1/*
2 * Regulator driver for National Semiconductors LP3972 PMIC chip
3 *
4 * Based on lp3971.c
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 */
11
12#include <linux/bug.h>
13#include <linux/err.h>
14#include <linux/i2c.h>
15#include <linux/module.h>
16#include <linux/kernel.h>
17#include <linux/regulator/driver.h>
18#include <linux/regulator/lp3972.h>
19#include <linux/slab.h>
20
21struct lp3972 {
22	struct device *dev;
23	struct mutex io_lock;
24	struct i2c_client *i2c;
25};
26
27/* LP3972 Control Registers */
28#define LP3972_SCR_REG		0x07
29#define LP3972_OVER1_REG	0x10
30#define LP3972_OVSR1_REG	0x11
31#define LP3972_OVER2_REG	0x12
32#define LP3972_OVSR2_REG	0x13
33#define LP3972_VCC1_REG		0x20
34#define LP3972_ADTV1_REG	0x23
35#define LP3972_ADTV2_REG	0x24
36#define LP3972_AVRC_REG		0x25
37#define LP3972_CDTC1_REG	0x26
38#define LP3972_CDTC2_REG	0x27
39#define LP3972_SDTV1_REG	0x29
40#define LP3972_SDTV2_REG	0x2A
41#define LP3972_MDTV1_REG	0x32
42#define LP3972_MDTV2_REG	0x33
43#define LP3972_L2VCR_REG	0x39
44#define LP3972_L34VCR_REG	0x3A
45#define LP3972_SCR1_REG		0x80
46#define LP3972_SCR2_REG		0x81
47#define LP3972_OEN3_REG		0x82
48#define LP3972_OSR3_REG		0x83
49#define LP3972_LOER4_REG	0x84
50#define LP3972_B2TV_REG		0x85
51#define LP3972_B3TV_REG		0x86
52#define LP3972_B32RC_REG	0x87
53#define LP3972_ISRA_REG		0x88
54#define LP3972_BCCR_REG		0x89
55#define LP3972_II1RR_REG	0x8E
56#define LP3972_II2RR_REG	0x8F
57
58#define LP3972_SYS_CONTROL1_REG		LP3972_SCR1_REG
59/* System control register 1 initial value,
60 * bits 5, 6 and 7 are EPROM programmable */
61#define SYS_CONTROL1_INIT_VAL		0x02
62#define SYS_CONTROL1_INIT_MASK		0x1F
63
64#define LP3972_VOL_CHANGE_REG		LP3972_VCC1_REG
65#define LP3972_VOL_CHANGE_FLAG_GO	0x01
66#define LP3972_VOL_CHANGE_FLAG_MASK	0x03
67
68/* LDO output enable mask */
69#define LP3972_OEN3_L1EN	BIT(0)
70#define LP3972_OVER2_LDO2_EN	BIT(2)
71#define LP3972_OVER2_LDO3_EN	BIT(3)
72#define LP3972_OVER2_LDO4_EN	BIT(4)
73#define LP3972_OVER1_S_EN	BIT(2)
74
75static const unsigned int ldo1_voltage_map[] = {
76	1700000, 1725000, 1750000, 1775000, 1800000, 1825000, 1850000, 1875000,
77	1900000, 1925000, 1950000, 1975000, 2000000,
78};
79
80static const unsigned int ldo23_voltage_map[] = {
81	1800000, 1900000, 2000000, 2100000, 2200000, 2300000, 2400000, 2500000,
82	2600000, 2700000, 2800000, 2900000, 3000000, 3100000, 3200000, 3300000,
83};
84
85static const unsigned int ldo4_voltage_map[] = {
86	1000000, 1050000, 1100000, 1150000, 1200000, 1250000, 1300000, 1350000,
87	1400000, 1500000, 1800000, 1900000, 2500000, 2800000, 3000000, 3300000,
88};
89
90static const unsigned int ldo5_voltage_map[] = {
91	      0,       0,       0,       0,       0,  850000,  875000,  900000,
92	 925000,  950000,  975000, 1000000, 1025000, 1050000, 1075000, 1100000,
