From db666e44a7756f50d60202ac84019bc9a338eab6 Mon Sep 17 00:00:00 2001
From: Jesse Hills <3060199+jesserockz@users.noreply.github.com>
Date: Mon, 3 Mar 2025 15:35:52 +1300
Subject: [PATCH] [ltr390] Move calculation to allow dynamic setting of gain
 and resolution (#8343)

---
 esphome/components/ltr390/ltr390.cpp | 14 +++++++-------
 esphome/components/ltr390/ltr390.h   |  1 -
 2 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/esphome/components/ltr390/ltr390.cpp b/esphome/components/ltr390/ltr390.cpp
index 198d15ebd8..84b2eba2de 100644
--- a/esphome/components/ltr390/ltr390.cpp
+++ b/esphome/components/ltr390/ltr390.cpp
@@ -1,7 +1,7 @@
 #include "ltr390.h"
+#include <bitset>
 #include "esphome/core/hal.h"
 #include "esphome/core/log.h"
-#include <bitset>
 
 namespace esphome {
 namespace ltr390 {
@@ -91,7 +91,12 @@ void LTR390Component::read_uvs_() {
   uint32_t uv = *val;
 
   if (this->uvi_sensor_ != nullptr) {
-    this->uvi_sensor_->publish_state((uv / this->sensitivity_uv_) * this->wfac_);
+    // Set sensitivity by linearly scaling against known value in the datasheet
+    float gain_scale_uv = GAINVALUES[this->gain_uv_] / GAIN_MAX;
+    float intg_scale_uv = (RESOLUTIONVALUE[this->res_uv_] * 100) / INTG_MAX;
+    float sensitivity_uv = SENSITIVITY_MAX * gain_scale_uv * intg_scale_uv;
+
+    this->uvi_sensor_->publish_state((uv / sensitivity_uv) * this->wfac_);
   }
 
   if (this->uv_sensor_ != nullptr) {
@@ -166,11 +171,6 @@ void LTR390Component::setup() {
     return;
   }
 
-  // Set sensitivity by linearly scaling against known value in the datasheet
-  float gain_scale_uv = GAINVALUES[this->gain_uv_] / GAIN_MAX;
-  float intg_scale_uv = (RESOLUTIONVALUE[this->res_uv_] * 100) / INTG_MAX;
-  this->sensitivity_uv_ = SENSITIVITY_MAX * gain_scale_uv * intg_scale_uv;
-
   // Set sensor read state
   this->reading_ = false;
 
diff --git a/esphome/components/ltr390/ltr390.h b/esphome/components/ltr390/ltr390.h
index 24afd3c411..7359cbd336 100644
--- a/esphome/components/ltr390/ltr390.h
+++ b/esphome/components/ltr390/ltr390.h
@@ -77,7 +77,6 @@ class LTR390Component : public PollingComponent, public i2c::I2CDevice {
   LTR390GAIN gain_uv_;
   LTR390RESOLUTION res_als_;
   LTR390RESOLUTION res_uv_;
-  float sensitivity_uv_;
   float wfac_;
 
   sensor::Sensor *light_sensor_{nullptr};