cifs: fix oops while traversing open file list (try #4)
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / regulator / lp3971.c
blob0f22ef12601c2204170edb3d00eb38c0319e0976
1 /*
2 * Regulator driver for National Semiconductors LP3971 PMIC chip
4 * Copyright (C) 2009 Samsung Electronics
5 * Author: Marek Szyprowski <m.szyprowski@samsung.com>
7 * Based on wm8350.c
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
15 #include <linux/bug.h>
16 #include <linux/err.h>
17 #include <linux/i2c.h>
18 #include <linux/kernel.h>
19 #include <linux/regulator/driver.h>
20 #include <linux/regulator/lp3971.h>
21 #include <linux/slab.h>
23 struct lp3971 {
24 struct device *dev;
25 struct mutex io_lock;
26 struct i2c_client *i2c;
27 int num_regulators;
28 struct regulator_dev **rdev;
31 static u8 lp3971_reg_read(struct lp3971 *lp3971, u8 reg);
32 static int lp3971_set_bits(struct lp3971 *lp3971, u8 reg, u16 mask, u16 val);
34 #define LP3971_SYS_CONTROL1_REG 0x07
36 /* System control register 1 initial value,
37 bits 4 and 5 are EPROM programmable */
38 #define SYS_CONTROL1_INIT_VAL 0x40
39 #define SYS_CONTROL1_INIT_MASK 0xCF
41 #define LP3971_BUCK_VOL_ENABLE_REG 0x10
42 #define LP3971_BUCK_VOL_CHANGE_REG 0x20
44 /* Voltage control registers shift:
45 LP3971_BUCK1 -> 0
46 LP3971_BUCK2 -> 4
47 LP3971_BUCK3 -> 6
49 #define BUCK_VOL_CHANGE_SHIFT(x) (((!!x) << 2) | (x & ~0x01))
50 #define BUCK_VOL_CHANGE_FLAG_GO 0x01
51 #define BUCK_VOL_CHANGE_FLAG_TARGET 0x02
52 #define BUCK_VOL_CHANGE_FLAG_MASK 0x03
54 #define LP3971_BUCK1_BASE 0x23
55 #define LP3971_BUCK2_BASE 0x29
56 #define LP3971_BUCK3_BASE 0x32
58 static const int buck_base_addr[] = {
59 LP3971_BUCK1_BASE,
60 LP3971_BUCK2_BASE,
61 LP3971_BUCK3_BASE,
64 #define LP3971_BUCK_TARGET_VOL1_REG(x) (buck_base_addr[x])
65 #define LP3971_BUCK_TARGET_VOL2_REG(x) (buck_base_addr[x]+1)
67 static const int buck_voltage_map[] = {
68 0, 800, 850, 900, 950, 1000, 1050, 1100,
69 1150, 1200, 1250, 1300, 1350, 1400, 1450, 1500,
70 1550, 1600, 1650, 1700, 1800, 1900, 2500, 2800,
71 3000, 3300,
74 #define BUCK_TARGET_VOL_MASK 0x3f
75 #define BUCK_TARGET_VOL_MIN_IDX 0x01
76 #define BUCK_TARGET_VOL_MAX_IDX 0x19
78 #define LP3971_BUCK_RAMP_REG(x) (buck_base_addr[x]+2)
80 #define LP3971_LDO_ENABLE_REG 0x12
81 #define LP3971_LDO_VOL_CONTR_BASE 0x39
83 /* Voltage control registers:
84 LP3971_LDO1 -> LP3971_LDO_VOL_CONTR_BASE + 0
85 LP3971_LDO2 -> LP3971_LDO_VOL_CONTR_BASE + 0
86 LP3971_LDO3 -> LP3971_LDO_VOL_CONTR_BASE + 1
87 LP3971_LDO4 -> LP3971_LDO_VOL_CONTR_BASE + 1
88 LP3971_LDO5 -> LP3971_LDO_VOL_CONTR_BASE + 2
90 #define LP3971_LDO_VOL_CONTR_REG(x) (LP3971_LDO_VOL_CONTR_BASE + (x >> 1))
92 /* Voltage control registers shift:
93 LP3971_LDO1 -> 0, LP3971_LDO2 -> 4
94 LP3971_LDO3 -> 0, LP3971_LDO4 -> 4
95 LP3971_LDO5 -> 0
97 #define LDO_VOL_CONTR_SHIFT(x) ((x & 1) << 2)
98 #define LDO_VOL_CONTR_MASK 0x0f
100 static const int ldo45_voltage_map[] = {
101 1000, 1050, 1100, 1150, 1200, 1250, 1300, 1350,
102 1400, 1500, 1800, 1900, 2500, 2800, 3000, 3300,
105 static const int ldo123_voltage_map[] = {
106 1800, 1900, 2000, 2100, 2200, 2300, 2400, 2500,
107 2600, 2700, 2800, 2900, 3000, 3100, 3200, 3300,
110 static const int *ldo_voltage_map[] = {
111 ldo123_voltage_map, /* LDO1 */
112 ldo123_voltage_map, /* LDO2 */
113 ldo123_voltage_map, /* LDO3 */
114 ldo45_voltage_map, /* LDO4 */
115 ldo45_voltage_map, /* LDO5 */
118 #define LDO_VOL_VALUE_MAP(x) (ldo_voltage_map[(x - LP3971_LDO1)])
120 #define LDO_VOL_MIN_IDX 0x00
121 #define LDO_VOL_MAX_IDX 0x0f
123 static int lp3971_ldo_list_voltage(struct regulator_dev *dev, unsigned index)
125 int ldo = rdev_get_id(dev) - LP3971_LDO1;
126 return 1000 * LDO_VOL_VALUE_MAP(ldo)[index];
129 static int lp3971_ldo_is_enabled(struct regulator_dev *dev)
131 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
132 int ldo = rdev_get_id(dev) - LP3971_LDO1;
133 u16 mask = 1 << (1 + ldo);
134 u16 val;
136 val = lp3971_reg_read(lp3971, LP3971_LDO_ENABLE_REG);
137 return (val & mask) != 0;
140 static int lp3971_ldo_enable(struct regulator_dev *dev)
142 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
143 int ldo = rdev_get_id(dev) - LP3971_LDO1;
144 u16 mask = 1 << (1 + ldo);
146 return lp3971_set_bits(lp3971, LP3971_LDO_ENABLE_REG, mask, mask);
149 static int lp3971_ldo_disable(struct regulator_dev *dev)
151 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
152 int ldo = rdev_get_id(dev) - LP3971_LDO1;
153 u16 mask = 1 << (1 + ldo);
155 return lp3971_set_bits(lp3971, LP3971_LDO_ENABLE_REG, mask, 0);
158 static int lp3971_ldo_get_voltage(struct regulator_dev *dev)
160 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
161 int ldo = rdev_get_id(dev) - LP3971_LDO1;
162 u16 val, reg;
164 reg = lp3971_reg_read(lp3971, LP3971_LDO_VOL_CONTR_REG(ldo));
165 val = (reg >> LDO_VOL_CONTR_SHIFT(ldo)) & LDO_VOL_CONTR_MASK;
167 return 1000 * LDO_VOL_VALUE_MAP(ldo)[val];
170 static int lp3971_ldo_set_voltage(struct regulator_dev *dev,
171 int min_uV, int max_uV,
172 unsigned int *selector)
174 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
175 int ldo = rdev_get_id(dev) - LP3971_LDO1;
176 int min_vol = min_uV / 1000, max_vol = max_uV / 1000;
177 const int *vol_map = LDO_VOL_VALUE_MAP(ldo);
178 u16 val;
180 if (min_vol < vol_map[LDO_VOL_MIN_IDX] ||
181 min_vol > vol_map[LDO_VOL_MAX_IDX])
182 return -EINVAL;
184 for (val = LDO_VOL_MIN_IDX; val <= LDO_VOL_MAX_IDX; val++)
185 if (vol_map[val] >= min_vol)
186 break;
188 if (val > LDO_VOL_MAX_IDX || vol_map[val] > max_vol)
189 return -EINVAL;
191 *selector = val;
193 return lp3971_set_bits(lp3971, LP3971_LDO_VOL_CONTR_REG(ldo),
194 LDO_VOL_CONTR_MASK << LDO_VOL_CONTR_SHIFT(ldo),
195 val << LDO_VOL_CONTR_SHIFT(ldo));
198 static struct regulator_ops lp3971_ldo_ops = {
199 .list_voltage = lp3971_ldo_list_voltage,
200 .is_enabled = lp3971_ldo_is_enabled,
201 .enable = lp3971_ldo_enable,