93	1125000, 1150000, 1175000, 1200000, 1225000, 1250000, 1275000, 1300000,
94	1325000, 1350000, 1375000, 1400000, 1425000, 1450000, 1475000, 1500000,
95};
96
97static const unsigned int buck1_voltage_map[] = {
98	 725000,  750000,  775000,  800000,  825000,  850000,  875000,  900000,
99	 925000,  950000,  975000, 1000000, 1025000, 1050000, 1075000, 1100000,
100	1125000, 1150000, 1175000, 1200000, 1225000, 1250000, 1275000, 1300000,
101	1325000, 1350000, 1375000, 1400000, 1425000, 1450000, 1475000, 1500000,
102};
103
104static const unsigned int buck23_voltage_map[] = {
105	      0,  800000,  850000,  900000,  950000, 1000000, 1050000, 1100000,
106	1150000, 1200000, 1250000, 1300000, 1350000, 1400000, 1450000, 1500000,
107	1550000, 1600000, 1650000, 1700000, 1800000, 1900000, 2500000, 2800000,
108	3000000, 3300000,
109};
110
111static const int ldo_output_enable_mask[] = {
112	LP3972_OEN3_L1EN,
113	LP3972_OVER2_LDO2_EN,
114	LP3972_OVER2_LDO3_EN,
115	LP3972_OVER2_LDO4_EN,
116	LP3972_OVER1_S_EN,
117};
118
119static const int ldo_output_enable_addr[] = {
120	LP3972_OEN3_REG,
121	LP3972_OVER2_REG,
122	LP3972_OVER2_REG,
123	LP3972_OVER2_REG,
124	LP3972_OVER1_REG,
125};
126
127static const int ldo_vol_ctl_addr[] = {
128	LP3972_MDTV1_REG,
129	LP3972_L2VCR_REG,
130	LP3972_L34VCR_REG,
131	LP3972_L34VCR_REG,
132	LP3972_SDTV1_REG,
133};
134
135static const int buck_vol_enable_addr[] = {
136	LP3972_OVER1_REG,
137	LP3972_OEN3_REG,
138	LP3972_OEN3_REG,
139};
140
141static const int buck_base_addr[] = {
142	LP3972_ADTV1_REG,
143	LP3972_B2TV_REG,
144	LP3972_B3TV_REG,
145};
146
147#define LP3972_LDO_OUTPUT_ENABLE_MASK(x) (ldo_output_enable_mask[x])
148#define LP3972_LDO_OUTPUT_ENABLE_REG(x) (ldo_output_enable_addr[x])
149
150/*	LDO voltage control registers shift:
151	LP3972_LDO1 -> 0, LP3972_LDO2 -> 4
152	LP3972_LDO3 -> 0, LP3972_LDO4 -> 4
153	LP3972_LDO5 -> 0
154*/
155#define LP3972_LDO_VOL_CONTR_SHIFT(x) (((x) & 1) << 2)
156#define LP3972_LDO_VOL_CONTR_REG(x) (ldo_vol_ctl_addr[x])
157#define LP3972_LDO_VOL_CHANGE_SHIFT(x) ((x) ? 4 : 6)
158
159#define LP3972_LDO_VOL_MASK(x) (((x) % 4) ? 0x0f : 0x1f)
160#define LP3972_LDO_VOL_MIN_IDX(x) (((x) == 4) ? 0x05 : 0x00)
161#define LP3972_LDO_VOL_MAX_IDX(x) ((x) ? (((x) == 4) ? 0x1f : 0x0f) : 0x0c)
162
163#define LP3972_BUCK_VOL_ENABLE_REG(x) (buck_vol_enable_addr[x])
164#define LP3972_BUCK_VOL1_REG(x) (buck_base_addr[x])
165#define LP3972_BUCK_VOL_MASK 0x1f
166
167static int lp3972_i2c_read(struct i2c_client *i2c, char reg, int count,
168	u16 *dest)
169{
170	int ret;
171
172	if (count != 1)
173		return -EIO;
174	ret = i2c_smbus_read_byte_data(i2c, reg);
175	if (ret < 0)
176		return ret;
177
178	*dest = ret;
179	return 0;
180}
181
182static int lp3972_i2c_write(struct i2c_client *i2c, char reg, int count,
183	const u16 *src)
184{
185	if (count != 1)
186		return -EIO;
