[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [PATCH 02/13] ALSA: hda_intel: Use always-managed version of pcim_intx()
On Thu, 24 Oct 2024 10:02:59 +0200, Philipp Stanner wrote: > > On Wed, 2024-10-23 at 17:03 +0200, Takashi Iwai wrote: > > On Wed, 23 Oct 2024 15:50:09 +0200, > > Philipp Stanner wrote: > > > > > > On Tue, 2024-10-22 at 16:08 +0200, Takashi Iwai wrote: > > > > On Tue, 15 Oct 2024 20:51:12 +0200, > > > > Philipp Stanner wrote: > > > > > > > > > > pci_intx() is a hybrid function which can sometimes be managed > > > > > through > > > > > devres. To remove this hybrid nature from pci_intx(), it is > > > > > necessary to > > > > > port users to either an always-managed or a never-managed > > > > > version. > > > > > > > > > > hda_intel enables its PCI-Device with pcim_enable_device(). > > > > > Thus, > > > > > it needs > > > > > the always-managed version. > > > > > > > > > > Replace pci_intx() with pcim_intx(). > > > > > > > > > > Signed-off-by: Philipp Stanner <pstanner@xxxxxxxxxx> > > > > > --- > > > > > sound/pci/hda/hda_intel.c | 2 +- > > > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > > > > > diff --git a/sound/pci/hda/hda_intel.c > > > > > b/sound/pci/hda/hda_intel.c > > > > > index b4540c5cd2a6..b44ca7b6e54f 100644 > > > > > --- a/sound/pci/hda/hda_intel.c > > > > > +++ b/sound/pci/hda/hda_intel.c > > > > > @@ -786,7 +786,7 @@ static int azx_acquire_irq(struct azx > > > > > *chip, > > > > > int do_disconnect) > > > > > } > > > > > bus->irq = chip->pci->irq; > > > > > chip->card->sync_irq = bus->irq; > > > > > - pci_intx(chip->pci, !chip->msi); > > > > > + pcim_intx(chip->pci, !chip->msi); > > > > > return 0; > > > > > } > > > > > > > > > > > > > Hm, it's OK-ish to do this as it's practically same as what > > > > pci_intx() > > > > currently does. But, the current code can be a bit inconsistent > > > > about > > > > the original intx value. pcim_intx() always stores !enable to > > > > res->orig_intx unconditionally, and it means that the orig_intx > > > > value > > > > gets overridden at each time pcim_intx() gets called. > > > > > > Yes. > > > > > > > > > > > Meanwhile, HD-audio driver does release and re-acquire the > > > > interrupt > > > > after disabling MSI when something goes wrong, and pci_intx() > > > > call > > > > above is a part of that procedure. So, it can rewrite the > > > > res->orig_intx to another value by retry without MSI. And after > > > > the > > > > driver removal, it'll lead to another state. > > > > > > I'm not sure that I understand this paragraph completely. Still, > > > could > > > a solution for the driver on the long-term just be to use > > > pci_intx()? > > > > pci_intx() misses the restore of the original value, so it's no > > long-term solution, either. > > Sure that is missing – I was basically asking whether the driver could > live without that feature. > > Consider that point obsolete, see below > > > > > What I meant is that pcim_intx() blindly assumes the negative of the > > passed argument as the original state, which isn't always true. e.g. > > when the driver calls it twice with different values, a wrong value > > may be remembered. > > Ah, I see – thoguh the issue is when it's called several times with the > *same* value, isn't it? > > E.g. > > pcim_intx(pdev, 1); // 0 is remembered as the old value > pcim_intx(pdev, 1); // 0 is falsely remembered as the old value > > Also, it would seem that calling the function for the first time like > that: > > pcim_intx(pdev, 0); // old value: 1 > > is at least incorrect, because INTx should be 0 per default, shouldn't > it? Could then even be a 1st class bug, because INTx would end up being > enabled despite having been disabled all the time. Yeah, and the unexpected restore can happen even with a single call of pcim_intx(), if the driver calls it unnecessarily. > > That said, I thought of something like below. > > At first glance that looks like a good idea to me, thanks for working > this out! > > IMO you can submit that as a patch so we can discuss it separately. Sure, I'm going to submit later. thanks, Takashi
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