zephyr/drivers/smbus/smbus_utils.c

44 lines
1.2 KiB
C

/*
* Copyright (c) 2022 Intel Corporation
* Copyright (c) 2023 SILA Embedded Solutions GmbH
* SPDX-License-Identifier: Apache-2.0
*/
#include "smbus_utils.h"
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(smbus_utils, CONFIG_SMBUS_LOG_LEVEL);
void smbus_loop_alert_devices(const struct device *dev, sys_slist_t *callbacks)
{
int result;
uint8_t address;
/**
* There might be several peripheral devices which could have triggered the alert and
* the one with the highest priority (lowest address) device wins the arbitration. In
* any case, we will have to loop through all of them.
*
* The format of the transaction is:
*
* 0 1 2
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* |S| Alert Addr |R|A| Address |X|N|P|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
while (true) {
result = smbus_byte_read(dev, SMBUS_ADDRESS_ARA, &address);
if (result != 0) {
LOG_DBG("%s: no more peripheral devices left which triggered an alert",
dev->name);
return;
}
LOG_DBG("%s: address 0x%02X triggered an alert", dev->name, address);
smbus_fire_callbacks(callbacks, dev, address);
}
}