> > > ... > > > > > > > > This change reveals potential issue: > > > > > > > > > > > - irq = of_irq_get_byname(adapter->dev.of_node, > "smbus_alert"); > > > > > > + irq = > > > > > > + device_irq_get_byname(adapter->dev.parent, > > > "smbus_alert"); > > > > > > > > > > > if (irq <= 0) > > > > > > > > > > I guess this '= 0' part should be fixed first. > > > > > > > > '0' is a failure as per the documentation of of_irq_get_byname() > > > > as well as of_irq_get(). The case is different for acpi_irq_get(), > > > > but it is handled in fwnode_irq_get(). If I understood it right, a > > > > return value of '0' should be considered a failure here. > > > > > > Depends. I have no idea what the original code does here. But > > > returning an error or 0 from this function seems confusing to me. > > > > > The description in of_irq_get*() says - > > /* Return: Linux IRQ number on success, or 0 on the IRQ mapping > > failure, or > > * -EPROBE_DEFER if the IRQ domain is not yet created, or error code > > in case > > * of any other failure. > > */ > > As I see from the code of fwnode_irq_get(), which is used in this > > case, returns either the return value of of_irq_get() or error code > > from acpi_irq_get() when it fails, or res.start if it didn't fail. I > > guess, any of these would not be 0 unless there is an error. > > of_irq_get*() seems inconsistent... > > Uwe, what do you think? > A bit tricky. You are right, as we don't often see a return value of '0' as an error in Linux. But here since it is a number which is expected, it might be reasonable to allot 0 to an error as well. Not sure of the exact rationale in those functions though. Thanks, Akhil
