Return-Path: MIME-Version: 1.0 In-Reply-To: References: <20150417220040.A379A220209@puck.mtv.corp.google.com> Date: Mon, 20 Apr 2015 09:34:31 -0700 Message-ID: Subject: Re: [PATCH 2/3] hog: re-enable HoG report notifications on HoG device reconnect From: Petri Gynther 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: Hi Luiz, On Mon, Apr 20, 2015 at 7:50 AM, Luiz Augusto von Dentz wrote: > Hi Petri, > > On Sat, Apr 18, 2015 at 1:00 AM, Petri Gynther wrote: >> On HoG device reconnect, re-enable HoG report notifications every >> time by writing the client characteristic configuration attribute >> of each HoG report. >> >> Doing this on every reconnect: >> 1. ensures that HoG report notifications are always enabled >> (e.g. lost report notification state in battery swap). >> 2. signals to HoG device that it can start sending HoG reports >> (e.g. buffered keypresses while the reconnect is still pending). > > Is that happening for a specific device? For 1 I suppose it would > loose the paring keys as well which means we would not be able to > connect at all as HoG mandates pairing, or does it loose only the CCC > configuration? Reason 2 is not necessary the behavior every device > would have, for example I don't expect a mouse to buffer anything and > even a keyboard may buffer only the last key pressed since it might > have very little memory to spend in buffering, anyway I suppose reason > 1 is what you should really concentrate to tell us what is going on. > On the device that I'm working on, pairing info is stored in persistent storage, so it survives battery swap. However, I'm not sure yet about HoG report notification enable/disable state. Waiting for confirmation from vendor. Anyways, we are seeing (2). The first keypress from HoG device is getting lost on reconnect, leading to bad user experience. The device is sending the keypress immediately when the connection is good, but too early before BlueZ has managed to re-register the handler with g_attrib_register(). During the reconnect, the HoG device has no way of knowing when BlueZ is ready and has registered the handler. So, to provide this indication, I propose to re-enable the HoG report notification every time. >> --- >> profiles/input/hog.c | 5 +---- >> 1 file changed, 1 insertion(+), 4 deletions(-) >> >> diff --git a/profiles/input/hog.c b/profiles/input/hog.c >> index c55443c..690fd43 100644 >> --- a/profiles/input/hog.c >> +++ b/profiles/input/hog.c >> @@ -842,10 +842,7 @@ static void attio_connected_cb(GAttrib *attrib, gpointer user_data) >> for (l = hogdev->reports; l; l = l->next) { >> struct report *r = l->data; >> >> - r->notifyid = g_attrib_register(hogdev->attrib, >> - ATT_OP_HANDLE_NOTIFY, >> - r->decl->value_handle, >> - report_value_cb, r, NULL); >> + enable_report_notification(r); >> } >> } >> >> -- >> 2.2.0.rc0.207.ga3a616c >> >> -- >> 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