202 .disable = lp3971_ldo_disable,
203 .get_voltage = lp3971_ldo_get_voltage,
204 .set_voltage = lp3971_ldo_set_voltage,
207 static int lp3971_dcdc_list_voltage(struct regulator_dev *dev, unsigned index)
209 return 1000 * buck_voltage_map[index];
212 static int lp3971_dcdc_is_enabled(struct regulator_dev *dev)
214 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
215 int buck = rdev_get_id(dev) - LP3971_DCDC1;
216 u16 mask = 1 << (buck * 2);
217 u16 val;
219 val = lp3971_reg_read(lp3971, LP3971_BUCK_VOL_ENABLE_REG);
220 return (val & mask) != 0;
223 static int lp3971_dcdc_enable(struct regulator_dev *dev)
225 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
226 int buck = rdev_get_id(dev) - LP3971_DCDC1;
227 u16 mask = 1 << (buck * 2);
229 return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_ENABLE_REG, mask, mask);
232 static int lp3971_dcdc_disable(struct regulator_dev *dev)
234 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
235 int buck = rdev_get_id(dev) - LP3971_DCDC1;
236 u16 mask = 1 << (buck * 2);
238 return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_ENABLE_REG, mask, 0);
241 static int lp3971_dcdc_get_voltage(struct regulator_dev *dev)
243 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
244 int buck = rdev_get_id(dev) - LP3971_DCDC1;
245 u16 reg;
246 int val;
248 reg = lp3971_reg_read(lp3971, LP3971_BUCK_TARGET_VOL1_REG(buck));
249 reg &= BUCK_TARGET_VOL_MASK;
251 if (reg <= BUCK_TARGET_VOL_MAX_IDX)
252 val = 1000 * buck_voltage_map[reg];
253 else {
254 val = 0;
255 dev_warn(&dev->dev, "chip reported incorrect voltage value.\n");
258 return val;
261 static int lp3971_dcdc_set_voltage(struct regulator_dev *dev,
262 int min_uV, int max_uV,
263 unsigned int *selector)
265 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
266 int buck = rdev_get_id(dev) - LP3971_DCDC1;
267 int min_vol = min_uV / 1000, max_vol = max_uV / 1000;
268 const int *vol_map = buck_voltage_map;
269 u16 val;
270 int ret;
272 if (min_vol < vol_map[BUCK_TARGET_VOL_MIN_IDX] ||
273 min_vol > vol_map[BUCK_TARGET_VOL_MAX_IDX])
274 return -EINVAL;
276 for (val = BUCK_TARGET_VOL_MIN_IDX; val <= BUCK_TARGET_VOL_MAX_IDX;
277 val++)
278 if (vol_map[val] >= min_vol)
279 break;
281 if (val > BUCK_TARGET_VOL_MAX_IDX || vol_map[val] > max_vol)
282 return -EINVAL;
284 *selector = val;
286 ret = lp3971_set_bits(lp3971, LP3971_BUCK_TARGET_VOL1_REG(buck),
287 BUCK_TARGET_VOL_MASK, val);
288 if (ret)
289 return ret;
291 ret = lp3971_set_bits(lp3971, LP3971_BUCK_VOL_CHANGE_REG,
292 BUCK_VOL_CHANGE_FLAG_MASK << BUCK_VOL_CHANGE_SHIFT(buck),
293 BUCK_VOL_CHANGE_FLAG_GO << BUCK_VOL_CHANGE_SHIFT(buck));
294 if (ret)
295 return ret;
297 return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_CHANGE_REG,
298 BUCK_VOL_CHANGE_FLAG_MASK << BUCK_VOL_CHANGE_SHIFT(buck),
299 0 << BUCK_VOL_CHANGE_SHIFT(buck));
302 static struct regulator_ops lp3971_dcdc_ops = {
303 .list_voltage = lp3971_dcdc_list_voltage,
