Date: Tue, 28 Mar 2000 20:42:51 -0500 From: "David E. Cross" <crossd@cs.rpi.edu> To: Mike Smith <msmith@FreeBSD.ORG> Cc: "David E. Cross" <crossd@cs.rpi.edu>, freebsd-current@FreeBSD.ORG, crossd@cs.rpi.edu Subject: Re: Major # please :) Message-ID: <200003290154.UAA87769@cs.rpi.edu> In-Reply-To: Message from Mike Smith <msmith@FreeBSD.ORG> of "Tue, 28 Mar 2000 17:33:13 PST." <200003290133.RAA03201@mass.cdrom.com>
next in thread | previous in thread | raw e-mail | index | archive | help
> Meaning no offense, but I can't think of a single good reason to write a > device driver for one of these cards. (Unless you're trying to do > pattern generation, and an 8255 is a terrible choice for that.) Worse > than that though, there's _no_ standard for these cards' implementation, > so a driver isn't going to be even vageuly portable. > > Use i386_set_ioperm() and just bit-bash it in userspace. The bit-bashing in userspace will make this even less portable. The idea is liked by those around here of being able to do a 'set register 0', or 'clear register 0' with an ioctl() and leaving the implementation to "something else", which can key on what type of board it is and DtRT. Also, how would you trap interrupts from such a card (for when using it as a digital input) from userland? Since it is already written, and in operation. Unless we are low on major numbers, or this could be better merged with another interface, it seems to be a waste to not give it a major number. Bringing it into the base CVS tree is another question entirely, but it would appear at least one has already expressed an interest. BTW: the URL for the card that was given to me for this project is at: http://www.computerboards.com/cbicatalog/cbiproduct.asp?dept%5Fid=224&pf%5Fid=668&mscssid=50A6V97GWTSH2J6N000JU4JKRUFAAEGB Product descriptions and a technical manual are linked from that page. -- David Cross | email: crossd@cs.rpi.edu Acting Lab Director | NYSLP: FREEBSD Systems Administrator/Research Programmer | Web: http://www.cs.rpi.edu/~crossd Rensselaer Polytechnic Institute, | Ph: 518.276.2860 Department of Computer Science | Fax: 518.276.4033 I speak only for myself. | WinNT:Linux::Linux:FreeBSD To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200003290154.UAA87769>