1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // mpq7920.c  - regulator driver for mps mpq7920
4 //
5 // Copyright 2019 Monolithic Power Systems, Inc
6 //
7 // Author: Saravanan Sekar <sravanhome@gmail.com>
8 
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/err.h>
13 #include <linux/of.h>
14 #include <linux/platform_device.h>
15 #include <linux/regulator/driver.h>
16 #include <linux/regulator/of_regulator.h>
17 #include <linux/i2c.h>
18 #include <linux/regmap.h>
19 #include "mpq7920.h"
20 
21 #define MPQ7920_BUCK_VOLT_RANGE \
22 	((MPQ7920_VOLT_MAX - MPQ7920_BUCK_VOLT_MIN)/MPQ7920_VOLT_STEP + 1)
23 #define MPQ7920_LDO_VOLT_RANGE \
24 	((MPQ7920_VOLT_MAX - MPQ7920_LDO_VOLT_MIN)/MPQ7920_VOLT_STEP + 1)
25 
26 #define MPQ7920BUCK(_name, _id, _ilim)					\
27 	[MPQ7920_BUCK ## _id] = {					\
28 		.id = MPQ7920_BUCK ## _id,				\
29 		.name = _name,						\
30 		.of_match = _name,					\
31 		.regulators_node = "regulators",			\
32 		.of_parse_cb = mpq7920_parse_cb,			\
33 		.ops = &mpq7920_buck_ops,				\
34 		.min_uV = MPQ7920_BUCK_VOLT_MIN,			\
35 		.uV_step = MPQ7920_VOLT_STEP,				\
36 		.n_voltages = MPQ7920_BUCK_VOLT_RANGE,			\
37 		.curr_table = _ilim,					\
38 		.n_current_limits = ARRAY_SIZE(_ilim),			\
39 		.csel_reg = MPQ7920_BUCK ##_id## _REG_C,		\
40 		.csel_mask = MPQ7920_MASK_BUCK_ILIM,			\
41 		.enable_reg = MPQ7920_REG_REGULATOR_EN,			\
42 		.enable_mask = BIT(MPQ7920_REGULATOR_EN_OFFSET -	\
43 					 MPQ7920_BUCK ## _id),		\
44 		.vsel_reg = MPQ7920_BUCK ##_id## _REG_A,		\
45 		.vsel_mask = MPQ7920_MASK_VREF,				\
46 		.active_discharge_on	= MPQ7920_DISCHARGE_ON,		\
47 		.active_discharge_reg	= MPQ7920_BUCK ##_id## _REG_B,	\
48 		.active_discharge_mask	= MPQ7920_MASK_DISCHARGE,	\
49 		.soft_start_reg		= MPQ7920_BUCK ##_id## _REG_C,	\
50 		.soft_start_mask	= MPQ7920_MASK_SOFTSTART,	\
51 		.owner			= THIS_MODULE,			\
52 	}
53 
54 #define MPQ7920LDO(_name, _id, _ops, _ilim, _ilim_sz, _creg, _cmask)	\
55 	[MPQ7920_LDO ## _id] = {					\
56 		.id = MPQ7920_LDO ## _id,				\
57 		.name = _name,						\
58 		.of_match = _name,					\
59 		.regulators_node = "regulators",			\
60 		.ops = _ops,						\
61 		.min_uV = MPQ7920_LDO_VOLT_MIN,				\
62 		.uV_step = MPQ7920_VOLT_STEP,				\
63 		.n_voltages = MPQ7920_LDO_VOLT_RANGE,			\
64 		.vsel_reg = MPQ7920_LDO ##_id## _REG_A,			\
65 		.vsel_mask = MPQ7920_MASK_VREF,				\
66 		.curr_table = _ilim,					\
67 		.n_current_limits = _ilim_sz,				\
68 		.csel_reg = _creg,					\
69 		.csel_mask = _cmask,					\
70 		.enable_reg = (_id == 1) ? 0 : MPQ7920_REG_REGULATOR_EN,\
71 		.enable_mask = BIT(MPQ7920_REGULATOR_EN_OFFSET -	\
72 					MPQ7920_LDO ##_id + 1),		\
73 		.active_discharge_on	= MPQ7920_DISCHARGE_ON,		\
74 		.active_discharge_mask	= MPQ7920_MASK_DISCHARGE,	\
75 		.active_discharge_reg	= MPQ7920_LDO ##_id## _REG_B,	\