187	return i2c_smbus_write_byte_data(i2c, reg, *src);
188}
189
190static u8 lp3972_reg_read(struct lp3972 *lp3972, u8 reg)
191{
192	u16 val = 0;
193
194	mutex_lock(&lp3972->io_lock);
195
196	lp3972_i2c_read(lp3972->i2c, reg, 1, &val);
197
198	dev_dbg(lp3972->dev, "reg read 0x%02x -> 0x%02x\n", (int)reg,
199		(unsigned)val & 0xff);
200
201	mutex_unlock(&lp3972->io_lock);
202
203	return val & 0xff;
204}
205
206static int lp3972_set_bits(struct lp3972 *lp3972, u8 reg, u16 mask, u16 val)
207{
208	u16 tmp;
209	int ret;
210
211	mutex_lock(&lp3972->io_lock);
212
213	ret = lp3972_i2c_read(lp3972->i2c, reg, 1, &tmp);
214	tmp = (tmp & ~mask) | val;
215	if (ret == 0) {
216		ret = lp3972_i2c_write(lp3972->i2c, reg, 1, &tmp);
217		dev_dbg(lp3972->dev, "reg write 0x%02x -> 0x%02x\n", (int)reg,
218			(unsigned)val & 0xff);
219	}
220	mutex_unlock(&lp3972->io_lock);
221
222	return ret;
223}
224
225static int lp3972_ldo_is_enabled(struct regulator_dev *dev)
226{
227	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
228	int ldo = rdev_get_id(dev) - LP3972_LDO1;
229	u16 mask = LP3972_LDO_OUTPUT_ENABLE_MASK(ldo);
230	u16 val;
231
232	val = lp3972_reg_read(lp3972, LP3972_LDO_OUTPUT_ENABLE_REG(ldo));
233	return !!(val & mask);
234}
235
236static int lp3972_ldo_enable(struct regulator_dev *dev)
237{
238	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
239	int ldo = rdev_get_id(dev) - LP3972_LDO1;
240	u16 mask = LP3972_LDO_OUTPUT_ENABLE_MASK(ldo);
241
242	return lp3972_set_bits(lp3972, LP3972_LDO_OUTPUT_ENABLE_REG(ldo),
243				mask, mask);
244}
245
246static int lp3972_ldo_disable(struct regulator_dev *dev)
247{
248	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
249	int ldo = rdev_get_id(dev) - LP3972_LDO1;
250	u16 mask = LP3972_LDO_OUTPUT_ENABLE_MASK(ldo);
251
252	return lp3972_set_bits(lp3972, LP3972_LDO_OUTPUT_ENABLE_REG(ldo),
253				mask, 0);
254}
255
256static int lp3972_ldo_get_voltage_sel(struct regulator_dev *dev)
257{
258	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
259	int ldo = rdev_get_id(dev) - LP3972_LDO1;
260	u16 mask = LP3972_LDO_VOL_MASK(ldo);
261	u16 val, reg;
262
263	reg = lp3972_reg_read(lp3972, LP3972_LDO_VOL_CONTR_REG(ldo));
264	val = (reg >> LP3972_LDO_VOL_CONTR_SHIFT(ldo)) & mask;
265
266	return val;
267}
268
269static int lp3972_ldo_set_voltage_sel(struct regulator_dev *dev,
270				      unsigned int selector)
271{
272	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
273	int ldo = rdev_get_id(dev) - LP3972_LDO1;
274	int shift, ret;
275
276	shift = LP3972_LDO_VOL_CONTR_SHIFT(ldo);
277	ret = lp3972_set_bits(lp3972, LP3972_LDO_VOL_CONTR_REG(ldo),
278		LP3972_LDO_VOL_MASK(ldo) << shift, selector << shift);
279
280	if (ret)
281		return ret;
282
283	/*
284	 * LDO1 and LDO5 support voltage control by either target voltage1
285	 * or target voltage2 register.
