1 /*
2  * TI LM363X Regulator Driver
3  *
4  * Copyright 2015 Texas Instruments
5  *
6  * Author: Milo Kim <milo.kim@ti.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #include <linux/err.h>
14 #include <linux/kernel.h>
15 #include <linux/mfd/ti-lmu.h>
16 #include <linux/mfd/ti-lmu-register.h>
17 #include <linux/module.h>
18 #include <linux/of.h>
19 #include <linux/gpio/consumer.h>
20 #include <linux/platform_device.h>
21 #include <linux/regulator/driver.h>
22 #include <linux/regulator/of_regulator.h>
23 #include <linux/slab.h>
24 
25 /* LM3631 */
26 #define LM3631_BOOST_VSEL_MAX		0x25
27 #define LM3631_LDO_VSEL_MAX		0x28
28 #define LM3631_CONT_VSEL_MAX		0x03
29 #define LM3631_VBOOST_MIN		4500000
30 #define LM3631_VCONT_MIN		1800000
31 #define LM3631_VLDO_MIN			4000000
32 #define ENABLE_TIME_USEC		1000
33 
34 /* LM3632 */
35 #define LM3632_BOOST_VSEL_MAX		0x26
36 #define LM3632_LDO_VSEL_MAX		0x29
37 #define LM3632_VBOOST_MIN		4500000
38 #define LM3632_VLDO_MIN			4000000
39 
40 /* Common */
41 #define LM363X_STEP_50mV		50000
42 #define LM363X_STEP_500mV		500000
43 
44 static const int ldo_cont_enable_time[] = {
45 	0, 2000, 5000, 10000, 20000, 50000, 100000, 200000,
46 };
47 
48 static int lm363x_regulator_enable_time(struct regulator_dev *rdev)
49 {
50 	enum lm363x_regulator_id id = rdev_get_id(rdev);
51 	u8 val, addr, mask;
52 
53 	switch (id) {
54 	case LM3631_LDO_CONT:
55 		addr = LM3631_REG_ENTIME_VCONT;
56 		mask = LM3631_ENTIME_CONT_MASK;
57 		break;
58 	case LM3631_LDO_OREF:
59 		addr = LM3631_REG_ENTIME_VOREF;
60 		mask = LM3631_ENTIME_MASK;
61 		break;
62 	case LM3631_LDO_POS:
63 		addr = LM3631_REG_ENTIME_VPOS;
64 		mask = LM3631_ENTIME_MASK;
65 		break;
66 	case LM3631_LDO_NEG:
67 		addr = LM3631_REG_ENTIME_VNEG;
68 		mask = LM3631_ENTIME_MASK;
69 		break;
70 	default:
71 		return 0;
72 	}
73 
74 	if (regmap_read(rdev->regmap, addr, (unsigned int *)&val))
75 		return -EINVAL;
76 
77 	val = (val & mask) >> LM3631_ENTIME_SHIFT;
78 
79 	if (id == LM3631_LDO_CONT)
80 		return ldo_cont_enable_time[val];
81 	else
82 		return ENABLE_TIME_USEC * val;
83 }
84 
85 static struct regulator_ops lm363x_boost_voltage_table_ops = {
86 	.list_voltage     = regulator_list_voltage_linear,
87 	.set_voltage_sel  = regulator_set_voltage_sel_regmap,
88 	.get_voltage_sel  = regulator_get_voltage_sel_regmap,
89 };
90 
91 static struct regulator_ops lm363x_regulator_voltage_table_ops = {
92 	.list_voltage     = regulator_list_voltage_linear,
93 	.set_voltage_sel  = regulator_set_voltage_sel_regmap,
94 	.get_voltage_sel  = regulator_get_voltage_sel_regmap,
95 	.enable           = regulator_enable_regmap,
96 	.disable          = regulator_disable_regmap,
97 	.is_enabled       = regulator_is_enabled_regmap,
98 	.enable_time      = lm363x_regulator_enable_time,
99 };
100 
101 static const struct regulator_desc lm363x_regulator_desc[] = {
102 	/* LM3631 */
103 	{
104 		.name           = "vboost",
105 		.of_match	= "vboost",
106 		.id             = LM3631_BOOST,
107 		.ops            = &lm363x_boost_voltage_table_ops,
108 		.n_voltages     = LM3631_BOOST_VSEL_MAX + 1,
109 		.min_uV         = LM3631_VBOOST_MIN,
110 		.uV_step        = LM363X_STEP_50mV,
