sm6225-common: Add notification light HAL

The otherwise unused charging-LED is used as notification light with
configurable pulse-widths.

Change-Id: Ic6c7cf993b8e83793b191d24cff65320c68d40d0

lights/Android.bp

@@ -0,0 +1,24 @@
+//
+// Copyright (C) 2023 The LineageOS Project
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+cc_binary {
+    name: "android.hardware.lights-service.bengal",
+    relative_install_path: "hw",
+    init_rc: ["android.hardware.lights.bengal.rc"],
+    vintf_fragments: ["android.hardware.lights.bengal.xml"],
+    vendor: true,
+    shared_libs: [
+        "libbase",
+        "liblog",
+        "libhardware",
+        "libbinder_ndk",
+        "android.hardware.light-V1-ndk",
+    ],
+    srcs: [
+        "Lights.cpp",
+        "main.cpp",
+    ],
+}

lights/Lights.cpp

@@ -0,0 +1,148 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ * Copyright (C) 2023 The LineageOS Project
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include "Lights.h"
+#include <android-base/file.h>
+#include <android-base/logging.h>
+#include <thread>
+
+/* clang-format off */
+#define PPCAT_NX(A, B) A/B
+#define PPCAT(A, B) PPCAT_NX(A, B)
+#define STRINGIFY_INNER(x) #x
+#define STRINGIFY(x) STRINGIFY_INNER(x)
+
+#define CHARGING_ATTR(x) STRINGIFY(PPCAT(/sys/class/leds/charging, x))
+/* clang-format on */
+
+namespace aidl {
+namespace android {
+namespace hardware {
+namespace light {
+
+namespace {
+
+using ::android::base::WriteStringToFile;
+
+// Write value to path and close file.
+template <typename T>
+inline bool WriteToFile(const std::string& path, T content) {
+    return WriteStringToFile(std::to_string(content), path);
+}
+
+uint32_t RgbaToBrightness(uint32_t color) {
+    // Extract brightness from AARRGGBB.
+    uint32_t alpha = (color >> 24) & 0xFF;
+
+    // Retrieve each of the RGB colors
+    uint32_t red = (color >> 16) & 0xFF;
+    uint32_t green = (color >> 8) & 0xFF;
+    uint32_t blue = color & 0xFF;
+
+    // Scale RGB colors if a brightness has been applied by the user
+    if (alpha != 0xFF && alpha != 0) {
+        red = red * alpha / 0xFF;
+        green = green * alpha / 0xFF;
+        blue = blue * alpha / 0xFF;
+    }
+
+    return (77 * red + 150 * green + 29 * blue) >> 8;
+}
+
+inline bool IsLit(uint32_t color) {
+    return color & 0x00ffffff;
+}
+
+void ApplyNotificationState(const HwLightState& state) {
+    bool ok = false;
+    uint32_t brightness = RgbaToBrightness(state.color);
+
+    switch (state.flashMode) {
+        case FlashMode::HARDWARE:
+        case FlashMode::TIMED:
+            ok = WriteStringToFile("timer", CHARGING_ATTR(trigger));
+            if (ok) {
+                using namespace std::chrono_literals;
+                auto retries = 20;
+                while (retries--) {
+                    std::this_thread::sleep_for(2ms);
+
+                    ok = WriteToFile(CHARGING_ATTR(delay_off), state.flashOffMs);
+                    if (!ok) continue;
+
+                    ok = WriteToFile(CHARGING_ATTR(delay_on), state.flashOnMs);
+                    if (ok) break;
+                }
+                LOG(DEBUG) << __func__
+                    << ": number of tries to write delay: " << (20 - retries);
+            }
+            if (ok) break;
+            // fallback to constant on if timed blinking is not supported
+            LOG(INFO) << __func__
+                << ": fallthrough FlashMode::TIMED to FlashMode::NONE.";
+            FALLTHROUGH_INTENDED;
+        case FlashMode::NONE:
+        default:
+            ok = WriteToFile(CHARGING_ATTR(brightness), brightness);
+            break;
+    }
+
+    LOG(DEBUG) << __func__
+               << ": mode=" << toString(state.flashMode) << ", colorRGB=" << std::hex
+               << state.color << std::dec << ", onMS=" << state.flashOnMs
+               << ", offMS=" << state.flashOffMs << ", ok=" << ok
+               << ", brightnessMode=" << toString(state.brightnessMode);
+}
+
+}  // anonymous namespace
+
+ndk::ScopedAStatus Lights::setLightState(int id, const HwLightState& state) {
+    static_assert(kAvailableLights.size() == std::tuple_size_v<decltype(notif_states_)>);
+
+    if (id == static_cast<int32_t>(LightType::BACKLIGHT)) {
+        // Stub backlight handling
+        return ndk::ScopedAStatus::ok();
+    }
+
+    // Update saved state first
+    bool found = false;
+    for (size_t i = 0; i < notif_states_.size(); ++i) {
+        if (kAvailableLights[i].id == id) {
+            notif_states_[i] = state;
+            found = true;
+            break;
+        }
+    }
+    if (!found) {
+        LOG(ERROR) << " Light not supported";
+        return ndk::ScopedAStatus::fromExceptionCode(EX_UNSUPPORTED_OPERATION);
+    }
+
+    // Lit up in order or fallback to battery light if others are dim
+    for (size_t i = 0; i < notif_states_.size(); ++i) {
+        auto&& cur_state = notif_states_[i];
+        auto&& cur_light = kAvailableLights[i];
+        if (IsLit(cur_state.color) || cur_light.type == LightType::BATTERY) {
+            ApplyNotificationState(cur_state);
+            break;
+        }
+    }
+
+    return ndk::ScopedAStatus::ok();
+}
+
+ndk::ScopedAStatus Lights::getLights(std::vector<HwLight>* lights) {
+    lights->insert(lights->end(), kAvailableLights.begin(), kAvailableLights.end());
+    // We don't handle backlight but still need to report as supported.
+    lights->push_back({static_cast<int32_t>(LightType::BACKLIGHT), 2, LightType::BACKLIGHT});
+    return ndk::ScopedAStatus::ok();
+}
+
+}  // namespace light
+}  // namespace hardware
+}  // namespace android
+}  // namespace aidl

