summaryrefslogtreecommitdiff
path: root/drivers/regulator/rt6245-regulator.c
blob: 8721d11c796422019a9be1e1c6f508e480a63888 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
// SPDX-License-Identifier: GPL-2.0+

#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/of_regulator.h>

#define RT6245_VIRT_OCLIMIT	0x00
#define RT6245_VIRT_OTLEVEL	0x01
#define RT6245_VIRT_PGDLYTIME	0x02
#define RT6245_VIRT_SLEWRATE	0x03
#define RT6245_VIRT_SWFREQ	0x04
#define RT6245_VIRT_VOUT	0x05

#define RT6245_VOUT_MASK	GENMASK(6, 0)
#define RT6245_SLEW_MASK	GENMASK(2, 0)
#define RT6245_CHKSUM_MASK	BIT(7)
#define RT6245_CODE_MASK	GENMASK(6, 0)

/* HW Enable + Soft start time */
#define RT6245_ENTIME_IN_US	5000

#define RT6245_VOUT_MINUV	437500
#define RT6245_VOUT_MAXUV	1387500
#define RT6245_VOUT_STEPUV	12500
#define RT6245_NUM_VOUT		((RT6245_VOUT_MAXUV - RT6245_VOUT_MINUV) / RT6245_VOUT_STEPUV + 1)

struct rt6245_priv {
	struct gpio_desc *enable_gpio;
	bool enable_state;
};

static int rt6245_enable(struct regulator_dev *rdev)
{
	struct rt6245_priv *priv = rdev_get_drvdata(rdev);
	struct regmap *regmap = rdev_get_regmap(rdev);
	int ret;

	if (!priv->enable_gpio)
		return 0;

	gpiod_direction_output(priv->enable_gpio, 1);
	usleep_range(RT6245_ENTIME_IN_US, RT6245_ENTIME_IN_US + 1000);

	regcache_cache_only(regmap, false);
	ret = regcache_sync(regmap);
	if (ret)
		return ret;

	priv->enable_state = true;
	return 0;
}

static int rt6245_disable(struct regulator_dev *rdev)
{
	struct rt6245_priv *priv = rdev_get_drvdata(rdev);
	struct regmap *regmap = rdev_get_regmap(rdev);

	if (!priv->enable_gpio)
		return -EINVAL;

	regcache_cache_only(regmap, true);
	regcache_mark_dirty(regmap);

	gpiod_direction_output(priv->enable_gpio, 0);

	priv->enable_state = false;
	return 0;
}

static int rt6245_is_enabled(struct regulator_dev *rdev)
{
	struct rt6245_priv *priv = rdev_get_drvdata(rdev);

	return priv->enable_state ? 1 : 0;
}

static const struct regulator_ops rt6245_regulator_ops = {
	.list_voltage = regulator_list_voltage_linear,
	.set_voltage_sel = regulator_set_voltage_sel_regmap,
	.get_voltage_sel = regulator_get_voltage_sel_regmap,
	.set_ramp_delay = regulator_set_ramp_delay_regmap,
	.enable = rt6245_enable,
	.disable = rt6245_disable,
	.is_enabled = rt6245_is_enabled,
};

/* ramp delay dividend is 12500 uV/uS, and divisor from 1 to 8 */
static const unsigned int rt6245_ramp_delay_table[] = {
	12500, 6250, 4167, 3125, 2500, 2083, 1786, 1562
};

static const struct regulator_desc rt6245_regulator_desc = {
	.name = "rt6245-regulator",
	.ops = &rt6245_regulator_ops,
	.type = REGULATOR_VOLTAGE,
	.min_uV = RT6245_VOUT_MINUV,
	.uV_step = RT6245_VOUT_STEPUV,
	.n_voltages = RT6245_NUM_VOUT,
	.ramp_delay_table = rt6245_ramp_delay_table,
	.n_ramp_values = ARRAY_SIZE(rt6245_ramp_delay_table),
	.owner = THIS_MODULE,
	.vsel_reg = RT6245_VIRT_VOUT,
	.vsel_mask = RT6245_VOUT_MASK,
	.ramp_reg = RT6245_VIRT_SLEWRATE,
	.ramp_mask = RT6245_SLEW_MASK,
};

static int rt6245_init_device_properties(struct device *dev)
{
	const struct {
		const char *name;
		unsigned int reg;
	} rt6245_props[] = {
		{ "richtek,oc-level-select",  RT6245_VIRT_OCLIMIT },
		{ "richtek,ot-level-select", RT6245_VIRT_OTLEVEL },
		{ "richtek,pgdly-time-select", RT6245_VIRT_PGDLYTIME },
		{ "richtek,switch-freq-select", RT6245_VIRT_SWFREQ }
	};
	struct regmap *regmap = dev_get_regmap(dev, NULL);
	u8 propval;
	int i, ret;

