Revert "pro1: lights: Enable support for keyboard brightness control"

This reverts commit cb7cc707eb3d2ac6dfa8281dd6dd3c30a01c5922.

Backlight support has _not_ been added to Android frameworks in AICP.

4 files changed, 106 insertions, 13 deletions

diff --git a/light/Light.cpp b/light/Light.cpp
index f2ed9d1..b04a783 100644
--- a/light/Light.cpp
+++ b/light/Light.cpp
@@ -18,7 +18,11 @@
 
 #include "Light.h"
 
+#include <fcntl.h>
+#include <sys/inotify.h>
+
 #include <android-base/logging.h>
+#include <linux/input.h>
 
 namespace {
 
@@ -52,6 +56,40 @@ static std::string getScaledDutyPcts(int brightness) {
     return buf;
 }
 
+static int openInputDeviceByName(const char* name) {
+    int fd;
+    unsigned int n;
+    char pathname[PATH_MAX];
+    char devname[256];
+
+    fd = -1;
+    n = 0;
+    while (fd < 0) {
+        sprintf(pathname, "/dev/input/event%u", n++);
+        fd = TEMP_FAILURE_RETRY(open(pathname, O_RDONLY | O_CLOEXEC));
+        if (fd < 0) {
+            // Fail: out of devices to try
+            break;
+        }
+        memset(devname, 0, sizeof(devname));
+        if (ioctl(fd, EVIOCGNAME(sizeof(devname) - 1), &devname) > 0) {
+            if (!strcmp(devname, name)) {
+                // Success
+                break;
+            }
+        }
+        close(fd);
+        fd = -1;
+    }
+
+    return fd;
+}
+
+static bool readEvent(int fd, input_event& ev) {
+    ssize_t len = TEMP_FAILURE_RETRY(read(fd, &ev, sizeof(ev)));
+    return (len == sizeof(ev));
+}
+
 }  // anonymous namespace
 
 namespace android {
@@ -60,6 +98,39 @@ namespace light {
 namespace V2_0 {
 namespace implementation {
 
+static void* sliderMonitorThread(void* arg) {
+    Light* owner = (Light*)arg;
+    int fd;
+
+restart:
+    fd = openInputDeviceByName("gpio-keys");
+    if (fd < 0) {
+        LOG(ERROR) << "Cannot open slider input device";
+        sleep(1);
+        goto restart;
+    }
+
+    LOG(INFO) << "sliderMonitorThread enter loop";
+    while (1) {
+        struct input_event ev;
+        if (!readEvent(fd, ev)) {
+            LOG(ERROR) << "Failed to read slider event";
+            close(fd);
+            sleep(1);
+            goto restart;
+        }
+        // Ignore unwanted event types and codes (eg. EV_SYN)
+        if (ev.type != EV_SW || ev.code != SW_LID) {
+            continue;
+        }
+        bool open = (ev.value == 0);
+        owner->onSliderChanged(open);
+    }
+    close(fd);
+
+    return nullptr;
+}
+
 static const std::string kSysLedPath = "/sys/class/leds";
 
 Led::Led(int index, const std::string& name) :
@@ -126,17 +197,20 @@ Light::Light(std::pair<std::ofstream, uint32_t>&& lcd_backlight,
       mRedLed(std::move(red_led)),
       mGreenLed(std::move(green_led)),
       mBlueLed(std::move(blue_led)),
-      mRgbBlink(std::move(rgb_blink)) {
+      mRgbBlink(std::move(rgb_blink)),
+      mLcdBacklightOn(false),
+      mSliderOpen(false) {
     auto attnFn(std::bind(&Light::setAttentionLight, this, std::placeholders::_1));
-    auto keyboardBacklightFn(std::bind(&Light::setKeyboardBacklight, this, std::placeholders::_1));
-    auto lcdBacklightFn(std::bind(&Light::setLcdBacklight, this, std::placeholders::_1));
+    auto backlightFn(std::bind(&Light::setLcdBacklight, this, std::placeholders::_1));
     auto batteryFn(std::bind(&Light::setBatteryLight, this, std::placeholders::_1));
     auto notifFn(std::bind(&Light::setNotificationLight, this, std::placeholders::_1));
     mLights.emplace(std::make_pair(Type::ATTENTION, attnFn));
-    mLights.emplace(std::make_pair(Type::BACKLIGHT, lcdBacklightFn));
+    mLights.emplace(std::make_pair(Type::BACKLIGHT, backlightFn));
     mLights.emplace(std::make_pair(Type::BATTERY, batteryFn));
-    mLights.emplace(std::make_pair(Type::KEYBOARD, keyboardBacklightFn));
     mLights.emplace(std::make_pair(Type::NOTIFICATIONS, notifFn));
+
+    pthread_t th;
+    (void)pthread_create(&th, nullptr, sliderMonitorThread, this);
 }
 
