1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * I2C driver for Maxim MAX8925
4 *
5 * Copyright (C) 2009 Marvell International Ltd.
6 * Haojian Zhuang <haojian.zhuang@marvell.com>
7 */
8 #include <linux/kernel.h>
9 #include <linux/init.h>
10 #include <linux/platform_device.h>
11 #include <linux/i2c.h>
12 #include <linux/mfd/max8925.h>
13 #include <linux/slab.h>
14
15 #define RTC_I2C_ADDR 0x68
16 #define ADC_I2C_ADDR 0x47
17
max8925_read_device(struct i2c_client * i2c,int reg,int bytes,void * dest)18 static inline int max8925_read_device(struct i2c_client *i2c,
19 int reg, int bytes, void *dest)
20 {
21 int ret;
22
23 if (bytes > 1)
24 ret = i2c_smbus_read_i2c_block_data(i2c, reg, bytes, dest);
25 else {
26 ret = i2c_smbus_read_byte_data(i2c, reg);
27 if (ret < 0)
28 return ret;
29 *(unsigned char *)dest = (unsigned char)ret;
30 }
31 return ret;
32 }
33
max8925_write_device(struct i2c_client * i2c,int reg,int bytes,void * src)34 static inline int max8925_write_device(struct i2c_client *i2c,
35 int reg, int bytes, void *src)
36 {
37 unsigned char buf[9];
38 int ret;
39
40 buf[0] = (unsigned char)reg;
41 memcpy(&buf[1], src, bytes);
42
43 ret = i2c_master_send(i2c, buf, bytes + 1);
44 if (ret < 0)
45 return ret;
46 return 0;
47 }
48
max8925_reg_read(struct i2c_client * i2c,int reg)49 int max8925_reg_read(struct i2c_client *i2c, int reg)
50 {
51 struct max8925_chip *chip = i2c_get_clientdata(i2c);
52 unsigned char data = 0;
53 int ret;
54
55 mutex_lock(&chip->io_lock);
56 ret = max8925_read_device(i2c, reg, 1, &data);
57 mutex_unlock(&chip->io_lock);
58
59 if (ret < 0)
60 return ret;
61 else
62 return (int)data;
63 }
64 EXPORT_SYMBOL(max8925_reg_read);
65
max8925_reg_write(struct i2c_client * i2c,int reg,unsigned char data)66 int max8925_reg_write(struct i2c_client *i2c, int reg,
67 unsigned char data)
68 {
69 struct max8925_chip *chip = i2c_get_clientdata(i2c);
70 int ret;
71
72 mutex_lock(&chip->io_lock);
73 ret = max8925_write_device(i2c, reg, 1, &data);
74 mutex_unlock(&chip->io_lock);
75
76 return ret;
77 }
78 EXPORT_SYMBOL(max8925_reg_write);
79
max8925_bulk_read(struct i2c_client * i2c,int reg,int count,unsigned char * buf)80 int max8925_bulk_read(struct i2c_client *i2c, int reg,
81 int count, unsigned char *buf)
82 {
83 struct max8925_chip *chip = i2c_get_clientdata(i2c);
84 int ret;
85
86 mutex_lock(&chip->io_lock);
87 ret = max8925_read_device(i2c, reg, count, buf);
88 mutex_unlock(&chip->io_lock);
89
90 return ret;
91 }
92 EXPORT_SYMBOL(max8925_bulk_read);
93
max8925_bulk_write(struct i2c_client * i2c,int reg,int count,unsigned char * buf)94 int max8925_bulk_write(struct i2c_client *i2c, int reg,
95 int count, unsigned char *buf)
96 {
97 struct max8925_chip *chip = i2c_get_clientdata(i2c);
98 int ret;
99
100 mutex_lock(&chip->io_lock);
101 ret = max8925_write_device(i2c, reg, count, buf);
102 mutex_unlock(&chip->io_lock);
103
104 return ret;
105 }
106 EXPORT_SYMBOL(max8925_bulk_write);
107
max8925_set_bits(struct i2c_client * i2c,int reg,unsigned char mask,unsigned char data)108 int max8925_set_bits(struct i2c_client *i2c, int reg,
109 unsigned char mask, unsigned char data)
110 {
111 struct max8925_chip *chip = i2c_get_clientdata(i2c);
112 unsigned char value;
113 int ret;
114
115 mutex_lock(&chip->io_lock);
116 ret = max8925_read_device(i2c, reg, 1, &value);
117 if (ret < 0)
118 goto out;
119 value &= ~mask;
120 value |= data;
121 ret = max8925_write_device(i2c, reg, 1, &value);
122 out:
123 mutex_unlock(&chip->io_lock);
124 return ret;
125 }
126 EXPORT_SYMBOL(max8925_set_bits);
127
128
129 static const struct i2c_device_id max8925_id_table[] = {
130 { "max8925", 0 },
131 { },
132 };
133
