Version:  2.0.40 2.2.26 2.4.37 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 4.0 4.1

Linux/drivers/regulator/act8865-regulator.c

  1 /*
  2  * act8865-regulator.c - Voltage regulation for active-semi ACT88xx PMUs
  3  *
  4  * http://www.active-semi.com/products/power-management-units/act88xx/
  5  *
  6  * Copyright (C) 2013 Atmel Corporation
  7  *
  8  * This program is free software; you can redistribute it and/or modify
  9  * it under the terms of the GNU General Public License as published by
 10  * the Free Software Foundation; either version 2 of the License, or
 11  * (at your option) any later version.
 12  *
 13  * This program is distributed in the hope that it will be useful,
 14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
 15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 16  * GNU General Public License for more details.
 17  */
 18 
 19 #include <linux/module.h>
 20 #include <linux/init.h>
 21 #include <linux/i2c.h>
 22 #include <linux/err.h>
 23 #include <linux/platform_device.h>
 24 #include <linux/regulator/driver.h>
 25 #include <linux/regulator/act8865.h>
 26 #include <linux/of.h>
 27 #include <linux/of_device.h>
 28 #include <linux/regulator/of_regulator.h>
 29 #include <linux/regmap.h>
 30 
 31 /*
 32  * ACT8600 Global Register Map.
 33  */
 34 #define ACT8600_SYS_MODE        0x00
 35 #define ACT8600_SYS_CTRL        0x01
 36 #define ACT8600_DCDC1_VSET      0x10
 37 #define ACT8600_DCDC1_CTRL      0x12
 38 #define ACT8600_DCDC2_VSET      0x20
 39 #define ACT8600_DCDC2_CTRL      0x22
 40 #define ACT8600_DCDC3_VSET      0x30
 41 #define ACT8600_DCDC3_CTRL      0x32
 42 #define ACT8600_SUDCDC4_VSET    0x40
 43 #define ACT8600_SUDCDC4_CTRL    0x41
 44 #define ACT8600_LDO5_VSET       0x50
 45 #define ACT8600_LDO5_CTRL       0x51
 46 #define ACT8600_LDO6_VSET       0x60
 47 #define ACT8600_LDO6_CTRL       0x61
 48 #define ACT8600_LDO7_VSET       0x70
 49 #define ACT8600_LDO7_CTRL       0x71
 50 #define ACT8600_LDO8_VSET       0x80
 51 #define ACT8600_LDO8_CTRL       0x81
 52 #define ACT8600_LDO910_CTRL     0x91
 53 #define ACT8600_APCH0           0xA1
 54 #define ACT8600_APCH1           0xA8
 55 #define ACT8600_APCH2           0xA9
 56 #define ACT8600_APCH_STAT       0xAA
 57 #define ACT8600_OTG0            0xB0
 58 #define ACT8600_OTG1            0xB2
 59 
 60 /*
 61  * ACT8846 Global Register Map.
 62  */
 63 #define ACT8846_SYS0            0x00
 64 #define ACT8846_SYS1            0x01
 65 #define ACT8846_REG1_VSET       0x10
 66 #define ACT8846_REG1_CTRL       0x12
 67 #define ACT8846_REG2_VSET0      0x20
 68 #define ACT8846_REG2_VSET1      0x21
 69 #define ACT8846_REG2_CTRL       0x22
 70 #define ACT8846_REG3_VSET0      0x30
 71 #define ACT8846_REG3_VSET1      0x31
 72 #define ACT8846_REG3_CTRL       0x32
 73 #define ACT8846_REG4_VSET0      0x40
 74 #define ACT8846_REG4_VSET1      0x41
 75 #define ACT8846_REG4_CTRL       0x42
 76 #define ACT8846_REG5_VSET       0x50
 77 #define ACT8846_REG5_CTRL       0x51
 78 #define ACT8846_REG6_VSET       0x58
 79 #define ACT8846_REG6_CTRL       0x59
 80 #define ACT8846_REG7_VSET       0x60
 81 #define ACT8846_REG7_CTRL       0x61
 82 #define ACT8846_REG8_VSET       0x68
 83 #define ACT8846_REG8_CTRL       0x69
 84 #define ACT8846_REG9_VSET       0x70
 85 #define ACT8846_REG9_CTRL       0x71
 86 #define ACT8846_REG10_VSET      0x80
 87 #define ACT8846_REG10_CTRL      0x81
 88 #define ACT8846_REG11_VSET      0x90
 89 #define ACT8846_REG11_CTRL      0x91
 90 #define ACT8846_REG12_VSET      0xa0
 91 #define ACT8846_REG12_CTRL      0xa1
 92 #define ACT8846_REG13_CTRL      0xb1
 93 #define ACT8846_GLB_OFF_CTRL    0xc3
 94 #define ACT8846_OFF_SYSMASK     0x18
 95 
 96 /*
 97  * ACT8865 Global Register Map.
