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@linux....