304 .is_enabled = lp3971_dcdc_is_enabled,
305 .enable = lp3971_dcdc_enable,
306 .disable = lp3971_dcdc_disable,
307 .get_voltage = lp3971_dcdc_get_voltage,
308 .set_voltage = lp3971_dcdc_set_voltage,
311 static struct regulator_desc regulators[] = {
313 .name = "LDO1",
314 .id = LP3971_LDO1,
315 .ops = &lp3971_ldo_ops,
316 .n_voltages = ARRAY_SIZE(ldo123_voltage_map),
317 .type = REGULATOR_VOLTAGE,
318 .owner = THIS_MODULE,
321 .name = "LDO2",
322 .id = LP3971_LDO2,
323 .ops = &lp3971_ldo_ops,
324 .n_voltages = ARRAY_SIZE(ldo123_voltage_map),
325 .type = REGULATOR_VOLTAGE,
326 .owner = THIS_MODULE,
329 .name = "LDO3",
330 .id = LP3971_LDO3,
331 .ops = &lp3971_ldo_ops,
332 .n_voltages = ARRAY_SIZE(ldo123_voltage_map),
333 .type = REGULATOR_VOLTAGE,
334 .owner = THIS_MODULE,
337 .name = "LDO4",
338 .id = LP3971_LDO4,
339 .ops = &lp3971_ldo_ops,
340 .n_voltages = ARRAY_SIZE(ldo45_voltage_map),
341 .type = REGULATOR_VOLTAGE,
342 .owner = THIS_MODULE,
345 .name = "LDO5",
346 .id = LP3971_LDO5,
347 .ops = &lp3971_ldo_ops,
348 .n_voltages = ARRAY_SIZE(ldo45_voltage_map),
349 .type = REGULATOR_VOLTAGE,
350 .owner = THIS_MODULE,
353 .name = "DCDC1",
354 .id = LP3971_DCDC1,
355 .ops = &lp3971_dcdc_ops,
356 .n_voltages = ARRAY_SIZE(buck_voltage_map),
357 .type = REGULATOR_VOLTAGE,
358 .owner = THIS_MODULE,
361 .name = "DCDC2",
362 .id = LP3971_DCDC2,
363 .ops = &lp3971_dcdc_ops,
364 .n_voltages = ARRAY_SIZE(buck_voltage_map),
365 .type = REGULATOR_VOLTAGE,
366 .owner = THIS_MODULE,
369 .name = "DCDC3",
370 .id = LP3971_DCDC3,
371 .ops = &lp3971_dcdc_ops,
372 .n_voltages = ARRAY_SIZE(buck_voltage_map),
373 .type = REGULATOR_VOLTAGE,
374 .owner = THIS_MODULE,
378 static int lp3971_i2c_read(struct i2c_client *i2c, char reg, int count,
379 u16 *dest)
381 int ret;
383 if (count != 1)
384 return -EIO;
385 ret = i2c_smbus_read_byte_data(i2c, reg);
386 if (ret < 0)
387 return -EIO;
389 *dest = ret;
390 return 0;
393 static int lp3971_i2c_write(struct i2c_client *i2c, char reg, int count,
394 const u16 *src)
396 if (count != 1)
397 return -EIO;
398 return i2c_smbus_write_byte_data(i2c, reg, *src);
401 static u8 lp3971_reg_read(struct lp3971 *lp3971, u8 reg)
403 u16 val = 0;
405 mutex_lock(&lp3971->io_lock);
407 lp3971_i2c_read(lp3971->i2c, reg, 1, &val);
409 dev_dbg(lp3971->dev, "reg read 0x%02x -> 0x%02x\n", (int)reg,
410 (unsigned)val&0xff);
412 mutex_unlock(&lp3971->io_lock);
414 return val & 0xff;
417 static int lp3971_set_bits(struct lp3971 *lp3971, u8 reg, u16 mask, u16 val)
419 u16 tmp;
420 int ret;
422 mutex_lock(&lp3971->io_lock);
424 ret = lp3971_i2c_read(lp3971->i2c, reg, 1, &tmp);
425 tmp = (tmp & ~mask) | val;
426 if (ret == 0) {
427 ret = lp3971_i2c_write(lp3971->i2c, reg, 1, &tmp);
428 dev_dbg(lp3971->dev, "reg write 0x%02x -> 0x%02x\n", (int)reg,
429 (unsigned)val&0xff);
431 mutex_unlock(&lp3971->io_lock);
433 return ret;
436 static int __devinit setup_regulators(struct lp3971 *lp3971,
