1 /*
2 * Copyright (c) 2018, Nordic Semiconductor ASA
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7
8 #include <zephyr/drivers/i2c.h>
9 #include <zephyr/dt-bindings/i2c/i2c.h>
10 #include <zephyr/pm/device.h>
11 #include <zephyr/drivers/pinctrl.h>
12 #include <soc.h>
13 #include <nrfx_twi.h>
14 #include "i2c_nrfx_twi_common.h"
15
16 #include <zephyr/logging/log.h>
17 #include <zephyr/irq.h>
18 LOG_MODULE_REGISTER(i2c_nrfx_twi, CONFIG_I2C_LOG_LEVEL);
19
20 #if CONFIG_I2C_NRFX_TRANSFER_TIMEOUT
21 #define I2C_TRANSFER_TIMEOUT_MSEC K_MSEC(CONFIG_I2C_NRFX_TRANSFER_TIMEOUT)
22 #else
23 #define I2C_TRANSFER_TIMEOUT_MSEC K_FOREVER
24 #endif
25
26 struct i2c_nrfx_twi_data {
27 uint32_t dev_config;
28 struct k_sem transfer_sync;
29 struct k_sem completion_sync;
30 volatile nrfx_err_t res;
31 };
32
33 /* Enforce dev_config matches the same offset as the common structure,
34 * otherwise common API won't be compatible with i2c_nrfx_twi.
35 */
36 BUILD_ASSERT(
37 offsetof(struct i2c_nrfx_twi_data, dev_config) ==
38 offsetof(struct i2c_nrfx_twi_common_data, dev_config)
39 );
40
i2c_nrfx_twi_transfer(const struct device * dev,struct i2c_msg * msgs,uint8_t num_msgs,uint16_t addr)41 static int i2c_nrfx_twi_transfer(const struct device *dev,
42 struct i2c_msg *msgs,
43 uint8_t num_msgs, uint16_t addr)
44 {
45 const struct i2c_nrfx_twi_config *config = dev->config;
46 struct i2c_nrfx_twi_data *data = dev->data;
47 int ret = 0;
48
49 k_sem_take(&data->transfer_sync, K_FOREVER);
50
51 /* Dummy take on completion_sync sem to be sure that it is empty */
52 k_sem_take(&data->completion_sync, K_NO_WAIT);
53
54 nrfx_twi_enable(&config->twi);
55
56 for (size_t i = 0; i < num_msgs; i++) {
57 bool more_msgs = ((i < (num_msgs - 1)) &&
58 !(msgs[i + 1].flags & I2C_MSG_RESTART));
59
60 ret = i2c_nrfx_twi_msg_transfer(dev, msgs[i].flags,
61 msgs[i].buf,
62 msgs[i].len, addr,
63 more_msgs);
64 if (ret) {
65 break;
66 }
67
68 ret = k_sem_take(&data->completion_sync,
69 I2C_TRANSFER_TIMEOUT_MSEC);
70 if (ret != 0) {
71 /* Whatever the frequency, completion_sync should have
72 * been given by the event handler.
73 *
74 * If it hasn't, it's probably due to an hardware issue
75 * on the I2C line, for example a short between SDA and
76 * GND.
77 * This is issue has also been when trying to use the
78 * I2C bus during MCU internal flash erase.
79 *
80 * In many situation, a retry is sufficient.
81 * However, some time the I2C device get stuck and need
82 * help to recover.
83 * Therefore we always call i2c_nrfx_twi_recover_bus()
84 * to make sure everything has been done to restore the
85 * bus from this error.
