Manu Abraham wrote: > On Sat, Jan 16, 2010 at 3:00 AM, Oliver Endriss <o.endriss@xxxxxx> wrote: > >> Devin Heitmueller wrote: >> >>> On Thu, Jan 14, 2010 at 11:01 AM, Andreas Besse <besse@xxxxxxxxxx> wrote: >>> >>>> yes if there are different drivers I already observed the behaviour that >>>> the ordering gets flipped after reboot. >>>> >>>> But if I assume, that there is only *one* driver that is loaded (e.g. >>>> budget_av) for all dvb cards in the system, how is the ordering of these >>>> devices determined? How does the driver "search" for available dvb cards? >>>> >> The driver does not 'search' for a card. The driver registers the ids of >> all supported cards with the pci subsystem of the kernel. >> >> When the pci subsystem detects a new card, it calls the 'probe' routine >> of the driver (for example saa7146_init_one for saa7146-based cards). >> So the ordering is determined by the pci subsystem. >> >> >>> I believe your assumption is incorrect. I believe the enumeration >>> order is not deterministic even for multiple instances of the same >>> driver. It is not uncommon to hear mythtv users complain that "I have >>> two PVR-150 cards installed in my PC and the order sometimes get >>> reversed on reboot". >>> >> Afaik the indeterministic behaviour is caused by udev, not by the >> kernel. We never had these problems before udev was introduced. >> > > > True, the ordering is not exactly the same everytime. One will need to > provide PCI Bus related info also to a practical udev configuration to > get things sorted out in a sane way, rather than anything else. > with "PCI Bus related info" you mean the KERNELS parameter which is reported by udevinfo? udevinfo -a -p $(udevinfo -q path -n /dev/dvb/adapter0/frontend0) [...] looking at parent device '/devices/pci0000:00/0000:00:1e.0/0000:08:00.0': KERNELS=="0000:08:00.0" SUBSYSTEMS=="pci" does this KERNELS parameter always match the Slot-Id of "lspci -vmm" ? Slot: 08:00.0 Class: Multimedia controller Vendor: Philips Semiconductors Device: SAA7146 SVendor: Technotrend Systemtechnik GmbH SDevice: S2-3200 Rev: 01 is it right that the Slot-Id is deterministic for PCI/PCIe based systems? -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html