Re: [PATCH RFC] hwspinlock: Don't take software spinlock before hwspinlock

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From	Ohad Ben-Cohen <ohad@wizery.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH RFC] hwspinlock: Don't take software spinlock before hwspinlock
Date	Sat, 06 Jun 2015 05:30:02 +0200
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On Sat, Jun 6, 2015 at 2:50 AM, Jeffrey Hugo <jhugo@codeaurora.org> wrote:
> If you still wish to scope out a capability based alternative, would you
> please provide some details about how you envision it working?  An example
> of the API, how it would be used, future usecases that might be covered by
> it, etc.  That would give us specifics we can discuss and weigh the merits
> of.

How about:
- add a 'hwcaps' member to hwspinlock_device, and define single cap
called HWL_CAP_ALLOW_RAW
- add new 'hwcaps' parameter to hwspin_lock_register
- omap_hwspinlock.c will pass NULL, qcom_hwspinlock will pass HWL_CAP_ALLOW_RAW
- hwspin_lock_register will set hwcaps accordingly
- before a lock is taken in RAW mode, the capabilities are checked
- document everything nicely

Unless I'm missing something, it should take 5 minutes or less. For
reference, feel free to check out mmc_host's caps member and its
usage.

Thanks,
Ohad.
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Re: [PATCH RFC] hwspinlock: Don't take software spinlock before hwspinlock Jeffrey Hugo <jhugo@codeaurora.org> - 2015-06-06 02:00 +0200
  Re: [PATCH RFC] hwspinlock: Don't take software spinlock before hwspinlock Ohad Ben-Cohen <ohad@wizery.com> - 2015-06-06 05:30 +0200

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