mfd: da9052/53 lockup fix
[~shefty/rdma-dev.git] / drivers / mfd / da9052-i2c.c
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 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 EXPORT_SYMBOL(da9052_i2c_fix);
89
90 static int da9052_i2c_enable_multiwrite(struct da9052 *da9052)
91 {
92         int reg_val, ret;
93
94         ret = regmap_read(da9052->regmap, DA9052_CONTROL_B_REG, &reg_val);
95         if (ret < 0)
96                 return ret;
97
98         if (reg_val & DA9052_CONTROL_B_WRITEMODE) {
99                 reg_val &= ~DA9052_CONTROL_B_WRITEMODE;
100                 ret = regmap_write(da9052->regmap, DA9052_CONTROL_B_REG,
101                                    reg_val);
102                 if (ret < 0)
103                         return ret;
104         }
105
106         return 0;
107 }
108
109 static const struct i2c_device_id da9052_i2c_id[] = {
110         {"da9052", DA9052},
111         {"da9053-aa", DA9053_AA},
112         {"da9053-ba", DA9053_BA},
113         {"da9053-bb", DA9053_BB},
114         {}
115 };
116
117 #ifdef CONFIG_OF
118 static const struct of_device_id dialog_dt_ids[] = {
119         { .compatible = "dlg,da9052", .data = &da9052_i2c_id[0] },
120         { .compatible = "dlg,da9053-aa", .data = &da9052_i2c_id[1] },
121         { .compatible = "dlg,da9053-ab", .data = &da9052_i2c_id[2] },
122         { .compatible = "dlg,da9053-bb", .data = &da9052_i2c_id[3] },
123         { /* sentinel */ }
124 };
125 #endif
126
127 static int da9052_i2c_probe(struct i2c_client *client,
128                                        const struct i2c_device_id *id)
129 {
130         struct da9052 *da9052;
131         int ret;
132
133         da9052 = devm_kzalloc(&client->dev, sizeof(struct da9052), GFP_KERNEL);
134         if (!da9052)
135                 return -ENOMEM;
136
137         if (!i2c_check_functionality(client->adapter,
138                                      I2C_FUNC_SMBUS_BYTE_DATA)) {
139                 dev_info(&client->dev, "Error in %s:i2c_check_functionality\n",
140                          __func__);
141                 return  -ENODEV;
142         }
143
144         da9052->dev = &client->dev;
145         da9052->chip_irq = client->irq;
146         da9052->fix_io = da9052_i2c_fix;
147
148         i2c_set_clientdata(client, da9052);
149
150         da9052->regmap = devm_regmap_init_i2c(client, &da9052_regmap_config);
151         if (IS_ERR(da9052->regmap)) {
152                 ret = PTR_ERR(da9052->regmap);
153                 dev_err(&client->dev, "Failed to allocate register map: %d\n",
154                         ret);
155                 return ret;
156         }
157
158         ret = da9052_i2c_enable_multiwrite(da9052);
159         if (ret < 0)
160                 return ret;
161
162 #ifdef CONFIG_OF
163         if (!id) {
164                 struct device_node *np = client->dev.of_node;
165                 const struct of_device_id *deviceid;
166
167                 deviceid = of_match_node(dialog_dt_ids, np);
168                 id = deviceid->data;
169         }
170 #endif
171
172         if (!id) {
173                 ret = -ENODEV;
174                 dev_err(&client->dev, "id is null.\n");
175                 return ret;
176         }
177
178         ret = da9052_device_init(da9052, id->driver_data);
179         if (ret != 0)
180                 return ret;
181
182         return 0;
183 }
184
185 static int da9052_i2c_remove(struct i2c_client *client)
186 {
187         struct da9052 *da9052 = i2c_get_clientdata(client);
188
189         da9052_device_exit(da9052);
190         return 0;
191 }
192
193 static struct i2c_driver da9052_i2c_driver = {
194         .probe = da9052_i2c_probe,
195         .remove = da9052_i2c_remove,
196         .id_table = da9052_i2c_id,
197         .driver = {
198                 .name = "da9052",
199                 .owner = THIS_MODULE,
200 #ifdef CONFIG_OF
201                 .of_match_table = dialog_dt_ids,
202 #endif
203         },
204 };
205
206 static int __init da9052_i2c_init(void)
207 {
208         int ret;
209
210         ret = i2c_add_driver(&da9052_i2c_driver);
211         if (ret != 0) {
212                 pr_err("DA9052 I2C registration failed %d\n", ret);
213                 return ret;
214         }
215
216         return 0;
217 }
218 subsys_initcall(da9052_i2c_init);
219
220 static void __exit da9052_i2c_exit(void)
221 {
222         i2c_del_driver(&da9052_i2c_driver);
223 }
224 module_exit(da9052_i2c_exit);
225
226 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
227 MODULE_DESCRIPTION("I2C driver for Dialog DA9052 PMIC");
228 MODULE_LICENSE("GPL");