xref: /openbmc/linux/drivers/mfd/da9052-i2c.c (revision e65e175b)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * I2C access for DA9052 PMICs.
4  *
5  * Copyright(c) 2011 Dialog Semiconductor Ltd.
6  *
7  * Author: David Dajun Chen <dchen@diasemi.com>
8  */
9 
10 #include <linux/device.h>
11 #include <linux/module.h>
12 #include <linux/input.h>
13 #include <linux/mfd/core.h>
14 #include <linux/i2c.h>
15 #include <linux/err.h>
16 
17 #include <linux/mfd/da9052/da9052.h>
18 #include <linux/mfd/da9052/reg.h>
19 
20 #ifdef CONFIG_OF
21 #include <linux/of.h>
22 #include <linux/of_device.h>
23 #endif
24 
25 /* I2C safe register check */
26 static inline bool i2c_safe_reg(unsigned char reg)
27 {
28 	switch (reg) {
29 	case DA9052_STATUS_A_REG:
30 	case DA9052_STATUS_B_REG:
31 	case DA9052_STATUS_C_REG:
32 	case DA9052_STATUS_D_REG:
33 	case DA9052_ADC_RES_L_REG:
34 	case DA9052_ADC_RES_H_REG:
35 	case DA9052_VDD_RES_REG:
36 	case DA9052_ICHG_AV_REG:
37 	case DA9052_TBAT_RES_REG:
38 	case DA9052_ADCIN4_RES_REG:
39 	case DA9052_ADCIN5_RES_REG:
40 	case DA9052_ADCIN6_RES_REG:
41 	case DA9052_TJUNC_RES_REG:
42 	case DA9052_TSI_X_MSB_REG:
43 	case DA9052_TSI_Y_MSB_REG:
44 	case DA9052_TSI_LSB_REG:
45 	case DA9052_TSI_Z_MSB_REG:
46 		return true;
47 	default:
48 		return false;
49 	}
50 }
51 
52 /*
53  * There is an issue with DA9052 and DA9053_AA/BA/BB PMIC where the PMIC
54  * gets lockup up or fails to respond following a system reset.
55  * This fix is to follow any read or write with a dummy read to a safe
56  * register.
57  */
58 static int da9052_i2c_fix(struct da9052 *da9052, unsigned char reg)
59 {
60 	int val;
61 
62 	switch (da9052->chip_id) {
63 	case DA9052:
64 	case DA9053_AA:
65 	case DA9053_BA:
66 	case DA9053_BB:
67 		/* A dummy read to a safe register address. */
68 		if (!i2c_safe_reg(reg))
69 			return regmap_read(da9052->regmap,
70 					   DA9052_PARK_REGISTER,
71 					   &val);
72 		break;
73 	case DA9053_BC:
74 	default:
75 		/*
76 		 * For other chips parking of I2C register
77 		 * to a safe place is not required.
78 		 */
79 		break;
80 	}
81 
82 	return 0;
83 }
84 
85 /*
86  * According to errata item 24, multiwrite mode should be avoided
87  * in order to prevent register data corruption after power-down.
88  */
89 static int da9052_i2c_disable_multiwrite(struct da9052 *da9052)
90 {
91 	int reg_val, ret;
92 
93 	ret = regmap_read(da9052->regmap, DA9052_CONTROL_B_REG, &reg_val);
94 	if (ret < 0)
95 		return ret;
96 
97 	if (!(reg_val & DA9052_CONTROL_B_WRITEMODE)) {
98 		reg_val |= DA9052_CONTROL_B_WRITEMODE;
99 		ret = regmap_write(da9052->regmap, DA9052_CONTROL_B_REG,
100 				   reg_val);
101 		if (ret < 0)
102 			return ret;
103 	}
104 
105 	return 0;
106 }
107 
108 static const struct i2c_device_id da9052_i2c_id[] = {
109 	{"da9052", DA9052},
110 	{"da9053-aa", DA9053_AA},
111 	{"da9053-ba", DA9053_BA},
112 	{"da9053-bb", DA9053_BB},
113 	{"da9053-bc", DA9053_BC},
114 	{}
115 };
116 MODULE_DEVICE_TABLE(i2c, da9052_i2c_id);
117 
118 #ifdef CONFIG_OF
119 static const struct of_device_id dialog_dt_ids[] = {
120 	{ .compatible = "dlg,da9052", .data = &da9052_i2c_id[0] },
121 	{ .compatible = "dlg,da9053-aa", .data = &da9052_i2c_id[1] },
122 	{ .compatible = "dlg,da9053-ba", .data = &da9052_i2c_id[2] },
123 	{ .compatible = "dlg,da9053-bb", .data = &da9052_i2c_id[3] },
124 	{ .compatible = "dlg,da9053-bc", .data = &da9052_i2c_id[4] },
125 	{ /* sentinel */ }
126 };
127 #endif
128 
129 static int da9052_i2c_probe(struct i2c_client *client)
130 {
131 	const struct i2c_device_id *id = i2c_client_get_device_id(client);
132 	struct da9052 *da9052;
133 	int ret;
134 
135 	da9052 = devm_kzalloc(&client->dev, sizeof(struct da9052), GFP_KERNEL);
136 	if (!da9052)
137 		return -ENOMEM;
138 
139 	da9052->dev = &client->dev;
140 	da9052->chip_irq = client->irq;
141 	da9052->fix_io = da9052_i2c_fix;
142 
143 	i2c_set_clientdata(client, da9052);
144 
145 	da9052->regmap = devm_regmap_init_i2c(client, &da9052_regmap_config);
146 	if (IS_ERR(da9052->regmap)) {
147 		ret = PTR_ERR(da9052->regmap);
148 		dev_err(&client->dev, "Failed to allocate register map: %d\n",
149 			ret);
150 		return ret;
151 	}
152 
153 	ret = da9052_i2c_disable_multiwrite(da9052);
154 	if (ret < 0)
155 		return ret;
156 
157 #ifdef CONFIG_OF
158 	if (!id)
159 		id = of_device_get_match_data(&client->dev);
160 #endif
161 
162 	if (!id) {
163 		ret = -ENODEV;
164 		dev_err(&client->dev, "id is null.\n");
165 		return ret;
166 	}
167 
168 	return da9052_device_init(da9052, id->driver_data);
169 }
170 
171 static void da9052_i2c_remove(struct i2c_client *client)
172 {
173 	struct da9052 *da9052 = i2c_get_clientdata(client);
174 
175 	da9052_device_exit(da9052);
176 }
177 
178 static struct i2c_driver da9052_i2c_driver = {
179 	.probe_new = da9052_i2c_probe,
180 	.remove = da9052_i2c_remove,
181 	.id_table = da9052_i2c_id,
182 	.driver = {
183 		.name = "da9052",
184 #ifdef CONFIG_OF
185 		.of_match_table = dialog_dt_ids,
186 #endif
187 	},
188 };
189 
190 static int __init da9052_i2c_init(void)
191 {
192 	int ret;
193 
194 	ret = i2c_add_driver(&da9052_i2c_driver);
195 	if (ret != 0) {
196 		pr_err("DA9052 I2C registration failed %d\n", ret);
197 		return ret;
198 	}
199 
200 	return 0;
201 }
202 subsys_initcall(da9052_i2c_init);
203 
204 static void __exit da9052_i2c_exit(void)
205 {
206 	i2c_del_driver(&da9052_i2c_driver);
207 }
208 module_exit(da9052_i2c_exit);
209 
210 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
211 MODULE_DESCRIPTION("I2C driver for Dialog DA9052 PMIC");
212 MODULE_LICENSE("GPL");
213