On 03/06/2014 07:16 PM, Florian Fainelli wrote: > 2014-03-06 0:51 GMT-08:00 Christian Riesch <christian.rie...@omicron.at>: >> --On March 06, 2014 13:57 +0530 Mugunthan V N <mugunthan...@ti.com> wrote: >>> >>> On Wednesday 05 March 2014 03:55 PM, Christian Riesch wrote: >>>> >>>> In commit 6892b41d9701283085b655c6086fb57a5d63fa47 >>>> >>>> Author: Lad, Prabhakar <prabhakar.cse...@gmail.com> >>>> Date: Tue Jun 25 21:24:51 2013 +0530 >>>> net: davinci: emac: Convert to devm_* api >>>> >>>> the call of request_irq is replaced by devm_request_irq and the call >>>> of free_irq is removed. But since interrupts are requested in >>>> emac_dev_open, doing ifconfig up/down on the board requests the >>>> interrupts again each time, causing devm_request_irq to fail. >>>> >>>> This patch reverts said commit partially: It changes the driver back >>>> to use request_irq instead of devm_request_irq, puts free_irq back in >>>> place, but keeps the remaining changes of the original patch. >>>> >>>> Reported-by: Jon Ringle <j...@ringle.org> >>>> Signed-off-by: Christian Riesch <christian.rie...@omicron.at> >>>> Cc: Lad, Prabhakar <prabhakar.cse...@gmail.com> >>>> Cc: <sta...@vger.kernel.org> >>> >>> >>> Instead of moving back to request irq. can you move the devm interrupt >>> request code from open to probe so that the issue is fixed, IRQ will be >>> requested on module insert and IRQ will be free in module remove and >>> there will not be any failures in devm request irq while repeating >>> ifup/ifdown and also during module insert/remove. >> >> >> This is exactly what I tried first, please have a look at my first patch and >> the discussion [1]. Florian Fainelli asked me to revert Prabhakar's patch >> instead to bring back the "usual situation", "just in case some uncontrolled >> interrupt bit triggers an interrupt while the interface is down for >> instance..." >> >> Florian Fainelli, Mugunthan VN, which solution is better? > > I think the solution that does: > > - request_irq() in ndo_open() > - free_irq() in ndo_stop() > > is the safest option because it ensure that the various interrupt > lines are masked at the interrupt controller level, and not just at > Ethernet MAC level, and as such gives you more control over what the > hardware does. It also mimics what 99% of the Ethernet drivers do, > which will help identifying those common patterns programmatically. >
Why are you not using enable_irq()/disable_irq()? Also, IRQ_NOAUTOEN can be used irq_set_status_flags(IRQ_NOAUTOEN); before [devm_]request_irq(). The normal way is to request resources from .rpobe(), use them and free on .remove(). Actually, I've found at least one example - drivers/net/ethernet/apple/bmac.c Regards, - grygorii _______________________________________________ Davinci-linux-open-source mailing list Davinci-linux-open-source@linux.davincidsp.com http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
