Merge tag 'for-linus' of git://linux-c6x.org/git/projects/linux-c6x-upstreaming
[pandora-kernel.git] / drivers / regulator / tps62360-regulator.c
1 /*
2  * tps62360.c -- TI tps62360
3  *
4  * Driver for processor core supply tps62360, tps62361B, tps62362 and tps62363.
5  *
6  * Copyright (c) 2012, NVIDIA Corporation.
7  *
8  * Author: Laxman Dewangan <ldewangan@nvidia.com>
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public License as
12  * published by the Free Software Foundation version 2.
13  *
14  * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
15  * whether express or implied; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
22  * 02111-1307, USA
23  */
24
25 #include <linux/kernel.h>
26 #include <linux/module.h>
27 #include <linux/init.h>
28 #include <linux/err.h>
29 #include <linux/of.h>
30 #include <linux/of_device.h>
31 #include <linux/of_gpio.h>
32 #include <linux/regulator/of_regulator.h>
33 #include <linux/platform_device.h>
34 #include <linux/regulator/driver.h>
35 #include <linux/regulator/machine.h>
36 #include <linux/regulator/tps62360.h>
37 #include <linux/gpio.h>
38 #include <linux/i2c.h>
39 #include <linux/slab.h>
40 #include <linux/regmap.h>
41
42 /* Register definitions */
43 #define REG_VSET0               0
44 #define REG_VSET1               1
45 #define REG_VSET2               2
46 #define REG_VSET3               3
47 #define REG_CONTROL             4
48 #define REG_TEMP                5
49 #define REG_RAMPCTRL            6
50 #define REG_CHIPID              8
51
52 #define FORCE_PWM_ENABLE        BIT(7)
53
54 enum chips {TPS62360, TPS62361, TPS62362, TPS62363};
55
56 #define TPS62360_BASE_VOLTAGE   770000
57 #define TPS62360_N_VOLTAGES     64
58
59 #define TPS62361_BASE_VOLTAGE   500000
60 #define TPS62361_N_VOLTAGES     128
61
62 /* tps 62360 chip information */
63 struct tps62360_chip {
64         struct device *dev;
65         struct regulator_desc desc;
66         struct regulator_dev *rdev;
67         struct regmap *regmap;
68         int vsel0_gpio;
69         int vsel1_gpio;
70         u8 voltage_reg_mask;
71         bool en_internal_pulldn;
72         bool en_discharge;
73         bool valid_gpios;
74         int lru_index[4];
75         int curr_vset_vsel[4];
76         int curr_vset_id;
77 };
78
79 /*
80  * find_voltage_set_register: Find new voltage configuration register
81  * (VSET) id.
82  * The finding of the new VSET register will be based on the LRU mechanism.
83  * Each VSET register will have different voltage configured . This
84  * Function will look if any of the VSET register have requested voltage set
85  * or not.
86  *     - If it is already there then it will make that register as most
87  *       recently used and return as found so that caller need not to set
88  *       the VSET register but need to set the proper gpios to select this
89  *       VSET register.
90  *     - If requested voltage is not found then it will use the least
91  *       recently mechanism to get new VSET register for new configuration
92  *       and will return not_found so that caller need to set new VSET
93  *       register and then gpios (both).
