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Date:   Thu, 24 Jan 2019 11:44:35 +0100
From:   Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= 
        <u.kleine-koenig@pengutronix.de>
To:     Michal =?utf-8?B?Vm9rw6HEjQ==?= <michal.vokac@ysoft.com>
Cc:     Thierry Reding <thierry.reding@gmail.com>,
        Rob Herring <robh+dt@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
        "linux-pwm@vger.kernel.org" <linux-pwm@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Lukasz Majewski <l.majewski@majess.pl>,
        Fabio Estevam <fabio.estevam@nxp.com>,
        Lothar =?iso-8859-1?Q?Wa=DFmann?= <LW@karo-electronics.de>,
        Linus Walleij <linus.walleij@linaro.org>
Subject: Re: [RFC PATCH v3 2/2] pwm: imx: Configure output to GPIO in
 disabled state
Message-ID: <20190124104435.e6paqwcuz3hizwnv@pengutronix.de>
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On Thu, Jan 24, 2019 at 11:12:12AM +0100, Michal Vokáč wrote:
> On 24.1.2019 10:22, Uwe Kleine-König wrote:
> > I think it might be beneficial to allow (or require) that disable acts
> > immediately. But this is not how it used to be and in my discussion with
> > Thierry (IIRC) he required to complete the currently running period.
> 
> I am confused here. IFAIK it always used to be that:
> 
> 	pwm_apply_state(pwm, { .enabled = 0 });
> 
> immediately stops the PWM with:
> 
> 	writel(0, imx->mmio_base + MX3_PWMCR);
> 
> regardless of the period (for pwm-imx).

Then is is a bug since forever (well, or a fact that resulted from the
intended semantic not being documented and the driver author not caring
or knowing better).

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |