From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pedro Lopez-Cabanillas Date: Thu, 01 May 2003 18:57:05 +0000 Subject: Re: Hotplug loads USB audio before local audio Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-hotplug@vger.kernel.org On Thursday 01 May 2003 17:32, Joshua Pollak wrote: > Just to clarify, this problem is not particular to ALSA. I don't believe > RedHat 9.0 uses ALSA, I think the driver that is being loaded is the stock > Linux kernel one. Yes, 'audio' is the OSS module for USB audio devices. OTOH, i think that your problem is not particular to audio, OSS or ALSA. The problem is that you have two devices of the same class, one of them supported by hotplug (or both). For instance: if you get some internal PCI TV card using a V4L driver (as bt878), and you have also an USB webcam... How can you know which is your webcam /dev/video0 or /dev/video1 ? if you boot with your USB cam plugged, then it is /dev/video0, but if you boot with it unplugged the node /dev/video0 is your TV card, and /dev/video1 will be the webcam if you plug it later. Same for printers, scanners, disks (i guess). If you have several USB devices of the same class, you can also go into troubles with your apps configured to use one device or another, by his device node in /dev directory. ALSA driver snd-usb-audio has some support to solve this issue, with two params to specify the device order by manufacturer and model ids, but i don't know about other drivers. Of course, you can avoid to use hotplug to load your device driver (/etc/hotplug/blacklist) or renounce to use it (alias off in modules.conf). The SuSE approach gives you some hotplug support, loading the drivers with the classic ALSA startup script. The problem is that you need to maintain the alsa.usermap file by hand as the set of devices supported by the snd-usb-audio driver grows (and it grows very quickly!). Planet CCRMA (stanford.edu) has a set of RPM packages for multimedia Red Hat users, using /etc/hotplug/blacklist for audio, too. David: I think that some kind of general solution for this problem should be included in hotplug (if there is one). Regards, Pedro -- ALSA Library Bindings for Pascal http://alsapas.alturl.com ------------------------------------------------------- This sf.net email is sponsored by:ThinkGeek Welcome to geek heaven. http://thinkgeek.com/sf _______________________________________________ Linux-hotplug-devel mailing list http://linux-hotplug.sourceforge.net Linux-hotplug-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel