sdm845-common: Add a custom lights HAL

* This overrides stock liblights and fixes LCD backlight issues.

Change-Id: Iafa2ba2338932879b7a1dc480b50559e3328fd21

Android.bp

@@ -0,0 +1,3 @@
+subdirs = [
+    "light"
+]

light/Android.bp

@@ -0,0 +1,31 @@
+// Copyright (C) 2018 The LineageOS Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+cc_binary {
+    relative_install_path: "hw",
+    defaults: ["hidl_defaults"],
+    name: "android.hardware.light@2.0-service.xiaomi_sdm845",
+    init_rc: ["android.hardware.light@2.0-service.xiaomi_sdm845.rc"],
+    srcs: ["service.cpp", "Light.cpp"],
+    shared_libs: [
+        "android.hardware.light@2.0",
+        "libbase",
+        "libhardware",
+        "libhidlbase",
+        "libhidltransport",
+        "libhwbinder",
+        "liblog",
+        "libutils",
+    ],
+}

light/Light.cpp

@@ -0,0 +1,189 @@
+/*
+ * Copyright (C) 2018 The LineageOS Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "LightsService"
+
+#include "Light.h"
+
+#include <android-base/logging.h>
+#include <android-base/stringprintf.h>
+#include <fstream>
+
+namespace android {
+namespace hardware {
+namespace light {
+namespace V2_0 {
+namespace implementation {
+
+/*
+ * Write value to path and close file.
+ */
+template <typename T>
+static void set(const std::string& path, const T& value) {
+    std::ofstream file(path);
+    file << value;
+}
+
+/*
+ * Read from path and close file.
+ * Return def in case of any failure.
+ */
+template <typename T>
+static T get(const std::string& path, const T& def) {
+    std::ifstream file(path);
+    T result;
+
+    file >> result;
+    return file.fail() ? def : result;
+}
+
+static constexpr int kDefaultMaxBrightness = 255;
+static constexpr int kRampSteps = 50;
+static constexpr int kRampMaxStepDurationMs = 5;
+
+static uint32_t getBrightness(const LightState& state) {
+    uint32_t alpha, red, green, blue;
+
+    // Extract brightness from AARRGGBB
+    alpha = (state.color >> 24) & 0xff;
+
+    // Retrieve each of the RGB colors
+    red = (state.color >> 16) & 0xff;
+    green = (state.color >> 8) & 0xff;
+    blue = state.color & 0xff;
+
+    // Scale RGB colors if a brightness has been applied by the user
+    if (alpha != 0xff) {
+        red = red * alpha / 0xff;
+        green = green * alpha / 0xff;
+        blue = blue * alpha / 0xff;
+    }
+
+    return (77 * red + 150 * green + 29 * blue) >> 8;
+}
+
+static uint32_t rgbToBrightness(const LightState& state) {
+    uint32_t color = state.color & 0x00ffffff;
+    return ((77 * ((color >> 16) & 0xff))
+            + (150 * ((color >> 8) & 0xff))
+            + (29 * (color & 0xff))) >> 8;
+}
+
+Light::Light() {
+    mLights.emplace(Type::ATTENTION, std::bind(&Light::handleNotification, this, std::placeholders::_1, 0));
+    mLights.emplace(Type::BACKLIGHT, std::bind(&Light::handleBacklight, this, std::placeholders::_1));
+    mLights.emplace(Type::BATTERY, std::bind(&Light::handleNotification, this, std::placeholders::_1, 1));
+    mLights.emplace(Type::NOTIFICATIONS, std::bind(&Light::handleNotification, this, std::placeholders::_1, 2));
+}
+
+void Light::handleBacklight(const LightState& state) {
+    int maxBrightness = get("/sys/class/backlight/panel0-backlight/max_brightness", -1);
+    if (maxBrightness < 0) {
+        maxBrightness = kDefaultMaxBrightness;
+    }
+    uint32_t sentBrightness = rgbToBrightness(state);
+    uint32_t brightness = sentBrightness * maxBrightness / kDefaultMaxBrightness;
+    LOG(DEBUG) << "Writing backlight brightness " << brightness
+               << " (orig " << sentBrightness << ")";
+    set("/sys/class/backlight/panel0-backlight/brightness", brightness);
+}
+
+void Light::handleNotification(const LightState& state, size_t index) {
+    mLightStates.at(index) = state;
+
+    LightState stateToUse = mLightStates.front();
+    for (const auto& lightState : mLightStates) {
+        if (lightState.color & 0xffffff) {
+            stateToUse = lightState;
+            break;
+        }
+    }
+
+    uint32_t whiteBrightness = getBrightness(stateToUse);
+
+    uint32_t onMs = stateToUse.flashMode == Flash::TIMED ? stateToUse.flashOnMs : 0;
+    uint32_t offMs = stateToUse.flashMode == Flash::TIMED ? stateToUse.flashOffMs : 0;
+
+    auto getScaledDutyPercent = [](int brightness) -> std::string {
+        std::string output;
+        for (int i = 0; i <= kRampSteps; i++) {
+            if (i != 0) {
+                output += ",";
+            }
+            output += std::to_string(i * 100 * brightness / (kDefaultMaxBrightness * kRampSteps));
+        }
+        return output;
+    };
+
+    // Disable blinking to start
+    set("/sys/class/leds/white/blink", 0);
+
+    if (onMs > 0 && offMs > 0) {
+        uint32_t pauseLo, pauseHi, stepDuration;
+        if (kRampMaxStepDurationMs * kRampSteps > onMs) {
+            stepDuration = onMs / kRampSteps;
+            pauseHi = 0;
+        } else {
+            stepDuration = kRampMaxStepDurationMs;
+            pauseHi = onMs - kRampSteps * stepDuration;
+            pauseLo = offMs - kRampSteps * stepDuration;
+        }
+
+        set("/sys/class/leds/white/start_idx", 0);
+        set("/sys/class/leds/white/duty_pcts", getScaledDutyPercent(whiteBrightness));
+        set("/sys/class/leds/white/pause_lo", pauseLo);
+        set("/sys/class/leds/white/pause_hi", pauseHi);
+        set("/sys/class/leds/white/ramp_step_ms", stepDuration);
+
+        // Start blinking
+        set("/sys/class/leds/white/blink", 1);
+    } else {
+        set("/sys/class/leds/white/brightness", whiteBrightness);
+    }
+}
+
+Return<Status> Light::setLight(Type type, const LightState& state) {
+    auto it = mLights.find(type);
+
+    if (it == mLights.end()) {
+        return Status::LIGHT_NOT_SUPPORTED;
+    }
+
+    // Lock global mutex until light state is updated.
+    std::lock_guard<std::mutex> lock(mLock);
+
+    it->second(state);
+
+    return Status::SUCCESS;
+}
+
+Return<void> Light::getSupportedTypes(getSupportedTypes_cb _hidl_cb) {
+    std::vector<Type> types;
+
+    for (auto const& light : mLights) {
+        types.push_back(light.first);
+    }
+
+    _hidl_cb(types);
+
+    return Void();
+}
+
+}  // namespace implementation
+}  // namespace V2_0
+}  // namespace light
+}  // namespace hardware
+}  // namespace android

