1/*
2 * TI TPS65132 Regulator driver
3 *
4 * Copyright (C) 2017 NVIDIA CORPORATION. All rights reserved.
5 *
6 * Author: Venkat Reddy Talla <vreddytalla@nvidia.com>
7 *		Laxman Dewangan <ldewangan@nvidia.com>
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation; either version 2 of the
12 * License, or (at your option) any later version.
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
20#include <linux/delay.h>
21#include <linux/err.h>
22#include <linux/gpio/consumer.h>
23#include <linux/i2c.h>
24#include <linux/module.h>
25#include <linux/regmap.h>
26#include <linux/regulator/driver.h>
27#include <linux/regulator/machine.h>
28
29#define TPS65132_REG_VPOS		0x00
30#define TPS65132_REG_VNEG		0x01
31#define TPS65132_REG_APPS_DISP_DISN	0x03
32#define TPS65132_REG_CONTROL		0x0FF
33
34#define TPS65132_VOUT_MASK		0x1F
35#define TPS65132_VOUT_N_VOLTAGE		0x15
36#define TPS65132_VOUT_VMIN		4000000
37#define TPS65132_VOUT_VMAX		6000000
38#define TPS65132_VOUT_STEP		100000
39
40#define TPS65132_REG_APPS_DIS_VPOS		BIT(0)
41#define TPS65132_REG_APPS_DIS_VNEG		BIT(1)
42
43#define TPS65132_REGULATOR_ID_VPOS	0
44#define TPS65132_REGULATOR_ID_VNEG	1
45#define TPS65132_MAX_REGULATORS		2
46
47#define TPS65132_ACT_DIS_TIME_SLACK		1000
48
49struct tps65132_reg_pdata {
50	struct gpio_desc *en_gpiod;
51	struct gpio_desc *act_dis_gpiod;
52	unsigned int act_dis_time_us;
53	int ena_gpio_state;
54};
55
56struct tps65132_regulator {
57	struct device *dev;
58	struct tps65132_reg_pdata reg_pdata[TPS65132_MAX_REGULATORS];
59};
60
61static int tps65132_regulator_enable(struct regulator_dev *rdev)
62{
63	struct tps65132_regulator *tps = rdev_get_drvdata(rdev);
64	int id = rdev_get_id(rdev);
65	struct tps65132_reg_pdata *rpdata = &tps->reg_pdata[id];
66	int ret;
67
68	if (!IS_ERR(rpdata->en_gpiod)) {
69		gpiod_set_value_cansleep(rpdata->en_gpiod, 1);
70		rpdata->ena_gpio_state = 1;
71	}
72
73	/* Hardware automatically enable discharge bit in enable */
74	if (rdev->constraints->active_discharge ==
75			REGULATOR_ACTIVE_DISCHARGE_DISABLE) {
76		ret = regulator_set_active_discharge_regmap(rdev, false);
77		if (ret < 0) {
78			dev_err(tps->dev, "Failed to disable active discharge: %d\n",
79				ret);
80			return ret;
81		}
82	}
83
84	return 0;
85}
86
87static int tps65132_regulator_disable(struct regulator_dev *rdev)
88{
89	struct tps65132_regulator *tps = rdev_get_drvdata(rdev);
90	int id = rdev_get_id(rdev);
91	struct tps65132_reg_pdata *rpdata = &tps->reg_pdata[id];
92
93	if (!IS_ERR(rpdata->en_gpiod)) {
94		gpiod_set_value_cansleep(rpdata->en_gpiod, 0);
95		rpdata->ena_gpio_state = 0;
96	}
97
98	if (!IS_ERR(rpdata->act_dis_gpiod)) {
99		gpiod_set_value_cansleep(rpdata->act_dis_gpiod, 1);
100		usleep_range(rpdata->act_dis_time_us, rpdata->act_dis_time_us +
101			     TPS65132_ACT_DIS_TIME_SLACK);
102		gpiod_set_value_cansleep(rpdata->act_dis_gpiod, 0);
103	}
104
105	return 0;
106}
107
108static int tps65132_regulator_is_enabled(struct regulator_dev *rdev)
109{
110	struct tps65132_regulator *tps = rdev_get_drvdata(rdev);
111	int id = rdev_get_id(rdev);
112	struct tps65132_reg_pdata *rpdata = &tps->reg_pdata[id];
113
114	if (!IS_ERR(rpdata->en_gpiod))
115		return rpdata->ena_gpio_state;
116
117	return 1;
118}
119
120static const struct regulator_ops tps65132_regulator_ops = {
121	.enable = tps65132_regulator_enable,
122	.disable = tps65132_regulator_disable,
123	.is_enabled = tps65132_regulator_is_enabled,
124	.list_voltage = regulator_list_voltage_linear,
125	.map_voltage = regulator_map_voltage_linear,
126	.get_voltage_sel = regulator_get_voltage_sel_regmap,
127	.set_voltage_sel = regulator_set_voltage_sel_regmap,
128	.set_active_discharge = regulator_set_active_discharge_regmap,
129};
130
131static int tps65132_of_parse_cb(struct device_node *np,
132				const struct regulator_desc *desc,
133				struct regulator_config *config)
134{
135	struct tps65132_regulator *tps = config->driver_data;
136	struct tps65132_reg_pdata *rpdata = &tps->reg_pdata[desc->id];
137	int ret;
138
139	rpdata->en_gpiod = devm_fwnode_gpiod_get(tps->dev, of_fwnode_handle(np),
140						 "enable", GPIOD_ASIS,
141						 "enable");
142	if (IS_ERR(rpdata->en_gpiod)) {
143		ret = PTR_ERR(rpdata->en_gpiod);
144
145		/* Ignore the error other than probe defer */
146		if (ret == -EPROBE_DEFER)
147			return ret;
148		return 0;
149	}
150
151	rpdata->act_dis_gpiod = devm_fwnode_gpiod_get(tps->dev,
152						      of_fwnode_handle(np),
153						      "active-discharge",
154						      GPIOD_ASIS,
155						      "active-discharge");
156	if (IS_ERR(rpdata->act_dis_gpiod)) {
157		ret = PTR_ERR(rpdata->act_dis_gpiod);
158
159		/* Ignore the error other than probe defer */
160		if (ret == -EPROBE_DEFER)
161			return ret;
162
163		return 0;
164	}
165
166	ret = of_property_read_u32(np, "ti,active-discharge-time-us",
167				   &rpdata->act_dis_time_us);
168	if (ret < 0) {
169		dev_err(tps->dev, "Failed to read active discharge time:%d\n",
170			ret);
171		return ret;
172	}
173
174	return 0;
175}
176
177#define TPS65132_REGULATOR_DESC(_id, _name)		\
178	[TPS65132_REGULATOR_ID_##_id] = {		\
179		.name = "tps65132-"#_name,		\
180		.supply_name = "vin",			\
181		.id = TPS65132_REGULATOR_ID_##_id,	\
182		.of_match = of_match_ptr(#_name),	\
183		.of_parse_cb	= tps65132_of_parse_cb,	\
184		.ops = &tps65132_regulator_ops,		\
185		.n_voltages = TPS65132_VOUT_N_VOLTAGE,	\
186		.min_uV = TPS65132_VOUT_VMIN,		\
187		.uV_step = TPS65132_VOUT_STEP,		\
188		.enable_time = 500,			\
189		.vsel_mask = TPS65132_VOUT_MASK,	\
190		.vsel_reg = TPS65132_REG_##_id,		\
191		.active_discharge_off = 0,			\
192		.active_discharge_on = TPS65132_REG_APPS_DIS_##_id, \
193		.active_discharge_mask = TPS65132_REG_APPS_DIS_##_id, \
194		.active_discharge_reg = TPS65132_REG_APPS_DISP_DISN, \
195		.type = REGULATOR_VOLTAGE,		\
196		.owner = THIS_MODULE,			\
197	}
198
199static const struct regulator_desc tps_regs_desc[TPS65132_MAX_REGULATORS] = {
200	TPS65132_REGULATOR_DESC(VPOS, outp),
201	TPS65132_REGULATOR_DESC(VNEG, outn),
202};
203
204static const struct regmap_range tps65132_no_reg_ranges[] = {
205	regmap_reg_range(TPS65132_REG_APPS_DISP_DISN + 1,
206			 TPS65132_REG_CONTROL - 1),
207};
208
209static const struct regmap_access_table tps65132_no_reg_table = {
210	.no_ranges = tps65132_no_reg_ranges,
211	.n_no_ranges = ARRAY_SIZE(tps65132_no_reg_ranges),
212};
213
214static const struct regmap_config tps65132_regmap_config = {
215	.reg_bits	= 8,
216	.val_bits	= 8,
217	.max_register	= TPS65132_REG_CONTROL,
218	.cache_type	= REGCACHE_NONE,
219	.rd_table	= &tps65132_no_reg_table,
220	.wr_table	= &tps65132_no_reg_table,
221};
222
223static int tps65132_probe(struct i2c_client *client)
224{
225	struct device *dev = &client->dev;
226	struct tps65132_regulator *tps;
227	struct regulator_dev *rdev;
228	struct regmap *rmap;
229	struct regulator_config config = { };
230	int id;
231	int ret;
232
233	tps = devm_kzalloc(dev, sizeof(*tps), GFP_KERNEL);
234	if (!tps)
235		return -ENOMEM;
236
237	rmap = devm_regmap_init_i2c(client, &tps65132_regmap_config);
238	if (IS_ERR(rmap)) {
239		ret = PTR_ERR(rmap);
240		dev_err(dev, "regmap init failed: %d\n", ret);
241		return ret;
242	}
243
244	i2c_set_clientdata(client, tps);
245	tps->dev = dev;
246
247	for (id = 0; id < TPS65132_MAX_REGULATORS; ++id) {
248		config.regmap = rmap;
249		config.dev = dev;
250		config.driver_data = tps;
251
252		rdev = devm_regulator_register(dev, &tps_regs_desc[id],
253					       &config);
254		if (IS_ERR(rdev)) {
255			ret = PTR_ERR(rdev);
256			dev_err(dev, "regulator %s register failed: %d\n",
257				tps_regs_desc[id].name, ret);
258			return ret;
259		}
260	}
261	return 0;
262}
263
264static const struct i2c_device_id tps65132_id[] = {
265	{.name = "tps65132",},
266	{},
267};
268MODULE_DEVICE_TABLE(i2c, tps65132_id);
269
270static const struct of_device_id __maybe_unused tps65132_of_match[] = {
271	{ .compatible = "ti,tps65132" },
272	{},
273};
274MODULE_DEVICE_TABLE(of, tps65132_of_match);
275
276static struct i2c_driver tps65132_i2c_driver = {
277	.driver = {
278		.name = "tps65132",
279		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
280		.of_match_table = of_match_ptr(tps65132_of_match),
281	},
282	.probe = tps65132_probe,
283	.id_table = tps65132_id,
284};
285
286module_i2c_driver(tps65132_i2c_driver);
287
288MODULE_DESCRIPTION("tps65132 regulator driver");
289MODULE_AUTHOR("Venkat Reddy Talla <vreddytalla@nvidia.com>");
290MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
291MODULE_LICENSE("GPL v2");
292