aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/regulator/rt4801-regulator.c
blob: 7a87788d3f0922399d54d88a4e35573aa5931001 (plain) (blame)
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
// SPDX-License-Identifier: GPL-2.0+

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

#define RT4801_REG_VOP	0x00
#define RT4801_REG_VON	0x01
#define RT4801_REG_APPS	0x03

#define VOUT_MASK	0x1F

#define MIN_UV		4000000
#define STEP_UV		100000
#define MAX_UV		6000000
#define N_VOLTAGES	((MAX_UV - MIN_UV) / STEP_UV + 1)

#define DSV_OUT_POS	0
#define DSV_OUT_NEG	1
#define DSV_OUT_MAX	2

#define DSVP_ENABLE	BIT(0)
#define DSVN_ENABLE	BIT(1)
#define DSVALL_ENABLE	(DSVP_ENABLE | DSVN_ENABLE)

struct rt4801_priv {
	struct device *dev;
	struct gpio_descs *enable_gpios;
	unsigned int enable_flag;
	unsigned int volt_sel[DSV_OUT_MAX];
};

static int rt4801_set_voltage_sel(struct regulator_dev *rdev, unsigned int selector)
{
	struct rt4801_priv *priv = rdev_get_drvdata(rdev);
	int id = rdev_get_id(rdev), ret;

	if (priv->enable_flag & BIT(id)) {
		ret = regulator_set_voltage_sel_regmap(rdev, selector);
		if (ret)
			return ret;
	}

	priv->volt_sel[id] = selector;
	return 0;
}

static int rt4801_get_voltage_sel(struct regulator_dev *rdev)
{
	struct rt4801_priv *priv = rdev_get_drvdata(rdev);
	int id = rdev_get_id(rdev);

	if (priv->enable_flag & BIT(id))
		return regulator_get_voltage_sel_regmap(rdev);

	return priv->volt_sel[id];
}

static int rt4801_enable(struct regulator_dev *rdev)
{
	struct rt4801_priv *priv = rdev_get_drvdata(rdev);
	struct gpio_descs *gpios = priv->enable_gpios;
	int id = rdev_get_id(rdev), ret;

	if (!gpios || gpios->ndescs <= id) {
		dev_warn(&rdev->dev, "no dedicated gpio can control\n");
		goto bypass_gpio;
	}

	gpiod_set_value(gpios->desc[id], 1);

bypass_gpio:
	ret = regmap_write(rdev->regmap, rdev->desc->vsel_reg, priv->volt_sel[id]);
	if (ret)
		return ret;

	priv->enable_flag |= BIT(id);
	return 0;
}

static int rt4801_disable(struct regulator_dev *rdev)
{
	struct rt4801_priv *priv = rdev_get_drvdata(rdev);
	struct gpio_descs *gpios = priv->enable_gpios;
	int id = rdev_get_id(rdev);

	if (!gpios || gpios->ndescs <= id) {
		dev_warn(&rdev->dev, "no dedicated gpio can control\n");
		goto bypass_gpio;
	}

	gpiod_set_value(gpios->desc[id], 0);

bypass_gpio:
	priv->enable_flag &= ~BIT(id);
	return 0;
}

static int rt4801_is_enabled(struct regulator_dev *rdev)
{
	struct rt4801_priv *priv = rdev_get_drvdata(rdev);
	int id = rdev_get_id(rdev);

	return !!(priv->enable_flag & BIT(id));
}

static const struct regulator_ops rt4801_regulator_ops = {
	.list_voltage = regulator_list_voltage_linear,
	.set_voltage_sel = rt4801_set_voltage_sel,
	.get_voltage_sel = rt4801_get_voltage_sel,
	.enable = rt4801_enable,
	.disable = rt4801_disable,
	.is_enabled = rt4801_is_enabled,
};

static const struct regulator_desc rt4801_regulator_descs[] = {
	{
		.name = "DSVP",
		.ops = &rt4801_regulator_ops,
		.of_match = of_match_ptr("DSVP"),
		.type = REGULATOR_VOLTAGE,
		.id = DSV_OUT_POS,
		.min_uV = MIN_UV,
		.uV_step = STEP_UV,
		.n_voltages = N_VOLTAGES,
		.owner = THIS_MODULE,
		.vsel_reg = RT4801_REG_VOP,
		.vsel_mask = VOUT_MASK,
	},
	{
		.name = "DSVN",
		.ops = &rt4801_regulator_ops,
		.of_match = of_match_ptr("DSVN"),
		.type = REGULATOR_VOLTAGE,
		.id = DSV_OUT_NEG,
		.min_uV = MIN_UV,
		.uV_step = STEP_UV,
		.n_voltages = N_VOLTAGES,
		.owner = THIS_MODULE,
		.vsel_reg = RT4801_REG_VON,
		.vsel_mask = VOUT_MASK,
	},
};

static const struct regmap_config rt4801_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.max_register = RT4801_REG_APPS,
};

static int rt4801_probe(struct i2c_client *i2c)
{
	struct rt4801_priv *priv;
	struct regmap *regmap;
	int i;

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

	priv->dev = &i2c->dev;
	/* bootloader will on, driver only reconfigure enable to all output high */
	priv->enable_flag = DSVALL_ENABLE;

	regmap = devm_regmap_init_i2c(i2c, &rt4801_regmap_config);
	if (IS_ERR(regmap)) {
		dev_err(&i2c->dev, "Failed to init regmap\n");
		return PTR_ERR(regmap);
	}

	priv->enable_gpios = devm_gpiod_get_array_optional(&i2c->dev, "enable", GPIOD_OUT_HIGH);
	if (IS_ERR(priv->enable_gpios)) {
		dev_err(&i2c->dev, "Failed to get gpios\n");
		return PTR_ERR(priv->enable_gpios);
	}

	for (i = 0; i < DSV_OUT_MAX; i++) {
		const struct regulator_desc *desc = rt4801_regulator_descs + i;
		struct regulator_config config = { .dev = &i2c->dev, .driver_data = priv,
						   .regmap = regmap, };
		struct regulator_dev *rdev;
		unsigned int val;
		int ret;

		/* initialize volt_sel variable */
		ret = regmap_read(regmap, desc->vsel_reg, &val);
		if (ret)
			return ret;

		priv->volt_sel[i] = val & desc->vsel_mask;

		rdev = devm_regulator_register(&i2c->dev, desc, &config);
		if (IS_ERR(rdev)) {
			dev_err(&i2c->dev, "Failed to register [%d] regulator\n", i);
			return PTR_ERR(rdev);
		}
	}

	return 0;
}

static const struct of_device_id __maybe_unused rt4801_of_id[] = {
	{ .compatible = "richtek,rt4801", },
	{ },
};
MODULE_DEVICE_TABLE(of, rt4801_of_id);

static struct i2c_driver rt4801_driver = {
	.driver = {
		.name = "rt4801",
		.of_match_table = of_match_ptr(rt4801_of_id),
	},
	.probe_new = rt4801_probe,
};
module_i2c_driver(rt4801_driver);

MODULE_AUTHOR("ChiYuan Hwang <cy_huang@richtek.com>");
MODULE_DESCRIPTION("Richtek RT4801 Display Bias Driver");
MODULE_LICENSE("GPL v2");