blob: b86f9ba35fb2b2c9511a4e6820cd2354a5773573 [file] [log] [blame]
/* spi.c - SPI based Bluetooth driver */
#define DT_DRV_COMPAT zephyr_bt_hci_spi
/*
* Copyright (c) 2017 Linaro Ltd.
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <zephyr/drivers/gpio.h>
#include <zephyr/init.h>
#include <zephyr/drivers/spi.h>
#include <zephyr/sys/byteorder.h>
#include <zephyr/sys/util.h>
#include <zephyr/bluetooth/hci.h>
#include <zephyr/drivers/bluetooth/hci_driver.h>
#define LOG_LEVEL CONFIG_BT_HCI_DRIVER_LOG_LEVEL
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(bt_driver);
#define HCI_CMD 0x01
#define HCI_ACL 0x02
#define HCI_SCO 0x03
#define HCI_EVT 0x04
/* Special Values */
#define SPI_WRITE 0x0A
#define SPI_READ 0x0B
#define READY_NOW 0x02
#define EVT_BLUE_INITIALIZED 0x01
/* Offsets */
#define STATUS_HEADER_READY 0
#define STATUS_HEADER_TOREAD 3
#define PACKET_TYPE 0
#define EVT_HEADER_TYPE 0
#define EVT_HEADER_EVENT 1
#define EVT_HEADER_SIZE 2
#define EVT_VENDOR_CODE_LSB 3
#define EVT_VENDOR_CODE_MSB 4
#define CMD_OGF 1
#define CMD_OCF 2
/* Max SPI buffer length for transceive operations.
*
* Buffer size needs to be at least the size of the larger RX/TX buffer
* required by the SPI slave, as the legacy spi_transceive requires both RX/TX
* to be the same length. Size also needs to be compatible with the
* slave device used (e.g. nRF5X max buffer length for SPIS is 255).
*/
#define SPI_MAX_MSG_LEN 255 /* As defined by X-NUCLEO-IDB04A1 BSP */
#define DATA_DELAY_US DT_INST_PROP(0, controller_data_delay_us)
/* Single byte header denoting the buffer type */
#define H4_HDR_SIZE 1
/* Maximum L2CAP MTU that can fit in a single packet */
#define MAX_MTU (SPI_MAX_MSG_LEN - H4_HDR_SIZE - BT_L2CAP_HDR_SIZE - BT_HCI_ACL_HDR_SIZE)
#if CONFIG_BT_L2CAP_TX_MTU > MAX_MTU
#warning CONFIG_BT_L2CAP_TX_MTU is too large and can result in packets that cannot \
be transmitted across this HCI link
#endif /* CONFIG_BT_L2CAP_TX_MTU > MAX_MTU */
static uint8_t rxmsg[SPI_MAX_MSG_LEN];
static uint8_t txmsg[SPI_MAX_MSG_LEN];
static const struct gpio_dt_spec irq_gpio = GPIO_DT_SPEC_INST_GET(0, irq_gpios);
static const struct gpio_dt_spec rst_gpio = GPIO_DT_SPEC_INST_GET(0, reset_gpios);
static struct gpio_callback gpio_cb;
static K_SEM_DEFINE(sem_initialised, 0, 1);
static K_SEM_DEFINE(sem_request, 0, 1);
static K_SEM_DEFINE(sem_busy, 1, 1);
static K_KERNEL_STACK_DEFINE(spi_rx_stack, CONFIG_BT_DRV_RX_STACK_SIZE);
static struct k_thread spi_rx_thread_data;
#if defined(CONFIG_BT_HCI_DRIVER_LOG_LEVEL_DBG)
#include <zephyr/sys/printk.h>
static inline void spi_dump_message(const uint8_t *pre, uint8_t *buf,
uint8_t size)
{
uint8_t i, c;
printk("%s (%d): ", pre, size);
for (i = 0U; i < size; i++) {
c = buf[i];
printk("%x ", c);
if (c >= 31U && c <= 126U) {
printk("[%c] ", c);
} else {
printk("[.] ");
}
}
printk("\n");
}
#else
static inline
void spi_dump_message(const uint8_t *pre, uint8_t *buf, uint8_t size) {}
#endif
#if defined(CONFIG_BT_SPI_BLUENRG)
/* Define a limit when reading IRQ high */
/* It can be required to be increased for */
/* some particular cases. */
#define IRQ_HIGH_MAX_READ 3
static uint8_t attempts;
#endif /* CONFIG_BT_SPI_BLUENRG */
#if defined(CONFIG_BT_BLUENRG_ACI)
#define BLUENRG_ACI_WRITE_CONFIG_DATA BT_OP(BT_OGF_VS, 0x000C)
#define BLUENRG_ACI_WRITE_CONFIG_CMD_LL 0x2C
#define BLUENRG_ACI_LL_MODE 0x01
struct bluenrg_aci_cmd_ll_param {
uint8_t cmd;
uint8_t length;
uint8_t value;
};
static int bt_spi_send_aci_config_data_controller_mode(void);
#endif /* CONFIG_BT_BLUENRG_ACI */
#if defined(CONFIG_BT_SPI_BLUENRG)
/* In case of BlueNRG-MS, it is necessary to prevent SPI driver to release CS,
* and instead, let current driver manage CS release. see kick_cs()/release_cs()
* So, add SPI_HOLD_ON_CS to operation field.