76 		.type			= REGULATOR_VOLTAGE,		\
77 		.owner			= THIS_MODULE,			\
78 	}
79 
80 enum mpq7920_regulators {
81 	MPQ7920_BUCK1,
82 	MPQ7920_BUCK2,
83 	MPQ7920_BUCK3,
84 	MPQ7920_BUCK4,
85 	MPQ7920_LDO1, /* LDORTC */
86 	MPQ7920_LDO2,
87 	MPQ7920_LDO3,
88 	MPQ7920_LDO4,
89 	MPQ7920_LDO5,
90 	MPQ7920_MAX_REGULATORS,
91 };
92 
93 struct mpq7920_regulator_info {
94 	struct regmap *regmap;
95 	struct regulator_desc *rdesc;
96 };
97 
98 static const struct regmap_config mpq7920_regmap_config = {
99 	.reg_bits = 8,
100 	.val_bits = 8,
101 	.max_register = 0x25,
102 };
103 
104 /* Current limits array (in uA)
105  * ILIM1 & ILIM3
106  */
107 static const unsigned int mpq7920_I_limits1[] = {
108 	4600000, 6600000, 7600000, 9300000
109 };
110 
111 /* ILIM2 & ILIM4 */
112 static const unsigned int mpq7920_I_limits2[] = {
113 	2700000, 3900000, 5100000, 6100000
114 };
115 
116 /* LDO4 & LDO5 */
117 static const unsigned int mpq7920_I_limits3[] = {
118 	300000, 700000
119 };
120 
121 static int mpq7920_set_ramp_delay(struct regulator_dev *rdev, int ramp_delay);
122 static int mpq7920_parse_cb(struct device_node *np,
123 				const struct regulator_desc *rdesc,
124 				struct regulator_config *config);
125 
126 /* RTCLDO not controllable, always ON */
127 static const struct regulator_ops mpq7920_ldortc_ops = {
128 	.list_voltage		= regulator_list_voltage_linear,
129 	.map_voltage		= regulator_map_voltage_linear,
130 	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
131 	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
132 };
133 
134 static const struct regulator_ops mpq7920_ldo_wo_current_ops = {
135 	.enable			= regulator_enable_regmap,
136 	.disable		= regulator_disable_regmap,
137 	.is_enabled		= regulator_is_enabled_regmap,
138 	.list_voltage		= regulator_list_voltage_linear,
139 	.map_voltage		= regulator_map_voltage_linear,
140 	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
141 	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
142 	.set_active_discharge	= regulator_set_active_discharge_regmap,
143 };
144 
145 static const struct regulator_ops mpq7920_ldo_ops = {
146 	.enable			= regulator_enable_regmap,
147 	.disable		= regulator_disable_regmap,
148 	.is_enabled		= regulator_is_enabled_regmap,
149 	.list_voltage		= regulator_list_voltage_linear,
150 	.map_voltage		= regulator_map_voltage_linear,
151 	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
152 	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
153 	.set_active_discharge	= regulator_set_active_discharge_regmap,
154 	.get_current_limit	= regulator_get_current_limit_regmap,
155 	.set_current_limit	= regulator_set_current_limit_regmap,
156 };
157 
158 static const struct regulator_ops mpq7920_buck_ops = {
159 	.enable			= regulator_enable_regmap,