 98  */
 99 #define ACT8865_SYS_MODE        0x00
100 #define ACT8865_SYS_CTRL        0x01
101 #define ACT8865_DCDC1_VSET1     0x20
102 #define ACT8865_DCDC1_VSET2     0x21
103 #define ACT8865_DCDC1_CTRL      0x22
104 #define ACT8865_DCDC2_VSET1     0x30
105 #define ACT8865_DCDC2_VSET2     0x31
106 #define ACT8865_DCDC2_CTRL      0x32
107 #define ACT8865_DCDC3_VSET1     0x40
108 #define ACT8865_DCDC3_VSET2     0x41
109 #define ACT8865_DCDC3_CTRL      0x42
110 #define ACT8865_LDO1_VSET       0x50
111 #define ACT8865_LDO1_CTRL       0x51
112 #define ACT8865_LDO2_VSET       0x54
113 #define ACT8865_LDO2_CTRL       0x55
114 #define ACT8865_LDO3_VSET       0x60
115 #define ACT8865_LDO3_CTRL       0x61
116 #define ACT8865_LDO4_VSET       0x64
117 #define ACT8865_LDO4_CTRL       0x65
118 #define ACT8865_MSTROFF         0x20
119 
120 /*
121  * Field Definitions.
122  */
123 #define ACT8865_ENA             0x80    /* ON - [7] */
124 #define ACT8865_VSEL_MASK       0x3F    /* VSET - [5:0] */
125 
126 
127 #define ACT8600_LDO10_ENA               0x40    /* ON - [6] */
128 #define ACT8600_SUDCDC_VSEL_MASK        0xFF    /* SUDCDC VSET - [7:0] */
129 
130 /*
131  * ACT8865 voltage number
132  */
133 #define ACT8865_VOLTAGE_NUM     64
134 #define ACT8600_SUDCDC_VOLTAGE_NUM      255
135 
136 struct act8865 {
137         struct regmap *regmap;
138         int off_reg;
139         int off_mask;
140 };
141 
142 static const struct regmap_config act8865_regmap_config = {
143         .reg_bits = 8,
144         .val_bits = 8,
145 };
146 
147 static const struct regulator_linear_range act8865_voltage_ranges[] = {
148         REGULATOR_LINEAR_RANGE(600000, 0, 23, 25000),
149         REGULATOR_LINEAR_RANGE(1200000, 24, 47, 50000),
150         REGULATOR_LINEAR_RANGE(2400000, 48, 63, 100000),
151 };
152 
153 static const struct regulator_linear_range act8600_sudcdc_voltage_ranges[] = {
154         REGULATOR_LINEAR_RANGE(3000000, 0, 63, 0),
155         REGULATOR_LINEAR_RANGE(3000000, 64, 159, 100000),
156         REGULATOR_LINEAR_RANGE(12600000, 160, 191, 200000),
157         REGULATOR_LINEAR_RANGE(19000000, 191, 255, 400000),
158 };
159 
160 static struct regulator_ops act8865_ops = {
161         .list_voltage           = regulator_list_voltage_linear_range,
162         .map_voltage            = regulator_map_voltage_linear_range,
163         .get_voltage_sel        = regulator_get_voltage_sel_regmap,
164         .set_voltage_sel        = regulator_set_voltage_sel_regmap,
165         .enable                 = regulator_enable_regmap,
166         .disable                = regulator_disable_regmap,
167         .is_enabled             = regulator_is_enabled_regmap,
168 };
169 
170 static struct regulator_ops act8865_ldo_ops = {
171         .enable                 = regulator_enable_regmap,
172         .disable                = regulator_disable_regmap,
173         .is_enabled             = regulator_is_enabled_regmap,
174 };
175 
176 #define ACT88xx_REG(_name, _family, _id, _vsel_reg, _supply)            \
177         [_family##_ID_##_id] = {                                        \
178                 .name                   = _name,                        \
179                 .supply_name            = _supply,                      \
180                 .id                     = _family##_ID_##_id,           \
181                 .type                   = REGULATOR_VOLTAGE,            \
182                 .ops                    = &act8865_ops,                 \
183                 .n_voltages             = ACT8865_VOLTAGE_NUM,          \
184                 .linear_ranges          = act8865_voltage_ranges,       \
185                 .n_linear_ranges        = ARRAY_SIZE(act8865_voltage_ranges), \
