Re: [PATCH edk2-platforms] Silicon/Socionext/SynQuacer: add configurable eMMC support

[Leif Lindholm <leif.lindholm@linaro.org>]

On Tue, Jan 30, 2018 at 11:52:41AM +0000, Ard Biesheuvel wrote:
> >> >> +STATIC
> >> >> +EFI_STATUS
> >> >> +EFIAPI
> >> >> +SynQuacerSdMmcCapability (
> >> >> +  IN      EFI_HANDLE                      ControllerHandle,
> >> >> +  IN      UINT8                           Slot,
> >> >> +  IN  OUT VOID                            *SdMmcHcSlotCapability
> >> >> +  )
> >> >> +{
> >> >> +  UINT64 Capability;
> >> >> +
> >> >> +  if (ControllerHandle != mSdMmcControllerHandle || Slot != 0) {
> >> >
> >> > This test pattern repeats below, does it suggest a macro?
> >> >
> >>
> >> I don't see how that would clear things up tbh, and the pattern occurs
> >> only twice
> >>
> >> #define IS_OUR_QUIRKY_SDMMC_CONTROLLER(Handle, Slot) \
> >>   ((Handle) == mSdMmcControllerHandle && (Slot) == 0)
> >>
> >> if (!IS_OUR_QUIRKY_SDMMC_CONTROLLER(ControllerHandle, Slot) {
> >>   return EFI_SUCCESS;
> >> }
> >>
> >> I can change it if you want, or add a comment if the condition is not
> >> self-explanatory enough.
> >
> > It's just an awful lot of logical operations on a single line.
> > 'ControllerHandle != mSdMmcControllerHandle' is reasonably easy to
> > figure out, but '|| Slot != 0' looks a bit random there.
> >
> > A comment would be sufficient.
> >
> > Another option would be to reduce the number of logical operations by
> > two by doing
> >   if (ControllerHandle == mSdMmcControllerHandle && Slot == 0) {
> > and doing the body inside the if-statement.
> >
> > That's a bit uglier in the next function, but I would expect it
> > follows the paradigm of "handle most likely case first"?
> >
> 
> Actually, come to think of it, the slot number is completely
> redundant. The non-discoverable SDHCI controller we expose only
> implements a single slot, so something is terribly wrong if
> ControllerHandle == mSdMmcControllerHandle && Slot != 0.
> 
> So I will reduce the sequence to
> 
> if (ControllerHandle != mSdMmcControllerHandle) {
>   return EFI_SUCCESS;
> }
> 
> ASSERT (Slot == 0);
> 
> instead. Ok?

Sure, that works for me.
With that (in both places), and the indentation fix:
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>