On Fri, 2015-01-09 at 17:16 +0100, Lars-Peter Clausen wrote: > On 01/09/2015 05:14 PM, Ivan T. Ivanov wrote: > > On Fri, 2015-01-09 at 16:54 +0100, Lars-Peter Clausen wrote: > > > On 01/09/2015 04:50 PM, Ivan T. Ivanov wrote: > > > > On Fri, 2015-01-09 at 16:41 +0100, Lars-Peter Clausen wrote: > > > > > On 01/09/2015 04:38 PM, Ivan T. Ivanov wrote: > > > > > > Instead of checking whether provider module is still > > > > > > loaded on every access to device just lock module to > > > > > > memory when client get reference to provider device. > > > > > > > > > > > > > > > > This has nothing to do with the module, it's about the device. In the Linux > > > > > device driver model as device can be unbound at any time and the IIO > > > > > framework needs to handle this. > > > > > > > > > > > > > Hm. Probably i am missing something here, but is this > > > > still true if we have reference to device structure? > > > > > > Yes, that only prevents the memory of device from being freed. But the > > > device can still be unbound from the driver. > > > > > > Think of e.g. a USB device that is pulled from the USB connector. Nothing > > > you can do in software about having the device disappear. > > > > > > > Agree, but I think that the patch is still valid. Module > > have to be pinned in memory as long as there are device > > driver users. > > No, the idea of the Linux driver model is that you can remove the module of > a driver at any time, which will unbind the device from the driver. Once you > reinsert the module the device will be re-bound to the driver. I will say that device can be unbind at any time and not that module be can unload at any time. But yes, and I'm not saying the opposite. There are a lot of examples in kernel, where you can not unload driver if it is used by another driver. See kernel-haking.tmpl. Probably I am still missing something :-) Ivan -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
