Re: [PATCH] PM / OPP: Initialize regulator pointer to an error value

From	Mark Brown <broonie@kernel.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH] PM / OPP: Initialize regulator pointer to an error value
Date	2016-02-16 03:00 +0100
Message-ID	<r2D5M-Rv-9@gated-at.bofh.it> (permalink)
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On Tue, Feb 16, 2016 at 06:30:59AM +0530, Viresh Kumar wrote:

> - And so I left the regulator pointer to NULL in OPP core.
> - But then I realized that its not safe to call many regulator core
>   APIs with NULL regulator, as those caused the crashes reported by
>   multiple people now.
> - clk APIs guarantee that they return early when NULL clk is passed to
>   them.
> - Do we need to do the same for regulator core as well ?

No, NULL is explicitly not something you can substitute in,
essentially all the users are just not bothering to implement error
checking and we don't want to encourage that.  The set of use cases
where we legitimately have optional supplies is very small, much smaller
than clocks, because it makes the electrical engineering a lot harder.

Thread

[PATCH] PM / OPP: Initialize regulator pointer to an error value Viresh Kumar <viresh.kumar@linaro.org> - 2016-02-15 17:30 +0100
  Re: [PATCH] PM / OPP: Initialize regulator pointer to an error value Viresh Kumar <viresh.kumar@linaro.org> - 2016-02-15 17:50 +0100
  Re: [PATCH] PM / OPP: Initialize regulator pointer to an error value Jon Hunter <jonathanh@nvidia.com> - 2016-02-15 17:50 +0100
  Re: [PATCH] PM / OPP: Initialize regulator pointer to an error value Arnd Bergmann <arnd@arndb.de> - 2016-02-15 21:40 +0100
    Re: [PATCH] PM / OPP: Initialize regulator pointer to an error value "Rafael J. Wysocki" <rafael@kernel.org> - 2016-02-15 22:20 +0100
      Re: [PATCH] PM / OPP: Initialize regulator pointer to an error value Viresh Kumar <viresh.kumar@linaro.org> - 2016-02-16 01:50 +0100
        Re: [PATCH] PM / OPP: Initialize regulator pointer to an error value "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2016-02-16 01:50 +0100
    Re: [PATCH] PM / OPP: Initialize regulator pointer to an error value Viresh Kumar <viresh.kumar@linaro.org> - 2016-02-16 02:10 +0100
      Re: [PATCH] PM / OPP: Initialize regulator pointer to an error value Mark Brown <broonie@kernel.org> - 2016-02-16 03:00 +0100
        Re: [PATCH] PM / OPP: Initialize regulator pointer to an error value Arnd Bergmann <arnd@arndb.de> - 2016-02-16 10:20 +0100
          Re: [PATCH] PM / OPP: Initialize regulator pointer to an error value Mark Brown <broonie@kernel.org> - 2016-02-16 14:20 +0100
            Re: [PATCH] PM / OPP: Initialize regulator pointer to an error value Arnd Bergmann <arnd@arndb.de> - 2016-02-16 16:20 +0100
              Re: [PATCH] PM / OPP: Initialize regulator pointer to an error value Mark Brown <broonie@kernel.org> - 2016-02-16 18:00 +0100

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