1 /*
2 * Copyright (c) 2023 Caspar Friedrich <c.s.w.friedrich@gmail.com>
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #include "w1_ds2482-800.h"
8 #include "w1_ds2482_84_common.h"
9
10 #include <zephyr/devicetree.h>
11 #include <zephyr/drivers/i2c.h>
12 #include <zephyr/drivers/w1.h>
13 #include <zephyr/logging/log.h>
14
15 #define DT_DRV_COMPAT maxim_ds2482_800_channel
16
17 LOG_MODULE_DECLARE(ds2482, CONFIG_W1_LOG_LEVEL);
18
19 struct ds2482_config {
20 struct w1_master_config w1_config;
21 const struct device *parent;
22 const struct i2c_dt_spec i2c_spec;
23 uint8_t reg_channel;
24 uint8_t reg_channel_rb;
25 uint8_t reg_config;
26 };
27
28 struct ds2482_data {
29 struct w1_master_data w1_data;
30 };
31
ds2482_reset_bus(const struct device * dev)32 static int ds2482_reset_bus(const struct device *dev)
33 {
34 const struct ds2482_config *config = dev->config;
35
36 return ds2482_84_reset_bus(&config->i2c_spec);
37 }
38
ds2482_read_bit(const struct device * dev)39 static int ds2482_read_bit(const struct device *dev)
40 {
41 const struct ds2482_config *config = dev->config;
42
43 return ds2482_84_read_bit(&config->i2c_spec);
44 }
45
ds2482_write_bit(const struct device * dev,bool bit)46 static int ds2482_write_bit(const struct device *dev, bool bit)
47 {
48 const struct ds2482_config *config = dev->config;
49
50 return ds2482_84_write_bit(&config->i2c_spec, bit);
51 }
52
ds2482_read_byte(const struct device * dev)53 static int ds2482_read_byte(const struct device *dev)
54 {
55 const struct ds2482_config *config = dev->config;
56
57 return ds2482_84_read_byte(&config->i2c_spec);
58 }
59
ds2482_write_byte(const struct device * dev,uint8_t byte)60 static int ds2482_write_byte(const struct device *dev, uint8_t byte)
61 {
62 const struct ds2482_config *config = dev->config;
63
64 return ds2482_84_write_byte(&config->i2c_spec, byte);
65 }
66
ds2482_configure(const struct device * dev,enum w1_settings_type type,uint32_t value)67 static int ds2482_configure(const struct device *dev, enum w1_settings_type type, uint32_t value)
68 {
69 const struct ds2482_config *config = dev->config;
70
71 uint8_t reg_config = config->reg_config;
72
73 switch (type) {
74 case W1_SETTING_SPEED:
75 WRITE_BIT(reg_config, DEVICE_1WS_pos, value);
76 break;
77 case W1_SETTING_STRONG_PULLUP:
78 WRITE_BIT(reg_config, DEVICE_SPU_pos, value);
79 break;
80 default:
81 return -EINVAL;
82 }
83
84 return ds2482_84_write_config(&config->i2c_spec, reg_config);
85 }
86
ds2482_set_channel(const struct i2c_dt_spec * spec,uint8_t channel,uint8_t channel_rb)87 static int ds2482_set_channel(const struct i2c_dt_spec *spec, uint8_t channel, uint8_t channel_rb)
88 {
89 int ret;
90
91 uint8_t reg = channel;
92
93 ret = ds2482_84_write(spec, CMD_CHSL, ®);
94 if (ret < 0) {
95 return ret;
96 }
97
98 ret = ds2482_84_read(spec, REG_NONE, ®);
99 if (ret < 0) {
100 return ret;
101 }
102
103 return (reg == channel_rb) ? 0 : -EIO;
104 }
105
ds2482_change_bus_lock(const struct device * dev,bool lock)106 static int ds2482_change_bus_lock(const struct device *dev, bool lock)
107 {
108 int ret;
109
110 const struct ds2482_config *config = dev->config;
111
112 ret = ds2482_change_bus_lock_impl(config->parent, lock);
113 if (ret < 0) {
114 LOG_ERR("Failed to acquire bus lock: %d", ret);
115 return ret;
116 }
117
118 if (!lock) {
119 return 0;
120 }
121
122 /*
123 * Set channel for subsequent operations
124 */
125 ret = ds2482_set_channel(&config->i2c_spec, config->reg_channel, config->reg_channel_rb);
126 if (ret < 0) {
127 return ret;
128 }
129
130 /*
131 * Restore default channel configuration
132 */
133 ret = ds2482_84_write_config(&config->i2c_spec, config->reg_config);
134 if (ret < 0) {
135 return ret;
136 }
137
138 return 0;
139 }
140
ds2482_init(const struct device * dev)141 static int ds2482_init(const struct device *dev)
142 {
143 const struct ds2482_config *config = dev->config;
144
145 if (!device_is_ready(config->parent)) {
146 return -ENODEV;
147 }
148
149 return 0;
150 }
151
152 static DEVICE_API(w1, ds2482_driver_api) = {
153 .reset_bus = ds2482_reset_bus,
154 .read_bit = ds2482_read_bit,
155 .write_bit = ds2482_write_bit,
156 .read_byte = ds2482_read_byte,
157 .write_byte = ds2482_write_byte,
158 .configure = ds2482_configure,
159 .change_bus_lock = ds2482_change_bus_lock,
160 };
161
162 #define DS2482_CHANNEL_INIT(inst) \
163 static const struct ds2482_config inst_##inst##_config = { \
164 .w1_config.slave_count = W1_INST_SLAVE_COUNT(inst), \
165 .parent = DEVICE_DT_GET(DT_INST_PARENT(inst)), \
166 .i2c_spec = I2C_DT_SPEC_GET(DT_INST_PARENT(inst)), \
167 .reg_channel = UTIL_CAT(CHSL_IO, DT_INST_REG_ADDR_RAW(inst)), \
168 .reg_channel_rb = UTIL_CAT(CHSL_RB_IO, DT_INST_REG_ADDR_RAW(inst)), \
169 .reg_config = DT_INST_PROP(inst, active_pullup) << DEVICE_APU_pos, \
170 }; \
171 static struct ds2482_data inst_##inst##_data = {0}; \
172 DEVICE_DT_INST_DEFINE(inst, ds2482_init, NULL, &inst_##inst##_data, &inst_##inst##_config, \
173 POST_KERNEL, CONFIG_W1_INIT_PRIORITY, &ds2482_driver_api);
174
175 DT_INST_FOREACH_STATUS_OKAY(DS2482_CHANNEL_INIT)
176
177 /*
178 * Make sure that this driver is not initialized before the i2c bus is available
179 */
180 BUILD_ASSERT(CONFIG_W1_INIT_PRIORITY > CONFIG_I2C_INIT_PRIORITY);
181
