linux-kernel - Re: [PATCH v2 04/15] spi: Replace open coded spi_controller_xfer

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Message-ID: <ZK02efTYxV3czigr@smile.fi.intel.com>
Date:   Tue, 11 Jul 2023 14:01:13 +0300
From:   Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To:     Mark Brown <broonie@...nel.org>
Cc:     Cristian Ciocaltea <cristian.ciocaltea@...labora.com>,
        Yang Yingliang <yangyingliang@...wei.com>,
        Amit Kumar Mahapatra via Alsa-devel 
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        Uwe Kleine-König 
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        Richard Cochran <richardcochran@...il.com>
Subject: Re: [PATCH v2 04/15] spi: Replace open coded
 spi_controller_xfer_timeout()

On Mon, Jul 10, 2023 at 06:30:32PM +0100, Mark Brown wrote:
> On Mon, Jul 10, 2023 at 06:49:21PM +0300, Andy Shevchenko wrote:
> 
> > Since the new spi_controller_xfer_timeout() helper appeared,
> > we may replace open coded variant in spi_transfer_wait().
> 
> > + * Assume speed to be 100 kHz if it's not defined at the time of invocation.
> > + *
> 
> You didn't mention this bit in the changelog, and I'm not 100% convinced
> it was the best idea in the first place.  It's going to result in some
> very big timeouts if it goes off, and we really should be doing
> validation much earlier in the process.

Okay, let's drop this change.

> > +	u32 speed_hz = xfer->speed_hz ?: 100000;
> 
> Not only the ternery operator, but the version without the second
> argument for extra clarity!

Elvis can be interpreted as "A _or_ B (if A is false/0)".
Some pieces related to SPI use Elvis already IIRC.

-- 
With Best Regards,
Andy Shevchenko