94  */
95 static bool find_voltage_set_register(struct tps62360_chip *tps,
96                 int req_vsel, int *vset_reg_id)
97 {
98         int i;
99         bool found = false;
100         int new_vset_reg = tps->lru_index[3];
101         int found_index = 3;
102
103         for (i = 0; i < 4; ++i) {
104                 if (tps->curr_vset_vsel[tps->lru_index[i]] == req_vsel) {
105                         new_vset_reg = tps->lru_index[i];
106                         found_index = i;
107                         found = true;
108                         goto update_lru_index;
109                 }
110         }
111
112 update_lru_index:
113         for (i = found_index; i > 0; i--)
114                 tps->lru_index[i] = tps->lru_index[i - 1];
115
116         tps->lru_index[0] = new_vset_reg;
117         *vset_reg_id = new_vset_reg;
118         return found;
119 }
120
121 static int tps62360_dcdc_get_voltage_sel(struct regulator_dev *dev)
122 {
123         struct tps62360_chip *tps = rdev_get_drvdata(dev);
124         int vsel;
125         unsigned int data;
126         int ret;
127
128         ret = regmap_read(tps->regmap, REG_VSET0 + tps->curr_vset_id, &data);
129         if (ret < 0) {
130                 dev_err(tps->dev, "%s(): register %d read failed with err %d\n",
131                         __func__, REG_VSET0 + tps->curr_vset_id, ret);
132                 return ret;
133         }
134         vsel = (int)data & tps->voltage_reg_mask;
135         return vsel;
136 }
137
138 static int tps62360_dcdc_set_voltage_sel(struct regulator_dev *dev,
139                                          unsigned selector)
140 {
141         struct tps62360_chip *tps = rdev_get_drvdata(dev);
142         int ret;
143         bool found = false;
144         int new_vset_id = tps->curr_vset_id;
145
146         /*
147          * If gpios are available to select the VSET register then least
148          * recently used register for new configuration.
149          */
150         if (tps->valid_gpios)
151                 found = find_voltage_set_register(tps, selector, &new_vset_id);
152
153         if (!found) {
154                 ret = regmap_update_bits(tps->regmap, REG_VSET0 + new_vset_id,
155                                 tps->voltage_reg_mask, selector);
156                 if (ret < 0) {
157                         dev_err(tps->dev,
158                                 "%s(): register %d update failed with err %d\n",
159                                  __func__, REG_VSET0 + new_vset_id, ret);
160                         return ret;
161                 }
162                 tps->curr_vset_id = new_vset_id;
163                 tps->curr_vset_vsel[new_vset_id] = selector;
164         }
165
166         /* Select proper VSET register vio gpios */
167         if (tps->valid_gpios) {
168                 gpio_set_value_cansleep(tps->vsel0_gpio, new_vset_id & 0x1);
169                 gpio_set_value_cansleep(tps->vsel1_gpio,
170                                         (new_vset_id >> 1) & 0x1);
171         }
172         return 0;
173 }
174
175 static int tps62360_set_mode(struct regulator_dev *rdev, unsigned int mode)
176 {
177         struct tps62360_chip *tps = rdev_get_drvdata(rdev);
178         int i;
179         int val;
180         int ret;
181
182         /* Enable force PWM mode in FAST mode only. */
183         switch (mode) {
184         case REGULATOR_MODE_FAST:
185                 val = FORCE_PWM_ENABLE;
186                 break;
187
188         case REGULATOR_MODE_NORMAL:
189                 val = 0;
190                 break;
191
192         default:
193                 return -EINVAL;
194         }
195
196         if (!tps->valid_gpios) {
197                 ret = regmap_update_bits(tps->regmap,
198                         REG_VSET0 + tps->curr_vset_id, FORCE_PWM_ENABLE, val);
199                 if (ret < 0)
200                         dev_err(tps->dev,
201                                 "%s(): register %d update failed with err %d\n",
202                                 __func__, REG_VSET0 + tps->curr_vset_id, ret);
203                 return ret;
204         }
205
206         /* If gpios are valid then all register set need to be control */
207         for (i = 0; i < 4; ++i) {
208                 ret = regmap_update_bits(tps->regmap,
209                                         REG_VSET0 + i, FORCE_PWM_ENABLE, val);
210                 if (ret < 0) {
211                         dev_err(tps->dev,
212                                 "%s(): register %d update failed with err %d\n",
213                                 __func__, REG_VSET0 + i, ret);
214                         return ret;
215                 }
216         }
217         return ret;
218 }
219
220 static unsigned int tps62360_get_mode(struct regulator_dev *rdev)
221 {
222         struct tps62360_chip *tps = rdev_get_drvdata(rdev);
223         unsigned int data;
224         int ret;
225
226         ret = regmap_read(tps->regmap, REG_VSET0 + tps->curr_vset_id, &data);
227         if (ret < 0) {
228                 dev_err(tps->dev, "%s(): register %d read failed with err %d\n",
229                         __func__, REG_VSET0 + tps->curr_vset_id, ret);
230                 return ret;
231         }
232         return (data & FORCE_PWM_ENABLE) ?