86 */
87 nrfx_twi_disable(&config->twi);
88 (void)i2c_nrfx_twi_recover_bus(dev);
89 ret = -EIO;
90 break;
91 }
92
93 if (data->res != NRFX_SUCCESS) {
94 ret = -EIO;
95 break;
96 }
97 }
98
99 nrfx_twi_disable(&config->twi);
100 k_sem_give(&data->transfer_sync);
101
102 return ret;
103 }
104
event_handler(nrfx_twi_evt_t const * p_event,void * p_context)105 static void event_handler(nrfx_twi_evt_t const *p_event, void *p_context)
106 {
107 const struct device *dev = p_context;
108 struct i2c_nrfx_twi_data *dev_data = (struct i2c_nrfx_twi_data *)dev->data;
109
110 switch (p_event->type) {
111 case NRFX_TWI_EVT_DONE:
112 dev_data->res = NRFX_SUCCESS;
113 break;
114 case NRFX_TWI_EVT_ADDRESS_NACK:
115 dev_data->res = NRFX_ERROR_DRV_TWI_ERR_ANACK;
116 break;
117 case NRFX_TWI_EVT_DATA_NACK:
118 dev_data->res = NRFX_ERROR_DRV_TWI_ERR_DNACK;
119 break;
120 default:
121 dev_data->res = NRFX_ERROR_INTERNAL;
122 break;
123 }
124
125 k_sem_give(&dev_data->completion_sync);
126 }
127
128 static DEVICE_API(i2c, i2c_nrfx_twi_driver_api) = {
129 .configure = i2c_nrfx_twi_configure,
130 .transfer = i2c_nrfx_twi_transfer,
131 .recover_bus = i2c_nrfx_twi_recover_bus,
132 };
133
134 #define I2C_NRFX_TWI_DEVICE(idx) \
135 NRF_DT_CHECK_NODE_HAS_PINCTRL_SLEEP(I2C(idx)); \
136 BUILD_ASSERT(I2C_FREQUENCY(idx) != \
137 I2C_NRFX_TWI_INVALID_FREQUENCY, \
138 "Wrong I2C " #idx " frequency setting in dts"); \
139 static int twi_##idx##_init(const struct device *dev) \
140 { \
141 IRQ_CONNECT(DT_IRQN(I2C(idx)), DT_IRQ(I2C(idx), priority), \
142 nrfx_isr, nrfx_twi_##idx##_irq_handler, 0); \
143 const struct i2c_nrfx_twi_config *config = dev->config; \
144 int err = pinctrl_apply_state(config->pcfg, \
145 PINCTRL_STATE_DEFAULT); \
146 if (err < 0) { \
147 return err; \
148 } \
149 return i2c_nrfx_twi_init(dev); \
150 } \
151 static struct i2c_nrfx_twi_data twi_##idx##_data = { \
152 .transfer_sync = Z_SEM_INITIALIZER( \
153 twi_##idx##_data.transfer_sync, 1, 1), \
154 .completion_sync = Z_SEM_INITIALIZER( \
155 twi_##idx##_data.completion_sync, 0, 1) \
156 }; \
157 PINCTRL_DT_DEFINE(I2C(idx)); \
158 static const struct i2c_nrfx_twi_config twi_##idx##z_config = { \
159 .twi = NRFX_TWI_INSTANCE(idx), \
160 .config = { \
161 .skip_gpio_cfg = true, \
162 .skip_psel_cfg = true, \
163 .frequency = I2C_FREQUENCY(idx), \
164 }, \
165 .event_handler = event_handler, \
166 .pcfg = PINCTRL_DT_DEV_CONFIG_GET(I2C(idx)), \
167 }; \
168 PM_DEVICE_DT_DEFINE(I2C(idx), twi_nrfx_pm_action); \
169 I2C_DEVICE_DT_DEFINE(I2C(idx), \
170 twi_##idx##_init, \
171 PM_DEVICE_DT_GET(I2C(idx)), \
172 &twi_##idx##_data, \
173 &twi_##idx##z_config, \
174 POST_KERNEL, \
175 CONFIG_I2C_INIT_PRIORITY, \
176 &i2c_nrfx_twi_driver_api)
177
178 #ifdef CONFIG_HAS_HW_NRF_TWI0
179 I2C_NRFX_TWI_DEVICE(0);
180 #endif
181
182 #ifdef CONFIG_HAS_HW_NRF_TWI1
183 I2C_NRFX_TWI_DEVICE(1);
184 #endif
185