lights/Lights.h

@@ -0,0 +1,39 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ * Copyright (C) 2023 The LineageOS Project
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#pragma once
+
+#define LOG_TAG "android.hardware.lights-service.bengal"
+
+#include <aidl/android/hardware/light/BnLights.h>
+#include <array>
+
+namespace aidl {
+namespace android {
+namespace hardware {
+namespace light {
+
+// Keep sorted in the order of priority.
+constexpr std::array kAvailableLights = {
+        // id, ordinal, type
+        HwLight{static_cast<int32_t>(LightType::NOTIFICATIONS), 0, LightType::NOTIFICATIONS},
+        HwLight{static_cast<int32_t>(LightType::BATTERY), 1, LightType::BATTERY},
+};
+
+class Lights : public BnLights {
+  public:
+    ndk::ScopedAStatus setLightState(int id, const HwLightState& state) override;
+    ndk::ScopedAStatus getLights(std::vector<HwLight>* types) override;
+
+  private:
+    std::array<HwLightState, kAvailableLights.size()> notif_states_;
+};
+
+}  // namespace light
+}  // namespace hardware
+}  // namespace android
+}  // namespace aidl

lights/android.hardware.lights.bengal.rc

@@ -0,0 +1,16 @@
+service vendor.light-default /vendor/bin/hw/android.hardware.lights-service.bengal
+    class hal
+    user system
+    group system
+    shutdown critical
+
+on boot
+    # Change ownership and permission for charging led
+    chown system system /sys/class/leds/charging/breath
+    chown system system /sys/class/leds/charging/brightness
+    chown system system /sys/class/leds/charging/delay_off
+    chown system system /sys/class/leds/charging/delay_on
+    chmod 0640 /sys/class/leds/charging/breath
+    chmod 0640 /sys/class/leds/charging/brightness
+    chmod 0640 /sys/class/leds/charging/delay_off
+    chmod 0640 /sys/class/leds/charging/delay_on

lights/android.hardware.lights.bengal.xml

@@ -0,0 +1,6 @@
+<manifest version="1.0" type="device">
+    <hal format="aidl">
+        <name>android.hardware.light</name>
+        <fqname>ILights/default</fqname>
+    </hal>
+</manifest>

lights/main.cpp

@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include "Lights.h"
+
+#include <android-base/logging.h>
+#include <android/binder_manager.h>
+#include <android/binder_process.h>
+
+using ::aidl::android::hardware::light::Lights;
+
+int main() {
+    ABinderProcess_setThreadPoolMaxThreadCount(0);
+    std::shared_ptr<Lights> lights = ndk::SharedRefBase::make<Lights>();
+    if (!lights) {
+        return EXIT_FAILURE;
+    }
+
+    const std::string instance = std::string() + Lights::descriptor + "/default";
+    binder_status_t status = AServiceManager_addService(lights->asBinder().get(), instance.c_str());
+    CHECK(status == STATUS_OK);
+
+    ABinderProcess_joinThreadPool();
+    return EXIT_FAILURE;  // should not be reached
+}

rootdir/etc/ueventd.qcom.rc

@@ -390,6 +390,11 @@ firmware_directories /vendor/firmware_mnt/image/
 /sys/class/leds/blue     breath       0640    system    system
 /sys/class/leds/blue     trigger      0640    system    system
 
+/sys/class/leds/charging    delay_on     0640    system    system
+/sys/class/leds/charging    delay_off    0640    system    system
+/sys/class/leds/charging    breath       0640    system    system
+/sys/class/leds/charging    trigger      0640    system    system
+
 # LED class vibrator
 /sys/class/leds/vibrator state        0660    system    system
 /sys/class/leds/vibrator duration     0660    system    system

sepolicy/vendor/file_contexts

@@ -47,6 +47,9 @@
 /dev/focaltech_fp                                       u:object_r:fps_device:s0
 /dev/fpsensor                                           u:object_r:fps_device:s0
 
+# Lights
+/(vendor|system/vendor)/bin/hw/android\.hardware\.lights-service\.bengal      u:object_r:hal_light_default_exec:s0
+
 # Motobox
 /(vendor|system/vendor)/bin/motobox                     u:object_r:vendor_motobox_exec:s0
 

sepolicy/vendor/genfs_contexts

@@ -32,6 +32,9 @@ genfscon sysfs /devices/platform/soc/soc:mmi_chrg_manager/iio:device
 # Input Devices
 genfscon sysfs /devices/virtual/input                                           u:object_r:vendor_sysfs_input:s0
 
+# Lights
+genfscon sysfs /devices/platform/soc/soc:indicator_led/leds/charging            u:object_r:sysfs_leds:s0
+
 # Motorola
 genfscon proc /bootinfo                                                         u:object_r:proc_moto_boot:s0
 genfscon proc /config                                                           u:object_r:vendor_proc_hw:s0

sepolicy/vendor/hal_light_default.te

@@ -0,0 +1,5 @@
+allow hal_light_default {
+  sysfs_leds
+}:file rw_file_perms;
+
+r_dir_file(hal_light_default, sysfs_leds)