regulators: Implement i2c_compare_bytes action
Implement the i2c_compare_bytes action in the JSON config file. See
i2c_compare_bytes.md for more information about this action.
Signed-off-by: Shawn McCarney <shawnmm@us.ibm.com>
Change-Id: I6997f647a2b899f08f06de43aba62d32f88e1911
diff --git a/phosphor-regulators/src/actions/i2c_compare_bytes_action.hpp b/phosphor-regulators/src/actions/i2c_compare_bytes_action.hpp
new file mode 100644
index 0000000..3f0ec83
--- /dev/null
+++ b/phosphor-regulators/src/actions/i2c_compare_bytes_action.hpp
@@ -0,0 +1,183 @@
+/**
+ * Copyright © 2020 IBM Corporation
+ *
+ * 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
+ *
+ * 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.
+ */
+#pragma once
+
+#include "action_environment.hpp"
+#include "i2c_action.hpp"
+
+#include <cstdint>
+#include <stdexcept>
+#include <string>
+#include <vector>
+
+namespace phosphor::power::regulators
+{
+
+/**
+ * @class I2CCompareBytesAction
+ *
+ * Compares device register bytes to a list of expected values. Communicates
+ * with the device directly using the I2C interface.
+ *
+ * Implements the i2c_compare_bytes action in the JSON config file.
+ */
+class I2CCompareBytesAction : public I2CAction
+{
+ public:
+ // Specify which compiler-generated methods we want
+ I2CCompareBytesAction() = delete;
+ I2CCompareBytesAction(const I2CCompareBytesAction&) = delete;
+ I2CCompareBytesAction(I2CCompareBytesAction&&) = delete;
+ I2CCompareBytesAction& operator=(const I2CCompareBytesAction&) = delete;
+ I2CCompareBytesAction& operator=(I2CCompareBytesAction&&) = delete;
+ virtual ~I2CCompareBytesAction() = default;
+
+ /**
+ * Constructor.
+ *
+ * Throws an exception if any of the input parameters are invalid.
+ *
+ * @param reg Device register address. Note: named 'reg' because 'register'
+ * is a reserved keyword.
+ * @param values One or more expected byte values. The bytes must be
+ * specified in the same order as they will be received from
+ * the device (e.g. in little-endian order).
+ */
+ explicit I2CCompareBytesAction(uint8_t reg,
+ const std::vector<uint8_t>& values) :
+ I2CCompareBytesAction(reg, values,
+ std::vector<uint8_t>(values.size(), 0xFF))
+ {
+ }
+
+ /**
+ * Constructor.
+ *
+ * Throws an exception if any of the input parameters are invalid.
+ *
+ * @param reg Device register address. Note: named 'reg' because 'register'
+ * is a reserved keyword.
+ * @param values One or more expected byte values. The bytes must be
+ * specified in the same order as they will be received from
+ * the device (e.g. in little-endian order).
+ * @param masks One or more bit masks. The number of bit masks must match
+ * the number of expected byte values. Each mask specifies
+ * which bits should be compared within the corresponding byte
+ * value. Only the bits with a value of 1 in the mask will be
+ * compared.
+ */
+ explicit I2CCompareBytesAction(uint8_t reg,
+ const std::vector<uint8_t>& values,
+ const std::vector<uint8_t>& masks) :
+ reg{reg},
+ values{values}, masks{masks}
+ {
+ // Values vector must not be empty
+ if (values.size() < 1)
+ {
+ throw std::invalid_argument{"Values vector is empty"};
+ }
+
+ // Masks vector must have same size as values vector
+ if (masks.size() != values.size())
+ {
+ throw std::invalid_argument{"Masks vector has invalid size"};
+ }
+ }
+
+ /**
+ * Executes this action.
+ *
+ * Compares device register bytes to a list of expected values using the
+ * I2C interface.
+ *
+ * All of the bytes will be read in a single I2C operation.
+ *
+ * The device register, byte values, and bit masks (if any) were specified
+ * in the constructor.
+ *
+ * The device is obtained from the specified action environment.
+ *
+ * Throws an exception if an error occurs.
+ *
+ * @param environment action execution environment
+ * @return true if the register bytes contained the expected values,
+ * otherwise returns false.
+ */
+ virtual bool execute(ActionEnvironment& environment) override;
+
+ /**
+ * Returns the device register address.
+ *
+ * @return register address
+ */
+ uint8_t getRegister() const
+ {
+ return reg;
+ }
+
+ /**
+ * Returns the expected byte values.
+ *
+ * @return expected values
+ */
+ const std::vector<uint8_t>& getValues() const
+ {
+ return values;
+ }
+
+ /**
+ * Returns the bit masks.
+ *
+ * Each mask specifies which bits should be compared within the
+ * corresponding byte value. Only the bits with a value of 1 in the mask
+ * will be compared.
+ *
+ * @return bit masks
+ */
+ const std::vector<uint8_t>& getMasks() const
+ {
+ return masks;
+ }
+
+ /**
+ * Returns a string description of this action.
+ *
+ * @return description of action
+ */
+ virtual std::string toString() const override;
+
+ private:
+ /**
+ * Device register address. Note: named 'reg' because 'register' is a
+ * reserved keyword.
+ */
+ const uint8_t reg{0x00};
+
+ /**
+ * Expected byte values.
+ */
+ const std::vector<uint8_t> values{};
+
+ /**
+ * Bit masks. Each mask specifies which bits should be compared within the
+ * corresponding byte value. Only the bits with a value of 1 in the mask
+ * will be compared.
+ */
+ const std::vector<uint8_t> masks{};
+};
+
+} // namespace phosphor::power::regulators