On Thu, 28 Jan 2016, Ulf Hansson wrote: > On 28 January 2016 at 11:20, Russell King - ARM Linux > <linux@xxxxxxxxxxxxxxxx> wrote: > >> - free_irq(host->irq, host); > >> + disable_irq(host->irq); > > > > This is really not acceptable I'm afraid. While it's common on ARM for > > each interrupt to be uniquely allocated to a peripheral, not all SDHCI > > platforms have that luxury. > > > > SDHCI is also used on PCI, and on x86 platforms, it's common to have PCI > > interrupts shared between (sometimes many) different PCI devices. > > > > For example, on my laptop: > > > > 18: 1089806 286185 IO-APIC-fasteoi uhci_hcd:usb8, r852, mmc0 > > > > the SDHCI interrupt is shared with two other peripherals - one USB > > controller and a NAND device. > > > > Disabling the interrupt will adversely impact other peripherals and > > cause regressions where the interrupt is shared. > > I thought disable|enable_irq() was being reference counted, so it > shouldn't impact the other peripherals for shared IRQs. I might have > understood this wrong though!? It's reference counted. But it disables the irq line and not a particular interrupt handler. > Although, as if that's the case it also means that the IRQ can still > reach sdhci's irq handler as it hasn't actually been disabled. No. The result is that the other devices on the same irq line won't get any interrupt anymore. > Therefore, the only way we currently can make sure to don't get the > IRQ is to free and later re-request it. Now, apparently that has > issues when using threaded IRQ handlers. What's the issue? Thanks, tglx -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
