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.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 unsigned 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 void mp886x_set_switch_freq(struct mp886x_device_info *di,
46				   struct regmap *regmap,
47				   u32 freq)
48{
49	const struct mp886x_cfg_info *ci = di->ci;
50	int i;
51
52	for (i = 0; i < ARRAY_SIZE(ci->switch_freq); i++) {
53		if (freq == ci->switch_freq[i]) {
54			regmap_update_bits(regmap, ci->fs_reg,
55				  0x3 << ci->fs_shift, i << ci->fs_shift);
56			return;
57		}
58	}
59
60	dev_err(di->dev, "invalid frequency %d\n", freq);
61}
62
63static int mp886x_set_mode(struct regulator_dev *rdev, unsigned int mode)
64{
65	switch (mode) {
66	case REGULATOR_MODE_FAST:
67		regmap_update_bits(rdev->regmap, MP886X_SYSCNTLREG1,
68				   MP886X_MODE, MP886X_MODE);
69		break;
70	case REGULATOR_MODE_NORMAL:
71		regmap_update_bits(rdev->regmap, MP886X_SYSCNTLREG1,
72				   MP886X_MODE, 0);
73		break;
74	default:
75		return -EINVAL;
76	}
77	return 0;
78}
79
80static unsigned int mp886x_get_mode(struct regulator_dev *rdev)
81{
82	u32 val;
83	int ret;
84
85	ret = regmap_read(rdev->regmap, MP886X_SYSCNTLREG1, &val);
86	if (ret < 0)
87		return ret;
88	if (val & MP886X_MODE)
89		return REGULATOR_MODE_FAST;
90	else
91		return REGULATOR_MODE_NORMAL;
92}
93
94static int mp8869_set_voltage_sel(struct regulator_dev *rdev, unsigned int sel)
95{
96	int ret;
97
98	ret = regmap_update_bits(rdev->regmap, MP886X_SYSCNTLREG1,
99				 MP886X_GO, MP886X_GO);
100	if (ret < 0)
101		return ret;
102
103	sel <<= ffs(rdev->desc->vsel_mask) - 1;
104	return regmap_update_bits(rdev->regmap, rdev->desc->vsel_reg,
105				  MP886X_V_BOOT | rdev->desc->vsel_mask, sel);
106}
107
108static inline unsigned int mp8869_scale(unsigned int uv, u32 r1, u32 r2)
109{
110	u32 tmp = uv * r1 / r2;
111
112	return uv + tmp;
113}
114
115static int mp8869_get_voltage_sel(struct regulator_dev *rdev)
116{
117	struct mp886x_device_info *di = rdev_get_drvdata(rdev);
118	int ret, uv;
119	unsigned int val;
120	bool fbloop;
121
122	ret = regmap_read(rdev->regmap, rdev->desc->vsel_reg, &val);
123	if (ret)
124		return ret;
125
126	fbloop = val & MP886X_V_BOOT;
127	if (fbloop) {
128		uv = rdev->desc->min_uV;
129		uv = mp8869_scale(uv, di->r[0], di->r[1]);
130		return regulator_map_voltage_linear(rdev, uv, uv);
131	}
132
133	val &= rdev->desc->vsel_mask;
134	val >>= ffs(rdev->desc->vsel_mask) - 1;
135
136	return val;
137}
138
139static const struct regulator_ops mp8869_regulator_ops = {
140	.set_voltage_sel = mp8869_set_voltage_sel,
141	.get_voltage_sel = mp8869_get_voltage_sel,
142	.set_voltage_time_sel = regulator_set_voltage_time_sel,
143	.map_voltage = regulator_map_voltage_linear,
144	.list_voltage = regulator_list_voltage_linear,
145	.enable = regulator_enable_regmap,
146	.disable = regulator_disable_regmap,
147	.is_enabled = regulator_is_enabled_regmap,
148	.set_mode = mp886x_set_mode,
