serial: fix race between flush_to_ldisc and tty_open
[linux-stable.git] / drivers / regulator / lp3971.c
blob204b5c5270e05708ddbd83937cbc69fc8c5fe655
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/module.h>
20 #include <linux/regulator/driver.h>
21 #include <linux/regulator/lp3971.h>
22 #include <linux/slab.h>
24 struct lp3971 {
25 struct device *dev;
26 struct mutex io_lock;
27 struct i2c_client *i2c;
30 static u8 lp3971_reg_read(struct lp3971 *lp3971, u8 reg);
31 static int lp3971_set_bits(struct lp3971 *lp3971, u8 reg, u16 mask, u16 val);
33 #define LP3971_SYS_CONTROL1_REG 0x07
35 /* System control register 1 initial value,
36 bits 4 and 5 are EPROM programmable */
37 #define SYS_CONTROL1_INIT_VAL 0x40
38 #define SYS_CONTROL1_INIT_MASK 0xCF
40 #define LP3971_BUCK_VOL_ENABLE_REG 0x10
41 #define LP3971_BUCK_VOL_CHANGE_REG 0x20
43 /* Voltage control registers shift:
44 LP3971_BUCK1 -> 0
45 LP3971_BUCK2 -> 4
46 LP3971_BUCK3 -> 6
48 #define BUCK_VOL_CHANGE_SHIFT(x) (((!!x) << 2) | (x & ~0x01))
49 #define BUCK_VOL_CHANGE_FLAG_GO 0x01
50 #define BUCK_VOL_CHANGE_FLAG_TARGET 0x02
51 #define BUCK_VOL_CHANGE_FLAG_MASK 0x03
53 #define LP3971_BUCK1_BASE 0x23
54 #define LP3971_BUCK2_BASE 0x29
55 #define LP3971_BUCK3_BASE 0x32
57 static const int buck_base_addr[] = {
58 LP3971_BUCK1_BASE,
59 LP3971_BUCK2_BASE,
60 LP3971_BUCK3_BASE,
63 #define LP3971_BUCK_TARGET_VOL1_REG(x) (buck_base_addr[x])
64 #define LP3971_BUCK_TARGET_VOL2_REG(x) (buck_base_addr[x]+1)
66 static const unsigned int buck_voltage_map[] = {
67 0, 800000, 850000, 900000, 950000, 1000000, 1050000, 1100000,
68 1150000, 1200000, 1250000, 1300000, 1350000, 1400000, 1450000, 1500000,
69 1550000, 1600000, 1650000, 1700000, 1800000, 1900000, 2500000, 2800000,
70 3000000, 3300000,
73 #define BUCK_TARGET_VOL_MASK 0x3f
75 #define LP3971_BUCK_RAMP_REG(x) (buck_base_addr[x]+2)
77 #define LP3971_LDO_ENABLE_REG 0x12
78 #define LP3971_LDO_VOL_CONTR_BASE 0x39
80 /* Voltage control registers:
81 LP3971_LDO1 -> LP3971_LDO_VOL_CONTR_BASE + 0
82 LP3971_LDO2 -> LP3971_LDO_VOL_CONTR_BASE + 0
83 LP3971_LDO3 -> LP3971_LDO_VOL_CONTR_BASE + 1
84 LP3971_LDO4 -> LP3971_LDO_VOL_CONTR_BASE + 1
85 LP3971_LDO5 -> LP3971_LDO_VOL_CONTR_BASE + 2
87 #define LP3971_LDO_VOL_CONTR_REG(x) (LP3971_LDO_VOL_CONTR_BASE + (x >> 1))
89 /* Voltage control registers shift:
90 LP3971_LDO1 -> 0, LP3971_LDO2 -> 4
91 LP3971_LDO3 -> 0, LP3971_LDO4 -> 4
92 LP3971_LDO5 -> 0
94 #define LDO_VOL_CONTR_SHIFT(x) ((x & 1) << 2)
95 #define LDO_VOL_CONTR_MASK 0x0f
97 static const unsigned int ldo45_voltage_map[] = {
98 1000000, 1050000, 1100000, 1150000, 1200000, 1250000, 1300000, 1350000,
99 1400000, 1500000, 1800000, 1900000, 2500000, 2800000, 3000000, 3300000,
102 static const unsigned int ldo123_voltage_map[] = {
103 1800000, 1900000, 2000000, 2100000, 2200000, 2300000, 2400000, 2500000,
104 2600000, 2700000, 2800000, 2900000, 3000000, 3100000, 3200000, 3300000,
107 #define LDO_VOL_MIN_IDX 0x00
108 #define LDO_VOL_MAX_IDX 0x0f
110 static int lp3971_ldo_is_enabled(struct regulator_dev *dev)
