1 // SPDX-License-Identifier: GPL-2.0+
2 
3 #include <linux/bitops.h>
4 #include <linux/delay.h>
5 #include <linux/gpio/consumer.h>
6 #include <linux/i2c.h>
7 #include <linux/kernel.h>
8 #include <linux/module.h>
9 #include <linux/mutex.h>
10 #include <linux/regmap.h>
11 #include <linux/regulator/driver.h>
12 
13 enum {
14 	RTQ6752_IDX_PAVDD = 0,
15 	RTQ6752_IDX_NAVDD = 1,
16 	RTQ6752_IDX_MAX
17 };
18 
19 #define RTQ6752_REG_PAVDD	0x00
20 #define RTQ6752_REG_NAVDD	0x01
21 #define RTQ6752_REG_PAVDDONDLY	0x07
22 #define RTQ6752_REG_PAVDDSSTIME	0x08
23 #define RTQ6752_REG_NAVDDONDLY	0x0D
24 #define RTQ6752_REG_NAVDDSSTIME	0x0E
25 #define RTQ6752_REG_OPTION1	0x12
26 #define RTQ6752_REG_CHSWITCH	0x16
27 #define RTQ6752_REG_FAULT	0x1D
28 
29 #define RTQ6752_VOUT_MASK	GENMASK(5, 0)
30 #define RTQ6752_NAVDDEN_MASK	BIT(3)
31 #define RTQ6752_PAVDDEN_MASK	BIT(0)
32 #define RTQ6752_PAVDDAD_MASK	BIT(4)
33 #define RTQ6752_NAVDDAD_MASK	BIT(3)
34 #define RTQ6752_PAVDDF_MASK	BIT(3)
35 #define RTQ6752_NAVDDF_MASK	BIT(0)
36 #define RTQ6752_ENABLE_MASK	(BIT(RTQ6752_IDX_MAX) - 1)
37 
38 #define RTQ6752_VOUT_MINUV	5000000
39 #define RTQ6752_VOUT_STEPUV	50000
40 #define RTQ6752_VOUT_NUM	47
41 #define RTQ6752_I2CRDY_TIMEUS	1000
42 #define RTQ6752_MINSS_TIMEUS	5000
43 
44 struct rtq6752_priv {
45 	struct regmap *regmap;
46 	struct gpio_desc *enable_gpio;
47 	struct mutex lock;
48 	unsigned char enable_flag;
49 };
50 
51 static int rtq6752_set_vdd_enable(struct regulator_dev *rdev)
52 {
53 	struct rtq6752_priv *priv = rdev_get_drvdata(rdev);
54 	int rid = rdev_get_id(rdev), ret;
55 
56 	mutex_lock(&priv->lock);
57 	if (!priv->enable_flag) {
58 		if (priv->enable_gpio) {
59 			gpiod_set_value(priv->enable_gpio, 1);
60 
61 			usleep_range(RTQ6752_I2CRDY_TIMEUS,
62 				     RTQ6752_I2CRDY_TIMEUS + 100);
63 		}
64 
65 		regcache_cache_only(priv->regmap, false);
66 		ret = regcache_sync(priv->regmap);
67 		if (ret) {
68 			mutex_unlock(&priv->lock);
69 			return ret;
70 		}
71 	}
72 
73 	priv->enable_flag |= BIT(rid);
74 	mutex_unlock(&priv->lock);
75 
76 	return regulator_enable_regmap(rdev);
77 }
78 
79 static int rtq6752_set_vdd_disable(struct regulator_dev *rdev)
80 {
81 	struct rtq6752_priv *priv = rdev_get_drvdata(rdev);
82 	int rid = rdev_get_id(rdev), ret;
83 
84 	ret = regulator_disable_regmap(rdev);
85 	if (ret)
86 		return ret;
87 
88 	mutex_lock(&priv->lock);
89 	priv->enable_flag &= ~BIT(rid);
90 
91 	if (!priv->enable_flag) {
92 		regcache_cache_only(priv->regmap, true);
93 		regcache_mark_dirty(priv->regmap);
94 
95 		if (priv->enable_gpio)
96 			gpiod_set_value(priv->enable_gpio, 0);
97 
98 	}
99 	mutex_unlock(&priv->lock);
100 
101 	return 0;
102 }
103 
104 static int rtq6752_get_error_flags(struct regulator_dev *rdev,
105 				   unsigned int *flags)
106 {
107 	unsigned int val, events = 0;
108 	const unsigned int fault_mask[] = {
109 		RTQ6752_PAVDDF_MASK, RTQ6752_NAVDDF_MASK };