149	.get_mode = mp886x_get_mode,
150	.set_ramp_delay = regulator_set_ramp_delay_regmap,
151};
152
153static const struct mp886x_cfg_info mp8869_ci = {
154	.rops = &mp8869_regulator_ops,
155	.slew_rates = {
156		40000,
157		30000,
158		20000,
159		10000,
160		5000,
161		2500,
162		1250,
163		625,
164	},
165	.switch_freq = {
166		500000,
167		750000,
168		1000000,
169		1250000,
170	},
171	.fs_reg = MP8869_SYSCNTLREG2,
172	.fs_shift = 4,
173};
174
175static int mp8867_set_voltage_sel(struct regulator_dev *rdev, unsigned int sel)
176{
177	struct mp886x_device_info *di = rdev_get_drvdata(rdev);
178	int ret, delta;
179
180	ret = mp8869_set_voltage_sel(rdev, sel);
181	if (ret < 0)
182		return ret;
183
184	delta = di->sel - sel;
185	if (abs(delta) <= 5)
186		ret = regmap_update_bits(rdev->regmap, MP886X_SYSCNTLREG1,
187					 MP886X_GO, 0);
188	di->sel = sel;
189
190	return ret;
191}
192
193static int mp8867_get_voltage_sel(struct regulator_dev *rdev)
194{
195	struct mp886x_device_info *di = rdev_get_drvdata(rdev);
196	int ret, uv;
197	unsigned int val;
198	bool fbloop;
199
200	ret = regmap_read(rdev->regmap, rdev->desc->vsel_reg, &val);
201	if (ret)
202		return ret;
203
204	fbloop = val & MP886X_V_BOOT;
205
206	val &= rdev->desc->vsel_mask;
207	val >>= ffs(rdev->desc->vsel_mask) - 1;
208
209	if (fbloop) {
210		uv = regulator_list_voltage_linear(rdev, val);
211		uv = mp8869_scale(uv, di->r[0], di->r[1]);
212		return regulator_map_voltage_linear(rdev, uv, uv);
213	}
214
215	return val;
216}
217
218static const struct regulator_ops mp8867_regulator_ops = {
219	.set_voltage_sel = mp8867_set_voltage_sel,
220	.get_voltage_sel = mp8867_get_voltage_sel,
221	.set_voltage_time_sel = regulator_set_voltage_time_sel,
222	.map_voltage = regulator_map_voltage_linear,
223	.list_voltage = regulator_list_voltage_linear,
224	.enable = regulator_enable_regmap,
225	.disable = regulator_disable_regmap,
226	.is_enabled = regulator_is_enabled_regmap,
227	.set_mode = mp886x_set_mode,
228	.get_mode = mp886x_get_mode,
229	.set_ramp_delay = regulator_set_ramp_delay_regmap,
230};
231
232static const struct mp886x_cfg_info mp8867_ci = {
233	.rops = &mp8867_regulator_ops,
234	.slew_rates = {
235		64000,
236		32000,
237		16000,
238		8000,
239		4000,
240		2000,
241		1000,
242		500,
243	},
244	.switch_freq = {
245		500000,
246		750000,
247		1000000,
248		1500000,
249	},
250	.fs_reg = MP886X_SYSCNTLREG1,
251	.fs_shift = 1,
252};
253
254static int mp886x_regulator_register(struct mp886x_device_info *di,
255				     struct regulator_config *config)
256{
257	struct regulator_desc *rdesc = &di->desc;
258	struct regulator_dev *rdev;
259
260	rdesc->name = "mp886x-reg";
261	rdesc->supply_name = "vin";
262	rdesc->ops = di->ci->rops;
263	rdesc->type = REGULATOR_VOLTAGE;
264	rdesc->n_voltages = 128;
265	rdesc->enable_reg = MP886X_SYSCNTLREG1;
266	rdesc->enable_mask = MP886X_EN;
267	rdesc->min_uV = 600000;
268	rdesc->uV_step = 10000;
