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[82.37.195.13]) by smtp.gmail.com with ESMTPSA id t16-20020a5d49d0000000b0031c5b380291sm14405871wrs.110.2023.09.26.04.11.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 26 Sep 2023 04:11:39 -0700 (PDT) Date: Tue, 26 Sep 2023 12:11:37 +0100 From: Daniel Thompson To: Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= Cc: Lee Jones , Jingoo Han , Thierry Reding , Helge Deller , linux-pwm@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, kernel@pengutronix.de, Aisheng Dong , Aisheng Dong Subject: Re: [PATCH v2] backlight: pwm_bl: Disable PWM on shutdown and suspend Message-ID: <20230926111137.GA4356@aspen.lan> References: <20230926084612.2074692-1-u.kleine-koenig@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20230926084612.2074692-1-u.kleine-koenig@pengutronix.de> Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@vger.kernel.org On Tue, Sep 26, 2023 at 10:46:12AM +0200, Uwe Kleine-König wrote: > Since commit 00e7e698bff1 ("backlight: pwm_bl: Configure pwm only once > per backlight toggle") calling pwm_backlight_power_off() doesn't disable > the PWM any more. However this is necessary to suspend because PWM > drivers usually refuse to suspend if they are still enabled. > > Also adapt shutdown to disable the PWM for similar reasons. > > Fixes: 00e7e698bff1 ("backlight: pwm_bl: Configure pwm only once per backlight toggle") > Reported-by: Aisheng Dong > Tested-by: Aisheng Dong > Signed-off-by: Uwe Kleine-König Changes proposed look good (and the comment about badly designed boards going to HiZ state we super helpful). Only thing from my is why there is no attempt to disable the PWM from the .remove_new() callback. Daniel. 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[82.37.195.13]) by smtp.gmail.com with ESMTPSA id t16-20020a5d49d0000000b0031c5b380291sm14405871wrs.110.2023.09.26.04.11.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 26 Sep 2023 04:11:39 -0700 (PDT) Date: Tue, 26 Sep 2023 12:11:37 +0100 From: Daniel Thompson To: Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= Subject: Re: [PATCH v2] backlight: pwm_bl: Disable PWM on shutdown and suspend Message-ID: <20230926111137.GA4356@aspen.lan> References: <20230926084612.2074692-1-u.kleine-koenig@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20230926084612.2074692-1-u.kleine-koenig@pengutronix.de> X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Aisheng Dong , linux-pwm@vger.kernel.org, linux-fbdev@vger.kernel.org, Jingoo Han , Helge Deller , Lee Jones , dri-devel@lists.freedesktop.org, Aisheng Dong , Thierry Reding , kernel@pengutronix.de Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Tue, Sep 26, 2023 at 10:46:12AM +0200, Uwe Kleine-König wrote: > Since commit 00e7e698bff1 ("backlight: pwm_bl: Configure pwm only once > per backlight toggle") calling pwm_backlight_power_off() doesn't disable > the PWM any more. However this is necessary to suspend because PWM > drivers usually refuse to suspend if they are still enabled. > > Also adapt shutdown to disable the PWM for similar reasons. > > Fixes: 00e7e698bff1 ("backlight: pwm_bl: Configure pwm only once per backlight toggle") > Reported-by: Aisheng Dong > Tested-by: Aisheng Dong > Signed-off-by: Uwe Kleine-König Changes proposed look good (and the comment about badly designed boards going to HiZ state we super helpful). Only thing from my is why there is no attempt to disable the PWM from the .remove_new() callback. Daniel.