nuttx/1wire: Adds 1wire master interface

This implements a new master interface to handle the 1-wire transition in an
atomic sense.

Signed-off-by: Marco Krahl <ocram.lhark@gmail.com>

drivers/1wire/1wire_read.c

@@ -0,0 +1,91 @@
+/****************************************************************************
+ * drivers/1wire/1wire_read.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_read
+ *
+ * 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
+ *   buffer - A pointer to a buffer of data to receive the data from the
+ *            device
+ *   buflen - The requested number of bytes to be read
+ *
+ * Returned Value:
+ *   0: success, <0: A negated errno
+ *
+ ****************************************************************************/
+
+int onewire_read(FAR struct onewire_master_s *master,
+                 FAR const struct onewire_config_s *config,
+                 FAR uint8_t *buffer, int buflen)
+{
+  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;
+    }
+
+  /* Then perform the transfer. */
+
+  ret = ONEWIRE_READ(master->dev, buffer, buflen);
+
+err_unlock:
+  onewire_sem_post(master);
+  return ret;
+}

drivers/1wire/1wire_write.c

@@ -0,0 +1,92 @@
+/****************************************************************************
+ * drivers/1wire/1wire_write.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_write
+ *
+ * Description:
+ *   Send a block of data on 1WIRE. Each write operation will be an 'atomic'
+ *   operation in the sense that any other 1WIRE actions will be serialized
+ *   and pend until this write completes.
+ *
+ * Input Parameters:
+ *   master  - Device-specific state data
+ *   config  - Described the 1WIRE configuration
+ *   buffer - A pointer to the read-only buffer of data to be written to
+ *            device
+ *   buflen - The number of bytes to send from the buffer
+ *
+ * Returned Value:
+ *   0: success, <0: A negated errno
+ *
+ ****************************************************************************/
+
+int onewire_write(FAR struct onewire_master_s *master,
+                  FAR const struct onewire_config_s *config,
+                  FAR const uint8_t *buffer, int buflen)
+{
+  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;
+    }
+
+  /* Then perform the transfer. */
+
+  ret = ONEWIRE_WRITE(master->dev, buffer, buflen);
+
+err_unlock:
+  onewire_sem_post(master);
+  return ret;
+}

drivers/1wire/1wire_writeread.c

@@ -0,0 +1,102 @@
+/****************************************************************************
+ * 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;
+}

drivers/1wire/Make.defs

@@ -20,7 +20,7 @@
 
 ifeq ($(CONFIG_1WIRE),y)
 
-CSRCS += 1wire.c 1wire_crc.c
+CSRCS += 1wire.c 1wire_crc.c 1wire_read.c 1wire_write.c 1wire_writeread.c
 
 ifeq ($(CONFIG_1WIRE_DS28E17),y)
 CSRCS += ds28e17.c

include/nuttx/1wire/1wire_master.h

@@ -0,0 +1,203 @@
+/****************************************************************************
+ * include/nuttx/1wire/1wire_master.h
+ *
+ * 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.
+ *
+ ****************************************************************************/
+
+#ifndef __INCLUDE_NUTTX_1WIRE_1WIRE_MASTER_H
+#define __INCLUDE_NUTTX_1WIRE_1WIRE_MASTER_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <stdint.h>
+#include <stdbool.h>
+
+/****************************************************************************
+ * Public Types
+ ****************************************************************************/
+
+struct onewire_dev_s;
+struct onewire_master_s;
+
+struct onewire_config_s
+{
+  uint8_t  family;                  /* Device family identifier */
+  uint64_t romcode;                 /* Unique device identifier */
+};
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: onewire_write
+ *
+ * Description:
+ *   Send a block of data on 1WIRE. Each write operation will be an 'atomic'
+ *   operation in the sense that any other 1WIRE actions will be serialized
+ *   and pend until this write completes.
+ *
+ * Input Parameters:
+ *   master - Device-specific state data
+ *   config - Described the 1WIRE configuration
+ *   buffer - A pointer to the read-only buffer of data to be written to
+ *            device
+ *   buflen - The number of bytes to send from the buffer
+ *
+ * Returned Value:
+ *   0: success, <0: A negated errno
+ *
+ ****************************************************************************/
+
+int onewire_write(FAR struct onewire_master_s *master,
+                  FAR const struct onewire_config_s *config,
+                  FAR const uint8_t *buffer, int buflen);
+
+/****************************************************************************
+ * Name: onewire_read
+ *
+ * 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
+ *   buffer - A pointer to a buffer of data to receive the data from the
+ *            device
+ *   buflen - The requested number of bytes to be read
+ *
+ * Returned Value:
+ *   0: success, <0: A negated errno
+ *
+ ****************************************************************************/
+
+int onewire_read(FAR struct onewire_master_s *master,
+                 FAR const struct onewire_config_s *config,
+                 FAR uint8_t *buffer, int buflen);
+
+/****************************************************************************
+ * Name: onewire_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);
+
+/****************************************************************************
+ * Name: onewire_search
+ *
+ * Description:
+ *   Search all devices from a 1-wire network. This is the 1-wire search
+ *   algorithm from Maxim Application Note 187. Note! This is an atomic
+ *   operation. The callback 'cb_search' can't execute any function that will
+ *   lock this bus, because of the locked state as long the search is active.
+ *
+ * Input Parameters:
+ *   master    - Pointer to the allocated 1-wire interface
+ *   family    - Limit search to devices of matching family
+ *   alarmonly - Limit search to devices on alarm state
+ *   cb_search - Callback to call on each device found
+ *   arg       - Argument passed to cb_search
+ *
+ * Return Value:
+ *   Number of slaves present and matching family.
+ *
+ ****************************************************************************/
+
+int onewire_search(FAR struct onewire_master_s *master,
+                   int family,
+                   bool alarmonly,
+                   CODE void (*cb_search)(int family,
+                                          uint64_t romcode,
+                                          FAR void *arg),
+                   FAR void *arg);
+
+/****************************************************************************
+ * Name: onewire_isalarm
+ *
+ * Description:
+ *   Check if a 1wire devices has set the alarm flag in an atomic operation.
+ *
+ * Input Parameters:
+ *   master  - Pointer to the allocated 1-wire interface
+ *   config  - Described the 1WIRE configuration
+ *
+ * Return Value:
+ *   0   - no alarm flag is set
+ *   1   - alaram flag is set
+ *   < 0 - in case of error
+ *
+ ****************************************************************************/
+
+int onewire_isalarm(FAR struct onewire_master_s *master,
+                    FAR const struct onewire_config_s *config);
+
+/****************************************************************************
+ * Name: onewire_initialize
+ *
+ * Description:
+ *   Return 1-wire bus master from 1-wire lower half device.
+ *
+ * Input Parameters:
+ *   dev       - Pointer to the allocated 1-wire lower half
+ *   maxslaves - Maximum number of 1-wire slave devices
+ *
+ ****************************************************************************/
+
+FAR struct onewire_master_s *
+onewire_initialize(FAR struct onewire_dev_s *dev, int maxslaves);
+
+/****************************************************************************
+ * Name: onewire_uninitialize
+ *
+ * Description:
+ *   Release 1-wire bus master.
+ *
+ * Input Parameters:
+ *   master    - Pointer to the allocated 1-wire master
+ *
+ ****************************************************************************/
+
+int onewire_uninitialize(FAR struct onewire_master_s *master);
+
+#endif /* __INCLUDE_NUTTX_1WIRE_1WIRE_MASTER_H */