186                 .vsel_reg               = _family##_##_id##_##_vsel_reg, \
187                 .vsel_mask              = ACT8865_VSEL_MASK,            \
188                 .enable_reg             = _family##_##_id##_CTRL,       \
189                 .enable_mask            = ACT8865_ENA,                  \
190                 .owner                  = THIS_MODULE,                  \
191         }
192 
193 static const struct regulator_desc act8600_regulators[] = {
194         ACT88xx_REG("DCDC1", ACT8600, DCDC1, VSET, "vp1"),
195         ACT88xx_REG("DCDC2", ACT8600, DCDC2, VSET, "vp2"),
196         ACT88xx_REG("DCDC3", ACT8600, DCDC3, VSET, "vp3"),
197         {
198                 .name = "SUDCDC_REG4",
199                 .id = ACT8600_ID_SUDCDC4,
200                 .ops = &act8865_ops,
201                 .type = REGULATOR_VOLTAGE,
202                 .n_voltages = ACT8600_SUDCDC_VOLTAGE_NUM,
203                 .linear_ranges = act8600_sudcdc_voltage_ranges,
204                 .n_linear_ranges = ARRAY_SIZE(act8600_sudcdc_voltage_ranges),
205                 .vsel_reg = ACT8600_SUDCDC4_VSET,
206                 .vsel_mask = ACT8600_SUDCDC_VSEL_MASK,
207                 .enable_reg = ACT8600_SUDCDC4_CTRL,
208                 .enable_mask = ACT8865_ENA,
209                 .owner = THIS_MODULE,
210         },
211         ACT88xx_REG("LDO5", ACT8600, LDO5, VSET, "inl"),
212         ACT88xx_REG("LDO6", ACT8600, LDO6, VSET, "inl"),
213         ACT88xx_REG("LDO7", ACT8600, LDO7, VSET, "inl"),
214         ACT88xx_REG("LDO8", ACT8600, LDO8, VSET, "inl"),
215         {
216                 .name = "LDO_REG9",
217                 .id = ACT8600_ID_LDO9,
218                 .ops = &act8865_ldo_ops,
219                 .type = REGULATOR_VOLTAGE,
220                 .n_voltages = 1,
221                 .fixed_uV = 1800000,
222                 .enable_reg = ACT8600_LDO910_CTRL,
223                 .enable_mask = ACT8865_ENA,
224                 .owner = THIS_MODULE,
225         },
226         {
227                 .name = "LDO_REG10",
228                 .id = ACT8600_ID_LDO10,
229                 .ops = &act8865_ldo_ops,
230                 .type = REGULATOR_VOLTAGE,
231                 .n_voltages = 1,
232                 .fixed_uV = 1200000,
233                 .enable_reg = ACT8600_LDO910_CTRL,
234                 .enable_mask = ACT8600_LDO10_ENA,
235                 .owner = THIS_MODULE,
236         },
237 };
238 
239 static const struct regulator_desc act8846_regulators[] = {
240         ACT88xx_REG("REG1", ACT8846, REG1, VSET, "vp1"),
241         ACT88xx_REG("REG2", ACT8846, REG2, VSET0, "vp2"),
242         ACT88xx_REG("REG3", ACT8846, REG3, VSET0, "vp3"),
243         ACT88xx_REG("REG4", ACT8846, REG4, VSET0, "vp4"),
244         ACT88xx_REG("REG5", ACT8846, REG5, VSET, "inl1"),
245         ACT88xx_REG("REG6", ACT8846, REG6, VSET, "inl1"),
246         ACT88xx_REG("REG7", ACT8846, REG7, VSET, "inl1"),
247         ACT88xx_REG("REG8", ACT8846, REG8, VSET, "inl2"),
248         ACT88xx_REG("REG9", ACT8846, REG9, VSET, "inl2"),
249         ACT88xx_REG("REG10", ACT8846, REG10, VSET, "inl3"),
250         ACT88xx_REG("REG11", ACT8846, REG11, VSET, "inl3"),
251         ACT88xx_REG("REG12", ACT8846, REG12, VSET, "inl3"),
252 };
253 
254 static const struct regulator_desc act8865_regulators[] = {
255         ACT88xx_REG("DCDC_REG1", ACT8865, DCDC1, VSET1, "vp1"),
256         ACT88xx_REG("DCDC_REG2", ACT8865, DCDC2, VSET1, "vp2"),
257         ACT88xx_REG("DCDC_REG3", ACT8865, DCDC3, VSET1, "vp3"),
258         ACT88xx_REG("LDO_REG1", ACT8865, LDO1, VSET, "inl45"),
259         ACT88xx_REG("LDO_REG2", ACT8865, LDO2, VSET, "inl45"),
260         ACT88xx_REG("LDO_REG3", ACT8865, LDO3, VSET, "inl67"),
