Hello! On 12/10/21 1:44 PM, Andy Shevchenko wrote: >>>>>>> While at it, drop redundant check for 0 as platform_get_irq() spills >>>>>>> out a big WARN() in such case. >>>>>> >>>>>> And? IRQ0 is still returned! :-( >>>>> >>>>> It should not be returned in the first place. >>>> >>>> But it still is, despite the WARN(), right? >>> >>> So, you admit that there is a code which does that? >> >> I admit *what*?! That platfrom_get_irq() and its ilk return IRQ0 while they >> shouldn't? =) > > That there is a code beneath platform_get_irq() that returns 0, yes. Look at the ACPI-specific GpioInt handling code (just above the out_not_found label) -- I'm not sure the check there is correct -- I'm not very familiar with ACPI, you seem to know it much better. :-) Also, 0 can be specified via the normal IRQ resource. I know of e.g. the Alchemy MIPS SoCs that have IRQ0 used by UART0; luckily, currently SoC IRQs are mapped starting at Linux IRQ8 (but it wasn't the case in the 2.6.1x time frame where we had issue with the serial driver)... >>> That code should be fixed first. Have you sent a patch? >> >> Which code?! You got me totally muddled. =) > > Above mentioned. What needs to be fixed in this case is the interrupt controller driver. Quoting Linus (imprecisely :-)), IRQ #s should be either mapped starting with #1 or IRQ0 remapped at the end of the controller's interrupt range... I currently have no information on the platforms requiring such kind of fixing (Alchemy don't seem to need it now)... > ... > >>>>>>> - if (!irq) >>>>>>> - return -EINVAL; >>>>>> >>>>>> This is prermature -- let's wait till my patch that stops returning IRQ0 from >>>>>> platform_get_irq() and friends gets merged.... >>>>> >>>>> What patch? >>>> >>>> https://marc.info/?l=linux-kernel&m=163623041902285 >>>> >>>>> Does it fix platform_get_irq_optional()? >>>> >>>> Of course! :-) >>> >>> Can you share link to lore.kernel.org, please? >>> It will make much easier to try and comment. >> >> I don't know how to uise it yet, and I'm a little busy with other IRQ0 issues ATM, A little bit, I meant to type. >> so I'm afraid you're on your own here... > > lore.kernel.org is the official mailing list archive for Linux kernel work > AFAIU. Other sites may do whatever they want with that information, so --> > they are unreliable. If you wish to follow the better process, use > lore.kernel.org. Understanding how it works takes no more than 5 minutes > by engineer with your kind of experience with Linux kernel development. OK, I'll explore this archive when I have time. BTW, does it keep the messages not posted to LKML (I tend to only CC LKML if there's no other mailing lists to post to)? MBR, Sergey
