xref: /openbmc/linux/drivers/mfd/ti-lmu.c (revision ba61bb17)
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.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/of_gpio.h>
25 #include <linux/slab.h>
26 
27 struct ti_lmu_data {
28 	struct mfd_cell *cells;
29 	int num_cells;
30 	unsigned int max_register;
31 };
32 
33 static int ti_lmu_enable_hw(struct ti_lmu *lmu, enum ti_lmu_id id)
34 {
35 	int ret;
36 
37 	if (gpio_is_valid(lmu->en_gpio)) {
38 		ret = devm_gpio_request_one(lmu->dev, lmu->en_gpio,
39 					    GPIOF_OUT_INIT_HIGH, "lmu_hwen");
40 		if (ret) {
41 			dev_err(lmu->dev, "Can not request enable GPIO: %d\n",
42 				ret);
43 			return ret;
44 		}
45 	}
46 
47 	/* Delay about 1ms after HW enable pin control */
48 	usleep_range(1000, 1500);
49 
50 	/* LM3631 has additional power up sequence - enable LCD_EN bit. */
51 	if (id == LM3631) {
52 		return regmap_update_bits(lmu->regmap, LM3631_REG_DEVCTRL,
53 					  LM3631_LCD_EN_MASK,
54 					  LM3631_LCD_EN_MASK);
55 	}
56 
57 	return 0;
58 }
59 
60 static void ti_lmu_disable_hw(struct ti_lmu *lmu)
61 {
62 	if (gpio_is_valid(lmu->en_gpio))
63 		gpio_set_value(lmu->en_gpio, 0);
64 }
65 
66 static struct mfd_cell lm3532_devices[] = {
67 	{
68 		.name          = "ti-lmu-backlight",
69 		.id            = LM3532,
70 		.of_compatible = "ti,lm3532-backlight",
71 	},
72 };
73 
74 #define LM363X_REGULATOR(_id)			\
75 {						\
76 	.name          = "lm363x-regulator",	\
77 	.id            = _id,			\
78 	.of_compatible = "ti,lm363x-regulator",	\
79 }						\
80 
81 static struct mfd_cell lm3631_devices[] = {
82 	LM363X_REGULATOR(LM3631_BOOST),
83 	LM363X_REGULATOR(LM3631_LDO_CONT),
84 	LM363X_REGULATOR(LM3631_LDO_OREF),
85 	LM363X_REGULATOR(LM3631_LDO_POS),
86 	LM363X_REGULATOR(LM3631_LDO_NEG),
87 	{
88 		.name          = "ti-lmu-backlight",
89 		.id            = LM3631,
90 		.of_compatible = "ti,lm3631-backlight",
91 	},
92 };
93 
94 static struct mfd_cell lm3632_devices[] = {
95 	LM363X_REGULATOR(LM3632_BOOST),
96 	LM363X_REGULATOR(LM3632_LDO_POS),
97 	LM363X_REGULATOR(LM3632_LDO_NEG),
98 	{
99 		.name          = "ti-lmu-backlight",
100 		.id            = LM3632,
101 		.of_compatible = "ti,lm3632-backlight",
102 	},
103 };
104 
105 static struct mfd_cell lm3633_devices[] = {
106 	{
107 		.name          = "ti-lmu-backlight",
108 		.id            = LM3633,
109 		.of_compatible = "ti,lm3633-backlight",
110 	},
111 	{
112 		.name          = "lm3633-leds",
113 		.of_compatible = "ti,lm3633-leds",
114 	},
115 	/* Monitoring driver for open/short circuit detection */
116 	{
117 		.name          = "ti-lmu-fault-monitor",
118 		.id            = LM3633,
119 		.of_compatible = "ti,lm3633-fault-monitor",
120 	},
121 };
122 
123 static struct mfd_cell lm3695_devices[] = {
124 	{
125 		.name          = "ti-lmu-backlight",
126 		.id            = LM3695,
127 		.of_compatible = "ti,lm3695-backlight",
128 	},
129 };
130 
131 static struct mfd_cell lm3697_devices[] = {
132 	{
133 		.name          = "ti-lmu-backlight",
134 		.id            = LM3697,
135 		.of_compatible = "ti,lm3697-backlight",
136 	},
137 	/* Monitoring driver for open/short circuit detection */
138 	{
139 		.name          = "ti-lmu-fault-monitor",
140 		.id            = LM3697,
141 		.of_compatible = "ti,lm3697-fault-monitor",
142 	},
143 };
144 
145 #define TI_LMU_DATA(chip, max_reg)		\
146 static const struct ti_lmu_data chip##_data =	\
147 {						\
148 	.cells = chip##_devices,		\
