Date: Thu, 22 Mar 2001 05:18:50 +0600 (NOVT) From: Alexey Dokuchaev <danfe@inet.ssc.nsu.ru> To: Mike Smith <msmith@freebsd.org> Cc: freebsd-hackers@freebsd.org Subject: Re: Some PCI-related programming things Message-ID: <Pine.LNX.4.10.10103220509220.26570-100000@inet.ssc.nsu.ru> In-Reply-To: <200103212304.f2LN4lh03035@mass.dis.org>
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On Wed, 21 Mar 2001, Mike Smith wrote: > > > > Did I say I'm doing it from userspace?! If I did (too lazy to dig into > > > > sent-mail), I beg your pardon :) > > > > > > Your FreeBSD sample involved making an ioctl call, so it must have been > > > from userspace. > > > > Is anything wrong with using ioctl calls from device driver? > > Perhaps a more polite answer is called for. 8) > > Ioctls allow user processes to make function calls within a device > driver; they are a mechanism for exporting functionality from a device > driver out into userspace. I know that, of course. > You don't call them from other device drivers, no. There are exported > interfaces inside the kernel for doing this, and you will understand > everything much better if you go look at a simple FreeBSD PCI device > driver, particularly the _probe and _attach functions. Look, I am *not* coding a PCI driver. I have looked at various examples in sound/pci/ and I know what PCI device driver should look like. What I am doing is *porting* linux *character* device driver to FreeBSD. That is, if original version called all that linuxish pci_whatever() functions, I have to provide the same functionality under FreeBSD. I didn't know how to do this. What I did was, I said man pci, from there I figured out about pciconf utility. I took a look at it, and thought, ok, this must be the way I have to go for under FreeBSD. At first, I thought I calling ioctl's from kernel space is probably at least weird idea (if not to call it bad). But I was unable to find any PCI-related doc which would answer my questions. Trust me, if I wanted to code a PCI dev driver, I would certainly not do this. I have a code to take a look at, and I only ask questions when I seem to fail to comprehend going of things from the code. It's not written anywhere I can't use ioctl from char device driver. Or is it? -- Me To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message
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