1 #pragma once 2 3 #include <chrono> 4 #include <string> 5 6 namespace hwmonio { 7 8 static constexpr auto retries = 10; 9 static constexpr auto delay = std::chrono::milliseconds{100}; 10 11 /** @class HwmonIO 12 * @brief Convenience wrappers for HWMON sysfs attribute IO. 13 * 14 * Unburden the rest of the application from having to check 15 * ENOENT after every hwmon attribute io operation. Hwmon 16 * device drivers can be unbound at any time; the program 17 * cannot always be terminated externally before we try to 18 * do an io. 19 */ 20 class HwmonIO 21 { 22 public: 23 HwmonIO() = delete; 24 HwmonIO(const HwmonIO&) = default; 25 HwmonIO(HwmonIO&&) = default; 26 HwmonIO& operator=(const HwmonIO&) = default; 27 HwmonIO& operator=(HwmonIO&&) = default; 28 ~HwmonIO() = default; 29 30 /** @brief Constructor 31 * 32 * @param[in] path - hwmon instance root - eg: 33 * /sys/class/hwmon/hwmon<N> 34 */ 35 explicit HwmonIO(const std::string& path); 36 37 /** @brief Perform formatted hwmon sysfs read. 38 * 39 * Propagates any exceptions other than ENOENT. 40 * ENOENT will result in a call to exit(0) in case 41 * the underlying hwmon driver is unbound and 42 * the program is inadvertently left running. 43 * 44 * For possibly transient errors will retry up to 45 * the specified number of times. 46 * 47 * @param[in] type - The hwmon type (ex. temp). 48 * @param[in] id - The hwmon id (ex. 1). 49 * @param[in] sensor - The hwmon sensor (ex. input). 50 * @param[in] retries - The number of times to retry. 51 * @param[in] delay - The time to sleep between retry attempts. 52 * 53 * @return val - The read value. 54 */ 55 int64_t read( 56 const std::string& type, 57 const std::string& id, 58 const std::string& sensor, 59 size_t retries, 60 std::chrono::milliseconds delay) const; 61 62 /** @brief Perform formatted hwmon sysfs write. 63 * 64 * Propagates any exceptions other than ENOENT. 65 * ENOENT will result in a call to exit(0) in case 66 * the underlying hwmon driver is unbound and 67 * the program is inadvertently left running. 68 * 69 * For possibly transient errors will retry up to 70 * the specified number of times. 71 * 72 * @param[in] val - The value to be written. 73 * @param[in] type - The hwmon type (ex. fan). 74 * @param[in] id - The hwmon id (ex. 1). 75 * @param[in] retries - The number of times to retry. 76 * @param[in] delay - The time to sleep between retry attempts. 77 */ 78 void write( 79 uint32_t val, 80 const std::string& type, 81 const std::string& id, 82 const std::string& sensor, 83 size_t retries, 84 std::chrono::milliseconds delay) const; 85 86 87 /** @brief Hwmon instance path access. 88 * 89 * @return path - The hwmon instance path. 90 */ 91 std::string path() const; 92 93 private: 94 std::string p; 95 }; 96 } // namespace hwmonio 97 98 // vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4 99