233                                 REGULATOR_MODE_FAST : REGULATOR_MODE_NORMAL;
234 }
235
236 static struct regulator_ops tps62360_dcdc_ops = {
237         .get_voltage_sel        = tps62360_dcdc_get_voltage_sel,
238         .set_voltage_sel        = tps62360_dcdc_set_voltage_sel,
239         .list_voltage           = regulator_list_voltage_linear,
240         .map_voltage            = regulator_map_voltage_linear,
241         .set_voltage_time_sel   = regulator_set_voltage_time_sel,
242         .set_mode               = tps62360_set_mode,
243         .get_mode               = tps62360_get_mode,
244 };
245
246 static int __devinit tps62360_init_dcdc(struct tps62360_chip *tps,
247                 struct tps62360_regulator_platform_data *pdata)
248 {
249         int ret;
250         unsigned int ramp_ctrl;
251
252         /* Initialize internal pull up/down control */
253         if (tps->en_internal_pulldn)
254                 ret = regmap_write(tps->regmap, REG_CONTROL, 0xE0);
255         else
256                 ret = regmap_write(tps->regmap, REG_CONTROL, 0x0);
257         if (ret < 0) {
258                 dev_err(tps->dev,
259                         "%s(): register %d write failed with err %d\n",
260                         __func__, REG_CONTROL, ret);
261                 return ret;
262         }
263
264         /* Reset output discharge path to reduce power consumption */
265         ret = regmap_update_bits(tps->regmap, REG_RAMPCTRL, BIT(2), 0);
266         if (ret < 0) {
267                 dev_err(tps->dev,
268                         "%s(): register %d update failed with err %d\n",
269                         __func__, REG_RAMPCTRL, ret);
270                 return ret;
271         }
272
273         /* Get ramp value from ramp control register */
274         ret = regmap_read(tps->regmap, REG_RAMPCTRL, &ramp_ctrl);
275         if (ret < 0) {
276                 dev_err(tps->dev,
277                         "%s(): register %d read failed with err %d\n",
278                         __func__, REG_RAMPCTRL, ret);
279                 return ret;
280         }
281         ramp_ctrl = (ramp_ctrl >> 4) & 0x7;
282
283         /* ramp mV/us = 32/(2^ramp_ctrl) */
284         tps->desc.ramp_delay = DIV_ROUND_UP(32000, BIT(ramp_ctrl));
285         return ret;
286 }
287
288 static const struct regmap_config tps62360_regmap_config = {
289         .reg_bits               = 8,
290         .val_bits               = 8,
291         .max_register           = REG_CHIPID,
292         .cache_type             = REGCACHE_RBTREE,
293 };
294
295 static struct tps62360_regulator_platform_data *
296         of_get_tps62360_platform_data(struct device *dev)
297 {
298         struct tps62360_regulator_platform_data *pdata;
299         struct device_node *np = dev->of_node;
300
301         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
302         if (!pdata) {
303                 dev_err(dev, "Memory alloc failed for platform data\n");
304                 return NULL;
305         }
306
307         pdata->reg_init_data = of_get_regulator_init_data(dev, dev->of_node);
308         if (!pdata->reg_init_data) {
309                 dev_err(dev, "Not able to get OF regulator init data\n");
310                 return NULL;
311         }
312
313         pdata->vsel0_gpio = of_get_named_gpio(np, "vsel0-gpio", 0);
314         pdata->vsel1_gpio = of_get_named_gpio(np, "vsel1-gpio", 0);
315
316         if (of_find_property(np, "ti,vsel0-state-high", NULL))
317                 pdata->vsel0_def_state = 1;
318
319         if (of_find_property(np, "ti,vsel1-state-high", NULL))
320                 pdata->vsel1_def_state = 1;
321
322         if (of_find_property(np, "ti,enable-pull-down", NULL))
323                 pdata->en_internal_pulldn = true;
324
325         if (of_find_property(np, "ti,enable-vout-discharge", NULL))
326                 pdata->en_discharge = true;
327
328         return pdata;
329 }
330
331 #if defined(CONFIG_OF)
332 static const struct of_device_id tps62360_of_match[] = {
333          { .compatible = "ti,tps62360", .data = (void *)TPS62360},
334          { .compatible = "ti,tps62361", .data = (void *)TPS62361},
335          { .compatible = "ti,tps62362", .data = (void *)TPS62362},
