Date: Mon, 16 Sep 2013 18:11:38 +0200 From: Harald Schmalzbauer <h.schmalzbauer@omnilan.de> To: lev@FreeBSD.org, FreeBSD Stable <freebsd-stable@FreeBSD.org> Subject: umcs (4-Port-USB-serial) triggering way too much ehci IRQs Message-ID: <52372DBA.6020703@omnilan.de>
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[-- Attachment #1 --] Hello, I have some of these 4-Port-Serial-USB-Hubs: http://www.delock.com/produkte/F_673_USB---Seriell_87414/merkmale.html They have the MosChip MCS7840 inside, wich also understands RS485/422 besides RS232. FreeBSDs umcs(4) supports the RS232 mode with standard baudrates and works with that device. Unfortunately, as soon as I open any of the 4 cuaU0.x ports, there are 500irq/s from ehci. These irqs also accur if the port is closed again (until I unload the umcs module). These irqs prevent virtual machines and also real hardware from deeper sleeping. In my case, it's a huge ammount of lost power saving. I also saw that the windows driver of the MCS7840 consuming a lot of CPU-cycles (XP-ESXi guest). Is there any chance to tranquilize? The 4-Port prolific model (http://www.delock.com/produkte/F_673_USB---Seriell_61518/merkmale.html) doesn't show these unneccessary irqs btw.! Thanks, -Harry [-- Attachment #2 --] -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.18 (FreeBSD) iEYEARECAAYFAlI3LcIACgkQLDqVQ9VXb8g/TgCgwIFNO5QSoKm7+JwJc3mLLlg9 nQwAnAxoZe5qUydATd5ryBrLChlheiSA =anbH -----END PGP SIGNATURE-----
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