286	 * We use target voltage1 register for LDO1 and LDO5 in this driver.
287	 * We need to update voltage change control register(0x20) to enable
288	 * LDO1 and LDO5 to change to their programmed target values.
289	 */
290	switch (ldo) {
291	case LP3972_LDO1:
292	case LP3972_LDO5:
293		shift = LP3972_LDO_VOL_CHANGE_SHIFT(ldo);
294		ret = lp3972_set_bits(lp3972, LP3972_VOL_CHANGE_REG,
295			LP3972_VOL_CHANGE_FLAG_MASK << shift,
296			LP3972_VOL_CHANGE_FLAG_GO << shift);
297		if (ret)
298			return ret;
299
300		ret = lp3972_set_bits(lp3972, LP3972_VOL_CHANGE_REG,
301			LP3972_VOL_CHANGE_FLAG_MASK << shift, 0);
302		break;
303	}
304
305	return ret;
306}
307
308static struct regulator_ops lp3972_ldo_ops = {
309	.list_voltage = regulator_list_voltage_table,
310	.map_voltage = regulator_map_voltage_ascend,
311	.is_enabled = lp3972_ldo_is_enabled,
312	.enable = lp3972_ldo_enable,
313	.disable = lp3972_ldo_disable,
314	.get_voltage_sel = lp3972_ldo_get_voltage_sel,
315	.set_voltage_sel = lp3972_ldo_set_voltage_sel,
316};
317
318static int lp3972_dcdc_is_enabled(struct regulator_dev *dev)
319{
320	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
321	int buck = rdev_get_id(dev) - LP3972_DCDC1;
322	u16 mask = 1 << (buck * 2);
323	u16 val;
324
325	val = lp3972_reg_read(lp3972, LP3972_BUCK_VOL_ENABLE_REG(buck));
326	return !!(val & mask);
327}
328
329static int lp3972_dcdc_enable(struct regulator_dev *dev)
330{
331	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
332	int buck = rdev_get_id(dev) - LP3972_DCDC1;
333	u16 mask = 1 << (buck * 2);
334	u16 val;
335
336	val = lp3972_set_bits(lp3972, LP3972_BUCK_VOL_ENABLE_REG(buck),
337				mask, mask);
338	return val;
339}
340
341static int lp3972_dcdc_disable(struct regulator_dev *dev)
342{
343	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
344	int buck = rdev_get_id(dev) - LP3972_DCDC1;
345	u16 mask = 1 << (buck * 2);
346	u16 val;
347
348	val = lp3972_set_bits(lp3972, LP3972_BUCK_VOL_ENABLE_REG(buck),
349				mask, 0);
350	return val;
351}
352
353static int lp3972_dcdc_get_voltage_sel(struct regulator_dev *dev)
354{
355	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
356	int buck = rdev_get_id(dev) - LP3972_DCDC1;
357	u16 reg;
358
359	reg = lp3972_reg_read(lp3972, LP3972_BUCK_VOL1_REG(buck));
360	reg &= LP3972_BUCK_VOL_MASK;
361
362	return reg;
363}
364
365static int lp3972_dcdc_set_voltage_sel(struct regulator_dev *dev,
366				       unsigned int selector)
367{
368	struct lp3972 *lp3972 = rdev_get_drvdata(dev);
369	int buck = rdev_get_id(dev) - LP3972_DCDC1;
370	int ret;
371
372	ret = lp3972_set_bits(lp3972, LP3972_BUCK_VOL1_REG(buck),
373				LP3972_BUCK_VOL_MASK, selector);
374	if (ret)
375		return ret;
376
377	if (buck != 0)
378		return ret;
379
380	ret = lp3972_set_bits(lp3972, LP3972_VOL_CHANGE_REG,
381		LP3972_VOL_CHANGE_FLAG_MASK, LP3972_VOL_CHANGE_FLAG_GO);
382	if (ret)
383		return ret;
384
385	return lp3972_set_bits(lp3972, LP3972_VOL_CHANGE_REG,
386				LP3972_VOL_CHANGE_FLAG_MASK, 0);
387}
388
389static struct regulator_ops lp3972_dcdc_ops = {
390	.list_voltage = regulator_list_voltage_table,
391	.map_voltage = regulator_map_voltage_ascend,
392	.is_enabled = lp3972_dcdc_is_enabled,
393	.enable = lp3972_dcdc_enable,
394	.disable = lp3972_dcdc_disable,
395	.get_voltage_sel = lp3972_dcdc_get_voltage_sel,
396	.set_voltage_sel = lp3972_dcdc_set_voltage_sel,
397};
398
399static const struct regulator_desc regulators[] = {
400	{
401		.name = "LDO1",
402		.id = LP3972_LDO1,
403		.ops = &lp3972_ldo_ops,
404		.n_voltages = ARRAY_SIZE(ldo1_voltage_map),
405		.volt_table = ldo1_voltage_map,
406		.type = REGULATOR_VOLTAGE,
407		.owner = THIS_MODULE,
408	},
409	{
410		.name = "LDO2",
411		.id = LP3972_LDO2,
412		.ops = &lp3972_ldo_ops,
413		.n_voltages = ARRAY_SIZE(ldo23_voltage_map),
414		.volt_table = ldo23_voltage_map,
415		.type = REGULATOR_VOLTAGE,
416		.owner = THIS_MODULE,
417	},
418	{
419		.name = "LDO3",
420		.id = LP3972_LDO3,
421		.ops = &lp3972_ldo_ops,
422		.n_voltages = ARRAY_SIZE(ldo23_voltage_map),
423		.volt_table = ldo23_voltage_map,
424		.type = REGULATOR_VOLTAGE,
425		.owner = THIS_MODULE,
426	},
427	{
428		.name = "LDO4",
429		.id = LP3972_LDO4,
430		.ops = &lp3972_ldo_ops,
431		.n_voltages = ARRAY_SIZE(ldo4_voltage_map),
432		.volt_table = ldo4_voltage_map,
433		.type = REGULATOR_VOLTAGE,
434		.owner = THIS_MODULE,
435	},
436	{
437		.name = "LDO5",
438		.id = LP3972_LDO5,
439		.ops = &lp3972_ldo_ops,
440		.n_voltages = ARRAY_SIZE(ldo5_voltage_map),
441		.volt_table = ldo5_voltage_map,
442		.type = REGULATOR_VOLTAGE,
443		.owner = THIS_MODULE,
444	},
445	{
446		.name = "DCDC1",
447		.id = LP3972_DCDC1,
448		.ops = &lp3972_dcdc_ops,
449		.n_voltages = ARRAY_SIZE(buck1_voltage_map),
450		.volt_table = buck1_voltage_map,
451		.type = REGULATOR_VOLTAGE,
452		.owner = THIS_MODULE,
453	},
454	{
455		.name = "DCDC2",
456		.id = LP3972_DCDC2,
457		.ops = &lp3972_dcdc_ops,
458		.n_voltages = ARRAY_SIZE(buck23_voltage_map),
459		.volt_table = buck23_voltage_map,
460		.type = REGULATOR_VOLTAGE,
461		.owner = THIS_MODULE,
462	},
463	{
464		.name = "DCDC3",
465		.id = LP3972_DCDC3,
466		.ops = &lp3972_dcdc_ops,
467		.n_voltages = ARRAY_SIZE(buck23_voltage_map),