149 	.num_cells = ARRAY_SIZE(chip##_devices),\
150 	.max_register = max_reg,		\
151 }						\
152 
153 TI_LMU_DATA(lm3532, LM3532_MAX_REG);
154 TI_LMU_DATA(lm3631, LM3631_MAX_REG);
155 TI_LMU_DATA(lm3632, LM3632_MAX_REG);
156 TI_LMU_DATA(lm3633, LM3633_MAX_REG);
157 TI_LMU_DATA(lm3695, LM3695_MAX_REG);
158 TI_LMU_DATA(lm3697, LM3697_MAX_REG);
159 
160 static const struct of_device_id ti_lmu_of_match[] = {
161 	{ .compatible = "ti,lm3532", .data = &lm3532_data },
162 	{ .compatible = "ti,lm3631", .data = &lm3631_data },
163 	{ .compatible = "ti,lm3632", .data = &lm3632_data },
164 	{ .compatible = "ti,lm3633", .data = &lm3633_data },
165 	{ .compatible = "ti,lm3695", .data = &lm3695_data },
166 	{ .compatible = "ti,lm3697", .data = &lm3697_data },
167 	{ }
168 };
169 MODULE_DEVICE_TABLE(of, ti_lmu_of_match);
170 
171 static int ti_lmu_probe(struct i2c_client *cl, const struct i2c_device_id *id)
172 {
173 	struct device *dev = &cl->dev;
174 	const struct of_device_id *match;
175 	const struct ti_lmu_data *data;
176 	struct regmap_config regmap_cfg;
177 	struct ti_lmu *lmu;
178 	int ret;
179 
180 	match = of_match_device(ti_lmu_of_match, dev);
181 	if (!match)
182 		return -ENODEV;
183 	/*
184 	 * Get device specific data from of_match table.
185 	 * This data is defined by using TI_LMU_DATA() macro.
186 	 */
187 	data = (struct ti_lmu_data *)match->data;
188 
189 	lmu = devm_kzalloc(dev, sizeof(*lmu), GFP_KERNEL);
190 	if (!lmu)
191 		return -ENOMEM;
192 
193 	lmu->dev = &cl->dev;
194 
195 	/* Setup regmap */
196 	memset(&regmap_cfg, 0, sizeof(struct regmap_config));
197 	regmap_cfg.reg_bits = 8;
198 	regmap_cfg.val_bits = 8;
199 	regmap_cfg.name = id->name;
200 	regmap_cfg.max_register = data->max_register;
201 
202 	lmu->regmap = devm_regmap_init_i2c(cl, &regmap_cfg);
203 	if (IS_ERR(lmu->regmap))
204 		return PTR_ERR(lmu->regmap);
205 
206 	/* HW enable pin control and additional power up sequence if required */
207 	lmu->en_gpio = of_get_named_gpio(dev->of_node, "enable-gpios", 0);
208 	ret = ti_lmu_enable_hw(lmu, id->driver_data);
209 	if (ret)
210 		return ret;
211 
212 	/*
213 	 * Fault circuit(open/short) can be detected by ti-lmu-fault-monitor.
214 	 * After fault detection is done, some devices should re-initialize
215 	 * configuration. The notifier enables such kind of handling.
216 	 */
217 	BLOCKING_INIT_NOTIFIER_HEAD(&lmu->notifier);
218 
219 	i2c_set_clientdata(cl, lmu);
220 
221 	return mfd_add_devices(lmu->dev, 0, data->cells,
222 			       data->num_cells, NULL, 0, NULL);
223 }
224 
225 static int ti_lmu_remove(struct i2c_client *cl)
226 {
227 	struct ti_lmu *lmu = i2c_get_clientdata(cl);
228 
229 	ti_lmu_disable_hw(lmu);
230 	mfd_remove_devices(lmu->dev);
231 	return 0;
232 }
233 
234 static const struct i2c_device_id ti_lmu_ids[] = {
235 	{ "lm3532", LM3532 },
236 	{ "lm3631", LM3631 },
237 	{ "lm3632", LM3632 },
238 	{ "lm3633", LM3633 },
239 	{ "lm3695", LM3695 },
240 	{ "lm3697", LM3697 },
241 	{ }
242 };
243 MODULE_DEVICE_TABLE(i2c, ti_lmu_ids);
244 
245 static struct i2c_driver ti_lmu_driver = {
246 	.probe = ti_lmu_probe,
247 	.remove = ti_lmu_remove,
248 	.driver = {
249 		.name = "ti-lmu",
250 		.of_match_table = ti_lmu_of_match,
251 	},
252 	.id_table = ti_lmu_ids,
253 };
254 
255 module_i2c_driver(ti_lmu_driver);
256 
257 MODULE_DESCRIPTION("TI LMU MFD Core Driver");
258 MODULE_AUTHOR("Milo Kim");
259 MODULE_LICENSE("GPL v2");
260