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
27struct 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
35struct 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
45static 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
67static 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
85static 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
102static 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
116static 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
130static 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
137static 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
161static 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
175static 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
197static 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
215static 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
240static 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
254static 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
276static 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
302static const struct regmap_config mp886x_regmap_config = {
303	.reg_bits = 8,
304	.val_bits = 8,
305};
306
307static 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
361static 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};
372MODULE_DEVICE_TABLE(of, mp886x_dt_ids);
373
374static const struct i2c_device_id mp886x_id[] = {
375	{ "mp886x", },
376	{ },
377};
378MODULE_DEVICE_TABLE(i2c, mp886x_id);
379
380static 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};
388module_i2c_driver(mp886x_regulator_driver);
389
390MODULE_AUTHOR("Jisheng Zhang <jszhang@kernel.org>");
391MODULE_DESCRIPTION("MP886x regulator driver");
392MODULE_LICENSE("GPL v2");
393