112 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
113 int ldo = rdev_get_id(dev) - LP3971_LDO1;
114 u16 mask = 1 << (1 + ldo);
115 u16 val;
117 val = lp3971_reg_read(lp3971, LP3971_LDO_ENABLE_REG);
118 return (val & mask) != 0;
121 static int lp3971_ldo_enable(struct regulator_dev *dev)
123 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
124 int ldo = rdev_get_id(dev) - LP3971_LDO1;
125 u16 mask = 1 << (1 + ldo);
127 return lp3971_set_bits(lp3971, LP3971_LDO_ENABLE_REG, mask, mask);
130 static int lp3971_ldo_disable(struct regulator_dev *dev)
132 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
133 int ldo = rdev_get_id(dev) - LP3971_LDO1;
134 u16 mask = 1 << (1 + ldo);
136 return lp3971_set_bits(lp3971, LP3971_LDO_ENABLE_REG, mask, 0);
139 static int lp3971_ldo_get_voltage_sel(struct regulator_dev *dev)
141 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
142 int ldo = rdev_get_id(dev) - LP3971_LDO1;
143 u16 val, reg;
145 reg = lp3971_reg_read(lp3971, LP3971_LDO_VOL_CONTR_REG(ldo));
146 val = (reg >> LDO_VOL_CONTR_SHIFT(ldo)) & LDO_VOL_CONTR_MASK;
148 return val;
151 static int lp3971_ldo_set_voltage_sel(struct regulator_dev *dev,
152 unsigned int selector)
154 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
155 int ldo = rdev_get_id(dev) - LP3971_LDO1;
157 return lp3971_set_bits(lp3971, LP3971_LDO_VOL_CONTR_REG(ldo),
158 LDO_VOL_CONTR_MASK << LDO_VOL_CONTR_SHIFT(ldo),
159 selector << LDO_VOL_CONTR_SHIFT(ldo));
162 static struct regulator_ops lp3971_ldo_ops = {
163 .list_voltage = regulator_list_voltage_table,
164 .map_voltage = regulator_map_voltage_ascend,
165 .is_enabled = lp3971_ldo_is_enabled,
166 .enable = lp3971_ldo_enable,
167 .disable = lp3971_ldo_disable,
168 .get_voltage_sel = lp3971_ldo_get_voltage_sel,
169 .set_voltage_sel = lp3971_ldo_set_voltage_sel,
172 static int lp3971_dcdc_is_enabled(struct regulator_dev *dev)
174 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
175 int buck = rdev_get_id(dev) - LP3971_DCDC1;
176 u16 mask = 1 << (buck * 2);
177 u16 val;
179 val = lp3971_reg_read(lp3971, LP3971_BUCK_VOL_ENABLE_REG);
180 return (val & mask) != 0;
183 static int lp3971_dcdc_enable(struct regulator_dev *dev)
185 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
186 int buck = rdev_get_id(dev) - LP3971_DCDC1;
187 u16 mask = 1 << (buck * 2);
189 return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_ENABLE_REG, mask, mask);
192 static int lp3971_dcdc_disable(struct regulator_dev *dev)
194 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
195 int buck = rdev_get_id(dev) - LP3971_DCDC1;
196 u16 mask = 1 << (buck * 2);
198 return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_ENABLE_REG, mask, 0);
201 static int lp3971_dcdc_get_voltage_sel(struct regulator_dev *dev)
203 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
204 int buck = rdev_get_id(dev) - LP3971_DCDC1;
205 u16 reg;
207 reg = lp3971_reg_read(lp3971, LP3971_BUCK_TARGET_VOL1_REG(buck));
208 reg &= BUCK_TARGET_VOL_MASK;
210 return reg;