*/
static const struct spi_dt_spec bus = SPI_DT_SPEC_INST_GET(
0, SPI_OP_MODE_MASTER | SPI_TRANSFER_MSB | SPI_WORD_SET(8) | SPI_HOLD_ON_CS, 0);
#else
static const struct spi_dt_spec bus = SPI_DT_SPEC_INST_GET(
0, SPI_OP_MODE_MASTER | SPI_TRANSFER_MSB | SPI_WORD_SET(8), 0);
#endif
static struct spi_buf spi_tx_buf;
static struct spi_buf spi_rx_buf;
static const struct spi_buf_set spi_tx = {
.buffers = &spi_tx_buf,
.count = 1
};
static const struct spi_buf_set spi_rx = {
.buffers = &spi_rx_buf,
.count = 1
};
static inline int bt_spi_transceive(void *tx, uint32_t tx_len,
void *rx, uint32_t rx_len)
{
spi_tx_buf.buf = tx;
spi_tx_buf.len = (size_t)tx_len;
spi_rx_buf.buf = rx;
spi_rx_buf.len = (size_t)rx_len;
return spi_transceive_dt(&bus, &spi_tx, &spi_rx);
}
static inline uint16_t bt_spi_get_cmd(uint8_t *msg)
{
return (msg[CMD_OCF] << 8) | msg[CMD_OGF];
}
static inline uint16_t bt_spi_get_evt(uint8_t *msg)
{
return (msg[EVT_VENDOR_CODE_MSB] << 8) | msg[EVT_VENDOR_CODE_LSB];
}
static void bt_spi_isr(const struct device *unused1,
struct gpio_callback *unused2,
uint32_t unused3)
{
LOG_DBG("");
k_sem_give(&sem_request);
}
static bool bt_spi_handle_vendor_evt(uint8_t *msg)
{
bool handled = false;
switch (bt_spi_get_evt(msg)) {
case EVT_BLUE_INITIALIZED:
k_sem_give(&sem_initialised);
#if defined(CONFIG_BT_BLUENRG_ACI)
/* force BlueNRG to be on controller mode */
bt_spi_send_aci_config_data_controller_mode();
#endif
handled = true;
default:
break;
}
return handled;
}
#if defined(CONFIG_BT_SPI_BLUENRG)
/* BlueNRG has a particuliar way to wake up from sleep and be ready.
* All is done through its CS line:
* If it is in sleep mode, the first transaction will not return ready
* status. At this point, it's necessary to release the CS and retry
* within 2ms the same transaction. And again when it's required to
* know the amount of byte to read.
* (See section 5.2 of BlueNRG-MS datasheet)
*/
static int configure_cs(void)
{
/* Configure pin as output and set to inactive */
return gpio_pin_configure_dt(&bus.config.cs.gpio, GPIO_OUTPUT_INACTIVE);
}
static void kick_cs(void)
{
gpio_pin_set_dt(&bus.config.cs.gpio, 0);
gpio_pin_set_dt(&bus.config.cs.gpio, 1);
}
static void release_cs(void)
{
gpio_pin_set_dt(&bus.config.cs.gpio, 0);
}
static bool irq_pin_high(void)
{
int pin_state;
pin_state = gpio_pin_get_dt(&irq_gpio);
LOG_DBG("IRQ Pin: %d", pin_state);
return pin_state > 0;
}
static void init_irq_high_loop(void)
{
attempts = IRQ_HIGH_MAX_READ;
}
static bool exit_irq_high_loop(void)
{
/* Limit attempts on BlueNRG-MS as we might */
/* enter this loop with nothing to read */
attempts--;
return attempts;
}
#else
#define configure_cs(...) 0
#define kick_cs(...)
#define release_cs(...)
#define irq_pin_high(...) 0
#define init_irq_high_loop(...)
