xref: /linux/drivers/regulator/mp886x.c (revision ca853314e78b0a65c20b6a889a23c31f918d4aa2)
1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // MP8867/MP8869 regulator driver
4 //
5 // Copyright (C) 2020 Synaptics Incorporated
6 //
7 // Author: Jisheng Zhang <jszhang@kernel.org>
8 
9 #include <linux/gpio/consumer.h>
10 #include <linux/i2c.h>
11 #include <linux/module.h>
12 #include <linux/of_device.h>
13 #include <linux/regmap.h>
14 #include <linux/regulator/driver.h>
15 #include <linux/regulator/of_regulator.h>
16 
17 #define MP886X_VSEL		0x00
18 #define  MP886X_V_BOOT		(1 << 7)
19 #define MP886X_SYSCNTLREG1	0x01
20 #define  MP886X_MODE		(1 << 0)
21 #define  MP886X_SLEW_SHIFT	3
22 #define  MP886X_SLEW_MASK	(0x7 << MP886X_SLEW_SHIFT)
23 #define  MP886X_GO		(1 << 6)
24 #define  MP886X_EN		(1 << 7)
25 #define MP8869_SYSCNTLREG2	0x02
26 
27 struct mp886x_cfg_info {
28 	const struct regulator_ops *rops;
29 	const int slew_rates[8];
30 	const int switch_freq[4];
31 	const u8 fs_reg;
32 	const u8 fs_shift;
33 };
34 
35 struct mp886x_device_info {
36 	struct device *dev;
37 	struct regulator_desc desc;
38 	struct regulator_init_data *regulator;
39 	struct gpio_desc *en_gpio;
40 	const struct mp886x_cfg_info *ci;
41 	u32 r[2];
42 	unsigned int sel;
43 };
44 
45 static int mp886x_set_ramp(struct regulator_dev *rdev, int ramp)
46 {
47 	struct mp886x_device_info *di = rdev_get_drvdata(rdev);
48 	const struct mp886x_cfg_info *ci = di->ci;
49 	int reg = -1, i;
50 
51 	for (i = 0; i < ARRAY_SIZE(ci->slew_rates); i++) {
52 		if (ramp <= ci->slew_rates[i])
53 			reg = i;
54 		else
55 			break;
56 	}
57 
58 	if (reg < 0) {
59 		dev_err(di->dev, "unsupported ramp value %d\n", ramp);
60 		return -EINVAL;
61 	}
62 
63 	return regmap_update_bits(rdev->regmap, MP886X_SYSCNTLREG1,
64 				  MP886X_SLEW_MASK, reg << MP886X_SLEW_SHIFT);
65 }
66 
67 static void mp886x_set_switch_freq(struct mp886x_device_info *di,
68 				   struct regmap *regmap,
69 				   u32 freq)
70 {
71 	const struct mp886x_cfg_info *ci = di->ci;
72 	int i;
73 
74 	for (i = 0; i < ARRAY_SIZE(ci->switch_freq); i++) {
75 		if (freq == ci->switch_freq[i]) {
76 			regmap_update_bits(regmap, ci->fs_reg,
77 				  0x3 << ci->fs_shift, i << ci->fs_shift);
78 			return;
79 		}
80 	}
81 
82 	dev_err(di->dev, "invalid frequency %d\n", freq);
83 }
84 
85 static int mp886x_set_mode(struct regulator_dev *rdev, unsigned int mode)
86 {
87 	switch (mode) {
88 	case REGULATOR_MODE_FAST:
89 		regmap_update_bits(rdev->regmap, MP886X_SYSCNTLREG1,
90 				   MP886X_MODE, MP886X_MODE);
91 		break;
92 	case REGULATOR_MODE_NORMAL:
93 		regmap_update_bits(rdev->regmap, MP886X_SYSCNTLREG1,
94 				   MP886X_MODE, 0);
95 		break;
96 	default:
97 		return -EINVAL;
98 	}
99 	return 0;
100 }
101 
102 static unsigned int mp886x_get_mode(struct regulator_dev *rdev)
103 {
104 	u32 val;
105 	int ret;
106 
107 	ret = regmap_read(rdev->regmap, MP886X_SYSCNTLREG1, &val);
108 	if (ret < 0)
109 		return ret;
110 	if (val & MP886X_MODE)
111 		return REGULATOR_MODE_FAST;
112 	else
113 		return REGULATOR_MODE_NORMAL;
114 }
115 
116 static int mp8869_set_voltage_sel(struct regulator_dev *rdev, unsigned int sel)
117 {
118 	int ret;
119 
120 	ret = regmap_update_bits(rdev->regmap, MP886X_SYSCNTLREG1,
121 				 MP886X_GO, MP886X_GO);
122 	if (ret < 0)
123 		return ret;
124 
125 	sel <<= ffs(rdev->desc->vsel_mask) - 1;
126 	return regmap_update_bits(rdev->regmap, rdev->desc->vsel_reg,
127 				  MP886X_V_BOOT | rdev->desc->vsel_mask, sel);
128 }
129 
