Date: Wed, 23 Feb 2005 15:31:29 +0100 From: Divacky Roman <xdivac02@stud.fit.vutbr.cz> To: arch@freebsd.org Subject: Re: Better device probe values Message-ID: <20050223143129.GA23805@stud.fit.vutbr.cz> In-Reply-To: <20050222.143230.41648746.imp@bsdimp.com> References: <20050222.143230.41648746.imp@bsdimp.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Tue, Feb 22, 2005 at 02:32:30PM -0700, Warner Losh wrote:
> Greetings,
>
> >From time to time, the concept of a binary driver has been floated.
> The idea would be that a vendor could put out a binary driver disk
> when there were bugs in the drivers for a specific release so that
> users impacted by those bugs could still, for example, install that
> specific release.
>
> However, most of the drivers in the base system do not allow this to
> happen because they return 0.
>
> At the same time, we have a number of generic drivers in the tree that
> have been using ad-hoc values to make sure that the right driver gets
> attached (see for example pci and acpi pci, and friends). We also
> have some drivers that overlap ranges of devices (eg, ncr and sym
> drivers).
>
> So, I'd like to standardize on some names, and thought I'd post here
> my first cut at the names. Let's not get too far off in the weeds,
> since names is a prime bike-shed topic[*]. I'll likely ignore most of
> that part of the discussion, and focus on the more technical and/or
> political side of things. If possible, I'd like to have this wrapped
> up in time for 5.4, but I do understand that time is extremely short
> for that.
>
> /**
> * Some convenience defines for probe routines to return. These are
> * just suggested values, and there's nothing magical about them.
> * BUS_PROBE_SPECIFIC is for devices that cannot be reprobed, and that
> * no possible other driver may exist (typically legacy drivers who
> * don't fallow all the rules, or special needs drivers). BUS_PROBE_VENDOR
> * is the suggested value that vendor supplied drivers use. This is
> * for source or binary drivers that are not yet integrated into the FreeBSD
> * tree. Its use in the base OS is prohibited. BUS_PROBE_DEFAULT is
> * the normal return value for drivers to use. It is intended that nearly
> * all of the drivers in the tree should return this value.
> * BUS_PROBE_LOW_PRIORITY are for drivers that have special requirements
> * like when there are two drivers that support overlapping series of
> * hardware devices. In this case the one that supports the older part
> * of the line would return this value, while the one that supports the newer
> * ones would return BUS_PROBE_DEFAULT. BUS_PROBE_GENERIC is for drivers
> * that wish to have a generic form and a specialized form, like is done
> * with the pci bus and that acpi pci bus. BUS_PROBE_HOOVER is for those
> * busses that implement a generic device placeholder for devices on the
> * bus that have no more specific driver for them (aka ugen).
> */
> #define BUS_PROBE_SPECIFIC 0 /* Only I can use this device */
> #define BUS_PROBE_VEDNOR (-10) /* Vendor supplied driver */
^^
typo...
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20050223143129.GA23805>