213 static int lp3971_dcdc_set_voltage_sel(struct regulator_dev *dev,
214 unsigned int selector)
216 struct lp3971 *lp3971 = rdev_get_drvdata(dev);
217 int buck = rdev_get_id(dev) - LP3971_DCDC1;
218 int ret;
220 ret = lp3971_set_bits(lp3971, LP3971_BUCK_TARGET_VOL1_REG(buck),
221 BUCK_TARGET_VOL_MASK, selector);
222 if (ret)
223 return ret;
225 ret = lp3971_set_bits(lp3971, LP3971_BUCK_VOL_CHANGE_REG,
226 BUCK_VOL_CHANGE_FLAG_MASK << BUCK_VOL_CHANGE_SHIFT(buck),
227 BUCK_VOL_CHANGE_FLAG_GO << BUCK_VOL_CHANGE_SHIFT(buck));
228 if (ret)
229 return ret;
231 return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_CHANGE_REG,
232 BUCK_VOL_CHANGE_FLAG_MASK << BUCK_VOL_CHANGE_SHIFT(buck),
233 0 << BUCK_VOL_CHANGE_SHIFT(buck));
236 static struct regulator_ops lp3971_dcdc_ops = {
237 .list_voltage = regulator_list_voltage_table,
238 .map_voltage = regulator_map_voltage_ascend,
239 .is_enabled = lp3971_dcdc_is_enabled,
240 .enable = lp3971_dcdc_enable,
241 .disable = lp3971_dcdc_disable,
242 .get_voltage_sel = lp3971_dcdc_get_voltage_sel,
243 .set_voltage_sel = lp3971_dcdc_set_voltage_sel,
246 static const struct regulator_desc regulators[] = {
248 .name = "LDO1",
249 .id = LP3971_LDO1,
250 .ops = &lp3971_ldo_ops,
251 .n_voltages = ARRAY_SIZE(ldo123_voltage_map),
252 .volt_table = ldo123_voltage_map,
253 .type = REGULATOR_VOLTAGE,
254 .owner = THIS_MODULE,
257 .name = "LDO2",
258 .id = LP3971_LDO2,
259 .ops = &lp3971_ldo_ops,
260 .n_voltages = ARRAY_SIZE(ldo123_voltage_map),
261 .volt_table = ldo123_voltage_map,
262 .type = REGULATOR_VOLTAGE,
263 .owner = THIS_MODULE,
266 .name = "LDO3",
267 .id = LP3971_LDO3,
268 .ops = &lp3971_ldo_ops,
269 .n_voltages = ARRAY_SIZE(ldo123_voltage_map),
270 .volt_table = ldo123_voltage_map,
271 .type = REGULATOR_VOLTAGE,
272 .owner = THIS_MODULE,
275 .name = "LDO4",
276 .id = LP3971_LDO4,
277 .ops = &lp3971_ldo_ops,
278 .n_voltages = ARRAY_SIZE(ldo45_voltage_map),
279 .volt_table = ldo45_voltage_map,
280 .type = REGULATOR_VOLTAGE,
281 .owner = THIS_MODULE,
284 .name = "LDO5",
285 .id = LP3971_LDO5,
286 .ops = &lp3971_ldo_ops,
287 .n_voltages = ARRAY_SIZE(ldo45_voltage_map),
288 .volt_table = ldo45_voltage_map,
289 .type = REGULATOR_VOLTAGE,
290 .owner = THIS_MODULE,
293 .name = "DCDC1",
294 .id = LP3971_DCDC1,
295 .ops = &lp3971_dcdc_ops,
296 .n_voltages = ARRAY_SIZE(buck_voltage_map),
297 .volt_table = buck_voltage_map,
298 .type = REGULATOR_VOLTAGE,
299 .owner = THIS_MODULE,
302 .name = "DCDC2",
303 .id = LP3971_DCDC2,
304 .ops = &lp3971_dcdc_ops,
305 .n_voltages = ARRAY_SIZE(buck_voltage_map),
306 .volt_table = buck_voltage_map,
307 .type = REGULATOR_VOLTAGE,
308 .owner = THIS_MODULE,
311 .name = "DCDC3",
312 .id = LP3971_DCDC3,
313 .ops = &lp3971_dcdc_ops,
314 .n_voltages = ARRAY_SIZE(buck_voltage_map),
315 .volt_table = buck_voltage_map,
316 .type = REGULATOR_VOLTAGE,
317 .owner = THIS_MODULE,
321 static int lp3971_i2c_read(struct i2c_client *i2c, char reg, int count,
322 u16 *dest)
324 int ret;
326 if (count != 1)
327 return -EIO;
328 ret = i2c_smbus_read_byte_data(i2c, reg);
