From mboxrd@z Thu Jan 1 00:00:00 1970 From: Takashi Iwai Subject: Re: trying out usb hotplugs Date: Fri, 29 Nov 2002 11:07:54 +0100 Sender: alsa-devel-admin@lists.sourceforge.net Message-ID: References: Mime-Version: 1.0 (generated by SEMI 1.14.4 - "Hosorogi") Content-Type: text/plain; charset=US-ASCII Return-path: In-Reply-To: Errors-To: alsa-devel-admin@lists.sourceforge.net List-Help: List-Post: List-Subscribe: , List-Unsubscribe: , List-Archive: To: Jaroslav Kysela Cc: Clemens Ladisch , "alsa-devel@lists.sourceforge.net" List-Id: alsa-devel@alsa-project.org At Fri, 29 Nov 2002 10:39:22 +0100 (CET), Jaroslav wrote: > > On Fri, 29 Nov 2002, Takashi Iwai wrote: > > > At Fri, 29 Nov 2002 08:52:43 +0100 (MET), > > Clemens Ladisch wrote: > > > > > > Takashi Iwai wrote: > > > > Martin Langer wrote: > > > > > usb hotplug works perfect if my usbmidi client isn't aconnected to another > > > > > midi client. But the aconnected usb midi device still remains in the clients > > > > > list, after hotpluging out. > > > > > > > > yep, when the connection exists, the connected devices (on both > > > > sides) are regarded as active. > > > > > > The sequencer design allows asynchronous removal of clients. > > > > yes, but this may still try to send some bytes to the unplugged > > rawmidi device at the disconnection. i'll change rawmidi code to > > ignore that. > > Well, I'm trying to solve these "hotplug" problems. Unfortunately, it > seems difficult to detect, if another task is in the middle of our > callback. I think that we'll end up using mutexes. hmm, but mutex costs too much even for non-pluggable devices... in the case of rawmidi and oss-mixer, we can put "disconnected" flag and ignore the access if the flag is on at the rawmidi and oss-mixer routines, so that the control doesn't reach to low-level functions. at least, the sequencer connection problem seems ok. i'm checking now whether it can work for oss-mixer, too. Takashi ------------------------------------------------------- This SF.net email is sponsored by: Get the new Palm Tungsten T handheld. Power & Color in a compact size! http://ads.sourceforge.net/cgi-bin/redirect.pl?palm0002en