111 		.type           = REGULATOR_VOLTAGE,
112 		.owner          = THIS_MODULE,
113 		.vsel_reg       = LM3631_REG_VOUT_BOOST,
114 		.vsel_mask      = LM3631_VOUT_MASK,
115 	},
116 	{
117 		.name           = "ldo_cont",
118 		.of_match	= "vcont",
119 		.id             = LM3631_LDO_CONT,
120 		.ops            = &lm363x_regulator_voltage_table_ops,
121 		.n_voltages     = LM3631_CONT_VSEL_MAX + 1,
122 		.min_uV         = LM3631_VCONT_MIN,
123 		.uV_step        = LM363X_STEP_500mV,
124 		.type           = REGULATOR_VOLTAGE,
125 		.owner          = THIS_MODULE,
126 		.vsel_reg       = LM3631_REG_VOUT_CONT,
127 		.vsel_mask      = LM3631_VOUT_CONT_MASK,
128 		.enable_reg     = LM3631_REG_LDO_CTRL2,
129 		.enable_mask    = LM3631_EN_CONT_MASK,
130 	},
131 	{
132 		.name           = "ldo_oref",
133 		.of_match	= "voref",
134 		.id             = LM3631_LDO_OREF,
135 		.ops            = &lm363x_regulator_voltage_table_ops,
136 		.n_voltages     = LM3631_LDO_VSEL_MAX + 1,
137 		.min_uV         = LM3631_VLDO_MIN,
138 		.uV_step        = LM363X_STEP_50mV,
139 		.type           = REGULATOR_VOLTAGE,
140 		.owner          = THIS_MODULE,
141 		.vsel_reg       = LM3631_REG_VOUT_OREF,
142 		.vsel_mask      = LM3631_VOUT_MASK,
143 		.enable_reg     = LM3631_REG_LDO_CTRL1,
144 		.enable_mask    = LM3631_EN_OREF_MASK,
145 	},
146 	{
147 		.name           = "ldo_vpos",
148 		.of_match	= "vpos",
149 		.id             = LM3631_LDO_POS,
150 		.ops            = &lm363x_regulator_voltage_table_ops,
151 		.n_voltages     = LM3631_LDO_VSEL_MAX + 1,
152 		.min_uV         = LM3631_VLDO_MIN,
153 		.uV_step        = LM363X_STEP_50mV,
154 		.type           = REGULATOR_VOLTAGE,
155 		.owner          = THIS_MODULE,
156 		.vsel_reg       = LM3631_REG_VOUT_POS,
157 		.vsel_mask      = LM3631_VOUT_MASK,
158 		.enable_reg     = LM3631_REG_LDO_CTRL1,
159 		.enable_mask    = LM3631_EN_VPOS_MASK,
160 	},
161 	{
162 		.name           = "ldo_vneg",
163 		.of_match	= "vneg",
164 		.id             = LM3631_LDO_NEG,
165 		.ops            = &lm363x_regulator_voltage_table_ops,
166 		.n_voltages     = LM3631_LDO_VSEL_MAX + 1,
167 		.min_uV         = LM3631_VLDO_MIN,
168 		.uV_step        = LM363X_STEP_50mV,
169 		.type           = REGULATOR_VOLTAGE,
170 		.owner          = THIS_MODULE,
171 		.vsel_reg       = LM3631_REG_VOUT_NEG,
172 		.vsel_mask      = LM3631_VOUT_MASK,
173 		.enable_reg     = LM3631_REG_LDO_CTRL1,
174 		.enable_mask    = LM3631_EN_VNEG_MASK,
175 	},
176 	/* LM3632 */
177 	{
178 		.name           = "vboost",
179 		.of_match	= "vboost",
180 		.id             = LM3632_BOOST,
181 		.ops            = &lm363x_boost_voltage_table_ops,
182 		.n_voltages     = LM3632_BOOST_VSEL_MAX + 1,
183 		.min_uV         = LM3632_VBOOST_MIN,
184 		.uV_step        = LM363X_STEP_50mV,
185 		.type           = REGULATOR_VOLTAGE,
186 		.owner          = THIS_MODULE,
187 		.vsel_reg       = LM3632_REG_VOUT_BOOST,
188 		.vsel_mask      = LM3632_VOUT_MASK,
189 	},
190 	{
191 		.name           = "ldo_vpos",
192 		.of_match	= "vpos",
193 		.id             = LM3632_LDO_POS,
194 		.ops            = &lm363x_regulator_voltage_table_ops,
195 		.n_voltages     = LM3632_LDO_VSEL_MAX + 1,
196 		.min_uV         = LM3632_VLDO_MIN,
