[fix] Update AutoWarmth state on resume (#4901)

Regression since #4871
Fix #4895

* Hide the "Configure" button in the FL/NL widget on devices where it
won't do anything

(i.e., those w/ a NL mixer).

frontend/device/cervantes/device.lua

@@ -50,6 +50,7 @@ local Cervantes = Generic:new{
 
     -- currently only Cervantes 4 has coloured frontlight
     hasNaturalLight = no,
+    hasNaturalLightMixer = no,
 }
 -- Cervantes Touch
 local CervantesTouch = Cervantes:new{
@@ -131,6 +132,12 @@ end
 
 function Cervantes:init()
     self.screen = require("ffi/framebuffer_mxcfb"):new{device = self, debug = logger.dbg}
+
+    -- Automagically set this so we never have to remember to do it manually ;p
+    if self:hasNaturalLight() and self.frontlight_settings and self.frontlight_settings.frontlight_mixer then
+        self.hasNaturalLightMixer = yes
+    end
+
     self.powerd = require("device/cervantes/powerd"):new{device = self}
     self.input = require("device/input"):new{
         device = self,

frontend/device/kobo/device.lua

@@ -38,6 +38,7 @@ local Kobo = Generic:new{
     internal_storage_mount_point = "/mnt/onboard/",
     -- currently only the Aura One and Forma have coloured frontlights
     hasNaturalLight = no,
+    hasNaturalLightMixer = no,
     -- HW inversion is generally safe on Kobo, except on a few baords/kernels
     canHWInvert = yes,
 }
@@ -255,6 +256,12 @@ function Kobo:init()
         logger.info("Enabling Kobo @ 32bpp BGR tweaks")
         self.hasBGRFrameBuffer = yes
     end
+
+    -- Automagically set this so we never have to remember to do it manually ;p
+    if self:hasNaturalLight() and self.frontlight_settings and self.frontlight_settings.frontlight_mixer then
+        self.hasNaturalLightMixer = yes
+    end
+
     self.powerd = require("device/kobo/powerd"):new{device = self}
     -- NOTE: For the Forma, with the buttons on the right, 193 is Top, 194 Bottom.
     self.input = require("device/input"):new{

frontend/device/kobo/powerd.lua

@@ -141,6 +141,10 @@ function KoboPowerD:init()
         -- See discussion in https://github.com/koreader/koreader/issues/3118#issuecomment-334995879
         -- for the reasoning behind this bit of insanity.
         if self:isFrontlightOnHW() then
+            -- On devices with a mixer, setIntensity will *only* set the FL, so, ensure we honor the warmth, too.
+            if self.device:hasNaturalLightMixer() then
+               self:setWarmth(self.fl_warmth)
+            end
             -- Use setIntensity to ensure it sets fl_intensity, and because we don't want the ramping behavior of turnOn
             self:setIntensity(self:frontlightIntensityHW())
         else
@@ -253,6 +257,18 @@ function KoboPowerD:calculateAutoWarmth()
         self.fl_warmth = math.max(100 - 50 * (22 - diff_time), 0)
     end
     self.fl_warmth = math.floor(self.fl_warmth + 0.5)
+    -- Make sure sysfs_light actually picks that new value up without an explicit setWarmth call...
+    -- This avoids having to bypass the ramp-up on resume w/ an explicit setWarmth call on devices where brightness & warmth
+    -- are linked (i.e., when there's no mixer) ;).
+    -- NOTE: A potentially saner solution would be to ditch the internal sysfs_light current_* values,
+    --       and just pass it a pointer to this powerd instance, so it has access to fl_warmth & hw_intensity.
+    --       It seems harmless enough for warmth, but brightness might be a little trickier because of the insanity
+    --       that is hw_intensity handling because we can't actually *read* the frontlight status...
+    --       (Technically, we could, on Mk. 7 devices, but we don't,
+    --       because this is already messy enough without piling on special cases.)
+    if self.fl then
+        self.fl.current_warmth = self.fl_warmth
+    end
     -- Enable background job for setting Warmth, if not already done.
     if not self.autowarmth_job_running then
         table.insert(PluginShare.backgroundJobs, {
@@ -320,6 +336,14 @@ end
 -- Restore front light state after resume.
 function KoboPowerD:afterResume()
     if self.fl == nil then return end
+    -- Update AutoWarmth state
+    if self.fl_warmth ~= nil and self.auto_warmth then
+        self:calculateAutoWarmth()
+        -- And we need an explicit setWarmth if the device has a mixer, because turnOn won't touch the warmth on those ;).
+        if self.device:hasNaturalLightMixer() then
+            self:setWarmth(self.fl_warmth)
+        end
+    end
     -- Turn the frontlight back on
     self:turnOnFrontlight()
 end

frontend/ui/widget/frontlightwidget.lua

@@ -52,7 +52,8 @@ function FrontLightWidget:init()
         self.steps = self.steps + 1
     end
     self.steps = math.min(self.steps, steps_fl)
-    self.natural_light = (Device:isCervantes() or Device:isKobo()) and Device:hasNaturalLight()
+    self.natural_light = Device:hasNaturalLight()
+    self.has_nl_mixer = Device:hasNaturalLightMixer()
     -- Handle Warmth separately, because it may use a different scale
     if self.natural_light then
         self.nl_min = self.powerd.fl_warmth_min
@@ -256,21 +257,23 @@ function FrontLightWidget:setProgress(num, step, num_warmth)
     table.insert(vertical_group, button_group_down)
     table.insert(vertical_group, padding_span)
     if self.natural_light then
-        -- If the device supports natural light, add the widgets for 'warmth'
-        -- and a 'Configure' button
+        -- If the device supports natural light, add the widgets for 'warmth',
+        -- as well as a 'Configure' button for devices *without* a mixer
         self:addWarmthWidgets(num_warmth, step, vertical_group)
-        self.configure_button =  Button:new{
-            text = _("Configure"),
-            margin = Size.margin.small,
-            radius = 0,
-            width = self.screen_width * 0.20,
-            enabled = not self.nl_configure_open,
-            show_parent = self,
-            callback = function()
-                UIManager:show(NaturalLight:new{fl_widget = self})
-            end,
-        }
-        table.insert(vertical_group, self.configure_button)
+        if not self.has_nl_mixer then
+            self.configure_button =  Button:new{
+                text = _("Configure"),
+                margin = Size.margin.small,
+                radius = 0,
+                width = self.screen_width * 0.20,
+                enabled = not self.nl_configure_open,
+                show_parent = self,
+                callback = function()
+                    UIManager:show(NaturalLight:new{fl_widget = self})
+                end,
+            }
+            table.insert(vertical_group, self.configure_button)
+        end
     end
     table.insert(self.fl_container, vertical_group)
     -- Reset container height to what it actually contains