160 	.disable		= regulator_disable_regmap,
161 	.is_enabled		= regulator_is_enabled_regmap,
162 	.list_voltage		= regulator_list_voltage_linear,
163 	.map_voltage		= regulator_map_voltage_linear,
164 	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
165 	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
166 	.set_active_discharge	= regulator_set_active_discharge_regmap,
167 	.set_soft_start		= regulator_set_soft_start_regmap,
168 	.set_ramp_delay		= mpq7920_set_ramp_delay,
169 };
170 
171 static struct regulator_desc mpq7920_regulators_desc[MPQ7920_MAX_REGULATORS] = {
172 	MPQ7920BUCK("buck1", 1, mpq7920_I_limits1),
173 	MPQ7920BUCK("buck2", 2, mpq7920_I_limits2),
174 	MPQ7920BUCK("buck3", 3, mpq7920_I_limits1),
175 	MPQ7920BUCK("buck4", 4, mpq7920_I_limits2),
176 	MPQ7920LDO("ldortc", 1, &mpq7920_ldortc_ops, NULL, 0, 0, 0),
177 	MPQ7920LDO("ldo2", 2, &mpq7920_ldo_wo_current_ops, NULL, 0, 0, 0),
178 	MPQ7920LDO("ldo3", 3, &mpq7920_ldo_wo_current_ops, NULL, 0, 0, 0),
179 	MPQ7920LDO("ldo4", 4, &mpq7920_ldo_ops, mpq7920_I_limits3,
180 			ARRAY_SIZE(mpq7920_I_limits3), MPQ7920_LDO4_REG_B,
181 			MPQ7920_MASK_LDO_ILIM),
182 	MPQ7920LDO("ldo5", 5, &mpq7920_ldo_ops, mpq7920_I_limits3,
183 			ARRAY_SIZE(mpq7920_I_limits3), MPQ7920_LDO5_REG_B,
184 			MPQ7920_MASK_LDO_ILIM),
185 };
186 
187 /*
188  * DVS ramp rate BUCK1 to BUCK4
189  * 00-01: Reserved
190  * 10: 8mV/us
191  * 11: 4mV/us
192  */
mpq7920_set_ramp_delay(struct regulator_dev * rdev,int ramp_delay)193 static int mpq7920_set_ramp_delay(struct regulator_dev *rdev, int ramp_delay)
194 {
195 	unsigned int ramp_val;
196 
197 	if (ramp_delay > 8000 || ramp_delay < 0)
198 		return -EINVAL;
199 
200 	if (ramp_delay <= 4000)
201 		ramp_val = 3;
202 	else
203 		ramp_val = 2;
204 
205 	return regmap_update_bits(rdev->regmap, MPQ7920_REG_CTL0,
206 				  MPQ7920_MASK_DVS_SLEWRATE, ramp_val << 6);
207 }
208 
mpq7920_parse_cb(struct device_node * np,const struct regulator_desc * desc,struct regulator_config * config)209 static int mpq7920_parse_cb(struct device_node *np,
210 				const struct regulator_desc *desc,
211 				struct regulator_config *config)
212 {
213 	uint8_t val;
214 	int ret;
215 	struct mpq7920_regulator_info *info = config->driver_data;
216 	struct regulator_desc *rdesc = &info->rdesc[desc->id];
217 
218 	if (of_property_read_bool(np, "mps,buck-ovp-disable")) {
219 		regmap_update_bits(config->regmap,
220 				MPQ7920_BUCK1_REG_B + (rdesc->id * 4),
221 				MPQ7920_MASK_OVP, MPQ7920_OVP_DISABLE);
222 	}
223 
224 	ret = of_property_read_u8(np, "mps,buck-phase-delay", &val);
225 	if (!ret) {
226 		regmap_update_bits(config->regmap,
227 				MPQ7920_BUCK1_REG_C + (rdesc->id * 4),
228 				MPQ7920_MASK_BUCK_PHASE_DEALY,
229 				(val & 3) << 4);
230 	}
231 
232 	ret = of_property_read_u8(np, "mps,buck-softstart", &val);
