1 /*
2 * Copyright (c) 2023 Intel Corporation
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #include <zephyr/drivers/i2c.h>
8 #include <zephyr/drivers/i2c/rtio.h>
9 #include <zephyr/rtio/rtio.h>
10 #include <zephyr/sys/mpsc_lockfree.h>
11 #include <zephyr/sys/__assert.h>
12
13 #define LOG_LEVEL CONFIG_I2C_LOG_LEVEL
14 #include <zephyr/logging/log.h>
15 LOG_MODULE_REGISTER(i2c_rtio);
16
17 const struct rtio_iodev_api i2c_iodev_api = {
18 .submit = i2c_iodev_submit,
19 };
20
i2c_rtio_copy(struct rtio * r,struct rtio_iodev * iodev,const struct i2c_msg * msgs,uint8_t num_msgs)21 struct rtio_sqe *i2c_rtio_copy(struct rtio *r, struct rtio_iodev *iodev, const struct i2c_msg *msgs,
22 uint8_t num_msgs)
23 {
24 __ASSERT(num_msgs > 0, "Expecting at least one message to copy");
25
26 struct rtio_sqe *sqe = NULL;
27
28 for (uint8_t i = 0; i < num_msgs; i++) {
29 sqe = rtio_sqe_acquire(r);
30
31 if (sqe == NULL) {
32 rtio_sqe_drop_all(r);
33 return NULL;
34 }
35
36 if (msgs[i].flags & I2C_MSG_READ) {
37 rtio_sqe_prep_read(sqe, iodev, RTIO_PRIO_NORM, msgs[i].buf, msgs[i].len,
38 NULL);
39 } else {
40 rtio_sqe_prep_write(sqe, iodev, RTIO_PRIO_NORM, msgs[i].buf, msgs[i].len,
41 NULL);
42 }
43 sqe->flags |= RTIO_SQE_TRANSACTION;
44 sqe->iodev_flags =
45 ((msgs[i].flags & I2C_MSG_STOP) ? RTIO_IODEV_I2C_STOP : 0) |
46 ((msgs[i].flags & I2C_MSG_RESTART) ? RTIO_IODEV_I2C_RESTART : 0) |
47 ((msgs[i].flags & I2C_MSG_ADDR_10_BITS) ? RTIO_IODEV_I2C_10_BITS : 0);
48 }
49
50 sqe->flags &= ~RTIO_SQE_TRANSACTION;
51
52 return sqe;
53 }
54
i2c_rtio_init(struct i2c_rtio * ctx,const struct device * dev)55 void i2c_rtio_init(struct i2c_rtio *ctx, const struct device *dev)
56 {
57 k_sem_init(&ctx->lock, 1, 1);
58 mpsc_init(&ctx->io_q);
59 ctx->txn_curr = NULL;
60 ctx->txn_head = NULL;
61 ctx->dt_spec.bus = dev;
62 ctx->iodev.data = &ctx->dt_spec;
63 ctx->iodev.api = &i2c_iodev_api;
64 }
65
66 /**
67 * @private
68 * @brief Setup the next transaction (could be a single op) if needed
69 *
70 * @retval true New transaction to start with the hardware is setup
71 * @retval false No new transaction to start
72 */
i2c_rtio_next(struct i2c_rtio * ctx,bool completion)73 static bool i2c_rtio_next(struct i2c_rtio *ctx, bool completion)
74 {
75 k_spinlock_key_t key = k_spin_lock(&ctx->slock);
76
77 /* Already working on something, bail early */
78 if (!completion && ctx->txn_head != NULL) {
79 k_spin_unlock(&ctx->slock, key);
80 return false;
81 }
82
83 struct mpsc_node *next = mpsc_pop(&ctx->io_q);
84
85 /* Nothing left to do */
86 if (next == NULL) {
87 ctx->txn_head = NULL;
88 ctx->txn_curr = NULL;
89 k_spin_unlock(&ctx->slock, key);
90 return false;
91 }
92
93 ctx->txn_head = CONTAINER_OF(next, struct rtio_iodev_sqe, q);
94 ctx->txn_curr = ctx->txn_head;
95
96 k_spin_unlock(&ctx->slock, key);
97
98 return true;
99 }
100
i2c_rtio_complete(struct i2c_rtio * ctx,int status)101 bool i2c_rtio_complete(struct i2c_rtio *ctx, int status)
102 {
103 /* On error bail */
104 if (status < 0) {
105 rtio_iodev_sqe_err(ctx->txn_head, status);
106 return i2c_rtio_next(ctx, true);
107 }
108
109 /* Try for next submission in the transaction */
110 ctx->txn_curr = rtio_txn_next(ctx->txn_curr);
111 if (ctx->txn_curr) {
112 return true;
113 }
114
115 rtio_iodev_sqe_ok(ctx->txn_head, status);
116 return i2c_rtio_next(ctx, true);
117 }
i2c_rtio_submit(struct i2c_rtio * ctx,struct rtio_iodev_sqe * iodev_sqe)118 bool i2c_rtio_submit(struct i2c_rtio *ctx, struct rtio_iodev_sqe *iodev_sqe)
119 {
120 mpsc_push(&ctx->io_q, &iodev_sqe->q);
121 return i2c_rtio_next(ctx, false);
122 }
123
i2c_rtio_transfer(struct i2c_rtio * ctx,struct i2c_msg * msgs,uint8_t num_msgs,uint16_t addr)124 int i2c_rtio_transfer(struct i2c_rtio *ctx, struct i2c_msg *msgs, uint8_t num_msgs, uint16_t addr)
125 {
126 struct rtio_iodev *iodev = &ctx->iodev;
127 struct rtio *const r = ctx->r;
128 struct rtio_sqe *sqe = NULL;
129 struct rtio_cqe *cqe = NULL;
130 int res = 0;
131
132 k_sem_take(&ctx->lock, K_FOREVER);
133
134 ctx->dt_spec.addr = addr;
135
136 sqe = i2c_rtio_copy(r, iodev, msgs, num_msgs);
137 if (sqe == NULL) {
138 LOG_ERR("Not enough submission queue entries");
139 res = -ENOMEM;
140 goto out;
141 }
142
143 rtio_submit(r, 1);
144
145 cqe = rtio_cqe_consume(r);
146 while (cqe != NULL) {
147 res = cqe->result;
148 rtio_cqe_release(r, cqe);
149 cqe = rtio_cqe_consume(r);
150 }
151
152 out:
153 k_sem_give(&ctx->lock);
154 return res;
155 }
156
i2c_rtio_configure(struct i2c_rtio * ctx,uint32_t i2c_config)157 int i2c_rtio_configure(struct i2c_rtio *ctx, uint32_t i2c_config)
158 {
159 struct rtio_iodev *iodev = &ctx->iodev;
160 struct rtio *const r = ctx->r;
161 struct rtio_sqe *sqe = NULL;
162 struct rtio_cqe *cqe = NULL;
163 int res = 0;
164
165 k_sem_take(&ctx->lock, K_FOREVER);
166
167 sqe = rtio_sqe_acquire(r);
168 if (sqe == NULL) {
169 LOG_ERR("Not enough submission queue entries");
170 res = -ENOMEM;
171 goto out;
172 }
173
174 sqe->op = RTIO_OP_I2C_CONFIGURE;
175 sqe->iodev = iodev;
176 sqe->i2c_config = i2c_config;
177
178 rtio_submit(r, 1);
179
180 cqe = rtio_cqe_consume(r);
181 res = cqe->result;
182 rtio_cqe_release(r, cqe);
183
184 out:
185 k_sem_give(&ctx->lock);
186 return res;
187 }
188
i2c_rtio_recover(struct i2c_rtio * ctx)189 int i2c_rtio_recover(struct i2c_rtio *ctx)
190 {
191 struct rtio_iodev *iodev = &ctx->iodev;
192 struct rtio *const r = ctx->r;
193 struct rtio_sqe *sqe = NULL;
194 struct rtio_cqe *cqe = NULL;
195 int res = 0;
196
197 k_sem_take(&ctx->lock, K_FOREVER);
198
199 sqe = rtio_sqe_acquire(r);
200 if (sqe == NULL) {
201 LOG_ERR("Not enough submission queue entries");
202 res = -ENOMEM;
203 goto out;
204 }
205
206 sqe->op = RTIO_OP_I2C_RECOVER;
207 sqe->iodev = iodev;
208
209 rtio_submit(r, 1);
210
211 cqe = rtio_cqe_consume(r);
212 res = cqe->result;
213 rtio_cqe_release(r, cqe);
214
215 out:
216 k_sem_give(&ctx->lock);
217 return res;
218 }
219