#define exit_irq_high_loop(...) 1
#endif /* CONFIG_BT_SPI_BLUENRG */
#if defined(CONFIG_BT_BLUENRG_ACI)
static int bt_spi_send_aci_config_data_controller_mode(void)
{
struct bluenrg_aci_cmd_ll_param *param;
struct net_buf *buf;
buf = bt_hci_cmd_create(BLUENRG_ACI_WRITE_CONFIG_DATA, sizeof(*param));
if (!buf) {
return -ENOBUFS;
}
param = net_buf_add(buf, sizeof(*param));
param->cmd = BLUENRG_ACI_WRITE_CONFIG_CMD_LL;
param->length = 0x1;
/* Force BlueNRG-MS roles to Link Layer only mode */
param->value = BLUENRG_ACI_LL_MODE;
bt_hci_cmd_send(BLUENRG_ACI_WRITE_CONFIG_DATA, buf);
return 0;
}
#endif /* CONFIG_BT_BLUENRG_ACI */
static void bt_spi_rx_thread(void)
{
bool discardable = false;
k_timeout_t timeout = K_FOREVER;
struct net_buf *buf;
uint8_t header_master[5] = { SPI_READ, 0x00, 0x00, 0x00, 0x00 };
uint8_t header_slave[5];
struct bt_hci_acl_hdr acl_hdr;
uint8_t size = 0U;
int ret;
int len;
(void)memset(&txmsg, 0xFF, SPI_MAX_MSG_LEN);
while (true) {
/* Wait for interrupt pin to be active */
k_sem_take(&sem_request, K_FOREVER);
LOG_DBG("");
do {
/* Wait for SPI bus to be available */
k_sem_take(&sem_busy, K_FOREVER);
init_irq_high_loop();
do {
kick_cs();
ret = bt_spi_transceive(header_master, 5,
header_slave, 5);
} while ((((header_slave[STATUS_HEADER_TOREAD] == 0U ||
header_slave[STATUS_HEADER_TOREAD] == 0xFF) &&
!ret)) && exit_irq_high_loop());
/* Delay here is rounded up to next tick */
k_sleep(K_USEC(DATA_DELAY_US));
size = header_slave[STATUS_HEADER_TOREAD];
if (ret == 0 && size != 0) {
do {
ret = bt_spi_transceive(&txmsg, size,
&rxmsg, size);
if (rxmsg[0] == 0U) {
/* Consider increasing controller-data-delay-us
* if this message is extremely common.
*/
LOG_DBG("Controller not ready for SPI transaction "
"of %d bytes", size);
}
} while (rxmsg[0] == 0U && ret == 0);
}
release_cs();
k_sem_give(&sem_busy);
if (ret || size == 0) {
if (ret) {
LOG_ERR("Error %d", ret);
}
continue;
}
spi_dump_message("RX:ed", rxmsg, size);
switch (rxmsg[PACKET_TYPE]) {
case HCI_EVT:
switch (rxmsg[EVT_HEADER_EVENT]) {
case BT_HCI_EVT_VENDOR:
/* Run event through interface handler */
if (bt_spi_handle_vendor_evt(rxmsg)) {
continue;
};
/* Event has not yet been handled */
__fallthrough;
default:
if (rxmsg[1] == BT_HCI_EVT_LE_META_EVENT &&
(rxmsg[3] == BT_HCI_EVT_LE_ADVERTISING_REPORT)) {
discardable = true;
timeout = K_NO_WAIT;
}
buf = bt_buf_get_evt(rxmsg[EVT_HEADER_EVENT],
discardable, timeout);
if (!buf) {
LOG_DBG("Discard adv report due to insufficient "
"buf");
continue;
}
}
len = sizeof(struct bt_hci_evt_hdr) + rxmsg[EVT_HEADER_SIZE];
if (len > net_buf_tailroom(buf)) {
LOG_ERR("Event too long: %d", len);
net_buf_unref(buf);
continue;
}
net_buf_add_mem(buf, &rxmsg[1], len);
break;
case HCI_ACL:
buf = bt_buf_get_rx(BT_BUF_ACL_IN, K_FOREVER);
memcpy(&acl_hdr, &rxmsg[1], sizeof(acl_hdr));
len = sizeof(acl_hdr) + sys_le16_to_cpu(acl_hdr.len);
if (len > net_buf_tailroom(buf)) {
LOG_ERR("ACL too long: %d", len);
net_buf_unref(buf);
continue;
}
net_buf_add_mem(buf, &rxmsg[1], len);
break;
default:
LOG_ERR("Unknown BT buf type %d", rxmsg[0]);
continue;
}
bt_recv(buf);
/* On BlueNRG-MS, host is expected to read */
/* as long as IRQ pin is high */
} while (irq_pin_high());
}
}
static int bt_spi_send(struct net_buf *buf)
{
uint8_t header[5] = { SPI_WRITE, 0x00, 0x00, 0x00, 0x00 };
int ret;
LOG_DBG("");
/* Buffer needs an additional byte for type */
if (buf->len >= SPI_MAX_MSG_LEN) {
LOG_ERR("Message too long (%d)", buf->len);
return -EINVAL;
}
/* Wait for SPI bus to be available */
k_sem_take(&sem_busy, K_FOREVER);
switch (bt_buf_get_type(buf)) {
case BT_BUF_ACL_OUT:
net_buf_push_u8(buf, HCI_ACL);
break;
case BT_BUF_CMD:
net_buf_push_u8(buf, HCI_CMD);
break;
default:
LOG_ERR("Unsupported type");
k_sem_give(&sem_busy);
return -EINVAL;
}
/* Poll sanity values until device has woken-up */
do {
kick_cs();
ret = bt_spi_transceive(header, 5, rxmsg, 5);
/*
* RX Header (rxmsg) must contain a sanity check Byte and size
* information. If it does not contain BOTH then it is
* sleeping or still in the initialisation stage (waking-up).
*/
} while ((rxmsg[STATUS_HEADER_READY] != READY_NOW ||
(rxmsg[1] | rxmsg[2] | rxmsg[3] | rxmsg[4]) == 0U) && !ret);
if (!ret) {
/* Transmit the message */
do {
ret = bt_spi_transceive(buf->data, buf->len,
rxmsg, buf->len);
} while (rxmsg[0] == 0U && !ret);
}
release_cs();
k_sem_give(&sem_busy);
if (ret) {
LOG_ERR("Error %d", ret);
goto out;
}
spi_dump_message("TX:ed", buf->data, buf->len);
#if defined(CONFIG_BT_SPI_BLUENRG)
/*
* Since a RESET has been requested, the chip will now restart.
* Unfortunately the BlueNRG will reply with "reset received" but
* since it does not send back a NOP, we have no way to tell when the
* RESET has actually taken place. Instead, we use the vendor command
* EVT_BLUE_INITIALIZED as an indication that it is safe to proceed.
*/
if (bt_spi_get_cmd(buf->data) == BT_HCI_OP_RESET) {
k_sem_take(&sem_initialised, K_FOREVER);
}
#endif /* CONFIG_BT_SPI_BLUENRG */
out:
net_buf_unref(buf);
return ret;
}
static int bt_spi_open(void)
{
int err;
/* Configure RST pin and hold BLE in Reset */
err = gpio_pin_configure_dt(&rst_gpio, GPIO_OUTPUT_ACTIVE);
if (err) {
return err;
}
/* Configure IRQ pin and the IRQ call-back/handler */
err = gpio_pin_configure_dt(&irq_gpio, GPIO_INPUT);
if (err) {
return err;
}
gpio_init_callback(&gpio_cb, bt_spi_isr, BIT(irq_gpio.pin));
err = gpio_add_callback(irq_gpio.port, &gpio_cb);
if (err) {
return err;
}
/* Enable the interrupt line */
gpio_pin_interrupt_configure_dt(&irq_gpio, GPIO_INT_EDGE_TO_ACTIVE);
/* Take BLE out of reset */
k_sleep(K_MSEC(DT_INST_PROP_OR(0, reset_assert_duration_ms, 0)));
gpio_pin_set_dt(&rst_gpio, 0);
/* Start RX thread */
k_thread_create(&spi_rx_thread_data, spi_rx_stack,
K_KERNEL_STACK_SIZEOF(spi_rx_stack),
(k_thread_entry_t)bt_spi_rx_thread, NULL, NULL, NULL,
K_PRIO_COOP(CONFIG_BT_DRIVER_RX_HIGH_PRIO),
0, K_NO_WAIT);
/* Device will let us know when it's ready */
k_sem_take(&sem_initialised, K_FOREVER);
return 0;
}
static const struct bt_hci_driver drv = {
.name = DEVICE_DT_NAME(DT_DRV_INST(0)),
.bus = BT_HCI_DRIVER_BUS_SPI,
#if defined(CONFIG_BT_BLUENRG_ACI)
.quirks = BT_QUIRK_NO_RESET,
#endif /* CONFIG_BT_BLUENRG_ACI */
.open = bt_spi_open,
.send = bt_spi_send,
};
static int bt_spi_init(void)
{
if (!spi_is_ready_dt(&bus)) {
LOG_ERR("SPI device not ready");
return -ENODEV;
}
if (configure_cs()) {
return -EIO;
}
if (!gpio_is_ready_dt(&irq_gpio)) {
LOG_ERR("IRQ GPIO device not ready");
return -ENODEV;
}
if (!gpio_is_ready_dt(&rst_gpio)) {
LOG_ERR("Reset GPIO device not ready");
return -ENODEV;
}
bt_hci_driver_register(&drv);
LOG_DBG("BT SPI initialized");
return 0;
}
SYS_INIT(bt_spi_init, POST_KERNEL, CONFIG_BT_SPI_INIT_PRIORITY);