Re: driver_attach question

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, Dec 13, 2005 at 06:07:54PM -0800, Anil kumar wrote:
> Hi,
> 
> Should driver_attach( ) return an error value?
> 
> I have disabled a device in the system bios, The
> driver fails to report -ENODEV.
> This is for 2.6.11.1 kernel
> When I dig through the PCI subsystem and driver_attach
> code, I find that :
> 
> pci_register_driver is returing zero(no error) even
> when the device is not present in the system. 
> But when I check driver_attach( ), I get -ENODEV for
> driver_probe_device(). which is correct. But
> driver_attach( ) does not return this error value. 
> driver attach( ) is called in bus_add_driver( ) and
> bus_add_driver just returns error=0
> Hence I get error=0 in pci_register_driver.
> 
> Am I missing something in the flow?

The basic strategy is to leave the driver loaded so that
later, if the a device is hotplugged or the user adds a
dynamic id to an existing device, it will be available.
In other words, even if the registration of a driver does
not result in device detection, the operation can still
considered successful.

Does this answer your question?

Thanks,
Adam
-
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/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux