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// Copyright 2021 The Pigweed Authors
//
// Licensed 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
//
// https://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.
#pragma once
#include <cstdint>
#include "pw_status/status.h"
namespace pw::spi {
// Configuration data used to determine how the Chip Select signal is controlled
// throughout a transaction.
// `kPerWriteRead` indicates that the chip-select signal should be
// activated/deactivated between calls to WriteRead()
enum class ChipSelectBehavior : uint8_t {
kPerWriteRead,
kPerTransaction,
};
// The ChipSelector class provides an abstract interface for controlling the
// chip-select signal associated with a specific SPI responder.
class ChipSelector {
public:
virtual ~ChipSelector() = default;
// SetActive sets the state of the chip-select signal to the value represented
// by the `active` parameter. Passing a value of `true` will activate the
// chip-select signal, and `false` will deactivate the chip-select signal.
// Returns OkStatus() on success, and implementation-specific values on
// failure.
virtual Status SetActive(bool active) = 0;
// Helper method to activate the chip-select signal
// Returns OkStatus() on success, and implementation-specific values on
// failure.
Status Activate() { return SetActive(true); }
// Helper method to deactivate the chip-select signal
// Returns OkStatus() on success, and implementation-specific values on
// failure.
Status Deactivate() { return SetActive(false); }
};
} // namespace pw::spi
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