On Wed, 10 Oct 2007 09:39:44 +0800 wit <[EMAIL PROTECTED]> wrote: > Hi, > I found these routines in the kernel, does this means only one driver > can be matched to a device? What if two drivers both can drive the > device, like sd & sg in scsi subsystem?
The first one which matches and successfully attaches "wins". Thus you can allow two drivers to match an identifier and load either one or the other. You can also deal with cases where the same identifier is used for two different devices (eg with the revision id distinguishing them), by having the probe methods fail if the revision is wrong. For things like sd/sg this isn't an issue. The hardware driver interfaces to the scsi layer which itself provides interfaces for sd, sr, sg, ... etc If you have a PCI device with multiple device functions on one PCI function it can be a problem. We have some special case drivers for serial/parallel multiport cards for exactly this reason, and some ugly hacks in AGP and EDAC that arise from this limit. Alan - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
