Shawn McCarney | 88d5b69 | 2020-02-25 10:39:02 -0600 | [diff] [blame] | 1 | /** |
| 2 | * Copyright © 2020 IBM Corporation |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | #pragma once |
| 17 | |
| 18 | #include "action_environment.hpp" |
| 19 | #include "i2c_action.hpp" |
| 20 | |
| 21 | #include <cstdint> |
| 22 | #include <stdexcept> |
| 23 | #include <string> |
| 24 | |
| 25 | namespace phosphor::power::regulators |
| 26 | { |
| 27 | |
| 28 | /** |
| 29 | * @class I2CWriteBitAction |
| 30 | * |
| 31 | * Writes a bit to a device register. Communicates with the device directly |
| 32 | * using the I2C interface. |
| 33 | * |
| 34 | * Implements the i2c_write_bit action in the JSON config file. |
| 35 | */ |
| 36 | class I2CWriteBitAction : public I2CAction |
| 37 | { |
| 38 | public: |
| 39 | // Specify which compiler-generated methods we want |
| 40 | I2CWriteBitAction() = delete; |
| 41 | I2CWriteBitAction(const I2CWriteBitAction&) = delete; |
| 42 | I2CWriteBitAction(I2CWriteBitAction&&) = delete; |
| 43 | I2CWriteBitAction& operator=(const I2CWriteBitAction&) = delete; |
| 44 | I2CWriteBitAction& operator=(I2CWriteBitAction&&) = delete; |
| 45 | virtual ~I2CWriteBitAction() = default; |
| 46 | |
| 47 | /** |
| 48 | * Constructor. |
| 49 | * |
| 50 | * Throws an exception if any of the input parameters are invalid. |
| 51 | * |
| 52 | * @param reg Device register address. Note: named 'reg' because 'register' |
| 53 | * is a reserved keyword. |
| 54 | * @param position Bit position. Must be in the range 0-7. Bit 0 is the |
| 55 | * least significant bit. |
| 56 | * @param value Bit value to write. Must be 0 or 1. |
| 57 | */ |
| 58 | explicit I2CWriteBitAction(uint8_t reg, uint8_t position, uint8_t value) : |
| 59 | reg{reg}, position{position}, value{value} |
| 60 | { |
| 61 | if (position > 7) |
| 62 | { |
| 63 | throw std::invalid_argument{ |
| 64 | "Invalid bit position: " + |
| 65 | std::to_string(static_cast<unsigned>(position))}; |
| 66 | } |
| 67 | |
| 68 | if (value > 1) |
| 69 | { |
| 70 | throw std::invalid_argument{ |
| 71 | "Invalid bit value: " + |
| 72 | std::to_string(static_cast<unsigned>(value))}; |
| 73 | } |
| 74 | } |
| 75 | |
| 76 | /** |
| 77 | * Executes this action. |
| 78 | * |
| 79 | * Writes a bit to a device register using the I2C interface. |
| 80 | * |
| 81 | * The device register, bit position, and bit value were specified in the |
| 82 | * constructor. |
| 83 | * |
| 84 | * The device is obtained from the specified action environment. |
| 85 | * |
| 86 | * Throws an exception if an error occurs. |
| 87 | * |
| 88 | * @param environment action execution environment |
| 89 | * @return true |
| 90 | */ |
| 91 | virtual bool execute(ActionEnvironment& environment) override; |
| 92 | |
| 93 | /** |
| 94 | * Returns the device register address. |
| 95 | * |
| 96 | * @return register address |
| 97 | */ |
| 98 | uint8_t getRegister() const |
| 99 | { |
| 100 | return reg; |
| 101 | } |
| 102 | |
| 103 | /** |
| 104 | * Returns the bit position. |
| 105 | * |
| 106 | * Value is in the range 0-7. Bit 0 is the least significant bit. |
| 107 | * |
| 108 | * @return bit position |
| 109 | */ |
| 110 | uint8_t getPosition() const |
| 111 | { |
| 112 | return position; |
| 113 | } |
| 114 | |
| 115 | /** |
| 116 | * Returns the bit value to write. |
| 117 | * |
| 118 | * Value is 0 or 1. |
| 119 | * |
| 120 | * @return bit value |
| 121 | */ |
| 122 | uint8_t getValue() const |
| 123 | { |
| 124 | return value; |
| 125 | } |
| 126 | |
| 127 | /** |
| 128 | * Returns a string description of this action. |
| 129 | * |
| 130 | * @return description of action |
| 131 | */ |
| 132 | virtual std::string toString() const override; |
| 133 | |
| 134 | private: |
| 135 | /** |
| 136 | * Device register address. Note: named 'reg' because 'register' is a |
| 137 | * reserved keyword. |
| 138 | */ |
| 139 | const uint8_t reg{0x00}; |
| 140 | |
| 141 | /** |
| 142 | * Bit position. Must be in the range 0-7. Bit 0 is the least significant |
| 143 | * bit. |
| 144 | */ |
| 145 | const uint8_t position{0}; |
| 146 | |
| 147 | /** |
| 148 | * Bit value to write. Must be 0 or 1. |
| 149 | */ |
| 150 | const uint8_t value{0}; |
| 151 | }; |
| 152 | |
| 153 | } // namespace phosphor::power::regulators |