm_init - set up the voltagedomain layer
431 * @voltdm_list: array of struct voltagedomain pointers to register
432 *
433 * Loop through the array of voltagedomains @voltdm_list, registering all
434 * that are available on the current CPU. If voltdm_list is supplied
435 * and not null, all of the referenced voltagedomains will be
436 * registered. No return value.
437 */
438void voltdm_init(struct voltagedomain **voltdms)
439{
440 struct voltagedomain **v;
441
442 if (voltdms) {
443 for (v = voltdms; *v; v++)
444 _voltdm_register(*v);
445 }
446}