linux-kernel - Re: [PATCH v2 00/11] pwm: Add support for PWM Capture

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 6 Jun 2016 16:32:31 +0100
From:	Lee Jones <lee.jones@...aro.org>
To:	Boris Brezillon <boris.brezillon@...e-electrons.com>
Cc:	linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
	linux-pwm@...r.kernel.org, kernel@...inux.com,
	ajitpal.singh@...com, thierry.reding@...il.com,
	maxime.coquelin@...com
Subject: Re: [PATCH v2 00/11] pwm: Add support for PWM Capture

On Fri, 29 Apr 2016, Boris Brezillon wrote:

> Hi Lee,
> 
> On Fri, 22 Apr 2016 11:18:04 +0100
> Lee Jones <lee.jones@...aro.org> wrote:
> 
> > The first part of this set extends the current PWM API to allow external
> > code to request a PWM Capture.  Subsequent patches then make use of the
> > new API by providing a userspace offering via /sysfs.  The final part of
> > the set supplies PWM Capture functionality into the already existing STi
> > PWM driver.
> 
> Is there a reason you decided to not put this driver in IIO? IMHO, it
> would be more appropriate to make your PWM device an MFD that can either
> bind to the PWM or the capture driver.
> And BTW, IIO already has a sysfs interface (you may have to extend the
> API to support your type of capture though).

Multi-Function Device drivers can only be justified if the IP
contained does not and can not live in a single subsystem.  The IP
which controls both PWM-in and PWM-out in this device is the same.  I
can't fathom a sane reason why you would wish to separate this
functionality over multiple subsystems.

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog