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- /****************************************************************************
- * drivers/1wire/1wire_writeread.c
- *
- * Licensed to the Apache Software Foundation (ASF) under one or more
- * contributor license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership. The
- * ASF licenses this file to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance with the
- * License. You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
- * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
- * License for the specific language governing permissions and limitations
- * under the License.
- *
- ****************************************************************************/
- /****************************************************************************
- * Included Files
- ****************************************************************************/
- #include <nuttx/config.h>
- #include <assert.h>
- #include <nuttx/1wire/1wire.h>
- #include <nuttx/1wire/1wire_master.h>
- #include "1wire_internal.h"
- /****************************************************************************
- * Public Functions
- ****************************************************************************/
- /****************************************************************************
- * Name: 1wire_writeread
- *
- * Description:
- * Receive a block of data from 1WIRE. Each read operation will be an
- * 'atomic' operation in the sense that any other 1WIRE actions will be
- * serialized and pend until this read completes.
- *
- * Input Parameters:
- * master - Device-specific state data
- * config - Described the 1WIRE configuration
- * wbuffer - A pointer to the read-only buffer of data to be written to
- * device
- * wbuflen - The number of bytes to send from the buffer
- * rbuffer - A pointer to a buffer of data to receive the data from the
- * device
- * rbuflen - The requested number of bytes to be read
- *
- * Returned Value:
- * 0: success, <0: A negated errno
- *
- ****************************************************************************/
- int onewire_writeread(FAR struct onewire_master_s *master,
- FAR const struct onewire_config_s *config,
- FAR const uint8_t *wbuffer, int wbuflen,
- FAR uint8_t *rbuffer, int rbuflen)
- {
- int ret;
- /* Avoid calling this function from a search callback to prevent a
- * deadlock
- */
- if (master->insearch == true)
- {
- return -EAGAIN;
- }
- ret = onewire_sem_wait(master);
- if (ret < 0)
- {
- return ret;
- }
- ret = onewire_reset_select(master, config->romcode);
- if (ret < 0)
- {
- goto err_unlock;
- }
- /* Perform the transfer. */
- ret = ONEWIRE_WRITE(master->dev, wbuffer, wbuflen);
- if (ret < 0)
- {
- goto err_unlock;
- }
- ret = ONEWIRE_READ(master->dev, rbuffer, rbuflen);
- err_unlock:
- onewire_sem_post(master);
- return ret;
- }
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