130 static inline unsigned int mp8869_scale(unsigned int uv, u32 r1, u32 r2)
131 {
132 	u32 tmp = uv * r1 / r2;
133 
134 	return uv + tmp;
135 }
136 
137 static int mp8869_get_voltage_sel(struct regulator_dev *rdev)
138 {
139 	struct mp886x_device_info *di = rdev_get_drvdata(rdev);
140 	int ret, uv;
141 	unsigned int val;
142 	bool fbloop;
143 
144 	ret = regmap_read(rdev->regmap, rdev->desc->vsel_reg, &val);
145 	if (ret)
146 		return ret;
147 
148 	fbloop = val & MP886X_V_BOOT;
149 	if (fbloop) {
150 		uv = rdev->desc->min_uV;
151 		uv = mp8869_scale(uv, di->r[0], di->r[1]);
152 		return regulator_map_voltage_linear(rdev, uv, uv);
153 	}
154 
155 	val &= rdev->desc->vsel_mask;
156 	val >>= ffs(rdev->desc->vsel_mask) - 1;
157 
158 	return val;
159 }
160 
161 static const struct regulator_ops mp8869_regulator_ops = {
162 	.set_voltage_sel = mp8869_set_voltage_sel,
163 	.get_voltage_sel = mp8869_get_voltage_sel,
164 	.set_voltage_time_sel = regulator_set_voltage_time_sel,
165 	.map_voltage = regulator_map_voltage_linear,
166 	.list_voltage = regulator_list_voltage_linear,
167 	.enable = regulator_enable_regmap,
168 	.disable = regulator_disable_regmap,
169 	.is_enabled = regulator_is_enabled_regmap,
170 	.set_mode = mp886x_set_mode,
171 	.get_mode = mp886x_get_mode,
172 	.set_ramp_delay = mp886x_set_ramp,
173 };
174 
175 static const struct mp886x_cfg_info mp8869_ci = {
176 	.rops = &mp8869_regulator_ops,
177 	.slew_rates = {
178 		40000,
179 		30000,
180 		20000,
181 		10000,
182 		5000,
183 		2500,
184 		1250,
185 		625,
186 	},
187 	.switch_freq = {
188 		500000,
189 		750000,
190 		1000000,
191 		1250000,
192 	},
193 	.fs_reg = MP8869_SYSCNTLREG2,
194 	.fs_shift = 4,
195 };
196 
197 static int mp8867_set_voltage_sel(struct regulator_dev *rdev, unsigned int sel)
198 {
199 	struct mp886x_device_info *di = rdev_get_drvdata(rdev);
200 	int ret, delta;
201 
202 	ret = mp8869_set_voltage_sel(rdev, sel);
203 	if (ret < 0)
204 		return ret;
205 
206 	delta = di->sel - sel;
207 	if (abs(delta) <= 5)
208 		ret = regmap_update_bits(rdev->regmap, MP886X_SYSCNTLREG1,
209 					 MP886X_GO, 0);
210 	di->sel = sel;
211 
212 	return ret;
213 }
214 
215 static int mp8867_get_voltage_sel(struct regulator_dev *rdev)
216 {
217 	struct mp886x_device_info *di = rdev_get_drvdata(rdev);
218 	int ret, uv;
219 	unsigned int val;
220 	bool fbloop;
221 
222 	ret = regmap_read(rdev->regmap, rdev->desc->vsel_reg, &val);
223 	if (ret)
224 		return ret;
225 
226 	fbloop = val & MP886X_V_BOOT;
227 
228 	val &= rdev->desc->vsel_mask;
229 	val >>= ffs(rdev->desc->vsel_mask) - 1;
230 
231 	if (fbloop) {
232 		uv = regulator_list_voltage_linear(rdev, val);
233 		uv = mp8869_scale(uv, di->r[0], di->r[1]);
234 		return regulator_map_voltage_linear(rdev, uv, uv);
235 	}
236 
237 	return val;
238 }
239 
240 static const struct regulator_ops mp8867_regulator_ops = {
241 	.set_voltage_sel = mp8867_set_voltage_sel,
242 	.get_voltage_sel = mp8867_get_voltage_sel,
243 	.set_voltage_time_sel = regulator_set_voltage_time_sel,
244 	.map_voltage = regulator_map_voltage_linear,
245 	.list_voltage = regulator_list_voltage_linear,
246 	.enable = regulator_enable_regmap,
247 	.disable = regulator_disable_regmap,
248 	.is_enabled = regulator_is_enabled_regmap,
249 	.set_mode = mp886x_set_mode,
250 	.get_mode = mp886x_get_mode,
251 	.set_ramp_delay = mp886x_set_ramp,
252 };
253 
254 static const struct mp886x_cfg_info mp8867_ci = {
255 	.rops = &mp8867_regulator_ops,
256 	.slew_rates = {
257 		64000,
258 		32000,
259 		16000,
260 		8000,
261 		4000,
262 		2000,
