xref: /openbmc/linux/drivers/mfd/88pm80x.c (revision 588b48ca)
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 };
37 
38 /*
39  * workaround: some registers needed by pm805 are defined in pm800, so
40  * need to use this global variable to maintain the relation between
41  * pm800 and pm805. would remove it after HW chip fixes the issue.
42  */
43 static struct pm80x_chip *g_pm80x_chip;
44 
45 const struct regmap_config pm80x_regmap_config = {
46 	.reg_bits = 8,
47 	.val_bits = 8,
48 };
49 EXPORT_SYMBOL_GPL(pm80x_regmap_config);
50 
51 
52 int pm80x_init(struct i2c_client *client)
53 {
54 	struct pm80x_chip *chip;
55 	struct regmap *map;
56 	unsigned int val;
57 	int i, ret = 0;
58 
59 	chip =
60 	    devm_kzalloc(&client->dev, sizeof(struct pm80x_chip), GFP_KERNEL);
61 	if (!chip)
62 		return -ENOMEM;
63 
64 	map = devm_regmap_init_i2c(client, &pm80x_regmap_config);
65 	if (IS_ERR(map)) {
66 		ret = PTR_ERR(map);
67 		dev_err(&client->dev, "Failed to allocate register map: %d\n",
68 			ret);
69 		return ret;
70 	}
71 
72 	chip->client = client;
73 	chip->regmap = map;
74 
75 	chip->irq = client->irq;
76 
77 	chip->dev = &client->dev;
78 	dev_set_drvdata(chip->dev, chip);
79 	i2c_set_clientdata(chip->client, chip);
80 
81 	ret = regmap_read(chip->regmap, PM80X_CHIP_ID, &val);
82 	if (ret < 0) {
83 		dev_err(chip->dev, "Failed to read CHIP ID: %d\n", ret);
84 		return ret;
85 	}
86 
87 	for (i = 0; i < ARRAY_SIZE(chip_mapping); i++) {
88 		if (chip_mapping[i].id == PM80X_CHIP_ID_NUM(val)) {
89 			chip->type = chip_mapping[i].type;
90 			break;
91 		}
92 	}
93 
94 	if (i == ARRAY_SIZE(chip_mapping)) {
95 		dev_err(chip->dev,
96 			"Failed to detect Marvell 88PM800:ChipID[0x%x]\n", val);
97 		return -EINVAL;
98 	}
99 
100 	device_init_wakeup(&client->dev, 1);
101 
102 	/*
103 	 * workaround: set g_pm80x_chip to the first probed chip. if the
104 	 * second chip is probed, just point to the companion to each
105 	 * other so that pm805 can access those specific register. would
106 	 * remove it after HW chip fixes the issue.
107 	 */
108 	if (!g_pm80x_chip)
109 		g_pm80x_chip = chip;
110 	else {
111 		chip->companion = g_pm80x_chip->client;
112 		g_pm80x_chip->companion = chip->client;
113 	}
114 
115 	return 0;
116 }
117 EXPORT_SYMBOL_GPL(pm80x_init);
118 
119 int pm80x_deinit(void)
120 {
121 	/*
122 	 * workaround: clear the dependency between pm800 and pm805.
123 	 * would remove it after HW chip fixes the issue.
124 	 */
125 	if (g_pm80x_chip->companion)
126 		g_pm80x_chip->companion = NULL;
127 	else
128 		g_pm80x_chip = NULL;
129 	return 0;
130 }
131 EXPORT_SYMBOL_GPL(pm80x_deinit);
132 
133 #ifdef CONFIG_PM_SLEEP
134 static int pm80x_suspend(struct device *dev)
135 {
136 	struct i2c_client *client = container_of(dev, struct i2c_client, dev);
137 	struct pm80x_chip *chip = i2c_get_clientdata(client);
138 
139 	if (chip && chip->wu_flag)
140 		if (device_may_wakeup(chip->dev))
141 			enable_irq_wake(chip->irq);
142 
143 	return 0;
144 }
145 
146 static int pm80x_resume(struct device *dev)
147 {
148 	struct i2c_client *client = container_of(dev, struct i2c_client, dev);
149 	struct pm80x_chip *chip = i2c_get_clientdata(client);
150 
151 	if (chip && chip->wu_flag)
152 		if (device_may_wakeup(chip->dev))
153 			disable_irq_wake(chip->irq);
154 
155 	return 0;
156 }
157 #endif
158 
159 SIMPLE_DEV_PM_OPS(pm80x_pm_ops, pm80x_suspend, pm80x_resume);
160 EXPORT_SYMBOL_GPL(pm80x_pm_ops);
161 
162 MODULE_DESCRIPTION("I2C Driver for Marvell 88PM80x");
163 MODULE_AUTHOR("Qiao Zhou <zhouqiao@marvell.com>");
164 MODULE_LICENSE("GPL");
165