[LAU] setting up hardware priority

[Renato]

On Wed, 17 Aug 2011 09:59:40 +0200 (CEST)
Cedric Roux <sed at free.fr> wrote:

> ----- Original Message -----
> > From: "Renato" <rennabh at gmail.com>
> > To: "Clemens Ladisch" <clemens at ladisch.de>
> > Cc: "linux-audio-user" <linux-audio-user at lists.linuxaudio.org>
> > Sent: Tuesday, August 16, 2011 5:55:52 PM
> > Subject: Re: [LAU] setting up hardware priority
> > 
> > On Tue, 16 Aug 2011 17:34:40 +0200
> > Clemens Ladisch <clemens at ladisch.de> wrote:
> > 
> > > Renato wrote:
> > > > Hello, I'm trying to find out if plugging my USB soundcard in
> > > > different USB ports of my laptop makes any difference. If I got
> > > > it
> > > > right, I should choose the one with the lowest IRQ. So, with
> > > > "lspci
> > > > -v" I can see I have 4 "USB Controller" devices, each with their
> > > > own IRQ (lowest one is 16 which seems to be shared by video
> > > > card...) - but how do I know which one my sound card is plugged
> > > > into?
> 
> In /sys/devices/pciXXXXX, try:
> for i in `find|grep usb|grep product`; do echo $i; cat $i; done
> I only have /sys/devices/pci0000:00 here.
> It gives the name of the product, maybe it can help.
> Try other files too. For my usb key, I see:
> /sys/devices/pci0000:00/0000:00:1a.7/usb1/1-3> ls
> 1-3:1.0              bDeviceSubClass     configuration  idProduct
> remove authorized           bmAttributes        descriptors
> idVendor      serial avoid_reset_quirk    bMaxPacketSize0
> dev            manufacturer  speed bcdDevice
> bMaxPower           devnum         maxchild      subsystem
> bConfigurationValue  bNumConfigurations  devpath        power
> uevent bDeviceClass         bNumInterfaces      driver
> product       urbnum bDeviceProtocol      busnum
> ep_00          quirks        version
> 
> Also, run 'dmesg' when you plug your audio card and see what it says
> (if it says something).

Thanks Cedric, both these methods show which usb controller the device
is attached to. But I still have a problem; I have 4 "USB Controller" devices:

$ lspci -v |grep -i "usb controller" -A 2
00:1d.0 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #1 (rev 02) (prog-if 00 [UHCI])
	Subsystem: Acer Incorporated [ALI] Device 0090
	Flags: bus master, medium devsel, latency 0, IRQ 23
--
00:1d.1 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #2 (rev 02) (prog-if 00 [UHCI])
	Subsystem: Acer Incorporated [ALI] Device 0090
	Flags: bus master, medium devsel, latency 0, IRQ 19
--
00:1d.2 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #3 (rev 02) (prog-if 00 [UHCI])
	Subsystem: Acer Incorporated [ALI] Device 0090
	Flags: bus master, medium devsel, latency 0, IRQ 18
--
00:1d.3 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #4 (rev 02) (prog-if 00 [UHCI])
	Subsystem: Acer Incorporated [ALI] Device 0090
	Flags: bus master, medium devsel, latency 0, IRQ 16
--
00:1d.7 USB Controller: Intel Corporation N10/ICH 7 Family USB2 EHCI Controller (rev 02) (prog-if 20 [EHCI])
	Subsystem: Acer Incorporated [ALI] Device 0090
	Flags: bus master, medium devsel, latency 0, IRQ 23


and 4 physical USB ports on my laptop, but whichever I plug the soundcard into,
it's allways seen on the 1d.7 controller, which seems to be the only USB2 and of
course the one with the highest IRQ. However, when I try plugging in a USB bluetooth
dongle in different physical ports, it's seen on different Controllers by dmesg. So with
the dongle I have actually found which physical port is the 1d.3, which is the one
with the lowest IRQ, but when I attach the soundcard to it dmesg reports
it on 1d.7. How's that possible?

BTW is it possible to reassign IRQ somehow on a laptop? As I said previously
the IRQ 16 seems to be shared by the video card, and I read that's not good.

thanks again to everyone for help so far,
renato