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Date:   Wed, 1 Nov 2023 12:47:17 +0200
From:   Mika Westerberg <mika.westerberg@linux.intel.com>
To:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc:     Chen Ni <nichen@iscas.ac.cn>, lee@kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] mfd: intel-lpss: Fix IRQ check
Message-ID: <20231101104717.GH17433@black.fi.intel.com>
References: <20231101062643.507983-1-nichen@iscas.ac.cn>
 <20231101070310.GF17433@black.fi.intel.com>
 <ZUIclOuVocLUUk7_@smile.fi.intel.com>
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On Wed, Nov 01, 2023 at 11:38:28AM +0200, Andy Shevchenko wrote:
> On Wed, Nov 01, 2023 at 09:03:10AM +0200, Mika Westerberg wrote:
> > On Wed, Nov 01, 2023 at 06:26:43AM +0000, Chen Ni wrote:
> > > platform_get_irq() returns a negative error code to indicating an
> > > error. So in intel_lpss_probe() the unset / erroneous IRQ should be
> > > returned as is.
> > > 
> > > Fixes: 4b45efe85263 ("mfd: Add support for Intel Sunrisepoint LPSS devices")
> 
> > There is no need for Fixes tag here.
> 
> I said that already in v1 :-)
> 
> ...
> 
> > > -	if (!info || !info->mem || info->irq <= 0)
> > > +	if (!info || !info->mem)
> > 
> > This check (info->irq <= 0) covers both "invalid" interrupt numbers
> > (that's the negative errno and 0 as no interrupt) so I don't see how
> > this change makes it any better and the changelog does not clarify it
> > either.
> 
> It makes sense. The IRQ here may not be 0. We should actually fix
> the PCI code to guarantee that (platform_get_irq() guarantees that
> in platform driver).

Yeah but I mean the check above handles any "invalid" interrupt number
just fine regardless. I don't see any point changing that.