197 		.uV_step        = LM363X_STEP_50mV,
198 		.type           = REGULATOR_VOLTAGE,
199 		.owner          = THIS_MODULE,
200 		.vsel_reg       = LM3632_REG_VOUT_POS,
201 		.vsel_mask      = LM3632_VOUT_MASK,
202 		.enable_reg     = LM3632_REG_BIAS_CONFIG,
203 		.enable_mask    = LM3632_EN_VPOS_MASK,
204 	},
205 	{
206 		.name           = "ldo_vneg",
207 		.of_match	= "vneg",
208 		.id             = LM3632_LDO_NEG,
209 		.ops            = &lm363x_regulator_voltage_table_ops,
210 		.n_voltages     = LM3632_LDO_VSEL_MAX + 1,
211 		.min_uV         = LM3632_VLDO_MIN,
212 		.uV_step        = LM363X_STEP_50mV,
213 		.type           = REGULATOR_VOLTAGE,
214 		.owner          = THIS_MODULE,
215 		.vsel_reg       = LM3632_REG_VOUT_NEG,
216 		.vsel_mask      = LM3632_VOUT_MASK,
217 		.enable_reg     = LM3632_REG_BIAS_CONFIG,
218 		.enable_mask    = LM3632_EN_VNEG_MASK,
219 	},
220 };
221 
222 static struct gpio_desc *lm363x_regulator_of_get_enable_gpio(struct device *dev, int id)
223 {
224 	/*
225 	 * Check LCM_EN1/2_GPIO is configured.
226 	 * Those pins are used for enabling VPOS/VNEG LDOs.
227 	 * Do not use devm* here: the regulator core takes over the
228 	 * lifecycle management of the GPIO descriptor.
229 	 */
230 	switch (id) {
231 	case LM3632_LDO_POS:
232 		return gpiod_get_index_optional(dev, "enable", 0,
233 				GPIOD_OUT_LOW | GPIOD_FLAGS_BIT_NONEXCLUSIVE);
234 	case LM3632_LDO_NEG:
235 		return gpiod_get_index_optional(dev, "enable", 1,
236 				GPIOD_OUT_LOW | GPIOD_FLAGS_BIT_NONEXCLUSIVE);
237 	default:
238 		return NULL;
239 	}
240 }
241 
242 static int lm363x_regulator_probe(struct platform_device *pdev)
243 {
244 	struct ti_lmu *lmu = dev_get_drvdata(pdev->dev.parent);
245 	struct regmap *regmap = lmu->regmap;
246 	struct regulator_config cfg = { };
247 	struct regulator_dev *rdev;
248 	struct device *dev = &pdev->dev;
249 	int id = pdev->id;
250 	struct gpio_desc *gpiod;
251 	int ret;
252 
253 	cfg.dev = dev;
254 	cfg.regmap = regmap;
255 
256 	/*
257 	 * LM3632 LDOs can be controlled by external pin.
258 	 * Register update is required if the pin is used.
259 	 */
260 	gpiod = lm363x_regulator_of_get_enable_gpio(dev, id);
261 	if (IS_ERR(gpiod))
262 		return PTR_ERR(gpiod);
263 
264 	if (gpiod) {
265 		cfg.ena_gpiod = gpiod;
266 
267 		ret = regmap_update_bits(regmap, LM3632_REG_BIAS_CONFIG,
268 					 LM3632_EXT_EN_MASK,
269 					 LM3632_EXT_EN_MASK);
270 		if (ret) {
271 			gpiod_put(gpiod);
272 			dev_err(dev, "External pin err: %d\n", ret);
273 			return ret;
274 		}
275 	}
276 
277 	rdev = devm_regulator_register(dev, &lm363x_regulator_desc[id], &cfg);
278 	if (IS_ERR(rdev)) {
279 		ret = PTR_ERR(rdev);
280 		dev_err(dev, "[%d] regulator register err: %d\n", id, ret);
281 		return ret;
282 	}
283 
284 	return 0;
285 }
286 
287 static struct platform_driver lm363x_regulator_driver = {
288 	.probe = lm363x_regulator_probe,
289 	.driver = {
290 		.name = "lm363x-regulator",
291 	},
292 };
293 
294 module_platform_driver(lm363x_regulator_driver);
295 
296 MODULE_DESCRIPTION("TI LM363X Regulator Driver");
297 MODULE_AUTHOR("Milo Kim");
298 MODULE_LICENSE("GPL v2");
299 MODULE_ALIAS("platform:lm363x-regulator");
300