Russell, Colin, The Tegra Harmony board contains a TPS6586x chip, which has an active-low interrupt output. This is then fed to Tegra's PMC's PWR_INT pin, which can be programmed to accept active-low or active-high interrupt signals. This then feeds into a GIC interrupt. The problem is that the PMC appears to default to expecting the attached signal to be active-high not active-low. At a driver level, it seems that IRQF_TRIGGER_LEVEL_LOW should be passed to request_threaded_irq() to solve this. However, gic.c:gic_set_type() prohibits IRQ_TYPE_* except LEVEL_HIGH and EDGE_RISING. I'm not quite sure how to solve this; should gic_set_type() be modified to remove the restriction if gic_arch_extn.irq_set_type is present, and assume that gic_arch_extn.irq_set_type will handle converting the input signal from LEVEL_LOW to LEVEL_HIGH or EDGE_FALLING to EDGE_RISING? In at least some non-mainline kernels, this has been solved by having individual board files poke PMC registers to invert the signal to the gic's expected LEVEL_HIGH. However, I assume that's not a good solution for mainline. Thanks. -- nvpublic -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