329 if (ret < 0)
330 return ret;
332 *dest = ret;
333 return 0;
336 static int lp3971_i2c_write(struct i2c_client *i2c, char reg, int count,
337 const u16 *src)
339 if (count != 1)
340 return -EIO;
341 return i2c_smbus_write_byte_data(i2c, reg, *src);
344 static u8 lp3971_reg_read(struct lp3971 *lp3971, u8 reg)
346 u16 val = 0;
348 mutex_lock(&lp3971->io_lock);
350 lp3971_i2c_read(lp3971->i2c, reg, 1, &val);
352 dev_dbg(lp3971->dev, "reg read 0x%02x -> 0x%02x\n", (int)reg,
353 (unsigned)val&0xff);
355 mutex_unlock(&lp3971->io_lock);
357 return val & 0xff;
360 static int lp3971_set_bits(struct lp3971 *lp3971, u8 reg, u16 mask, u16 val)
362 u16 tmp;
363 int ret;
365 mutex_lock(&lp3971->io_lock);
367 ret = lp3971_i2c_read(lp3971->i2c, reg, 1, &tmp);
368 if (ret == 0) {
369 tmp = (tmp & ~mask) | val;
370 ret = lp3971_i2c_write(lp3971->i2c, reg, 1, &tmp);
371 dev_dbg(lp3971->dev, "reg write 0x%02x -> 0x%02x\n", (int)reg,
372 (unsigned)val&0xff);
374 mutex_unlock(&lp3971->io_lock);
376 return ret;
379 static int setup_regulators(struct lp3971 *lp3971,
380 struct lp3971_platform_data *pdata)
382 int i, err;
384 /* Instantiate the regulators */
385 for (i = 0; i < pdata->num_regulators; i++) {
386 struct regulator_config config = { };
387 struct lp3971_regulator_subdev *reg = &pdata->regulators[i];
388 struct regulator_dev *rdev;
390 config.dev = lp3971->dev;
391 config.init_data = reg->initdata;
392 config.driver_data = lp3971;
394 rdev = devm_regulator_register(lp3971->dev,
395 &regulators[reg->id], &config);
396 if (IS_ERR(rdev)) {
397 err = PTR_ERR(rdev);
398 dev_err(lp3971->dev, "regulator init failed: %d\n",
399 err);
400 return err;
404 return 0;
407 static int lp3971_i2c_probe(struct i2c_client *i2c,
408 const struct i2c_device_id *id)
410 struct lp3971 *lp3971;
411 struct lp3971_platform_data *pdata = dev_get_platdata(&i2c->dev);
412 int ret;
413 u16 val;
415 if (!pdata) {
416 dev_dbg(&i2c->dev, "No platform init data supplied\n");
417 return -ENODEV;
420 lp3971 = devm_kzalloc(&i2c->dev, sizeof(struct lp3971), GFP_KERNEL);
421 if (lp3971 == NULL)
422 return -ENOMEM;
424 lp3971->i2c = i2c;
425 lp3971->dev = &i2c->dev;
427 mutex_init(&lp3971->io_lock);
429 /* Detect LP3971 */
430 ret = lp3971_i2c_read(i2c, LP3971_SYS_CONTROL1_REG, 1, &val);
431 if (ret == 0 && (val & SYS_CONTROL1_INIT_MASK) != SYS_CONTROL1_INIT_VAL)
432 ret = -ENODEV;
433 if (ret < 0) {
434 dev_err(&i2c->dev, "failed to detect device\n");
435 return ret;
438 ret = setup_regulators(lp3971, pdata);
439 if (ret < 0)
440 return ret;
442 i2c_set_clientdata(i2c, lp3971);
443 return 0;
446 static const struct i2c_device_id lp3971_i2c_id[] = {
447 { "lp3971", 0 },
450 MODULE_DEVICE_TABLE(i2c, lp3971_i2c_id);
452 static struct i2c_driver lp3971_i2c_driver = {
453 .driver = {
454 .name = "LP3971",
456 .probe = lp3971_i2c_probe,
457 .id_table = lp3971_i2c_id,
460 module_i2c_driver(lp3971_i2c_driver);
462 MODULE_LICENSE("GPL");
463 MODULE_AUTHOR("Marek Szyprowski <m.szyprowski@samsung.com>");
464 MODULE_DESCRIPTION("LP3971 PMIC driver");