light/Light.h

@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2018 The LineageOS Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ANDROID_HARDWARE_LIGHT_V2_0_LIGHT_H
+#define ANDROID_HARDWARE_LIGHT_V2_0_LIGHT_H
+
+#include <android/hardware/light/2.0/ILight.h>
+#include <hardware/lights.h>
+#include <hidl/Status.h>
+#include <unordered_map>
+#include <mutex>
+
+namespace android {
+namespace hardware {
+namespace light {
+namespace V2_0 {
+namespace implementation {
+
+using ::android::hardware::Return;
+using ::android::hardware::Void;
+using ::android::hardware::hidl_vec;
+using ::android::hardware::light::V2_0::ILight;
+using ::android::hardware::light::V2_0::LightState;
+using ::android::hardware::light::V2_0::Status;
+using ::android::hardware::light::V2_0::Type;
+
+class Light : public ILight {
+  public:
+    Light();
+
+    Return<Status> setLight(Type type, const LightState& state) override;
+    Return<void> getSupportedTypes(getSupportedTypes_cb _hidl_cb) override;
+
+  private:
+    void handleBacklight(const LightState& state);
+    void handleNotification(const LightState& state, size_t index);
+
+    std::mutex mLock;
+    std::unordered_map<Type, std::function<void(const LightState&)>> mLights;
+    std::array<LightState, 3> mLightStates;
+};
+
+}  // namespace implementation
+}  // namespace V2_0
+}  // namespace light
+}  // namespace hardware
+}  // namespace android
+
+#endif  // ANDROID_HARDWARE_LIGHT_V2_0_LIGHT_H

