On Mon, Nov 29, 2021 at 09:01:16PM +0200, Andy Shevchenko wrote: > On Mon, Nov 29, 2021 at 05:11:52PM +0000, Mark Brown wrote: > > On Mon, Nov 29, 2021 at 10:22:41AM -0600, Pierre-Louis Bossart wrote: > > > On 11/25/21 1:50 AM, Tang Bin wrote: > > > > > > In the function sst_platform_get_resources(), if platform_get_irq() > > > > failed, the return should not be zero, as the example in > > > > platform.c is > > > > * int irq = platform_get_irq(pdev, 0) > > > > * if (irq < 0) > > > > * return irq; > > > > So remove the redundant check to simplify the code. > > > > > Humm, it's a bit of a gray area. > > > > > the comments for platform_get_irq and platform_get_irq_optional say: > > > > > * Return: non-zero IRQ number on success, negative error number on failure. > > > > > but if you look at platform_get_irq_optional, there are two references > > > to zero being a possible return value: > > > > Zero is (or was, people were working on changing it partly due to > > confusion and partly due to moving to newer infrastructure which > > doesn't use it) a valid IRQ on some architectures. x86 wasn't one of > > those though, at least AFAIR. > > I guess it's about x86, but the API returns Linux virtual IRQ and 0 shouldn't > be among them (hardware IRQ != Linux virtual IRQ). Legacy x86 used 1:1 mapping > for ISA IRQs (lower 16) among which the Timer IRQ is 0. I believe that timer > code does not use any of those APIs (it most likely and IIRC has it hardcoded). > > Nevertheless, I have planned to make platform_irq_get_optional() to be optional > indeed, where we return 0 when there is no IRQ provided and error when it's a > real error happens. This needs to clean up the current (mis-)use of the API. Link for previous work: https://lore.kernel.org/lkml/20210331144526.19439-1-andriy.shevchenko@xxxxxxxxxxxxxxx/T/#u -- With Best Regards, Andy Shevchenko
