RE: [PATCH 1/7] ASoC: amd: No need PCI-MSI interrupts

From: Deucher, Alexander
Date: Thu Oct 17 2019 - 09:57:09 EST


> -----Original Message-----
> From: RAVULAPATI, VISHNU VARDHAN RAO
> <Vishnuvardhanrao.Ravulapati@xxxxxxx>
> Sent: Thursday, October 17, 2019 5:33 AM
> To: Mark Brown <broonie@xxxxxxxxxx>; Deucher, Alexander
> <Alexander.Deucher@xxxxxxx>
> Cc: RAVULAPATI, VISHNU VARDHAN RAO
> <Vishnuvardhanrao.Ravulapati@xxxxxxx>; Liam Girdwood
> <lgirdwood@xxxxxxxxx>; Jaroslav Kysela <perex@xxxxxxxx>; Takashi Iwai
> <tiwai@xxxxxxxx>; Mukunda, Vijendar <Vijendar.Mukunda@xxxxxxx>;
> Maruthi Srinivas Bayyavarapu <Maruthi.Bayyavarapu@xxxxxxx>; Colin Ian
> King <colin.king@xxxxxxxxxxxxx>; Dan Carpenter
> <dan.carpenter@xxxxxxxxxx>; moderated list:SOUND - SOC LAYER /
> DYNAMIC AUDIO POWER MANAGEM... <alsa-devel@xxxxxxxxxxxxxxxx>; open
> list <linux-kernel@xxxxxxxxxxxxxxx>
> Subject: Re: [PATCH 1/7] ASoC: amd: No need PCI-MSI interrupts
>
>
>
> On 11/10/19 3:03 AM, vishnu wrote:
> > Hi,
> > Please find my inline comments.
> >
> > Thanks,
> > Vishnu
> >
> > On 01/10/19 10:59 PM, Mark Brown wrote:
> >> On Tue, Oct 01, 2019 at 05:23:43PM +0000, Deucher, Alexander wrote:
> >>
> >>>> ACP-PCI controller driver does not depends msi interrupts.
> >>>> So removed msi related pci functions which have no use and does not
> >>>> impact on existing functionality.
> >>
> >>> In general, however, aren't MSIs preferred to legacy interrupts?
> >>
> >> As I understand it.  Or at the very least I'm not aware of any
> >> situation where they're harmful.  It'd be good to have a clear
> >> explanation of why we're removing the support.
> >
> > Actually our device is audio device and it does not depends on MSI`s.
> > So we thought to remove it as it has no purpose or meaning to have
> > this code in our audio based ACP-PCI driver.
> >
> >>> Doesn't the driver have to opt into MSI support?  As such, won't
> >>> removing this code effectively disable MSI support?
> >>
> >> Yes.
> >
> >
>
> Hi Mark,
>
> Any updates on this patch.

You are removing functionality from the driver with no rational as to why it's necessary. What's the point of this patch? Does it fix a particular issue? If not, I suggest just dropping it. The hw supports MSIs, why not use them?

Alex