max8925_dt_init(struct device_node * np,struct device * dev,struct max8925_platform_data * pdata)134 static int max8925_dt_init(struct device_node *np, struct device *dev,
135 struct max8925_platform_data *pdata)
136 {
137 int ret;
138
139 ret = of_property_read_u32(np, "maxim,tsc-irq", &pdata->tsc_irq);
140 if (ret) {
141 dev_err(dev, "Not found maxim,tsc-irq property\n");
142 return -EINVAL;
143 }
144 return 0;
145 }
146
max8925_probe(struct i2c_client * client)147 static int max8925_probe(struct i2c_client *client)
148 {
149 struct max8925_platform_data *pdata = dev_get_platdata(&client->dev);
150 struct max8925_chip *chip;
151 struct device_node *node = client->dev.of_node;
152
153 if (node && !pdata) {
154 /* parse DT to get platform data */
155 pdata = devm_kzalloc(&client->dev,
156 sizeof(struct max8925_platform_data),
157 GFP_KERNEL);
158 if (!pdata)
159 return -ENOMEM;
160
161 if (max8925_dt_init(node, &client->dev, pdata))
162 return -EINVAL;
163 } else if (!pdata) {
164 pr_info("%s: platform data is missing\n", __func__);
165 return -EINVAL;
166 }
167
168 chip = devm_kzalloc(&client->dev,
169 sizeof(struct max8925_chip), GFP_KERNEL);
170 if (chip == NULL)
171 return -ENOMEM;
172 chip->i2c = client;
173 chip->dev = &client->dev;
174 i2c_set_clientdata(client, chip);
175 mutex_init(&chip->io_lock);
176
177 chip->rtc = i2c_new_dummy_device(chip->i2c->adapter, RTC_I2C_ADDR);
178 if (IS_ERR(chip->rtc)) {
179 dev_err(chip->dev, "Failed to allocate I2C device for RTC\n");
180 return PTR_ERR(chip->rtc);
181 }
182 i2c_set_clientdata(chip->rtc, chip);
183
184 chip->adc = i2c_new_dummy_device(chip->i2c->adapter, ADC_I2C_ADDR);
185 if (IS_ERR(chip->adc)) {
186 dev_err(chip->dev, "Failed to allocate I2C device for ADC\n");
187 i2c_unregister_device(chip->rtc);
188 return PTR_ERR(chip->adc);
189 }
190 i2c_set_clientdata(chip->adc, chip);
191
192 device_init_wakeup(&client->dev, 1);
193
194 max8925_device_init(chip, pdata);
195
196 return 0;
197 }
198
max8925_remove(struct i2c_client * client)199 static void max8925_remove(struct i2c_client *client)
200 {
201 struct max8925_chip *chip = i2c_get_clientdata(client);
202
203 max8925_device_exit(chip);
204 i2c_unregister_device(chip->adc);
205 i2c_unregister_device(chip->rtc);
206 }
207
max8925_suspend(struct device * dev)208 static int max8925_suspend(struct device *dev)
209 {
210 struct i2c_client *client = to_i2c_client(dev);
211 struct max8925_chip *chip = i2c_get_clientdata(client);
212
213 if (device_may_wakeup(dev) && chip->wakeup_flag)
214 enable_irq_wake(chip->core_irq);
215 return 0;
216 }
217
max8925_resume(struct device * dev)218 static int max8925_resume(struct device *dev)
219 {
220 struct i2c_client *client = to_i2c_client(dev);
221 struct max8925_chip *chip = i2c_get_clientdata(client);
222
223 if (device_may_wakeup(dev) && chip->wakeup_flag)
224 disable_irq_wake(chip->core_irq);
225 return 0;
226 }
227
228 static DEFINE_SIMPLE_DEV_PM_OPS(max8925_pm_ops,
229 max8925_suspend, max8925_resume);
230
231 static const struct of_device_id max8925_dt_ids[] = {
232 { .compatible = "maxim,max8925", },
233 {},
234 };
235
236 static struct i2c_driver max8925_driver = {
237 .driver = {
238 .name = "max8925",
239 .pm = pm_sleep_ptr(&max8925_pm_ops),
240 .of_match_table = max8925_dt_ids,
241 },
242 .probe = max8925_probe,
243 .remove = max8925_remove,
244 .id_table = max8925_id_table,
245 };
246
max8925_i2c_init(void)247 static int __init max8925_i2c_init(void)
248 {
249 int ret;
250
251 ret = i2c_add_driver(&max8925_driver);
252 if (ret != 0)
253 pr_err("Failed to register MAX8925 I2C driver: %d\n", ret);
254
255 return ret;
256 }
257 subsys_initcall(max8925_i2c_init);
258