269	rdesc->vsel_reg = MP886X_VSEL;
270	rdesc->vsel_mask = 0x3f;
271	rdesc->ramp_reg = MP886X_SYSCNTLREG1;
272	rdesc->ramp_mask = MP886X_SLEW_MASK;
273	rdesc->ramp_delay_table = di->ci->slew_rates;
274	rdesc->n_ramp_values = ARRAY_SIZE(di->ci->slew_rates);
275	rdesc->owner = THIS_MODULE;
276
277	rdev = devm_regulator_register(di->dev, &di->desc, config);
278	if (IS_ERR(rdev))
279		return PTR_ERR(rdev);
280	di->sel = rdesc->ops->get_voltage_sel(rdev);
281	return 0;
282}
283
284static const struct regmap_config mp886x_regmap_config = {
285	.reg_bits = 8,
286	.val_bits = 8,
287};
288
289static int mp886x_i2c_probe(struct i2c_client *client)
290{
291	struct device *dev = &client->dev;
292	struct device_node *np = dev->of_node;
293	struct mp886x_device_info *di;
294	struct regulator_config config = { };
295	struct regmap *regmap;
296	u32 freq;
297	int ret;
298
299	di = devm_kzalloc(dev, sizeof(struct mp886x_device_info), GFP_KERNEL);
300	if (!di)
301		return -ENOMEM;
302
303	di->regulator = of_get_regulator_init_data(dev, np, &di->desc);
304	if (!di->regulator) {
305		dev_err(dev, "Platform data not found!\n");
306		return -EINVAL;
307	}
308
309	ret = of_property_read_u32_array(np, "mps,fb-voltage-divider",
310					 di->r, 2);
311	if (ret)
312		return ret;
313
314	di->en_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_HIGH);
315	if (IS_ERR(di->en_gpio))
316		return PTR_ERR(di->en_gpio);
317
318	di->ci = i2c_get_match_data(client);
319	di->dev = dev;
320
321	regmap = devm_regmap_init_i2c(client, &mp886x_regmap_config);
322	if (IS_ERR(regmap)) {
323		dev_err(dev, "Failed to allocate regmap!\n");
324		return PTR_ERR(regmap);
325	}
326	i2c_set_clientdata(client, di);
327
328	config.dev = di->dev;
329	config.init_data = di->regulator;
330	config.regmap = regmap;
331	config.driver_data = di;
332	config.of_node = np;
333
334	if (!of_property_read_u32(np, "mps,switch-frequency-hz", &freq))
335		mp886x_set_switch_freq(di, regmap, freq);
336
337	ret = mp886x_regulator_register(di, &config);
338	if (ret < 0)
339		dev_err(dev, "Failed to register regulator!\n");
340	return ret;
341}
342
343static const struct of_device_id mp886x_dt_ids[] = {
344	{ .compatible = "mps,mp8867", .data = &mp8867_ci },
345	{ .compatible = "mps,mp8869", .data = &mp8869_ci },
346	{ }
347};
348MODULE_DEVICE_TABLE(of, mp886x_dt_ids);
349
350static const struct i2c_device_id mp886x_id[] = {
351	{ "mp886x", (kernel_ulong_t)&mp8869_ci },
352	{ },
353};
354MODULE_DEVICE_TABLE(i2c, mp886x_id);
355
356static struct i2c_driver mp886x_regulator_driver = {
357	.driver = {
358		.name = "mp886x-regulator",
359		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
360		.of_match_table = mp886x_dt_ids,
361	},
362	.probe = mp886x_i2c_probe,
363	.id_table = mp886x_id,
364};
365module_i2c_driver(mp886x_regulator_driver);
366
367MODULE_AUTHOR("Jisheng Zhang <jszhang@kernel.org>");
368MODULE_DESCRIPTION("MP886x regulator driver");
369MODULE_LICENSE("GPL v2");
370