Messages in this thread |  | | From | "Mahadev K Cholachagudda" <> | Subject | Re: Interrupt sharing | Date | Tue, 26 Sep 2000 08:55:19 +0530 |
| |
----- Original Message ----- From: "Jeff Garzik" <jgarzik@mandrakesoft.mandrakesoft.com> To: "Mahadev K Cholachagudda" <mahadev_kc@yahoo.com> Cc: <linux-kernel@vger.kernel.org> Sent: Monday, September 25, 2000 7:00 PM Subject: Re: Interrupt sharing
> > > On Mon, 25 Sep 2000, Mahadev K Cholachagudda wrote: > > > Hello to all, > > > > I have one doubt and is as below. > > > > > > Suppose say the two drivers driver1 and driver2 will install the ISR for a > > particular interrupt, say UART0. > > After some time the interrupt is generated. At this moment, which driver's > > ISR is going to execute ?. > > > > If driver1 ISR is get executed, will the driver2's ISR is going to execute > > ?. If say driver2's ISR is going to execute, Is the data that interrupt > > generated is going to be emulated to the driver2's ISR. > > When an interrupt is delivered, the kernel calls ALL interrupt handlers > registered for that interrupt. That means all drivers capable of > sharing interrupts should, ideally, have code in their interrupt handler > to exit ASAP if no work is necessary. > > status = RTL_R16(IntrStatus); > /* exit ASAP if no interrupt conditions (0), or > * if the hardware was unplugged (0xFFFF) > */ > if ((status == 0) || (status == 0xFFFF)) > return; >
If this is the case, if i am not wrong the data which is to be delivered to the ISR will be emulated to the each drivers ISR. Is it true ?
_________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/
|  |