xref: /linux/drivers/mfd/da9052-i2c.c (revision ab7826595e9ec51a51f622c5fc91e2f59440481a)
1 /*
2  * I2C access for DA9052 PMICs.
3  *
4  * Copyright(c) 2011 Dialog Semiconductor Ltd.
5  *
6  * Author: David Dajun Chen <dchen@diasemi.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  */
14 
15 #include <linux/device.h>
16 #include <linux/module.h>
17 #include <linux/input.h>
18 #include <linux/mfd/core.h>
19 #include <linux/i2c.h>
20 #include <linux/err.h>
21 
22 #include <linux/mfd/da9052/da9052.h>
23 #include <linux/mfd/da9052/reg.h>
24 
25 #ifdef CONFIG_OF
26 #include <linux/of.h>
27 #include <linux/of_device.h>
28 #endif
29 
30 /* I2C safe register check */
31 static inline bool i2c_safe_reg(unsigned char reg)
32 {
33 	switch (reg) {
34 	case DA9052_STATUS_A_REG:
35 	case DA9052_STATUS_B_REG:
36 	case DA9052_STATUS_C_REG:
37 	case DA9052_STATUS_D_REG:
38 	case DA9052_ADC_RES_L_REG:
39 	case DA9052_ADC_RES_H_REG:
40 	case DA9052_VDD_RES_REG:
41 	case DA9052_ICHG_AV_REG:
42 	case DA9052_TBAT_RES_REG:
43 	case DA9052_ADCIN4_RES_REG:
44 	case DA9052_ADCIN5_RES_REG:
45 	case DA9052_ADCIN6_RES_REG:
46 	case DA9052_TJUNC_RES_REG:
47 	case DA9052_TSI_X_MSB_REG:
48 	case DA9052_TSI_Y_MSB_REG:
49 	case DA9052_TSI_LSB_REG:
50 	case DA9052_TSI_Z_MSB_REG:
51 		return true;
52 	default:
53 		return false;
54 	}
55 }
56 
57 /*
58  * There is an issue with DA9052 and DA9053_AA/BA/BB PMIC where the PMIC
59  * gets lockup up or fails to respond following a system reset.
60  * This fix is to follow any read or write with a dummy read to a safe
61  * register.
62  */
63 static int da9052_i2c_fix(struct da9052 *da9052, unsigned char reg)
64 {
65 	int val;
66 
67 	switch (da9052->chip_id) {
68 	case DA9052:
69 	case DA9053_AA:
70 	case DA9053_BA:
71 	case DA9053_BB:
72 		/* A dummy read to a safe register address. */
73 	if (!i2c_safe_reg(reg))
74 			return regmap_read(da9052->regmap,
75 					   DA9052_PARK_REGISTER,
76 					   &val);
77 		break;
78 	default:
79 		/*
80 		 * For other chips parking of I2C register
81 		 * to a safe place is not required.
82 		 */
83 		break;
84 	}
85 
86 	return 0;
87 }
88 
89 static int da9052_i2c_enable_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 	{}
114 };
115 
116 #ifdef CONFIG_OF
117 static const struct of_device_id dialog_dt_ids[] = {
118 	{ .compatible = "dlg,da9052", .data = &da9052_i2c_id[0] },
119 	{ .compatible = "dlg,da9053-aa", .data = &da9052_i2c_id[1] },
120 	{ .compatible = "dlg,da9053-ab", .data = &da9052_i2c_id[2] },
121 	{ .compatible = "dlg,da9053-bb", .data = &da9052_i2c_id[3] },
122 	{ /* sentinel */ }
123 };
124 #endif
125 
126 static int da9052_i2c_probe(struct i2c_client *client,
127 				       const struct i2c_device_id *id)
128 {
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 	if (!i2c_check_functionality(client->adapter,
137 				     I2C_FUNC_SMBUS_BYTE_DATA)) {
138 		dev_info(&client->dev, "Error in %s:i2c_check_functionality\n",
139 			 __func__);
140 		return  -ENODEV;
141 	}
142 
143 	da9052->dev = &client->dev;
144 	da9052->chip_irq = client->irq;
145 	da9052->fix_io = da9052_i2c_fix;
146 
147 	i2c_set_clientdata(client, da9052);
148 
149 	da9052->regmap = devm_regmap_init_i2c(client, &da9052_regmap_config);
150 	if (IS_ERR(da9052->regmap)) {
151 		ret = PTR_ERR(da9052->regmap);
152 		dev_err(&client->dev, "Failed to allocate register map: %d\n",
153 			ret);
154 		return ret;
155 	}
156 
157 	ret = da9052_i2c_enable_multiwrite(da9052);
158 	if (ret < 0)
159 		return ret;
160 
161 #ifdef CONFIG_OF
162 	if (!id) {
163 		struct device_node *np = client->dev.of_node;
164 		const struct of_device_id *deviceid;
165 
166 		deviceid = of_match_node(dialog_dt_ids, np);
167 		id = deviceid->data;
168 	}
169 #endif
170 
171 	if (!id) {
172 		ret = -ENODEV;
173 		dev_err(&client->dev, "id is null.\n");
174 		return ret;
175 	}
176 
177 	ret = da9052_device_init(da9052, id->driver_data);
178 	if (ret != 0)
179 		return ret;
180 
181 	return 0;
182 }
183 
184 static int da9052_i2c_remove(struct i2c_client *client)
185 {
186 	struct da9052 *da9052 = i2c_get_clientdata(client);
187 
188 	da9052_device_exit(da9052);
189 	return 0;
190 }
191 
192 static struct i2c_driver da9052_i2c_driver = {
193 	.probe = da9052_i2c_probe,
194 	.remove = da9052_i2c_remove,
195 	.id_table = da9052_i2c_id,
196 	.driver = {
197 		.name = "da9052",
198 		.owner = THIS_MODULE,
199 #ifdef CONFIG_OF
200 		.of_match_table = dialog_dt_ids,
201 #endif
202 	},
203 };
204 
205 static int __init da9052_i2c_init(void)
206 {
207 	int ret;
208 
209 	ret = i2c_add_driver(&da9052_i2c_driver);
210 	if (ret != 0) {
211 		pr_err("DA9052 I2C registration failed %d\n", ret);
212 		return ret;
213 	}
214 
215 	return 0;
216 }
217 subsys_initcall(da9052_i2c_init);
218 
219 static void __exit da9052_i2c_exit(void)
220 {
221 	i2c_del_driver(&da9052_i2c_driver);
222 }
223 module_exit(da9052_i2c_exit);
224 
225 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
226 MODULE_DESCRIPTION("I2C driver for Dialog DA9052 PMIC");
227 MODULE_LICENSE("GPL");
228