hal

I have problem with Android O HIDL. The failure log shows it can't find out the service. However I can see it by adb shell ps -A | grep fingerprint system 18758 1 17408 3276 pipe_wait 7c79e93e08 R android.hardware.biometrics.fingerprint@2.1-service` Could anyone give me a hint how to solve the problem? I checked https://source.android.com/devices/architecture/hidl/ but could not get the solution. Error log: 08-21 06:00:35.864 1890 2264 V FingerprintService: mDeamon was null, reconnect to fingerprint 08-21 06:00:35.864 1890 2264 I system_server: Looking for service android.hardware.biometrics

1. HAL介绍 Android的HAL（Hardware Abstract Layer硬件抽象层）是为了保护一些硬件提供商的知识产权而提出的，是为了避开linux的GPL束缚。思路是把控制硬件的动作都放到了Android HAL中，而linux driver仅仅完成一些简单的数据交互作用，甚至把硬件寄存器空间直接映射到user space。而Android是基于Aparch的license，因此硬件厂商可以只提供二进制代码，所以说Android只是一个开放的平台，并不是一个开源的平台。 总结下来，Android HAL存在的原因主要有： 并不是所有的硬件设备都有标准的linux kernel的接口 KERNEL DRIVER涉及到GPL的版权。某些设备制造商并不原因公开硬件驱动，所以才去用HAL方式绕过GPL。 针对某些硬件，Android有一些特殊的需求。 不同的平台厂商可在遵循HAL调用接口的前提下实现自己的HAL，不会影响到上层的调用者，这样降低了模块间的耦合度，可以让平台开发者只关心HAL本身的实现即可。 下图是HAL在android系统中所处的位置： 从这张图中可以看出，HAL把内核和framework隔离开来，使上层的开发可以不依赖内核与驱动的实现。在android源码中，HAL大致位于下面几个位置： libhardware_legacy/ - 旧的架构

I'm trying to figure out how to use this new HAL driver. I want to receive data using the HAL_UART_Receive_IT() which sets up the device to run an interrupt function when data is received. Problem is that you have to specify the length of data to read before the interrupt triggers. I plan on sending console like commands of varying length so can't have a fixed length. I assume the only way to do this would be to read single characters at a time and build up a separate string. The HAL driver seems to have a problem where if you set the HAL_UART_Receive_IT() to receive x number of characters,

Android 的 HAL 技術, #1: 簡介與發展現況 Android 的 HAL（硬體抽像層）是 Google 因應廠商「希望不公開源碼」的要求下，所推出的新觀念，其架構如下圖。雖然 HAL 現在的「抽象程度」還不足，現階段實作還不是全面符合 HAL 的架構規劃，不過也確實給了我們很好的思考空間。 圖1：Android HAL 架構規劃 這是 Patrick Brady (Google) 在2008 Google I/O 所發表的演講「 Anatomy & Physiology of an Android 」 中，所提出的 Android HAL 架構圖。從這張架構圖我們知道，HAL 的目的是為了把 Android framework 與 Linux kernel 完整「隔開」。讓 Android 不至過度依賴 Linux kernel，有點像是「kernel independent」的意思，讓 Android framework 的開發能在不考量驅動程式的前提下進行發展。 在 Android 原始碼裡，HAL 主要的實作儲存於以下目錄： 1. libhardware_legacy/ - 過去的實作、採取程式庫模組的觀念進行 2. libhardware/ - 新版的實作、調整為 HAL stub 的觀念 3. ril/ - Radio Interface Layer 在

I am writing a new Android Audio HAL, to let my App to feed audio to other apps, to allow my handheld remote microphone input to reach Google app. Essentially, a Virtual Audio Cable. Its a work in progress. I'll probably be overriding AUDIO_DEVICE_IN_BACK_MIC, but this is open for suggestions. I have doubts on how to make sure Android uses this HAL for input. Do I need to replace audio.primary.default.so or should I leave it as audio.vcable.default.so? More specifically: If I am not replacing primary, how will Android know to use my HAL instead of primary? Update: I could really use any help

I'm building a Spring REST application using Spring HATEOAS (0.16.0.RELEASE) and I'd like the JSON links output to look like: _links: { self: { href: "https://<ip>/api/policies/321" } } while it renders like: "links": [{ "rel":"self", "href":"http://<ip>/api/policies/321" }] I'm using HATEOAS Resource and ResourceAssembler . Why do I get this format instead of the other? How can I change it? In order to use HAL as the message format language for our RESTful API, and enable automatic pagination, we need some configuration changes in our applicaiton. Since Spring Data and Spring HATEOAS already

http://technet.microsoft.com/en-us/sysinternals/bb963892.aspx Introduction There are number of BOOT.INI switches that are useful for driver developers that wish to test their drivers under a variety of different system configurations without having to have a separate machine for every one. For example, limiting the amount of memory NT sees can be useful for stressing memory loads, and limiting the number of processors for testing scalability. I've compiled a complete list of the options that BOOT.INI currently supports. This list is reproduced in the Startup, Shutdown and Crashes chapter of