linux-kernel - Re: [PATCH 2/4] pwm: omap-dmtimer: Fix pwm enabling sequence

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Message-ID: <20200224084956.wwsnf2y24ragg3vf@pengutronix.de>
Date:   Mon, 24 Feb 2020 09:49:56 +0100
From:   Uwe Kleine-König 
        <u.kleine-koenig@...gutronix.de>
To:     Lokesh Vutla <lokeshvutla@...com>
Cc:     Thierry Reding <thierry.reding@...il.com>,
        Tony Lindgren <tony@...mide.com>,
        Linux OMAP Mailing List <linux-omap@...r.kernel.org>,
        linux-kernel@...r.kernel.org, linux-pwm@...r.kernel.org,
        Sekhar Nori <nsekhar@...com>
Subject: Re: [PATCH 2/4] pwm: omap-dmtimer: Fix pwm enabling sequence

On Mon, Feb 24, 2020 at 10:51:33AM +0530, Lokesh Vutla wrote:
> To configure DM timer is pwm mode the following needs to be set in
> OMAP_TIMER_CTRL_REG using set_pwm callback:
> - Set toggle mode on PORTIMERPWM output pin
> - Set trigger on overflow and match on PORTIMERPWM output pin.
> - Set auto reload
> 
> This is a one time configuration and needs to be set before the start of
> the dm timer. But the current driver tries to set the same configuration
> for every period/duty cycle update, which is not needed. So move the pwm
> setup before enabling timer and do not update it in pwm_omap_dmtimer_config.

Is this change kind of moot with the conversion to .apply in the next
patch?

Best regards
Uwe

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