light/android.hardware.light@2.0-service.xiaomi_sdm845.rc

@@ -0,0 +1,21 @@
+on boot
+    chown system system /sys/class/leds/white/brightness
+
+    chown system system /sys/class/leds/white/blink
+    chown system system /sys/class/leds/white/duty_pcts
+    chown system system /sys/class/leds/white/pause_hi
+    chown system system /sys/class/leds/white/pause_lo
+    chown system system /sys/class/leds/white/ramp_step_ms
+    chown system system /sys/class/leds/white/start_idx
+
+    chmod 660 /sys/class/leds/white/blink
+    chmod 660 /sys/class/leds/white/duty_pcts
+    chmod 660 /sys/class/leds/white/pause_hi
+    chmod 660 /sys/class/leds/white/pause_lo
+    chmod 660 /sys/class/leds/white/ramp_step_ms
+    chmod 660 /sys/class/leds/white/start_idx
+
+service light-hal-2-0 /system/bin/hw/android.hardware.light@2.0-service.xiaomi_sdm845
+    class hal
+    user system
+    group system

light/service.cpp

@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2018 The LineageOS Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "android.hardware.light@2.0-service.xiaomi_sdm845"
+
+#include <android-base/logging.h>
+#include <hidl/HidlTransportSupport.h>
+
+#include "Light.h"
+
+using android::hardware::configureRpcThreadpool;
+using android::hardware::joinRpcThreadpool;
+
+using android::hardware::light::V2_0::ILight;
+using android::hardware::light::V2_0::implementation::Light;
+
+using android::OK;
+using android::sp;
+using android::status_t;
+
+int main() {
+    status_t status;
+    sp<ILight> service = nullptr;
+
+    LOG(INFO) << "Light HAL service 2.0 is starting.";
+
+    service = new Light();
+    if (service == nullptr) {
+        LOG(ERROR) << "Can not create an instance of Light HAL Iface, exiting.";
+        goto shutdown;
+    }
+
+    configureRpcThreadpool(1, true /*callerWillJoin*/);
+
+    status = service->registerAsService();
+    if (status != OK) {
+        LOG(ERROR) << "Could not register service for Light HAL Iface (" << status << ")";
+        goto shutdown;
+    }
+
+    LOG(INFO) << "Light HAL service is ready.";
+    joinRpcThreadpool();
+    // Should not pass this line
+
+shutdown:
+    // In normal operation, we don't expect the thread pool to exit
+    LOG(ERROR) << "Light HAL service is shutting down.";
+    return 1;
+}

sdm845.mk

@@ -40,6 +40,10 @@ PRODUCT_PACKAGES += \
 PRODUCT_PACKAGES += \
     ims-ext-common
 
+# Lights
+PRODUCT_PACKAGES += \
+    android.hardware.light@2.0-service.xiaomi_sdm845
+
 # NFC
 PRODUCT_PACKAGES += \
     com.android.nfc_extras \

sepolicy/private/file_contexts

@@ -1,3 +1,6 @@
+# Custom HALs
+/system/bin/hw/android\.hardware\.light@2\.0-service\.xiaomi_sdm845    u:object_r:hal_light_sdm845_exec:s0
+
 # Files in rootfs
 /bt_firmware(/.*)?       u:object_r:bt_firmware_file:s0
 /dsp(/.*)?               u:object_r:adsprpcd_file:s0

sepolicy/private/hal_light_sdm845.te

@@ -0,0 +1,7 @@
+type hal_light_sdm845, coredomain, domain;
+hal_server_domain(hal_light_sdm845, hal_light)
+
+type hal_light_sdm845_exec, exec_type, file_type;
+init_daemon_domain(hal_light_sdm845)
+
+allow hal_light_sdm845 sysfs_leds:file rw_file_perms;