From a4931f5d788d24bfeeefb13fb3ead037cb5eaa6e Mon Sep 17 00:00:00 2001
From: Oxan van Leeuwen <oxan@oxanvanleeuwen.nl>
Date: Thu, 6 Jan 2022 12:54:58 +0100
Subject: [PATCH] Clean-up reverse_bits helpers (#3011)

---
 .../components/remote_base/midea_protocol.cpp |  4 ++--
 esphome/components/ttp229_lsf/ttp229_lsf.cpp  |  2 +-
 esphome/core/helpers.cpp                      | 15 -------------
 esphome/core/helpers.h                        | 21 +++++++++++++++----
 4 files changed, 20 insertions(+), 22 deletions(-)

diff --git a/esphome/components/remote_base/midea_protocol.cpp b/esphome/components/remote_base/midea_protocol.cpp
index baf64f246f..a19a5b50c1 100644
--- a/esphome/components/remote_base/midea_protocol.cpp
+++ b/esphome/components/remote_base/midea_protocol.cpp
@@ -9,8 +9,8 @@ static const char *const TAG = "remote.midea";
 uint8_t MideaData::calc_cs_() const {
   uint8_t cs = 0;
   for (const uint8_t *it = this->data(); it != this->data() + OFFSET_CS; ++it)
-    cs -= reverse_bits_8(*it);
-  return reverse_bits_8(cs);
+    cs -= reverse_bits(*it);
+  return reverse_bits(cs);
 }
 
 bool MideaData::check_compliment(const MideaData &rhs) const {
diff --git a/esphome/components/ttp229_lsf/ttp229_lsf.cpp b/esphome/components/ttp229_lsf/ttp229_lsf.cpp
index 21c7b02740..773d51b76e 100644
--- a/esphome/components/ttp229_lsf/ttp229_lsf.cpp
+++ b/esphome/components/ttp229_lsf/ttp229_lsf.cpp
@@ -35,7 +35,7 @@ void TTP229LSFComponent::loop() {
   }
   touched = i2c::i2ctohs(touched);
   this->status_clear_warning();
-  touched = reverse_bits_16(touched);
+  touched = reverse_bits(touched);
   for (auto *channel : this->channels_) {
     channel->process(touched);
   }
diff --git a/esphome/core/helpers.cpp b/esphome/core/helpers.cpp
index da5d0915c2..c70aa2d6dd 100644
--- a/esphome/core/helpers.cpp
+++ b/esphome/core/helpers.cpp
@@ -187,17 +187,6 @@ void delay_microseconds_safe(uint32_t us) {  // avoids CPU locks that could trig
     ;
 }
 
-uint8_t reverse_bits_8(uint8_t x) {
-  x = ((x & 0xAA) >> 1) | ((x & 0x55) << 1);
-  x = ((x & 0xCC) >> 2) | ((x & 0x33) << 2);
-  x = ((x & 0xF0) >> 4) | ((x & 0x0F) << 4);
-  return x;
-}
-
-uint16_t reverse_bits_16(uint16_t x) {
-  return uint16_t(reverse_bits_8(x & 0xFF) << 8) | uint16_t(reverse_bits_8(x >> 8));
-}
-
 uint32_t fnv1_hash(const std::string &str) {
   uint32_t hash = 2166136261UL;
   for (char c : str) {
@@ -210,10 +199,6 @@ bool str_equals_case_insensitive(const std::string &a, const std::string &b) {
   return strcasecmp(a.c_str(), b.c_str()) == 0;
 }
 
-template<uint32_t> uint32_t reverse_bits(uint32_t x) {
-  return uint32_t(reverse_bits_16(x & 0xFFFF) << 16) | uint32_t(reverse_bits_16(x >> 16));
-}
-
 static int high_freq_num_requests = 0;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
 
 void HighFrequencyLoopRequester::start() {
diff --git a/esphome/core/helpers.h b/esphome/core/helpers.h
index 2e6a978012..4699e8071c 100644
--- a/esphome/core/helpers.h
+++ b/esphome/core/helpers.h
@@ -120,10 +120,6 @@ std::string uint64_to_string(uint64_t num);
 /// Convert a uint32_t to a hex string
 std::string uint32_to_string(uint32_t num);
 
-uint8_t reverse_bits_8(uint8_t x);
-uint16_t reverse_bits_16(uint16_t x);
-uint32_t reverse_bits_32(uint32_t x);
-
 /// Convert RGB floats (0-1) to hue (0-360) & saturation/value percentage (0-1)
 void rgb_to_hsv(float red, float green, float blue, int &hue, float &saturation, float &value);
 /// Convert hue (0-360) & saturation/value percentage (0-1) to RGB floats (0-1)
@@ -343,6 +339,23 @@ inline std::array<uint8_t, sizeof(T)> decode_value(T val) {
   return ret;
 }
 
+/// Reverse the order of 8 bits.
+inline uint8_t reverse_bits(uint8_t x) {
+  x = ((x & 0xAA) >> 1) | ((x & 0x55) << 1);
+  x = ((x & 0xCC) >> 2) | ((x & 0x33) << 2);
+  x = ((x & 0xF0) >> 4) | ((x & 0x0F) << 4);
+  return x;
+}
+/// Reverse the order of 16 bits.
+inline uint16_t reverse_bits(uint16_t x) {
+  return (reverse_bits(static_cast<uint8_t>(x & 0xFF)) << 8) | reverse_bits(static_cast<uint8_t>((x >> 8) & 0xFF));
+}
+/// Reverse the order of 32 bits.
+inline uint32_t reverse_bits(uint32_t x) {
+  return (reverse_bits(static_cast<uint16_t>(x & 0xFFFF)) << 16) |
+         reverse_bits(static_cast<uint16_t>((x >> 16) & 0xFFFF));
+}
+
 /// Convert a value between host byte order and big endian (most significant byte first) order.
 template<typename T, enable_if_t<std::is_unsigned<T>::value, int> = 0> constexpr T convert_big_endian(T val) {
 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__