xref: /openbmc/linux/drivers/mfd/88pm80x.c (revision 6d99a79c)
1 /*
2  * I2C driver for Marvell 88PM80x
3  *
4  * Copyright (C) 2012 Marvell International Ltd.
5  * Haojian Zhuang <haojian.zhuang@marvell.com>
6  * Joseph(Yossi) Hanin <yhanin@marvell.com>
7  * Qiao Zhou <zhouqiao@marvell.com>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  */
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/i2c.h>
16 #include <linux/mfd/88pm80x.h>
17 #include <linux/slab.h>
18 #include <linux/uaccess.h>
19 #include <linux/err.h>
20 
21 /* 88pm80x chips have same definition for chip id register. */
22 #define PM80X_CHIP_ID			(0x00)
23 #define PM80X_CHIP_ID_NUM(x)		(((x) >> 5) & 0x7)
24 #define PM80X_CHIP_ID_REVISION(x)	((x) & 0x1F)
25 
26 struct pm80x_chip_mapping {
27 	unsigned int	id;
28 	int		type;
29 };
30 
31 static struct pm80x_chip_mapping chip_mapping[] = {
32 	/* 88PM800 chip id number */
33 	{0x3,	CHIP_PM800},
34 	/* 88PM805 chip id number */
35 	{0x0,	CHIP_PM805},
36 	/* 88PM860 chip id number */
37 	{0x4,	CHIP_PM860},
38 };
39 
40 /*
41  * workaround: some registers needed by pm805 are defined in pm800, so
42  * need to use this global variable to maintain the relation between
43  * pm800 and pm805. would remove it after HW chip fixes the issue.
44  */
45 static struct pm80x_chip *g_pm80x_chip;
46 
47 const struct regmap_config pm80x_regmap_config = {
48 	.reg_bits = 8,
49 	.val_bits = 8,
50 };
51 EXPORT_SYMBOL_GPL(pm80x_regmap_config);
52 
53 
54 int pm80x_init(struct i2c_client *client)
55 {
56 	struct pm80x_chip *chip;
57 	struct regmap *map;
58 	unsigned int val;
59 	int i, ret = 0;
60 
61 	chip =
62 	    devm_kzalloc(&client->dev, sizeof(struct pm80x_chip), GFP_KERNEL);
63 	if (!chip)
64 		return -ENOMEM;
65 
66 	map = devm_regmap_init_i2c(client, &pm80x_regmap_config);
67 	if (IS_ERR(map)) {
68 		ret = PTR_ERR(map);
69 		dev_err(&client->dev, "Failed to allocate register map: %d\n",
70 			ret);
71 		return ret;
72 	}
73 
74 	chip->client = client;
75 	chip->regmap = map;
76 
77 	chip->irq = client->irq;
78 
79 	chip->dev = &client->dev;
80 	dev_set_drvdata(chip->dev, chip);
81 	i2c_set_clientdata(chip->client, chip);
82 
83 	ret = regmap_read(chip->regmap, PM80X_CHIP_ID, &val);
84 	if (ret < 0) {
85 		dev_err(chip->dev, "Failed to read CHIP ID: %d\n", ret);
86 		return ret;
87 	}
88 
89 	for (i = 0; i < ARRAY_SIZE(chip_mapping); i++) {
90 		if (chip_mapping[i].id == PM80X_CHIP_ID_NUM(val)) {
91 			chip->type = chip_mapping[i].type;
92 			break;
93 		}
94 	}
95 
96 	if (i == ARRAY_SIZE(chip_mapping)) {
97 		dev_err(chip->dev,
98 			"Failed to detect Marvell 88PM800:ChipID[0x%x]\n", val);
99 		return -EINVAL;
100 	}
101 
102 	device_init_wakeup(&client->dev, 1);
103 
104 	/*
105 	 * workaround: set g_pm80x_chip to the first probed chip. if the
106 	 * second chip is probed, just point to the companion to each
107 	 * other so that pm805 can access those specific register. would
108 	 * remove it after HW chip fixes the issue.
109 	 */
110 	if (!g_pm80x_chip)
111 		g_pm80x_chip = chip;
112 	else {
113 		chip->companion = g_pm80x_chip->client;
114 		g_pm80x_chip->companion = chip->client;
115 	}
116 
117 	return 0;
118 }
119 EXPORT_SYMBOL_GPL(pm80x_init);
120 
121 int pm80x_deinit(void)
122 {
123 	/*
124 	 * workaround: clear the dependency between pm800 and pm805.
125 	 * would remove it after HW chip fixes the issue.
126 	 */
127 	if (g_pm80x_chip->companion)
128 		g_pm80x_chip->companion = NULL;
129 	else
130 		g_pm80x_chip = NULL;
131 	return 0;
132 }
133 EXPORT_SYMBOL_GPL(pm80x_deinit);
134 
135 #ifdef CONFIG_PM_SLEEP
136 static int pm80x_suspend(struct device *dev)
137 {
138 	struct i2c_client *client = to_i2c_client(dev);
139 	struct pm80x_chip *chip = i2c_get_clientdata(client);
140 
141 	if (chip && chip->wu_flag)
142 		if (device_may_wakeup(chip->dev))
143 			enable_irq_wake(chip->irq);
144 
145 	return 0;
146 }
147 
148 static int pm80x_resume(struct device *dev)
149 {
150 	struct i2c_client *client = to_i2c_client(dev);
151 	struct pm80x_chip *chip = i2c_get_clientdata(client);
152 
153 	if (chip && chip->wu_flag)
154 		if (device_may_wakeup(chip->dev))
155 			disable_irq_wake(chip->irq);
156 
157 	return 0;
158 }
159 #endif
160 
161 SIMPLE_DEV_PM_OPS(pm80x_pm_ops, pm80x_suspend, pm80x_resume);
162 EXPORT_SYMBOL_GPL(pm80x_pm_ops);
163 
164 MODULE_DESCRIPTION("I2C Driver for Marvell 88PM80x");
165 MODULE_AUTHOR("Qiao Zhou <zhouqiao@marvell.com>");
166 MODULE_LICENSE("GPL");
167