xref: /openbmc/linux/drivers/mfd/88pm80x.c (revision 842ed298)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * I2C driver for Marvell 88PM80x
4  *
5  * Copyright (C) 2012 Marvell International Ltd.
6  * Haojian Zhuang <haojian.zhuang@marvell.com>
7  * Joseph(Yossi) Hanin <yhanin@marvell.com>
8  * Qiao Zhou <zhouqiao@marvell.com>
9  */
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/i2c.h>
13 #include <linux/mfd/88pm80x.h>
14 #include <linux/slab.h>
15 #include <linux/uaccess.h>
16 #include <linux/err.h>
17 
18 /* 88pm80x chips have same definition for chip id register. */
19 #define PM80X_CHIP_ID			(0x00)
20 #define PM80X_CHIP_ID_NUM(x)		(((x) >> 5) & 0x7)
21 #define PM80X_CHIP_ID_REVISION(x)	((x) & 0x1F)
22 
23 struct pm80x_chip_mapping {
24 	unsigned int	id;
25 	int		type;
26 };
27 
28 static struct pm80x_chip_mapping chip_mapping[] = {
29 	/* 88PM800 chip id number */
30 	{0x3,	CHIP_PM800},
31 	/* 88PM805 chip id number */
32 	{0x0,	CHIP_PM805},
33 	/* 88PM860 chip id number */
34 	{0x4,	CHIP_PM860},
35 };
36 
37 /*
38  * workaround: some registers needed by pm805 are defined in pm800, so
39  * need to use this global variable to maintain the relation between
40  * pm800 and pm805. would remove it after HW chip fixes the issue.
41  */
42 static struct pm80x_chip *g_pm80x_chip;
43 
44 const struct regmap_config pm80x_regmap_config = {
45 	.reg_bits = 8,
46 	.val_bits = 8,
47 };
48 EXPORT_SYMBOL_GPL(pm80x_regmap_config);
49 
50 
51 int pm80x_init(struct i2c_client *client)
52 {
53 	struct pm80x_chip *chip;
54 	struct regmap *map;
55 	unsigned int val;
56 	int i, ret = 0;
57 
58 	chip =
59 	    devm_kzalloc(&client->dev, sizeof(struct pm80x_chip), GFP_KERNEL);
60 	if (!chip)
61 		return -ENOMEM;
62 
63 	map = devm_regmap_init_i2c(client, &pm80x_regmap_config);
64 	if (IS_ERR(map)) {
65 		ret = PTR_ERR(map);
66 		dev_err(&client->dev, "Failed to allocate register map: %d\n",
67 			ret);
68 		return ret;
69 	}
70 
71 	chip->client = client;
72 	chip->regmap = map;
73 
74 	chip->irq = client->irq;
75 
76 	chip->dev = &client->dev;
77 	dev_set_drvdata(chip->dev, chip);
78 	i2c_set_clientdata(chip->client, chip);
79 
80 	ret = regmap_read(chip->regmap, PM80X_CHIP_ID, &val);
81 	if (ret < 0) {
82 		dev_err(chip->dev, "Failed to read CHIP ID: %d\n", ret);
83 		return ret;
84 	}
85 
86 	for (i = 0; i < ARRAY_SIZE(chip_mapping); i++) {
87 		if (chip_mapping[i].id == PM80X_CHIP_ID_NUM(val)) {
88 			chip->type = chip_mapping[i].type;
89 			break;
90 		}
91 	}
92 
93 	if (i == ARRAY_SIZE(chip_mapping)) {
94 		dev_err(chip->dev,
95 			"Failed to detect Marvell 88PM800:ChipID[0x%x]\n", val);
96 		return -EINVAL;
97 	}
98 
99 	device_init_wakeup(&client->dev, 1);
100 
101 	/*
102 	 * workaround: set g_pm80x_chip to the first probed chip. if the
103 	 * second chip is probed, just point to the companion to each
104 	 * other so that pm805 can access those specific register. would
105 	 * remove it after HW chip fixes the issue.
106 	 */
107 	if (!g_pm80x_chip)
108 		g_pm80x_chip = chip;
109 	else {
110 		chip->companion = g_pm80x_chip->client;
111 		g_pm80x_chip->companion = chip->client;
112 	}
113 
114 	return 0;
115 }
116 EXPORT_SYMBOL_GPL(pm80x_init);
117 
118 int pm80x_deinit(void)
119 {
120 	/*
121 	 * workaround: clear the dependency between pm800 and pm805.
122 	 * would remove it after HW chip fixes the issue.
123 	 */
124 	if (g_pm80x_chip->companion)
125 		g_pm80x_chip->companion = NULL;
126 	else
127 		g_pm80x_chip = NULL;
128 	return 0;
129 }
130 EXPORT_SYMBOL_GPL(pm80x_deinit);
131 
132 #ifdef CONFIG_PM_SLEEP
133 static int pm80x_suspend(struct device *dev)
134 {
135 	struct i2c_client *client = to_i2c_client(dev);
136 	struct pm80x_chip *chip = i2c_get_clientdata(client);
137 
138 	if (chip && chip->wu_flag)
139 		if (device_may_wakeup(chip->dev))
140 			enable_irq_wake(chip->irq);
141 
142 	return 0;
143 }
144 
145 static int pm80x_resume(struct device *dev)
146 {
147 	struct i2c_client *client = to_i2c_client(dev);
148 	struct pm80x_chip *chip = i2c_get_clientdata(client);
149 
150 	if (chip && chip->wu_flag)
151 		if (device_may_wakeup(chip->dev))
152 			disable_irq_wake(chip->irq);
153 
154 	return 0;
155 }
156 #endif
157 
158 SIMPLE_DEV_PM_OPS(pm80x_pm_ops, pm80x_suspend, pm80x_resume);
159 EXPORT_SYMBOL_GPL(pm80x_pm_ops);
160 
161 MODULE_DESCRIPTION("I2C Driver for Marvell 88PM80x");
162 MODULE_AUTHOR("Qiao Zhou <zhouqiao@marvell.com>");
163 MODULE_LICENSE("GPL");
164