468		.volt_table = buck23_voltage_map,
469		.type = REGULATOR_VOLTAGE,
470		.owner = THIS_MODULE,
471	},
472};
473
474static int setup_regulators(struct lp3972 *lp3972,
475	struct lp3972_platform_data *pdata)
476{
477	int i, err;
478
479	/* Instantiate the regulators */
480	for (i = 0; i < pdata->num_regulators; i++) {
481		struct lp3972_regulator_subdev *reg = &pdata->regulators[i];
482		struct regulator_config config = { };
483		struct regulator_dev *rdev;
484
485		config.dev = lp3972->dev;
486		config.init_data = reg->initdata;
487		config.driver_data = lp3972;
488
489		rdev = devm_regulator_register(lp3972->dev,
490					       &regulators[reg->id], &config);
491		if (IS_ERR(rdev)) {
492			err = PTR_ERR(rdev);
493			dev_err(lp3972->dev, "regulator init failed: %d\n",
494				err);
495			return err;
496		}
497	}
498
499	return 0;
500}
501
502static int lp3972_i2c_probe(struct i2c_client *i2c,
503			    const struct i2c_device_id *id)
504{
505	struct lp3972 *lp3972;
506	struct lp3972_platform_data *pdata = dev_get_platdata(&i2c->dev);
507	int ret;
508	u16 val;
509
510	if (!pdata) {
511		dev_dbg(&i2c->dev, "No platform init data supplied\n");
512		return -ENODEV;
513	}
514
515	lp3972 = devm_kzalloc(&i2c->dev, sizeof(struct lp3972), GFP_KERNEL);
516	if (!lp3972)
517		return -ENOMEM;
518
519	lp3972->i2c = i2c;
520	lp3972->dev = &i2c->dev;
521
522	mutex_init(&lp3972->io_lock);
523
524	/* Detect LP3972 */
525	ret = lp3972_i2c_read(i2c, LP3972_SYS_CONTROL1_REG, 1, &val);
526	if (ret == 0 &&
527		(val & SYS_CONTROL1_INIT_MASK) != SYS_CONTROL1_INIT_VAL) {
528		ret = -ENODEV;
529		dev_err(&i2c->dev, "chip reported: val = 0x%x\n", val);
530	}
531	if (ret < 0) {
532		dev_err(&i2c->dev, "failed to detect device. ret = %d\n", ret);
533		return ret;
534	}
535
536	ret = setup_regulators(lp3972, pdata);
537	if (ret < 0)
538		return ret;
539
540	i2c_set_clientdata(i2c, lp3972);
541	return 0;
542}
543
544static const struct i2c_device_id lp3972_i2c_id[] = {
545	{ "lp3972", 0 },
546	{ }
547};
548MODULE_DEVICE_TABLE(i2c, lp3972_i2c_id);
549
550static struct i2c_driver lp3972_i2c_driver = {
551	.driver = {
552		.name = "lp3972",
553	},
554	.probe    = lp3972_i2c_probe,
555	.id_table = lp3972_i2c_id,
556};
557
558static int __init lp3972_module_init(void)
559{
560	return i2c_add_driver(&lp3972_i2c_driver);
561}
562subsys_initcall(lp3972_module_init);
563
564static void __exit lp3972_module_exit(void)
565{
566	i2c_del_driver(&lp3972_i2c_driver);
567}
568module_exit(lp3972_module_exit);
569
570MODULE_LICENSE("GPL");
571MODULE_AUTHOR("Axel Lin <axel.lin@gmail.com>");
572MODULE_DESCRIPTION("LP3972 PMIC driver");
573