437 struct lp3971_platform_data *pdata)
439 int i, err;
441 lp3971->num_regulators = pdata->num_regulators;
442 lp3971->rdev = kcalloc(pdata->num_regulators,
443 sizeof(struct regulator_dev *), GFP_KERNEL);
444 if (!lp3971->rdev) {
445 err = -ENOMEM;
446 goto err_nomem;
449 /* Instantiate the regulators */
450 for (i = 0; i < pdata->num_regulators; i++) {
451 struct lp3971_regulator_subdev *reg = &pdata->regulators[i];
452 lp3971->rdev[i] = regulator_register(&regulators[reg->id],
453 lp3971->dev, reg->initdata, lp3971);
455 if (IS_ERR(lp3971->rdev[i])) {
456 err = PTR_ERR(lp3971->rdev[i]);
457 dev_err(lp3971->dev, "regulator init failed: %d\n",
458 err);
459 goto error;
463 return 0;
465 error:
466 while (--i >= 0)
467 regulator_unregister(lp3971->rdev[i]);
468 kfree(lp3971->rdev);
469 lp3971->rdev = NULL;
470 err_nomem:
471 return err;
474 static int __devinit lp3971_i2c_probe(struct i2c_client *i2c,
475 const struct i2c_device_id *id)
477 struct lp3971 *lp3971;
478 struct lp3971_platform_data *pdata = i2c->dev.platform_data;
479 int ret;
480 u16 val;
482 if (!pdata) {
483 dev_dbg(&i2c->dev, "No platform init data supplied\n");
484 return -ENODEV;
487 lp3971 = kzalloc(sizeof(struct lp3971), GFP_KERNEL);
488 if (lp3971 == NULL)
489 return -ENOMEM;
491 lp3971->i2c = i2c;
492 lp3971->dev = &i2c->dev;
494 mutex_init(&lp3971->io_lock);
496 /* Detect LP3971 */
497 ret = lp3971_i2c_read(i2c, LP3971_SYS_CONTROL1_REG, 1, &val);
498 if (ret == 0 && (val & SYS_CONTROL1_INIT_MASK) != SYS_CONTROL1_INIT_VAL)
499 ret = -ENODEV;
500 if (ret < 0) {
501 dev_err(&i2c->dev, "failed to detect device\n");
502 goto err_detect;
505 ret = setup_regulators(lp3971, pdata);
506 if (ret < 0)
507 goto err_detect;
509 i2c_set_clientdata(i2c, lp3971);
510 return 0;
512 err_detect:
513 kfree(lp3971);
514 return ret;
517 static int __devexit lp3971_i2c_remove(struct i2c_client *i2c)
519 struct lp3971 *lp3971 = i2c_get_clientdata(i2c);
520 int i;
522 for (i = 0; i < lp3971->num_regulators; i++)
523 regulator_unregister(lp3971->rdev[i]);
525 kfree(lp3971->rdev);
526 kfree(lp3971);
528 return 0;
531 static const struct i2c_device_id lp3971_i2c_id[] = {
532 { "lp3971", 0 },
535 MODULE_DEVICE_TABLE(i2c, lp3971_i2c_id);
537 static struct i2c_driver lp3971_i2c_driver = {
538 .driver = {
539 .name = "LP3971",
540 .owner = THIS_MODULE,
542 .probe = lp3971_i2c_probe,
543 .remove = __devexit_p(lp3971_i2c_remove),
544 .id_table = lp3971_i2c_id,
547 static int __init lp3971_module_init(void)
549 int ret;
551 ret = i2c_add_driver(&lp3971_i2c_driver);
552 if (ret != 0)
553 pr_err("Failed to register I2C driver: %d\n", ret);
555 return ret;
557 module_init(lp3971_module_init);
559 static void __exit lp3971_module_exit(void)
561 i2c_del_driver(&lp3971_i2c_driver);
563 module_exit(lp3971_module_exit);
565 MODULE_LICENSE("GPL");
566 MODULE_AUTHOR("Marek Szyprowski <m.szyprowski@samsung.com>");
567 MODULE_DESCRIPTION("LP3971 PMIC driver");