336          { .compatible = "ti,tps62363", .data = (void *)TPS62363},
337         {},
338 };
339 MODULE_DEVICE_TABLE(of, tps62360_of_match);
340 #endif
341
342 static int __devinit tps62360_probe(struct i2c_client *client,
343                                      const struct i2c_device_id *id)
344 {
345         struct regulator_config config = { };
346         struct tps62360_regulator_platform_data *pdata;
347         struct regulator_dev *rdev;
348         struct tps62360_chip *tps;
349         int ret;
350         int i;
351         int chip_id;
352
353         pdata = client->dev.platform_data;
354         chip_id = id->driver_data;
355
356         if (client->dev.of_node) {
357                 const struct of_device_id *match;
358                 match = of_match_device(of_match_ptr(tps62360_of_match),
359                                 &client->dev);
360                 if (!match) {
361                         dev_err(&client->dev, "Error: No device match found\n");
362                         return -ENODEV;
363                 }
364                 chip_id = (int)match->data;
365                 if (!pdata)
366                         pdata = of_get_tps62360_platform_data(&client->dev);
367         }
368
369         if (!pdata) {
370                 dev_err(&client->dev, "%s(): Platform data not found\n",
371                                                 __func__);
372                 return -EIO;
373         }
374
375         tps = devm_kzalloc(&client->dev, sizeof(*tps), GFP_KERNEL);
376         if (!tps) {
377                 dev_err(&client->dev, "%s(): Memory allocation failed\n",
378                                                 __func__);
379                 return -ENOMEM;
380         }
381
382         tps->en_discharge = pdata->en_discharge;
383         tps->en_internal_pulldn = pdata->en_internal_pulldn;
384         tps->vsel0_gpio = pdata->vsel0_gpio;
385         tps->vsel1_gpio = pdata->vsel1_gpio;
386         tps->dev = &client->dev;
387
388         switch (chip_id) {
389         case TPS62360:
390         case TPS62362:
391                 tps->desc.min_uV = TPS62360_BASE_VOLTAGE;
392                 tps->voltage_reg_mask = 0x3F;
393                 tps->desc.n_voltages = TPS62360_N_VOLTAGES;
394                 break;
395         case TPS62361:
396         case TPS62363:
397                 tps->desc.min_uV = TPS62361_BASE_VOLTAGE;
398                 tps->voltage_reg_mask = 0x7F;
399                 tps->desc.n_voltages = TPS62361_N_VOLTAGES;
400                 break;
401         default:
402                 return -ENODEV;
403         }
404
405         tps->desc.name = id->name;
406         tps->desc.id = 0;
407         tps->desc.ops = &tps62360_dcdc_ops;
408         tps->desc.type = REGULATOR_VOLTAGE;
409         tps->desc.owner = THIS_MODULE;
410         tps->desc.uV_step = 10000;
411
412         tps->regmap = devm_regmap_init_i2c(client, &tps62360_regmap_config);
413         if (IS_ERR(tps->regmap)) {
414                 ret = PTR_ERR(tps->regmap);
415                 dev_err(&client->dev,
416                         "%s(): regmap allocation failed with err %d\n",
417                         __func__, ret);
418                 return ret;
419         }
420         i2c_set_clientdata(client, tps);
421
422         tps->curr_vset_id = (pdata->vsel1_def_state & 1) * 2 +
423                                 (pdata->vsel0_def_state & 1);
424         tps->lru_index[0] = tps->curr_vset_id;
425         tps->valid_gpios = false;
426
427         if (gpio_is_valid(tps->vsel0_gpio) && gpio_is_valid(tps->vsel1_gpio)) {
428                 int gpio_flags;
429                 gpio_flags = (pdata->vsel0_def_state) ?
430                                 GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW;
431                 ret = devm_gpio_request_one(&client->dev, tps->vsel0_gpio,
432                                 gpio_flags, "tps62360-vsel0");
433                 if (ret) {
434                         dev_err(&client->dev,
435                                 "%s(): Could not obtain vsel0 GPIO %d: %d\n",
436                                 __func__, tps->vsel0_gpio, ret);
437                         return ret;
438                 }
439
440                 gpio_flags = (pdata->vsel1_def_state) ?
