xref: /openbmc/linux/drivers/mfd/da9052-i2c.c (revision 9aa2cba7)
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 #include <linux/of.h>
17 
18 #include <linux/mfd/da9052/da9052.h>
19 #include <linux/mfd/da9052/reg.h>
20 
21 
22 /* I2C safe register check */
23 static inline bool i2c_safe_reg(unsigned char reg)
24 {
25 	switch (reg) {
26 	case DA9052_STATUS_A_REG:
27 	case DA9052_STATUS_B_REG:
28 	case DA9052_STATUS_C_REG:
29 	case DA9052_STATUS_D_REG:
30 	case DA9052_ADC_RES_L_REG:
31 	case DA9052_ADC_RES_H_REG:
32 	case DA9052_VDD_RES_REG:
33 	case DA9052_ICHG_AV_REG:
34 	case DA9052_TBAT_RES_REG:
35 	case DA9052_ADCIN4_RES_REG:
36 	case DA9052_ADCIN5_RES_REG:
37 	case DA9052_ADCIN6_RES_REG:
38 	case DA9052_TJUNC_RES_REG:
39 	case DA9052_TSI_X_MSB_REG:
40 	case DA9052_TSI_Y_MSB_REG:
41 	case DA9052_TSI_LSB_REG:
42 	case DA9052_TSI_Z_MSB_REG:
43 		return true;
44 	default:
45 		return false;
46 	}
47 }
48 
49 /*
50  * There is an issue with DA9052 and DA9053_AA/BA/BB PMIC where the PMIC
51  * gets lockup up or fails to respond following a system reset.
52  * This fix is to follow any read or write with a dummy read to a safe
53  * register.
54  */
55 static int da9052_i2c_fix(struct da9052 *da9052, unsigned char reg)
56 {
57 	int val;
58 
59 	switch (da9052->chip_id) {
60 	case DA9052:
61 	case DA9053_AA:
62 	case DA9053_BA:
63 	case DA9053_BB:
64 		/* A dummy read to a safe register address. */
65 		if (!i2c_safe_reg(reg))
66 			return regmap_read(da9052->regmap,
67 					   DA9052_PARK_REGISTER,
68 					   &val);
69 		break;
70 	case DA9053_BC:
71 	default:
72 		/*
73 		 * For other chips parking of I2C register
74 		 * to a safe place is not required.
75 		 */
76 		break;
77 	}
78 
79 	return 0;
80 }
81 
82 /*
83  * According to errata item 24, multiwrite mode should be avoided
84  * in order to prevent register data corruption after power-down.
85  */
86 static int da9052_i2c_disable_multiwrite(struct da9052 *da9052)
87 {
88 	int reg_val, ret;
89 
90 	ret = regmap_read(da9052->regmap, DA9052_CONTROL_B_REG, &reg_val);
91 	if (ret < 0)
92 		return ret;
93 
94 	if (!(reg_val & DA9052_CONTROL_B_WRITEMODE)) {
95 		reg_val |= DA9052_CONTROL_B_WRITEMODE;
96 		ret = regmap_write(da9052->regmap, DA9052_CONTROL_B_REG,
97 				   reg_val);
98 		if (ret < 0)
99 			return ret;
100 	}
101 
102 	return 0;
103 }
104 
105 static const struct i2c_device_id da9052_i2c_id[] = {
106 	{"da9052", DA9052},
107 	{"da9053-aa", DA9053_AA},
108 	{"da9053-ba", DA9053_BA},
109 	{"da9053-bb", DA9053_BB},
110 	{"da9053-bc", DA9053_BC},
111 	{}
112 };
113 MODULE_DEVICE_TABLE(i2c, da9052_i2c_id);
114 
115 #ifdef CONFIG_OF
116 static const struct of_device_id dialog_dt_ids[] = {
117 	{ .compatible = "dlg,da9052", .data = &da9052_i2c_id[0] },
118 	{ .compatible = "dlg,da9053-aa", .data = &da9052_i2c_id[1] },
119 	{ .compatible = "dlg,da9053-ba", .data = &da9052_i2c_id[2] },
120 	{ .compatible = "dlg,da9053-bb", .data = &da9052_i2c_id[3] },
121 	{ .compatible = "dlg,da9053-bc", .data = &da9052_i2c_id[4] },
122 	{ /* sentinel */ }
123 };
124 #endif
125 
126 static int da9052_i2c_probe(struct i2c_client *client)
127 {
128 	const struct i2c_device_id *id = i2c_client_get_device_id(client);
129 	struct da9052 *da9052;
130 	int ret;
131 
132 	da9052 = devm_kzalloc(&client->dev, sizeof(struct da9052), GFP_KERNEL);
133 	if (!da9052)
134 		return -ENOMEM;
135 
136 	da9052->dev = &client->dev;
137 	da9052->chip_irq = client->irq;
138 	da9052->fix_io = da9052_i2c_fix;
139 
140 	i2c_set_clientdata(client, da9052);
141 
142 	da9052->regmap = devm_regmap_init_i2c(client, &da9052_regmap_config);
143 	if (IS_ERR(da9052->regmap)) {
144 		ret = PTR_ERR(da9052->regmap);
145 		dev_err(&client->dev, "Failed to allocate register map: %d\n",
146 			ret);
147 		return ret;
148 	}
149 
150 	ret = da9052_i2c_disable_multiwrite(da9052);
151 	if (ret < 0)
152 		return ret;
153 
154 #ifdef CONFIG_OF
155 	if (!id)
156 		id = of_device_get_match_data(&client->dev);
157 #endif
158 
159 	if (!id) {
160 		ret = -ENODEV;
161 		dev_err(&client->dev, "id is null.\n");
162 		return ret;
163 	}
164 
165 	return da9052_device_init(da9052, id->driver_data);
166 }
167 
168 static void da9052_i2c_remove(struct i2c_client *client)
169 {
170 	struct da9052 *da9052 = i2c_get_clientdata(client);
171 
172 	da9052_device_exit(da9052);
173 }
174 
175 static struct i2c_driver da9052_i2c_driver = {
176 	.probe = da9052_i2c_probe,
177 	.remove = da9052_i2c_remove,
178 	.id_table = da9052_i2c_id,
179 	.driver = {
180 		.name = "da9052",
181 #ifdef CONFIG_OF
182 		.of_match_table = dialog_dt_ids,
183 #endif
184 	},
185 };
186 
187 static int __init da9052_i2c_init(void)
188 {
189 	int ret;
190 
191 	ret = i2c_add_driver(&da9052_i2c_driver);
192 	if (ret != 0) {
193 		pr_err("DA9052 I2C registration failed %d\n", ret);
194 		return ret;
195 	}
196 
197 	return 0;
198 }
199 subsys_initcall(da9052_i2c_init);
200 
201 static void __exit da9052_i2c_exit(void)
202 {
203 	i2c_del_driver(&da9052_i2c_driver);
204 }
205 module_exit(da9052_i2c_exit);
206 
207 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
208 MODULE_DESCRIPTION("I2C driver for Dialog DA9052 PMIC");
209