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Message-ID: <f3b6524f899f2775e630dee2ad1cc4c4c389b2fe.camel@intel.com>
Subject: Re: [PATCH] i2c: ismt: Remove useless DMA-32 fallback configuration
From:   Seth Heasley <seth.heasley@intel.com>
To:     Wolfram Sang <wsa@kernel.org>,
        Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc:     Neil Horman <nhorman@tuxdriver.com>, linux-kernel@vger.kernel.org,
        kernel-janitors@vger.kernel.org, linux-i2c@vger.kernel.org,
        seth.heasley@intel.com
Date:   Tue, 05 Apr 2022 14:13:04 -0700
In-Reply-To: <YgEtUT7Dhntmidxy@shikoro>
References: <853d9f9d746864435abf93dfc822fccac5b04f37.1641731339.git.christophe.jaillet@wanadoo.fr>
         <YgEtUT7Dhntmidxy@shikoro>
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On Mon, 2022-02-07 at 15:31 +0100, Wolfram Sang wrote:
> On Sun, Jan 09, 2022 at 01:29:45PM +0100, Christophe JAILLET wrote:
> > As stated in [1], dma_set_mask() with a 64-bit mask never fails if
> > dev->dma_mask is non-NULL.
> > So, if it fails, the 32 bits case will also fail for the same
> > reason.
> > 
> > 
> > Simplify code and remove some dead code accordingly.
> > 
> > [1]: https://lkml.org/lkml/2021/6/7/398
> > 
> > Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Seth Heasley <seth.heasley@intel.com>
> 
> Seth, Neil, do you agree?

Yes, I agree this change makes sense.

> 
> > ---
> >  drivers/i2c/busses/i2c-ismt.c | 7 ++-----
> >  1 file changed, 2 insertions(+), 5 deletions(-)
> > 
> > diff --git a/drivers/i2c/busses/i2c-ismt.c
> > b/drivers/i2c/busses/i2c-ismt.c
> > index f4820fd3dc13..951f3511afaa 100644
> > --- a/drivers/i2c/busses/i2c-ismt.c
> > +++ b/drivers/i2c/busses/i2c-ismt.c
> > @@ -920,11 +920,8 @@ ismt_probe(struct pci_dev *pdev, const struct
> > pci_device_id *id)
> >  
> >  	err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
> >  	if (err) {
> > -		err = dma_set_mask_and_coherent(&pdev->dev,
> > DMA_BIT_MASK(32));
> > -		if (err) {
> > -			dev_err(&pdev->dev, "dma_set_mask fail\n");
> > -			return -ENODEV;
> > -		}
> > +		dev_err(&pdev->dev, "dma_set_mask fail\n");
> > +		return -ENODEV;
> >  	}
> >  
> >  	err = ismt_dev_init(priv);
> > -- 
> > 2.32.0
> >