441                                 GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW;
442                 ret = devm_gpio_request_one(&client->dev, tps->vsel1_gpio,
443                                 gpio_flags, "tps62360-vsel1");
444                 if (ret) {
445                         dev_err(&client->dev,
446                                 "%s(): Could not obtain vsel1 GPIO %d: %d\n",
447                                 __func__, tps->vsel1_gpio, ret);
448                         return ret;
449                 }
450                 tps->valid_gpios = true;
451
452                 /*
453                  * Initialize the lru index with vset_reg id
454                  * The index 0 will be most recently used and
455                  * set with the tps->curr_vset_id */
456                 for (i = 0; i < 4; ++i)
457                         tps->lru_index[i] = i;
458                 tps->lru_index[0] = tps->curr_vset_id;
459                 tps->lru_index[tps->curr_vset_id] = 0;
460         }
461
462         ret = tps62360_init_dcdc(tps, pdata);
463         if (ret < 0) {
464                 dev_err(tps->dev, "%s(): Init failed with err = %d\n",
465                                 __func__, ret);
466                 return ret;
467         }
468
469         config.dev = &client->dev;
470         config.init_data = pdata->reg_init_data;
471         config.driver_data = tps;
472         config.of_node = client->dev.of_node;
473
474         /* Register the regulators */
475         rdev = regulator_register(&tps->desc, &config);
476         if (IS_ERR(rdev)) {
477                 dev_err(tps->dev,
478                         "%s(): regulator register failed with err %s\n",
479                         __func__, id->name);
480                 return PTR_ERR(rdev);
481         }
482
483         tps->rdev = rdev;
484         return 0;
485 }
486
487 /**
488  * tps62360_remove - tps62360 driver i2c remove handler
489  * @client: i2c driver client device structure
490  *
491  * Unregister TPS driver as an i2c client device driver
492  */
493 static int __devexit tps62360_remove(struct i2c_client *client)
494 {
495         struct tps62360_chip *tps = i2c_get_clientdata(client);
496
497         regulator_unregister(tps->rdev);
498         return 0;
499 }
500
501 static void tps62360_shutdown(struct i2c_client *client)
502 {
503         struct tps62360_chip *tps = i2c_get_clientdata(client);
504         int st;
505
506         if (!tps->en_discharge)
507                 return;
508
509         /* Configure the output discharge path */
510         st = regmap_update_bits(tps->regmap, REG_RAMPCTRL, BIT(2), BIT(2));
511         if (st < 0)
512                 dev_err(tps->dev,
513                         "%s(): register %d update failed with err %d\n",
514                         __func__, REG_RAMPCTRL, st);
515 }
516
517 static const struct i2c_device_id tps62360_id[] = {
518         {.name = "tps62360", .driver_data = TPS62360},
519         {.name = "tps62361", .driver_data = TPS62361},
520         {.name = "tps62362", .driver_data = TPS62362},
521         {.name = "tps62363", .driver_data = TPS62363},
522         {},
523 };
524
525 MODULE_DEVICE_TABLE(i2c, tps62360_id);
526
527 static struct i2c_driver tps62360_i2c_driver = {
528         .driver = {
529                 .name = "tps62360",
530                 .owner = THIS_MODULE,
531                 .of_match_table = of_match_ptr(tps62360_of_match),
532         },
533         .probe = tps62360_probe,
534         .remove = __devexit_p(tps62360_remove),
535         .shutdown = tps62360_shutdown,
536         .id_table = tps62360_id,
537 };
538
539 static int __init tps62360_init(void)
540 {
541         return i2c_add_driver(&tps62360_i2c_driver);
542 }
543 subsys_initcall(tps62360_init);
544
545 static void __exit tps62360_cleanup(void)
546 {
547         i2c_del_driver(&tps62360_i2c_driver);
548 }
549 module_exit(tps62360_cleanup);
550
551 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
552 MODULE_DESCRIPTION("TPS6236x voltage regulator driver");
553 MODULE_LICENSE("GPL v2");