261         ACT88xx_REG("LDO_REG4", ACT8865, LDO4, VSET, "inl67"),
262 };
263 
264 #ifdef CONFIG_OF
265 static const struct of_device_id act8865_dt_ids[] = {
266         { .compatible = "active-semi,act8600", .data = (void *)ACT8600 },
267         { .compatible = "active-semi,act8846", .data = (void *)ACT8846 },
268         { .compatible = "active-semi,act8865", .data = (void *)ACT8865 },
269         { }
270 };
271 MODULE_DEVICE_TABLE(of, act8865_dt_ids);
272 
273 static struct of_regulator_match act8846_matches[] = {
274         [ACT8846_ID_REG1]       = { .name = "REG1" },
275         [ACT8846_ID_REG2]       = { .name = "REG2" },
276         [ACT8846_ID_REG3]       = { .name = "REG3" },
277         [ACT8846_ID_REG4]       = { .name = "REG4" },
278         [ACT8846_ID_REG5]       = { .name = "REG5" },
279         [ACT8846_ID_REG6]       = { .name = "REG6" },
280         [ACT8846_ID_REG7]       = { .name = "REG7" },
281         [ACT8846_ID_REG8]       = { .name = "REG8" },
282         [ACT8846_ID_REG9]       = { .name = "REG9" },
283         [ACT8846_ID_REG10]      = { .name = "REG10" },
284         [ACT8846_ID_REG11]      = { .name = "REG11" },
285         [ACT8846_ID_REG12]      = { .name = "REG12" },
286 };
287 
288 static struct of_regulator_match act8865_matches[] = {
289         [ACT8865_ID_DCDC1]      = { .name = "DCDC_REG1"},
290         [ACT8865_ID_DCDC2]      = { .name = "DCDC_REG2"},
291         [ACT8865_ID_DCDC3]      = { .name = "DCDC_REG3"},
292         [ACT8865_ID_LDO1]       = { .name = "LDO_REG1"},
293         [ACT8865_ID_LDO2]       = { .name = "LDO_REG2"},
294         [ACT8865_ID_LDO3]       = { .name = "LDO_REG3"},
295         [ACT8865_ID_LDO4]       = { .name = "LDO_REG4"},
296 };
297 
298 static struct of_regulator_match act8600_matches[] = {
299         [ACT8600_ID_DCDC1]      = { .name = "DCDC_REG1"},
300         [ACT8600_ID_DCDC2]      = { .name = "DCDC_REG2"},
301         [ACT8600_ID_DCDC3]      = { .name = "DCDC_REG3"},
302         [ACT8600_ID_SUDCDC4]    = { .name = "SUDCDC_REG4"},
303         [ACT8600_ID_LDO5]       = { .name = "LDO_REG5"},
304         [ACT8600_ID_LDO6]       = { .name = "LDO_REG6"},
305         [ACT8600_ID_LDO7]       = { .name = "LDO_REG7"},
306         [ACT8600_ID_LDO8]       = { .name = "LDO_REG8"},
307         [ACT8600_ID_LDO9]       = { .name = "LDO_REG9"},
308         [ACT8600_ID_LDO10]      = { .name = "LDO_REG10"},
309 };
310 
311 static int act8865_pdata_from_dt(struct device *dev,
312                                  struct device_node **of_node,
313                                  struct act8865_platform_data *pdata,
314                                  unsigned long type)
315 {
316         int matched, i, num_matches;
317         struct device_node *np;
318         struct act8865_regulator_data *regulator;
319         struct of_regulator_match *matches;
320 
321         np = of_get_child_by_name(dev->of_node, "regulators");
322         if (!np) {
323                 dev_err(dev, "missing 'regulators' subnode in DT\n");
324                 return -EINVAL;
325         }
326 
327         switch (type) {
328         case ACT8600:
329                 matches = act8600_matches;
330                 num_matches = ARRAY_SIZE(act8600_matches);
331                 break;
332         case ACT8846:
333                 matches = act8846_matches;
334                 num_matches = ARRAY_SIZE(act8846_matches);
335                 break;
336         case ACT8865:
337                 matches = act8865_matches;
338                 num_matches = ARRAY_SIZE(act8865_matches);
339                 break;
340         default:
341                 dev_err(dev, "invalid device id %lu\n", type);