110 	int rid = rdev_get_id(rdev), ret;
111 
112 	ret = regmap_read(rdev->regmap, RTQ6752_REG_FAULT, &val);
113 	if (ret)
114 		return ret;
115 
116 	if (val & fault_mask[rid])
117 		events = REGULATOR_ERROR_REGULATION_OUT;
118 
119 	*flags = events;
120 	return 0;
121 }
122 
123 static const struct regulator_ops rtq6752_regulator_ops = {
124 	.list_voltage = regulator_list_voltage_linear,
125 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
126 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
127 	.enable = rtq6752_set_vdd_enable,
128 	.disable = rtq6752_set_vdd_disable,
129 	.is_enabled = regulator_is_enabled_regmap,
130 	.set_active_discharge = regulator_set_active_discharge_regmap,
131 	.get_error_flags = rtq6752_get_error_flags,
132 };
133 
134 static const struct regulator_desc rtq6752_regulator_descs[] = {
135 	{
136 		.name = "rtq6752-pavdd",
137 		.of_match = of_match_ptr("pavdd"),
138 		.regulators_node = of_match_ptr("regulators"),
139 		.id = RTQ6752_IDX_PAVDD,
140 		.n_voltages = RTQ6752_VOUT_NUM,
141 		.ops = &rtq6752_regulator_ops,
142 		.owner = THIS_MODULE,
143 		.min_uV = RTQ6752_VOUT_MINUV,
144 		.uV_step = RTQ6752_VOUT_STEPUV,
145 		.enable_time = RTQ6752_MINSS_TIMEUS,
146 		.vsel_reg = RTQ6752_REG_PAVDD,
147 		.vsel_mask = RTQ6752_VOUT_MASK,
148 		.enable_reg = RTQ6752_REG_CHSWITCH,
149 		.enable_mask = RTQ6752_PAVDDEN_MASK,
150 		.active_discharge_reg = RTQ6752_REG_OPTION1,
151 		.active_discharge_mask = RTQ6752_PAVDDAD_MASK,
152 		.active_discharge_off = RTQ6752_PAVDDAD_MASK,
153 	},
154 	{
155 		.name = "rtq6752-navdd",
156 		.of_match = of_match_ptr("navdd"),
157 		.regulators_node = of_match_ptr("regulators"),
158 		.id = RTQ6752_IDX_NAVDD,
159 		.n_voltages = RTQ6752_VOUT_NUM,
160 		.ops = &rtq6752_regulator_ops,
161 		.owner = THIS_MODULE,
162 		.min_uV = RTQ6752_VOUT_MINUV,
163 		.uV_step = RTQ6752_VOUT_STEPUV,
164 		.enable_time = RTQ6752_MINSS_TIMEUS,
165 		.vsel_reg = RTQ6752_REG_NAVDD,
166 		.vsel_mask = RTQ6752_VOUT_MASK,
167 		.enable_reg = RTQ6752_REG_CHSWITCH,
168 		.enable_mask = RTQ6752_NAVDDEN_MASK,
169 		.active_discharge_reg = RTQ6752_REG_OPTION1,
170 		.active_discharge_mask = RTQ6752_NAVDDAD_MASK,
171 		.active_discharge_off = RTQ6752_NAVDDAD_MASK,
172 	}
173 };
174 
175 static int rtq6752_init_device_properties(struct rtq6752_priv *priv)
176 {
177 	u8 raw_vals[] = { 0, 0 };
178 	int ret;
179 
180 	/* Configure PAVDD on and softstart delay time to the minimum */
181 	ret = regmap_raw_write(priv->regmap, RTQ6752_REG_PAVDDONDLY, raw_vals,
182 			       ARRAY_SIZE(raw_vals));
183 	if (ret)
184 		return ret;
185 
186 	/* Configure NAVDD on and softstart delay time to the minimum */
187 	return regmap_raw_write(priv->regmap, RTQ6752_REG_NAVDDONDLY, raw_vals,
188 				ARRAY_SIZE(raw_vals));
189 }
190 
191 static bool rtq6752_is_volatile_reg(struct device *dev, unsigned int reg)
192 {
193 	if (reg == RTQ6752_REG_FAULT)
194 		return true;
195 	return false;