263 		1000,
264 		500,
265 	},
266 	.switch_freq = {
267 		500000,
268 		750000,
269 		1000000,
270 		1500000,
271 	},
272 	.fs_reg = MP886X_SYSCNTLREG1,
273 	.fs_shift = 1,
274 };
275 
276 static int mp886x_regulator_register(struct mp886x_device_info *di,
277 				     struct regulator_config *config)
278 {
279 	struct regulator_desc *rdesc = &di->desc;
280 	struct regulator_dev *rdev;
281 
282 	rdesc->name = "mp886x-reg";
283 	rdesc->supply_name = "vin";
284 	rdesc->ops = di->ci->rops;
285 	rdesc->type = REGULATOR_VOLTAGE;
286 	rdesc->n_voltages = 128;
287 	rdesc->enable_reg = MP886X_SYSCNTLREG1;
288 	rdesc->enable_mask = MP886X_EN;
289 	rdesc->min_uV = 600000;
290 	rdesc->uV_step = 10000;
291 	rdesc->vsel_reg = MP886X_VSEL;
292 	rdesc->vsel_mask = 0x3f;
293 	rdesc->owner = THIS_MODULE;
294 
295 	rdev = devm_regulator_register(di->dev, &di->desc, config);
296 	if (IS_ERR(rdev))
297 		return PTR_ERR(rdev);
298 	di->sel = rdesc->ops->get_voltage_sel(rdev);
299 	return 0;
300 }
301 
302 static const struct regmap_config mp886x_regmap_config = {
303 	.reg_bits = 8,
304 	.val_bits = 8,
305 };
306 
307 static int mp886x_i2c_probe(struct i2c_client *client)
308 {
309 	struct device *dev = &client->dev;
310 	struct device_node *np = dev->of_node;
311 	struct mp886x_device_info *di;
312 	struct regulator_config config = { };
313 	struct regmap *regmap;
314 	u32 freq;
315 	int ret;
316 
317 	di = devm_kzalloc(dev, sizeof(struct mp886x_device_info), GFP_KERNEL);
318 	if (!di)
319 		return -ENOMEM;
320 
321 	di->regulator = of_get_regulator_init_data(dev, np, &di->desc);
322 	if (!di->regulator) {
323 		dev_err(dev, "Platform data not found!\n");
324 		return -EINVAL;
325 	}
326 
327 	ret = of_property_read_u32_array(np, "mps,fb-voltage-divider",
328 					 di->r, 2);
329 	if (ret)
330 		return ret;
331 
332 	di->en_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_HIGH);
333 	if (IS_ERR(di->en_gpio))
334 		return PTR_ERR(di->en_gpio);
335 
336 	di->ci = of_device_get_match_data(dev);
337 	di->dev = dev;
338 
339 	regmap = devm_regmap_init_i2c(client, &mp886x_regmap_config);
340 	if (IS_ERR(regmap)) {
341 		dev_err(dev, "Failed to allocate regmap!\n");
342 		return PTR_ERR(regmap);
343 	}
344 	i2c_set_clientdata(client, di);
345 
346 	config.dev = di->dev;
347 	config.init_data = di->regulator;
348 	config.regmap = regmap;
349 	config.driver_data = di;
350 	config.of_node = np;
351 
352 	if (!of_property_read_u32(np, "mps,switch-frequency-hz", &freq))
353 		mp886x_set_switch_freq(di, regmap, freq);
354 
355 	ret = mp886x_regulator_register(di, &config);
356 	if (ret < 0)
357 		dev_err(dev, "Failed to register regulator!\n");
358 	return ret;
359 }
360 
361 static const struct of_device_id mp886x_dt_ids[] = {
362 	{
363 		.compatible = "mps,mp8867",
364 		.data = &mp8867_ci
365 	},
366 	{
367 		.compatible = "mps,mp8869",
368 		.data = &mp8869_ci
369 	},
370 	{ }
371 };
372 MODULE_DEVICE_TABLE(of, mp886x_dt_ids);
373 
374 static const struct i2c_device_id mp886x_id[] = {
375 	{ "mp886x", },
376 	{ },
377 };
378 MODULE_DEVICE_TABLE(i2c, mp886x_id);
379 
380 static struct i2c_driver mp886x_regulator_driver = {
381 	.driver = {
382 		.name = "mp886x-regulator",
383 		.of_match_table = of_match_ptr(mp886x_dt_ids),
384 	},
385 	.probe_new = mp886x_i2c_probe,
386 	.id_table = mp886x_id,
387 };
388 module_i2c_driver(mp886x_regulator_driver);
389 
390 MODULE_AUTHOR("Jisheng Zhang <jszhang@kernel.org>");
391 MODULE_DESCRIPTION("MP886x regulator driver");
392 MODULE_LICENSE("GPL v2");
393