	for (i = 0; i < ARRAY_SIZE(rt6245_props); i++) {
		ret = device_property_read_u8(dev, rt6245_props[i].name, &propval);
		if (ret)
			continue;

		ret = regmap_write(regmap, rt6245_props[i].reg, propval);
		if (ret) {
			dev_err(dev, "Fail to apply [%s:%d]\n", rt6245_props[i].name, propval);
			return ret;
		}
	}

	return 0;
}

static int rt6245_reg_write(void *context, unsigned int reg, unsigned int val)
{
	struct i2c_client *i2c = context;
	static const u8 func_base[] = { 0x6F, 0x73, 0x78, 0x61, 0x7C, 0 };
	unsigned int code, bit_count;

	code = func_base[reg];
	code += val;

	/* xor checksum for bit 6 to 0 */
	bit_count = hweight8(code & RT6245_CODE_MASK);
	if (bit_count % 2)
		code |= RT6245_CHKSUM_MASK;
	else
		code &= ~RT6245_CHKSUM_MASK;

	return i2c_smbus_write_byte(i2c, code);
}

static const struct reg_default rt6245_reg_defaults[] = {
	/* Default over current 14A */
	{ RT6245_VIRT_OCLIMIT, 2 },
	/* Default over temperature 150'c */
	{ RT6245_VIRT_OTLEVEL, 0 },
	/* Default power good delay time 10us */
	{ RT6245_VIRT_PGDLYTIME, 1 },
	/* Default slewrate 12.5mV/uS */
	{ RT6245_VIRT_SLEWRATE, 0 },
	/* Default switch frequency 800KHz */
	{ RT6245_VIRT_SWFREQ, 1 },
	/* Default voltage 750mV */
	{ RT6245_VIRT_VOUT, 0x19 }
};

static const struct regmap_config rt6245_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.max_register = RT6245_VIRT_VOUT,
	.cache_type = REGCACHE_FLAT,
	.reg_defaults = rt6245_reg_defaults,
	.num_reg_defaults = ARRAY_SIZE(rt6245_reg_defaults),
	.reg_write = rt6245_reg_write,
};

static int rt6245_probe(struct i2c_client *i2c)
{
	struct rt6245_priv *priv;
	struct regmap *regmap;
	struct regulator_config regulator_cfg = {};
	struct regulator_dev *rdev;
	int ret;

	priv = devm_kzalloc(&i2c->dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
		return -ENOMEM;

	priv->enable_state = true;

	priv->enable_gpio = devm_gpiod_get_optional(&i2c->dev, "enable", GPIOD_OUT_HIGH);
	if (IS_ERR(priv->enable_gpio)) {
		dev_err(&i2c->dev, "Failed to get 'enable' gpio\n");
		return PTR_ERR(priv->enable_gpio);
	}

	usleep_range(RT6245_ENTIME_IN_US, RT6245_ENTIME_IN_US + 1000);

	regmap = devm_regmap_init(&i2c->dev, NULL, i2c, &rt6245_regmap_config);
	if (IS_ERR(regmap)) {
		dev_err(&i2c->dev, "Failed to initialize the regmap\n");
		return PTR_ERR(regmap);
	}

	ret = rt6245_init_device_properties(&i2c->dev);
	if (ret) {
		dev_err(&i2c->dev, "Failed to initialize device properties\n");
		return ret;
	}

	regulator_cfg.dev = &i2c->dev;
	regulator_cfg.of_node = i2c->dev.of_node;
	regulator_cfg.regmap = regmap;
	regulator_cfg.driver_data = priv;
	regulator_cfg.init_data = of_get_regulator_init_data(&i2c->dev, i2c->dev.of_node,
							     &rt6245_regulator_desc);
	rdev = devm_regulator_register(&i2c->dev, &rt6245_regulator_desc, &regulator_cfg);
	if (IS_ERR(rdev)) {
		dev_err(&i2c->dev, "Failed to register regulator\n");
		return PTR_ERR(rdev);
	}

	return 0;
}

static const struct of_device_id __maybe_unused rt6245_of_match_table[] = {
	{ .compatible = "richtek,rt6245", },
	{}
};
MODULE_DEVICE_TABLE(of, rt6245_of_match_table);

static struct i2c_driver rt6245_driver = {
	.driver = {
		.name = "rt6245",
		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
		.of_match_table = rt6245_of_match_table,
	},
	.probe_new = rt6245_probe,
};
module_i2c_driver(rt6245_driver);

MODULE_AUTHOR("ChiYuan Huang <cy_huang@richtek.com>");
MODULE_DESCRIPTION("Richtek RT6245 Regulator Driver");
MODULE_LICENSE("GPL v2");