 // Methods from ::android::hardware::light::V2_0::ILight follow.
@@ -164,6 +238,12 @@ Return<void> Light::getSupportedTypes(getSupportedTypes_cb _hidl_cb) {
     return Void();
 }
 
+void Light::onSliderChanged(bool open) {
+    std::lock_guard<std::mutex> lock(mLock);
+    mSliderOpen = open;
+    setKeyboardBacklightLocked();
+}
+
 void Light::setAttentionLight(const LightState& state) {
     std::lock_guard<std::mutex> lock(mLock);
     mAttentionState = state;
@@ -173,6 +253,8 @@ void Light::setAttentionLight(const LightState& state) {
 void Light::setLcdBacklight(const LightState& state) {
     std::lock_guard<std::mutex> lock(mLock);
 
+    mLcdBacklightOn = (state.color != 0);
+
     uint32_t brightness = rgbToBrightness(state);
 
     // If max panel brightness is not the default (255),
@@ -184,14 +266,18 @@ void Light::setLcdBacklight(const LightState& state) {
     }
 
     mLcdBacklight.first << brightness << std::endl;
-}
 
-void Light::setKeyboardBacklight(const LightState& state) {
-    std::lock_guard<std::mutex> lock(mLock);
-
-    uint32_t brightness = isLit(state) ? MAX_BRIGHTNESS : 0;
+    setKeyboardBacklightLocked();
+}
 
-    mKeyboardBacklight.first << brightness << std::endl;
+void Light::setKeyboardBacklightLocked() {
+    mKeyboardBacklight.second = (mSliderOpen && mLcdBacklightOn)
+                                ? MAX_BRIGHTNESS
+                                : 0;
+    LOG(INFO) << "setKeyboardBacklightLocked:" <<
+                 " mSliderOpen=" << (mSliderOpen ? "true" : "false") <<
+                 " mLcdBacklightOn=" << (mLcdBacklightOn ? "true" : "false");
+    mKeyboardBacklight.first << mKeyboardBacklight.second << std::endl;
 }
 
 void Light::setBatteryLight(const LightState& state) {
diff --git a/light/Light.h b/light/Light.h
index a5884e2..72a6d76 100644
--- a/light/Light.h
+++ b/light/Light.h
@@ -69,11 +69,13 @@ struct Light : public ILight {
     Return<Status> setLight(Type type, const LightState& state) override;
     Return<void> getSupportedTypes(getSupportedTypes_cb _hidl_cb) override;
 
+    void onSliderChanged(bool open);
+
   private:
     void setAttentionLight(const LightState& state);
     void setBatteryLight(const LightState& state);
-    void setKeyboardBacklight(const LightState& state);
     void setLcdBacklight(const LightState& state);
+    void setKeyboardBacklightLocked();
     void setNotificationLight(const LightState& state);
     void setSpeakerBatteryLightLocked();
     void setSpeakerLightLocked(const LightState& state);
@@ -91,6 +93,9 @@ struct Light : public ILight {
 
     std::unordered_map<Type, std::function<void(const LightState&)>> mLights;
     std::mutex mLock;
+
+    bool mLcdBacklightOn;
+    bool mSliderOpen;
 };
 
 }  // namespace implementation
diff --git a/light/android.hardware.light@2.0-service.pro1.rc b/light/android.hardware.light@2.0-service.pro1.rc
index a607a79..90d2914 100644
--- a/light/android.hardware.light@2.0-service.pro1.rc
+++ b/light/android.hardware.light@2.0-service.pro1.rc
@@ -57,6 +57,6 @@ service vendor.light-hal-2-0 /vendor/bin/hw/android.hardware.light@2.0-service.p
     interface android.hardware.light@2.0::ILight default
     class hal
     user system
-    group system
+    group system input
     # shutting off lights while powering-off
     shutdown critical
diff --git a/sepolicy/vendor/hal_light_default.te b/sepolicy/vendor/hal_light_default.te
new file mode 100644
index 0000000..72fe06d
--- /dev/null
+++ b/sepolicy/vendor/hal_light_default.te
@@ -0,0 +1,2 @@
+allow hal_light_default input_device:dir search;
+allow hal_light_default input_device:chr_file rw_file_perms;