xref: /openbmc/linux/drivers/mfd/max77686.c (revision 12eb4683)
1 /*
2  * max77686.c - mfd core driver for the Maxim 77686
3  *
4  * Copyright (C) 2012 Samsung Electronics
5  * Chiwoong Byun <woong.byun@smasung.com>
6  * Jonghwa Lee <jonghwa3.lee@samsung.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 as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
21  *
22  * This driver is based on max8997.c
23  */
24 
25 #include <linux/export.h>
26 #include <linux/slab.h>
27 #include <linux/i2c.h>
28 #include <linux/pm_runtime.h>
29 #include <linux/module.h>
30 #include <linux/mfd/core.h>
31 #include <linux/mfd/max77686.h>
32 #include <linux/mfd/max77686-private.h>
33 #include <linux/err.h>
34 #include <linux/of.h>
35 
36 #define I2C_ADDR_RTC	(0x0C >> 1)
37 
38 static struct mfd_cell max77686_devs[] = {
39 	{ .name = "max77686-pmic", },
40 	{ .name = "max77686-rtc", },
41 	{ .name = "max77686-clk", },
42 };
43 
44 static struct regmap_config max77686_regmap_config = {
45 	.reg_bits = 8,
46 	.val_bits = 8,
47 };
48 
49 #ifdef CONFIG_OF
50 static struct of_device_id max77686_pmic_dt_match[] = {
51 	{.compatible = "maxim,max77686", .data = NULL},
52 	{},
53 };
54 
55 static struct max77686_platform_data *max77686_i2c_parse_dt_pdata(struct device
56 								  *dev)
57 {
58 	struct max77686_platform_data *pd;
59 
60 	pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
61 	if (!pd) {
62 		dev_err(dev, "could not allocate memory for pdata\n");
63 		return NULL;
64 	}
65 
66 	dev->platform_data = pd;
67 	return pd;
68 }
69 #else
70 static struct max77686_platform_data *max77686_i2c_parse_dt_pdata(struct device
71 								  *dev)
72 {
73 	return 0;
74 }
75 #endif
76 
77 static int max77686_i2c_probe(struct i2c_client *i2c,
78 			      const struct i2c_device_id *id)
79 {
80 	struct max77686_dev *max77686 = NULL;
81 	struct max77686_platform_data *pdata = dev_get_platdata(&i2c->dev);
82 	unsigned int data;
83 	int ret = 0;
84 
85 	if (i2c->dev.of_node)
86 		pdata = max77686_i2c_parse_dt_pdata(&i2c->dev);
87 
88 	if (!pdata) {
89 		dev_err(&i2c->dev, "No platform data found.\n");
90 		return -EIO;
91 	}
92 
93 	max77686 = devm_kzalloc(&i2c->dev,
94 				sizeof(struct max77686_dev), GFP_KERNEL);
95 	if (max77686 == NULL)
96 		return -ENOMEM;
97 
98 	i2c_set_clientdata(i2c, max77686);
99 	max77686->dev = &i2c->dev;
100 	max77686->i2c = i2c;
101 	max77686->type = id->driver_data;
102 
103 	max77686->wakeup = pdata->wakeup;
104 	max77686->irq_gpio = pdata->irq_gpio;
105 	max77686->irq = i2c->irq;
106 
107 	max77686->regmap = regmap_init_i2c(i2c, &max77686_regmap_config);
108 	if (IS_ERR(max77686->regmap)) {
109 		ret = PTR_ERR(max77686->regmap);
110 		dev_err(max77686->dev, "Failed to allocate register map: %d\n",
111 				ret);
112 		return ret;
113 	}
114 
115 	if (regmap_read(max77686->regmap,
116 			 MAX77686_REG_DEVICE_ID, &data) < 0) {
117 		dev_err(max77686->dev,
118 			"device not found on this channel (this is not an error)\n");
119 		return -ENODEV;
120 	} else
121 		dev_info(max77686->dev, "device found\n");
122 
123 	max77686->rtc = i2c_new_dummy(i2c->adapter, I2C_ADDR_RTC);
124 	i2c_set_clientdata(max77686->rtc, max77686);
125 
126 	max77686_irq_init(max77686);
127 
128 	ret = mfd_add_devices(max77686->dev, -1, max77686_devs,
129 			      ARRAY_SIZE(max77686_devs), NULL, 0, NULL);
130 	if (ret < 0) {
131 		mfd_remove_devices(max77686->dev);
132 		i2c_unregister_device(max77686->rtc);
133 	}
134 
135 	return ret;
136 }
137 
138 static int max77686_i2c_remove(struct i2c_client *i2c)
139 {
140 	struct max77686_dev *max77686 = i2c_get_clientdata(i2c);
141 
142 	mfd_remove_devices(max77686->dev);
143 	i2c_unregister_device(max77686->rtc);
144 
145 	return 0;
146 }
147 
148 static const struct i2c_device_id max77686_i2c_id[] = {
149 	{ "max77686", TYPE_MAX77686 },
150 	{ }
151 };
152 MODULE_DEVICE_TABLE(i2c, max77686_i2c_id);
153 
154 static struct i2c_driver max77686_i2c_driver = {
155 	.driver = {
156 		   .name = "max77686",
157 		   .owner = THIS_MODULE,
158 		   .of_match_table = of_match_ptr(max77686_pmic_dt_match),
159 	},
160 	.probe = max77686_i2c_probe,
161 	.remove = max77686_i2c_remove,
162 	.id_table = max77686_i2c_id,
163 };
164 
165 static int __init max77686_i2c_init(void)
166 {
167 	return i2c_add_driver(&max77686_i2c_driver);
168 }
169 /* init early so consumer devices can complete system boot */
170 subsys_initcall(max77686_i2c_init);
171 
172 static void __exit max77686_i2c_exit(void)
173 {
174 	i2c_del_driver(&max77686_i2c_driver);
175 }
176 module_exit(max77686_i2c_exit);
177 
178 MODULE_DESCRIPTION("MAXIM 77686 multi-function core driver");
179 MODULE_AUTHOR("Chiwoong Byun <woong.byun@samsung.com>");
180 MODULE_LICENSE("GPL");
181