233 	if (!ret)
234 		rdesc->soft_start_val_on = (val & 3) << 2;
235 
236 	return 0;
237 }
238 
mpq7920_parse_dt(struct device * dev,struct mpq7920_regulator_info * info)239 static void mpq7920_parse_dt(struct device *dev,
240 		 struct mpq7920_regulator_info *info)
241 {
242 	int ret;
243 	struct device_node *np = dev->of_node;
244 	uint8_t freq;
245 
246 	np = of_get_child_by_name(np, "regulators");
247 	if (!np) {
248 		dev_err(dev, "missing 'regulators' subnode in DT\n");
249 		return;
250 	}
251 
252 	ret = of_property_read_u8(np, "mps,switch-freq", &freq);
253 	if (!ret) {
254 		regmap_update_bits(info->regmap, MPQ7920_REG_CTL0,
255 					MPQ7920_MASK_SWITCH_FREQ,
256 					(freq & 3) << 4);
257 	}
258 
259 	of_node_put(np);
260 }
261 
mpq7920_i2c_probe(struct i2c_client * client)262 static int mpq7920_i2c_probe(struct i2c_client *client)
263 {
264 	struct device *dev = &client->dev;
265 	struct mpq7920_regulator_info *info;
266 	struct regulator_config config = { NULL, };
267 	struct regulator_dev *rdev;
268 	struct regmap *regmap;
269 	int i;
270 
271 	info = devm_kzalloc(dev, sizeof(struct mpq7920_regulator_info),
272 				GFP_KERNEL);
273 	if (!info)
274 		return -ENOMEM;
275 
276 	info->rdesc = mpq7920_regulators_desc;
277 	regmap = devm_regmap_init_i2c(client, &mpq7920_regmap_config);
278 	if (IS_ERR(regmap)) {
279 		dev_err(dev, "Failed to allocate regmap!\n");
280 		return PTR_ERR(regmap);
281 	}
282 
283 	i2c_set_clientdata(client, info);
284 	info->regmap = regmap;
285 	if (client->dev.of_node)
286 		mpq7920_parse_dt(&client->dev, info);
287 
288 	config.dev = dev;
289 	config.regmap = regmap;
290 	config.driver_data = info;
291 
292 	for (i = 0; i < MPQ7920_MAX_REGULATORS; i++) {
293 		rdev = devm_regulator_register(dev,
294 					       &mpq7920_regulators_desc[i],
295 					       &config);
296 		if (IS_ERR(rdev)) {
297 			dev_err(dev, "Failed to register regulator!\n");
298 			return PTR_ERR(rdev);
299 		}
300 	}
301 
302 	return 0;
303 }
304 
305 static const struct of_device_id mpq7920_of_match[] = {
306 	{ .compatible = "mps,mpq7920"},
307 	{},
308 };
309 MODULE_DEVICE_TABLE(of, mpq7920_of_match);
310 
311 static const struct i2c_device_id mpq7920_id[] = {
312 	{ "mpq7920", },
313 	{ },
314 };
315 MODULE_DEVICE_TABLE(i2c, mpq7920_id);
316 
317 static struct i2c_driver mpq7920_regulator_driver = {
318 	.driver = {
319 		.name = "mpq7920",
320 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
321 		.of_match_table = mpq7920_of_match,
322 	},
323 	.probe = mpq7920_i2c_probe,
324 	.id_table = mpq7920_id,
325 };
326 module_i2c_driver(mpq7920_regulator_driver);
327 
328 MODULE_AUTHOR("Saravanan Sekar <sravanhome@gmail.com>");
329 MODULE_DESCRIPTION("MPQ7920 PMIC regulator driver");
330 MODULE_LICENSE("GPL");
331