xref: /openbmc/linux/drivers/mfd/ti-lmu.c (revision bb3982b4)
1 /*
2  * TI LMU (Lighting Management Unit) Core Driver
3  *
4  * Copyright 2017 Texas Instruments
5  *
6  * Author: Milo Kim <milo.kim@ti.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #include <linux/delay.h>
14 #include <linux/err.h>
15 #include <linux/gpio/consumer.h>
16 #include <linux/i2c.h>
17 #include <linux/kernel.h>
18 #include <linux/mfd/core.h>
19 #include <linux/mfd/ti-lmu.h>
20 #include <linux/mfd/ti-lmu-register.h>
21 #include <linux/module.h>
22 #include <linux/of.h>
23 #include <linux/of_device.h>
24 #include <linux/slab.h>
25 
26 struct ti_lmu_data {
27 	const struct mfd_cell *cells;
28 	int num_cells;
29 	unsigned int max_register;
30 };
31 
32 static int ti_lmu_enable_hw(struct ti_lmu *lmu, enum ti_lmu_id id)
33 {
34 	if (lmu->en_gpio)
35 		gpiod_set_value(lmu->en_gpio, 1);
36 
37 	/* Delay about 1ms after HW enable pin control */
38 	usleep_range(1000, 1500);
39 
40 	/* LM3631 has additional power up sequence - enable LCD_EN bit. */
41 	if (id == LM3631) {
42 		return regmap_update_bits(lmu->regmap, LM3631_REG_DEVCTRL,
43 					  LM3631_LCD_EN_MASK,
44 					  LM3631_LCD_EN_MASK);
45 	}
46 
47 	return 0;
48 }
49 
50 static void ti_lmu_disable_hw(void *data)
51 {
52 	struct ti_lmu *lmu = data;
53 	if (lmu->en_gpio)
54 		gpiod_set_value(lmu->en_gpio, 0);
55 }
56 
57 #define LM363X_REGULATOR(_id)			\
58 {						\
59 	.name          = "lm363x-regulator",	\
60 	.id            = _id,			\
61 	.of_compatible = "ti,lm363x-regulator",	\
62 }						\
63 
64 static const struct mfd_cell lm3631_devices[] = {
65 	LM363X_REGULATOR(LM3631_BOOST),
66 	LM363X_REGULATOR(LM3631_LDO_CONT),
67 	LM363X_REGULATOR(LM3631_LDO_OREF),
68 	LM363X_REGULATOR(LM3631_LDO_POS),
69 	LM363X_REGULATOR(LM3631_LDO_NEG),
70 	{
71 		.name          = "ti-lmu-backlight",
72 		.id            = LM3631,
73 		.of_compatible = "ti,lm3631-backlight",
74 	},
75 };
76 
77 static const struct mfd_cell lm3632_devices[] = {
78 	LM363X_REGULATOR(LM3632_BOOST),
79 	LM363X_REGULATOR(LM3632_LDO_POS),
80 	LM363X_REGULATOR(LM3632_LDO_NEG),
81 	{
82 		.name          = "ti-lmu-backlight",
83 		.id            = LM3632,
84 		.of_compatible = "ti,lm3632-backlight",
85 	},
86 };
87 
88 static const struct mfd_cell lm3633_devices[] = {
89 	{
90 		.name          = "ti-lmu-backlight",
91 		.id            = LM3633,
92 		.of_compatible = "ti,lm3633-backlight",
93 	},
94 	{
95 		.name          = "lm3633-leds",
96 		.of_compatible = "ti,lm3633-leds",
97 	},
98 	/* Monitoring driver for open/short circuit detection */
99 	{
100 		.name          = "ti-lmu-fault-monitor",
101 		.id            = LM3633,
102 		.of_compatible = "ti,lm3633-fault-monitor",
103 	},
104 };
105 
106 static const struct mfd_cell lm3695_devices[] = {
107 	{
108 		.name          = "ti-lmu-backlight",
109 		.id            = LM3695,
110 		.of_compatible = "ti,lm3695-backlight",
111 	},
112 };
113 
114 static const struct mfd_cell lm3697_devices[] = {
115 	{
116 		.name          = "ti-lmu-backlight",
117 		.id            = LM3697,
118 		.of_compatible = "ti,lm3697-backlight",
119 	},
120 	/* Monitoring driver for open/short circuit detection */
121 	{
122 		.name          = "ti-lmu-fault-monitor",
123 		.id            = LM3697,
124 		.of_compatible = "ti,lm3697-fault-monitor",
125 	},
126 };
127 
128 #define TI_LMU_DATA(chip, max_reg)		\
129 static const struct ti_lmu_data chip##_data =	\
130 {						\
131 	.cells = chip##_devices,		\
132 	.num_cells = ARRAY_SIZE(chip##_devices),\
133 	.max_register = max_reg,		\
134 }						\
135 
136 TI_LMU_DATA(lm3631, LM3631_MAX_REG);
137 TI_LMU_DATA(lm3632, LM3632_MAX_REG);
138 TI_LMU_DATA(lm3633, LM3633_MAX_REG);
139 TI_LMU_DATA(lm3695, LM3695_MAX_REG);
140 TI_LMU_DATA(lm3697, LM3697_MAX_REG);
141 
142 static int ti_lmu_probe(struct i2c_client *cl, const struct i2c_device_id *id)
143 {
144 	struct device *dev = &cl->dev;
145 	const struct ti_lmu_data *data;
146 	struct regmap_config regmap_cfg;
147 	struct ti_lmu *lmu;
148 	int ret;
149 
150 	/*
151 	 * Get device specific data from of_match table.
152 	 * This data is defined by using TI_LMU_DATA() macro.
153 	 */
154 	data = of_device_get_match_data(dev);
155 	if (!data)
156 		return -ENODEV;
157 
158 	lmu = devm_kzalloc(dev, sizeof(*lmu), GFP_KERNEL);
159 	if (!lmu)
160 		return -ENOMEM;
161 
162 	lmu->dev = &cl->dev;
163 
164 	/* Setup regmap */
165 	memset(&regmap_cfg, 0, sizeof(struct regmap_config));
166 	regmap_cfg.reg_bits = 8;
167 	regmap_cfg.val_bits = 8;
168 	regmap_cfg.name = id->name;
169 	regmap_cfg.max_register = data->max_register;
170 
171 	lmu->regmap = devm_regmap_init_i2c(cl, &regmap_cfg);
172 	if (IS_ERR(lmu->regmap))
173 		return PTR_ERR(lmu->regmap);
174 
175 	/* HW enable pin control and additional power up sequence if required */
176 	lmu->en_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_HIGH);
177 	if (IS_ERR(lmu->en_gpio)) {
178 		ret = PTR_ERR(lmu->en_gpio);
179 		dev_err(dev, "Can not request enable GPIO: %d\n", ret);
180 		return ret;
181 	}
182 
183 	ret = ti_lmu_enable_hw(lmu, id->driver_data);
184 	if (ret)
185 		return ret;
186 
187 	ret = devm_add_action_or_reset(dev, ti_lmu_disable_hw, lmu);
188 	if (ret)
189 		return ret;
190 
191 	/*
192 	 * Fault circuit(open/short) can be detected by ti-lmu-fault-monitor.
193 	 * After fault detection is done, some devices should re-initialize
194 	 * configuration. The notifier enables such kind of handling.
195 	 */
196 	BLOCKING_INIT_NOTIFIER_HEAD(&lmu->notifier);
197 
198 	i2c_set_clientdata(cl, lmu);
199 
200 	return devm_mfd_add_devices(lmu->dev, 0, data->cells,
201 				    data->num_cells, NULL, 0, NULL);
202 }
203 
204 static const struct of_device_id ti_lmu_of_match[] = {
205 	{ .compatible = "ti,lm3631", .data = &lm3631_data },
206 	{ .compatible = "ti,lm3632", .data = &lm3632_data },
207 	{ .compatible = "ti,lm3633", .data = &lm3633_data },
208 	{ .compatible = "ti,lm3695", .data = &lm3695_data },
209 	{ .compatible = "ti,lm3697", .data = &lm3697_data },
210 	{ }
211 };
212 MODULE_DEVICE_TABLE(of, ti_lmu_of_match);
213 
214 static const struct i2c_device_id ti_lmu_ids[] = {
215 	{ "lm3631", LM3631 },
216 	{ "lm3632", LM3632 },
217 	{ "lm3633", LM3633 },
218 	{ "lm3695", LM3695 },
219 	{ "lm3697", LM3697 },
220 	{ }
221 };
222 MODULE_DEVICE_TABLE(i2c, ti_lmu_ids);
223 
224 static struct i2c_driver ti_lmu_driver = {
225 	.probe = ti_lmu_probe,
226 	.driver = {
227 		.name = "ti-lmu",
228 		.of_match_table = ti_lmu_of_match,
229 	},
230 	.id_table = ti_lmu_ids,
231 };
232 
233 module_i2c_driver(ti_lmu_driver);
234 
235 MODULE_DESCRIPTION("TI LMU MFD Core Driver");
236 MODULE_AUTHOR("Milo Kim");
237 MODULE_LICENSE("GPL v2");
238