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Subject: Re: [PATCH] serdev: Restore serdev_device_write_buf for atomic
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To: Johan Hovold <johan@kernel.org>, Rob Herring <robh@kernel.org>
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From: Stefan Wahren <stefan.wahren@i2se.com>
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Date: Thu, 4 May 2017 18:22:31 +0200
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Am 02.05.2017 um 15:18 schrieb Johan Hovold:
> On Tue, May 02, 2017 at 07:41:34AM -0500, Rob Herring wrote:
>> On Tue, May 2, 2017 at 4:06 AM, Johan Hovold <johan@kernel.org> wrote:
>>> On Fri, Apr 28, 2017 at 01:47:21PM +0200, Stefan Wahren wrote:
>>>> Starting with commit 6fe729c4bdae ("serdev: Add serdev_device_write
>>>> subroutine") the function serdev_device_write_buf cannot be used in
>>>> atomic context anymore (mutex_lock is sleeping). So restore the old
>>>> behavior.
>>> Yeah, preventing use in atomic context seems unnecessary, although any
>>> clients writing must now deal with serialisation themselves (as before,
>>> and as they should).
>> We could just remove the mutex for serdev_device_write and always make
>> the client responsible for serialization.
> That sounds reasonable.

So it's unwanted to have 2 write functions (non-atomic, atomic)?

Stefan