196 }
197 
198 static const struct reg_default rtq6752_reg_defaults[] = {
199 	{ RTQ6752_REG_PAVDD, 0x14 },
200 	{ RTQ6752_REG_NAVDD, 0x14 },
201 	{ RTQ6752_REG_PAVDDONDLY, 0x01 },
202 	{ RTQ6752_REG_PAVDDSSTIME, 0x01 },
203 	{ RTQ6752_REG_NAVDDONDLY, 0x01 },
204 	{ RTQ6752_REG_NAVDDSSTIME, 0x01 },
205 	{ RTQ6752_REG_OPTION1, 0x07 },
206 	{ RTQ6752_REG_CHSWITCH, 0x29 },
207 };
208 
209 static const struct regmap_config rtq6752_regmap_config = {
210 	.reg_bits = 8,
211 	.val_bits = 8,
212 	.cache_type = REGCACHE_RBTREE,
213 	.max_register = RTQ6752_REG_FAULT,
214 	.reg_defaults = rtq6752_reg_defaults,
215 	.num_reg_defaults = ARRAY_SIZE(rtq6752_reg_defaults),
216 	.volatile_reg = rtq6752_is_volatile_reg,
217 };
218 
219 static int rtq6752_probe(struct i2c_client *i2c)
220 {
221 	struct rtq6752_priv *priv;
222 	struct regulator_config reg_cfg = {};
223 	struct regulator_dev *rdev;
224 	int i, ret;
225 
226 	priv = devm_kzalloc(&i2c->dev, sizeof(*priv), GFP_KERNEL);
227 	if (!priv)
228 		return -ENOMEM;
229 
230 	mutex_init(&priv->lock);
231 
232 	priv->enable_gpio = devm_gpiod_get_optional(&i2c->dev, "enable",
233 						    GPIOD_OUT_HIGH);
234 	if (IS_ERR(priv->enable_gpio)) {
235 		dev_err(&i2c->dev, "Failed to get 'enable' gpio\n");
236 		return PTR_ERR(priv->enable_gpio);
237 	}
238 
239 	usleep_range(RTQ6752_I2CRDY_TIMEUS, RTQ6752_I2CRDY_TIMEUS + 100);
240 	/* Default EN pin to high, PAVDD and NAVDD will be on */
241 	priv->enable_flag = RTQ6752_ENABLE_MASK;
242 
243 	priv->regmap = devm_regmap_init_i2c(i2c, &rtq6752_regmap_config);
244 	if (IS_ERR(priv->regmap)) {
245 		dev_err(&i2c->dev, "Failed to init regmap\n");
246 		return PTR_ERR(priv->regmap);
247 	}
248 
249 	ret = rtq6752_init_device_properties(priv);
250 	if (ret) {
251 		dev_err(&i2c->dev, "Failed to init device properties\n");
252 		return ret;
253 	}
254 
255 	reg_cfg.dev = &i2c->dev;
256 	reg_cfg.regmap = priv->regmap;
257 	reg_cfg.driver_data = priv;
258 
259 	for (i = 0; i < ARRAY_SIZE(rtq6752_regulator_descs); i++) {
260 		rdev = devm_regulator_register(&i2c->dev,
261 					       rtq6752_regulator_descs + i,
262 					       &reg_cfg);
263 		if (IS_ERR(rdev)) {
264 			dev_err(&i2c->dev, "Failed to init %d regulator\n", i);
265 			return PTR_ERR(rdev);
266 		}
267 	}
268 
269 	return 0;
270 }
271 
272 static const struct of_device_id __maybe_unused rtq6752_device_table[] = {
273 	{ .compatible = "richtek,rtq6752", },
274 	{}
275 };
276 MODULE_DEVICE_TABLE(of, rtq6752_device_table);
277 
278 static struct i2c_driver rtq6752_driver = {
279 	.driver = {
280 		.name = "rtq6752",
281 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
282 		.of_match_table = rtq6752_device_table,
283 	},
284 	.probe = rtq6752_probe,
285 };
286 module_i2c_driver(rtq6752_driver);
287 
288 MODULE_AUTHOR("ChiYuan Huang <cy_huang@richtek.com>");
289 MODULE_DESCRIPTION("Richtek RTQ6752 Regulator Driver");
290 MODULE_LICENSE("GPL v2");
291