Return-Path: MIME-Version: 1.0 In-Reply-To: References: From: =?UTF-8?Q?Fran=C3=A7ois_Beaufort?= Date: Wed, 30 Sep 2015 16:43:59 +0200 Message-ID: Subject: Re: Disabling deviceinfo plugin on chromebooks? To: Luiz Augusto von Dentz Cc: "linux-bluetooth@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-bluetooth-owner@vger.kernel.org List-ID: On Wed, Sep 30, 2015 at 4:24 PM, Luiz Augusto von Dentz wrote: > Hi François, > > On Wed, Sep 30, 2015 at 4:54 PM, François Beaufort > wrote: >> Thanks for your answer Luiz! > > Please comment inline in the ml. > >> From what I can see, Android and iOS Bluetooth Stack libraries don't >> claim the device_information service. >> Could it be possible to make it so that the plugin doesn't block other >> clients (such as the Web Bluetooth API) from interacting with that >> service. > > That probably a bad behavior in their own because it can only cause > more traffic as this information can be cached and made available > without causing any extra traffic, as I said I think we just need to > expose the extra information over the device API, so we just have to > add them here: > > https://webbluetoothcg.github.io/web-bluetooth/#bluetoothdevice (note > that it already contains part of device information) > As these characteristics might not be useful to everyone, I'm not sure about the benefit of caching all these device_information service characteristics in Bluez and exposing them to the bluetooth device object. >From a web developer point of view, I think I want to get back as quick as possible the bluetooth device object and get characteristics afterwards when I need to. >> Also, do you know if other services (like device_information) are >> blocked/claimed by other plugins? > > iirc GAP, GATT and HoG services are claimed by bluetoothd, and the > fact that we claim these services is on purpose so applications cannot > make conflicting changes or cause unnecessary traffic. > Thank you! >> On Tue, Sep 22, 2015 at 12:05 PM Luiz Augusto von Dentz >> wrote: >>> >>> Hi François, >>> >>> On Tue, Sep 22, 2015 at 11:41 AM, François Beaufort >>> wrote: >>> > As the chromium team is building and testing the Web Bluetooth API to >>> > let websites discover and interact with nearby Bluetooth devices >>> > (https://developers.google.com/web/updates/2015/07/interact-with-ble-devices-on-the-web) >>> > I would love to be able to access the Device Information Service >>> > characteristics such as Serial Number String, Hardware Revision String >>> > and so forth. >>> >>> Looks like we don't parse these characteristics just PnP ID which is >>> expose via Modalias property that has the information of product id >>> and vendor id, etc. >>> >>> > Sadly, from what I understood, this is not achievable for now on >>> > Chromeboooks since Bluez comes with the deviceinfo plugin enabled by >>> > default. I do wonder now what would be the implications of disabling >>> > the deviceinfo plugin? >>> >>> The way it works is that the plugin claims this service which prevent >>> it to be accessible over D-Bus, you could in theory disable the plugin >>> but I think we would benefit more if we add support for the missing >>> information directly in BlueZ saving each application the trouble to >>> read this information themselves. >>> >>> If I would do it in BlueZ Id probably add them as properties to >>> org.bluez.Device1 and make sure we store them as we do with PnP ID. >>> >>> > You will find more information at >>> > https://code.google.com/p/chromium/issues/detail?id=532930 >>> > >>> > Thank you in advance, >>> > Francois - a daily Bluez user. >>> > -- >>> > To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in >>> > the body of a message to majordomo@vger.kernel.org >>> > More majordomo info at http://vger.kernel.org/majordomo-info.html >>> >>> >>> >>> -- >>> Luiz Augusto von Dentz > > > > -- > Luiz Augusto von Dentz