342                 return -EINVAL;
343         }
344 
345         matched = of_regulator_match(dev, np, matches, num_matches);
346         of_node_put(np);
347         if (matched <= 0)
348                 return matched;
349 
350         pdata->regulators = devm_kzalloc(dev,
351                                          sizeof(struct act8865_regulator_data) *
352                                          num_matches, GFP_KERNEL);
353         if (!pdata->regulators)
354                 return -ENOMEM;
355 
356         pdata->num_regulators = num_matches;
357         regulator = pdata->regulators;
358 
359         for (i = 0; i < num_matches; i++) {
360                 regulator->id = i;
361                 regulator->name = matches[i].name;
362                 regulator->platform_data = matches[i].init_data;
363                 of_node[i] = matches[i].of_node;
364                 regulator++;
365         }
366 
367         return 0;
368 }
369 #else
370 static inline int act8865_pdata_from_dt(struct device *dev,
371                                         struct device_node **of_node,
372                                         struct act8865_platform_data *pdata,
373                                         unsigned long type)
374 {
375         return 0;
376 }
377 #endif
378 
379 static struct regulator_init_data
380 *act8865_get_init_data(int id, struct act8865_platform_data *pdata)
381 {
382         int i;
383 
384         if (!pdata)
385                 return NULL;
386 
387         for (i = 0; i < pdata->num_regulators; i++) {
388                 if (pdata->regulators[i].id == id)
389                         return pdata->regulators[i].platform_data;
390         }
391 
392         return NULL;
393 }
394 
395 static struct i2c_client *act8865_i2c_client;
396 static void act8865_power_off(void)
397 {
398         struct act8865 *act8865;
399 
400         act8865 = i2c_get_clientdata(act8865_i2c_client);
401         regmap_write(act8865->regmap, act8865->off_reg, act8865->off_mask);
402         while (1);
403 }
404 
405 static int act8865_pmic_probe(struct i2c_client *client,
406                               const struct i2c_device_id *i2c_id)
407 {
408         static const struct regulator_desc *regulators;
409         struct act8865_platform_data pdata_of, *pdata;
410         struct device *dev = &client->dev;
411         struct device_node **of_node;
412         int i, ret, num_regulators;
413         struct act8865 *act8865;
414         unsigned long type;
415         int off_reg, off_mask;
416 
417         pdata = dev_get_platdata(dev);
418 
419         if (dev->of_node && !pdata) {
420                 const struct of_device_id *id;
421 
422                 id = of_match_device(of_match_ptr(act8865_dt_ids), dev);
423                 if (!id)
424                         return -ENODEV;
425 
426                 type = (unsigned long) id->data;
427         } else {
428                 type = i2c_id->driver_data;
429         }
430 
431         switch (type) {
432         case ACT8600:
433                 regulators = act8600_regulators;
434                 num_regulators = ARRAY_SIZE(act8600_regulators);
435                 off_reg = -1;
436                 off_mask = -1;
437                 break;
438         case ACT8846:
439                 regulators = act8846_regulators;
440                 num_regulators = ARRAY_SIZE(act8846_regulators);
441                 off_reg = ACT8846_GLB_OFF_CTRL;
442                 off_mask = ACT8846_OFF_SYSMASK;
443                 break;
444         case ACT8865:
445                 regulators = act8865_regulators;
446                 num_regulators = ARRAY_SIZE(act8865_regulators);
447                 off_reg = ACT8865_SYS_CTRL;
