Re: [PATCH] spi: Setup the master controller driver before setting the chipselect

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From	"Franklin S Cooper Jr." <fcooper@ti.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH] spi: Setup the master controller driver before setting the chipselect
Date	Fri, 16 Oct 2015 16:30:02 +0200
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On 10/16/2015 05:28 AM, Mark Brown wrote:
> On Thu, Oct 15, 2015 at 03:51:45PM -0500, Franklin S Cooper Jr wrote:
>> Some devices depend on the master controller driver setup function being
>> called before calling any chipselect functions.
>>
>> Insure that this is done otherwise uninitialized structures may be
>> accessed causing a kernel panic.
> I think this is a sensible change but can we please have a better
> changelog - why is this the best thing to do rather than fixing the
> driver to not crash?  There are a bunch of good reasons to do the master
> setup before asserting chip select but a driver crashing isn't one of
> them, it's not clear that this isn't a bug in the driver.
Mark,
Makes sense. How about something like this?

SPI controllers may need to be properly setup before chip selects
can be used. Therefore, wait until the spi controller has a chance
to perform their setup procedure before trying to use the chip
select.

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Thread

[PATCH] spi: Setup the master controller driver before setting the chipselect Franklin S Cooper Jr <fcooper@ti.com> - 2015-10-15 23:00 +0200
  Re: [PATCH] spi: Setup the master controller driver before setting  the chipselect Mark Brown <broonie@kernel.org> - 2015-10-16 12:30 +0200
    Re: [PATCH] spi: Setup the master controller driver before setting  the chipselect "Franklin S Cooper Jr." <fcooper@ti.com> - 2015-10-16 16:30 +0200
      Re: [PATCH] spi: Setup the master controller driver before setting  the chipselect "Franklin S Cooper Jr." <fcooper@ti.com> - 2015-10-16 16:50 +0200
      Re: [PATCH] spi: Setup the master controller driver before setting  the chipselect Mark Brown <broonie@kernel.org> - 2015-10-16 16:50 +0200

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