xref: /openbmc/linux/drivers/mfd/rn5t618.c (revision 0883c2c0)
1 /*
2  * MFD core driver for Ricoh RN5T618 PMIC
3  *
4  * Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com>
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * version 2 as published by the Free Software Foundation.
9  *
10  * You should have received a copy of the GNU General Public License
11  * along with this program. If not, see <http://www.gnu.org/licenses/>.
12  */
13 
14 #include <linux/i2c.h>
15 #include <linux/mfd/core.h>
16 #include <linux/mfd/rn5t618.h>
17 #include <linux/module.h>
18 #include <linux/regmap.h>
19 
20 static const struct mfd_cell rn5t618_cells[] = {
21 	{ .name = "rn5t618-regulator" },
22 	{ .name = "rn5t618-wdt" },
23 };
24 
25 static bool rn5t618_volatile_reg(struct device *dev, unsigned int reg)
26 {
27 	switch (reg) {
28 	case RN5T618_WATCHDOGCNT:
29 	case RN5T618_DCIRQ:
30 	case RN5T618_ILIMDATAH ... RN5T618_AIN0DATAL:
31 	case RN5T618_IR_ADC1 ... RN5T618_IR_ADC3:
32 	case RN5T618_IR_GPR:
33 	case RN5T618_IR_GPF:
34 	case RN5T618_MON_IOIN:
35 	case RN5T618_INTMON:
36 		return true;
37 	default:
38 		return false;
39 	}
40 }
41 
42 static const struct regmap_config rn5t618_regmap_config = {
43 	.reg_bits	= 8,
44 	.val_bits	= 8,
45 	.volatile_reg	= rn5t618_volatile_reg,
46 	.max_register	= RN5T618_MAX_REG,
47 	.cache_type	= REGCACHE_RBTREE,
48 };
49 
50 static struct rn5t618 *rn5t618_pm_power_off;
51 
52 static void rn5t618_power_off(void)
53 {
54 	/* disable automatic repower-on */
55 	regmap_update_bits(rn5t618_pm_power_off->regmap, RN5T618_REPCNT,
56 			   RN5T618_REPCNT_REPWRON, 0);
57 	/* start power-off sequence */
58 	regmap_update_bits(rn5t618_pm_power_off->regmap, RN5T618_SLPCNT,
59 			   RN5T618_SLPCNT_SWPWROFF, RN5T618_SLPCNT_SWPWROFF);
60 }
61 
62 static int rn5t618_i2c_probe(struct i2c_client *i2c,
63 			     const struct i2c_device_id *id)
64 {
65 	struct rn5t618 *priv;
66 	int ret;
67 
68 	priv = devm_kzalloc(&i2c->dev, sizeof(*priv), GFP_KERNEL);
69 	if (!priv)
70 		return -ENOMEM;
71 
72 	i2c_set_clientdata(i2c, priv);
73 
74 	priv->regmap = devm_regmap_init_i2c(i2c, &rn5t618_regmap_config);
75 	if (IS_ERR(priv->regmap)) {
76 		ret = PTR_ERR(priv->regmap);
77 		dev_err(&i2c->dev, "regmap init failed: %d\n", ret);
78 		return ret;
79 	}
80 
81 	ret = devm_mfd_add_devices(&i2c->dev, -1, rn5t618_cells,
82 				   ARRAY_SIZE(rn5t618_cells), NULL, 0, NULL);
83 	if (ret) {
84 		dev_err(&i2c->dev, "failed to add sub-devices: %d\n", ret);
85 		return ret;
86 	}
87 
88 	if (!pm_power_off) {
89 		rn5t618_pm_power_off = priv;
90 		pm_power_off = rn5t618_power_off;
91 	}
92 
93 	return 0;
94 }
95 
96 static int rn5t618_i2c_remove(struct i2c_client *i2c)
97 {
98 	struct rn5t618 *priv = i2c_get_clientdata(i2c);
99 
100 	if (priv == rn5t618_pm_power_off) {
101 		rn5t618_pm_power_off = NULL;
102 		pm_power_off = NULL;
103 	}
104 
105 	return 0;
106 }
107 
108 static const struct of_device_id rn5t618_of_match[] = {
109 	{ .compatible = "ricoh,rn5t618" },
110 	{ }
111 };
112 MODULE_DEVICE_TABLE(of, rn5t618_of_match);
113 
114 static const struct i2c_device_id rn5t618_i2c_id[] = {
115 	{ }
116 };
117 MODULE_DEVICE_TABLE(i2c, rn5t618_i2c_id);
118 
119 static struct i2c_driver rn5t618_i2c_driver = {
120 	.driver = {
121 		.name = "rn5t618",
122 		.of_match_table = of_match_ptr(rn5t618_of_match),
123 	},
124 	.probe = rn5t618_i2c_probe,
125 	.remove = rn5t618_i2c_remove,
126 	.id_table = rn5t618_i2c_id,
127 };
128 
129 module_i2c_driver(rn5t618_i2c_driver);
130 
131 MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>");
132 MODULE_DESCRIPTION("Ricoh RN5T618 MFD driver");
133 MODULE_LICENSE("GPL v2");
134