448                 off_mask = ACT8865_MSTROFF;
449                 break;
450         default:
451                 dev_err(dev, "invalid device id %lu\n", type);
452                 return -EINVAL;
453         }
454 
455         of_node = devm_kzalloc(dev, sizeof(struct device_node *) *
456                                num_regulators, GFP_KERNEL);
457         if (!of_node)
458                 return -ENOMEM;
459 
460         if (dev->of_node && !pdata) {
461                 ret = act8865_pdata_from_dt(dev, of_node, &pdata_of, type);
462                 if (ret < 0)
463                         return ret;
464 
465                 pdata = &pdata_of;
466         }
467 
468         if (pdata->num_regulators > num_regulators) {
469                 dev_err(dev, "too many regulators: %d\n",
470                         pdata->num_regulators);
471                 return -EINVAL;
472         }
473 
474         act8865 = devm_kzalloc(dev, sizeof(struct act8865), GFP_KERNEL);
475         if (!act8865)
476                 return -ENOMEM;
477 
478         act8865->regmap = devm_regmap_init_i2c(client, &act8865_regmap_config);
479         if (IS_ERR(act8865->regmap)) {
480                 ret = PTR_ERR(act8865->regmap);
481                 dev_err(&client->dev, "Failed to allocate register map: %d\n",
482                         ret);
483                 return ret;
484         }
485 
486         if (of_device_is_system_power_controller(dev->of_node)) {
487                 if (!pm_power_off && (off_reg > 0)) {
488                         act8865_i2c_client = client;
489                         act8865->off_reg = off_reg;
490                         act8865->off_mask = off_mask;
491                         pm_power_off = act8865_power_off;
492                 } else {
493                         dev_err(dev, "Failed to set poweroff capability, already defined\n");
494                 }
495         }
496 
497         /* Finally register devices */
498         for (i = 0; i < num_regulators; i++) {
499                 const struct regulator_desc *desc = &regulators[i];
500                 struct regulator_config config = { };
501                 struct regulator_dev *rdev;
502 
503                 config.dev = dev;
504                 config.init_data = act8865_get_init_data(desc->id, pdata);
505                 config.of_node = of_node[i];
506                 config.driver_data = act8865;
507                 config.regmap = act8865->regmap;
508 
509                 rdev = devm_regulator_register(&client->dev, desc, &config);
510                 if (IS_ERR(rdev)) {
511                         dev_err(dev, "failed to register %s\n", desc->name);
512                         return PTR_ERR(rdev);
513                 }
514         }
515 
516         i2c_set_clientdata(client, act8865);
517         devm_kfree(dev, of_node);
518 
519         return 0;
520 }
521 
522 static const struct i2c_device_id act8865_ids[] = {
523         { .name = "act8600", .driver_data = ACT8600 },
524         { .name = "act8846", .driver_data = ACT8846 },
525         { .name = "act8865", .driver_data = ACT8865 },
526         { },
527 };
528 MODULE_DEVICE_TABLE(i2c, act8865_ids);
529 
530 static struct i2c_driver act8865_pmic_driver = {
531         .driver = {
532                 .name   = "act8865",
533                 .owner  = THIS_MODULE,
534         },
535         .probe          = act8865_pmic_probe,
536         .id_table       = act8865_ids,
537 };
538 
539 module_i2c_driver(act8865_pmic_driver);
540 
541 MODULE_DESCRIPTION("active-semi act88xx voltage regulator driver");
542 MODULE_AUTHOR("Wenyou Yang <wenyou.yang@atmel.com>");
543 MODULE_LICENSE("GPL v2");
544 

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