From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 97E35C433B4 for ; Tue, 6 Apr 2021 10:19:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7A7BF613C9 for ; Tue, 6 Apr 2021 10:19:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245050AbhDFKTy (ORCPT ); Tue, 6 Apr 2021 06:19:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44594 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242713AbhDFKTv (ORCPT ); Tue, 6 Apr 2021 06:19:51 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 86CBDC061756 for ; Tue, 6 Apr 2021 03:19:43 -0700 (PDT) Received: from ptx.hi.pengutronix.de ([2001:67c:670:100:1d::c0]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lTio6-0001jX-Hh; Tue, 06 Apr 2021 12:19:38 +0200 Received: from ukl by ptx.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1lTio4-0005iA-DU; Tue, 06 Apr 2021 12:19:36 +0200 Date: Tue, 6 Apr 2021 12:19:36 +0200 From: Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= To: Rex-BC Chen Cc: thierry.reding@gmail.com, lee.jones@linaro.org, matthias.bgg@gmail.com, linux-pwm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, Project_Global_Chrome_Upstream_Group@mediatek.com, Jitao Shi Subject: Re: [v3,PATCH 2/3] pwm: mtk_disp: convert the driver to atomic API Message-ID: <20210406101936.uscvtvrd6opm5pgf@pengutronix.de> References: <1617703062-4251-1-git-send-email-rex-bc.chen@mediatek.com> <1617703062-4251-3-git-send-email-rex-bc.chen@mediatek.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="qrbjywyivatj7v7m" Content-Disposition: inline In-Reply-To: <1617703062-4251-3-git-send-email-rex-bc.chen@mediatek.com> X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::c0 X-SA-Exim-Mail-From: ukl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --qrbjywyivatj7v7m Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hello, On Tue, Apr 06, 2021 at 05:57:41PM +0800, Rex-BC Chen wrote: > @@ -84,33 +86,47 @@ static int mtk_disp_pwm_config(struct pwm_chip *chip,= struct pwm_device *pwm, > * period =3D (PWM_CLK_RATE * period_ns) / (10^9 * (clk_div + 1)) - 1 > * high_width =3D (PWM_CLK_RATE * duty_ns) / (10^9 * (clk_div + 1)) > */ > + if (!mdp->enabled) { > + err =3D clk_prepare_enable(mdp->clk_main); > + if (err < 0) { > + dev_err(chip->dev, "Can't enable mdp->clk_main: %d\n", > + err); Please use %pe, as this yields better readable error messages. Also it might be sensible to first use the fact that (without patch 1 =66rom this series) the clocks are always on and then rework the clk usage in a separate patch. > + return err; > + } > + err =3D clk_prepare_enable(mdp->clk_mm); > + if (err < 0) { > + dev_err(chip->dev, "Can't enable mdp->clk_mm: %d\n", > + err); > + clk_disable_unprepare(mdp->clk_main); > + return err; > + } > + } > rate =3D clk_get_rate(mdp->clk_main); > - clk_div =3D div_u64(rate * period_ns, NSEC_PER_SEC) >> > + clk_div =3D div_u64(rate * state->period, NSEC_PER_SEC) >> > PWM_PERIOD_BIT_WIDTH; rate * state->period might overflow, it would be great if this could be catched. (But I don't consider this a stopper for this series.) > - if (clk_div > PWM_CLKDIV_MAX) > + if (clk_div > PWM_CLKDIV_MAX) { > + dev_err(chip->dev, "clock rate is too high: rate =3D %d Hz\n", > + rate); rate is an u64, %d isn't the right format for it. Doesn't this result in a compiler warning? > + clk_disable_unprepare(mdp->clk_mm); > + clk_disable_unprepare(mdp->clk_main); > return -EINVAL; > - > + } > div =3D NSEC_PER_SEC * (clk_div + 1); > - period =3D div64_u64(rate * period_ns, div); > + period =3D div64_u64(rate * state->period, div); > if (period > 0) > period--; > =20 > - high_width =3D div64_u64(rate * duty_ns, div); > + high_width =3D div64_u64(rate * state->duty_cycle, div); > value =3D period | (high_width << PWM_HIGH_WIDTH_SHIFT); > - > - err =3D clk_enable(mdp->clk_main); > - if (err < 0) > - return err; > - > - err =3D clk_enable(mdp->clk_mm); > - if (err < 0) { > - clk_disable(mdp->clk_main); > - return err; > - } > + polarity =3D 0; > + if (state->polarity =3D=3D PWM_POLARITY_INVERSED) > + polarity =3D PWM_POLARITY; I'm unsure if support for polarity should be added en passant in this patch. Maybe it would be clearer to add is separately. > mtk_disp_pwm_update_bits(mdp, mdp->data->con0, > PWM_CLKDIV_MASK, > clk_div << PWM_CLKDIV_SHIFT); > + mtk_disp_pwm_update_bits(mdp, mdp->data->con0, > + PWM_POLARITY, polarity); > mtk_disp_pwm_update_bits(mdp, mdp->data->con1, > PWM_PERIOD_MASK | PWM_HIGH_WIDTH_MASK, > value); Best regards Uwe --=20 Pengutronix e.K. | Uwe Kleine-K=F6nig | Industrial Linux Solutions | https://www.pengutronix.de/ | --qrbjywyivatj7v7m Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEfnIqFpAYrP8+dKQLwfwUeK3K7AkFAmBsNbUACgkQwfwUeK3K 7Ak7fQf/XD3gpjbGn1v9+zAGRP2jQEV4pv4oZAXPh3XfOHQWHauvAoPO81WdA0le NrkVkX3fWnhpWRWTs360jrPenNfhc95Svv8ARekaI7WKBo2o6e4wEXIPnv94hk5l usjD5WN7JFRcF9AMSfaOZyeKHf1hJ5KNWZvUfDxfljLgarAQNVCDsmnQ+HDQXMiy osb93UYzmq6X5sKVKkP6kKja9qkkjQVQ1ydfBZU1LL7sZSCsCNEU9BE/lCEP/Cug uIRF7rzxgYCgDYQmB9g1N5MBwg75Ur9ZeZC2YU3h1L26im6avqmf+v8xpfcT9WVF hqrXsXRAZZodkucekqCFb1LCLMBLXw== =ROQI -----END PGP SIGNATURE----- --qrbjywyivatj7v7m-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 117ADC433ED for ; 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bh=vymR2IvtxMBSxKfROj2riMJK2Vg0gFhKy8OTdUyjAAQ=; b=BcJB+4jHg08YVWJWotRlu9wTF eiWVkkrv0b684BvMValenGq/38Ia7HmmlECww0KqOUHp8GYc6493g31vCev6pmgDFMs/OEKmsbtDq RuosT3f42q3bXliEd/NSTBjb94RAQdWZ+U/1l0I5omicxJI61kYMGCDwfoE9p4VX9Tf8dGClgsngK ZfjgzbpW40cfwykncxySPH3TshsQbocwsFUboqm+RYGgTvABAqtafNimD8GxdYjrub/DRXjbdW/rK NmZYRAHph2musuyuVvPXFdG4mmhZEO1gpRbq8FAEUdDfjqgxwdo2z7F0jxjNKixtqWhgMq7SzJ1f5 vWLBigBng==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lTioO-0029CE-RT; Tue, 06 Apr 2021 10:19:56 +0000 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lTio7-00299g-Pv for linux-mediatek@lists.infradead.org; Tue, 06 Apr 2021 10:19:41 +0000 Received: from ptx.hi.pengutronix.de ([2001:67c:670:100:1d::c0]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lTio6-0001jX-Hh; Tue, 06 Apr 2021 12:19:38 +0200 Received: from ukl by ptx.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1lTio4-0005iA-DU; Tue, 06 Apr 2021 12:19:36 +0200 Date: Tue, 6 Apr 2021 12:19:36 +0200 From: Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= To: Rex-BC Chen Cc: thierry.reding@gmail.com, lee.jones@linaro.org, matthias.bgg@gmail.com, linux-pwm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, Project_Global_Chrome_Upstream_Group@mediatek.com, Jitao Shi Subject: Re: [v3,PATCH 2/3] pwm: mtk_disp: convert the driver to atomic API Message-ID: <20210406101936.uscvtvrd6opm5pgf@pengutronix.de> References: <1617703062-4251-1-git-send-email-rex-bc.chen@mediatek.com> <1617703062-4251-3-git-send-email-rex-bc.chen@mediatek.com> MIME-Version: 1.0 In-Reply-To: <1617703062-4251-3-git-send-email-rex-bc.chen@mediatek.com> X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::c0 X-SA-Exim-Mail-From: ukl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-mediatek@lists.infradead.org X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210406_111939_976446_81532C72 X-CRM114-Status: GOOD ( 20.43 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============7711284697343678640==" Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org --===============7711284697343678640== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="qrbjywyivatj7v7m" Content-Disposition: inline --qrbjywyivatj7v7m Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hello, On Tue, Apr 06, 2021 at 05:57:41PM +0800, Rex-BC Chen wrote: > @@ -84,33 +86,47 @@ static int mtk_disp_pwm_config(struct pwm_chip *chip,= struct pwm_device *pwm, > * period =3D (PWM_CLK_RATE * period_ns) / (10^9 * (clk_div + 1)) - 1 > * high_width =3D (PWM_CLK_RATE * duty_ns) / (10^9 * (clk_div + 1)) > */ > + if (!mdp->enabled) { > + err =3D clk_prepare_enable(mdp->clk_main); > + if (err < 0) { > + dev_err(chip->dev, "Can't enable mdp->clk_main: %d\n", > + err); Please use %pe, as this yields better readable error messages. Also it might be sensible to first use the fact that (without patch 1 =66rom this series) the clocks are always on and then rework the clk usage in a separate patch. > + return err; > + } > + err =3D clk_prepare_enable(mdp->clk_mm); > + if (err < 0) { > + dev_err(chip->dev, "Can't enable mdp->clk_mm: %d\n", > + err); > + clk_disable_unprepare(mdp->clk_main); > + return err; > + } > + } > rate =3D clk_get_rate(mdp->clk_main); > - clk_div =3D div_u64(rate * period_ns, NSEC_PER_SEC) >> > + clk_div =3D div_u64(rate * state->period, NSEC_PER_SEC) >> > PWM_PERIOD_BIT_WIDTH; rate * state->period might overflow, it would be great if this could be catched. (But I don't consider this a stopper for this series.) > - if (clk_div > PWM_CLKDIV_MAX) > + if (clk_div > PWM_CLKDIV_MAX) { > + dev_err(chip->dev, "clock rate is too high: rate =3D %d Hz\n", > + rate); rate is an u64, %d isn't the right format for it. Doesn't this result in a compiler warning? > + clk_disable_unprepare(mdp->clk_mm); > + clk_disable_unprepare(mdp->clk_main); > return -EINVAL; > - > + } > div =3D NSEC_PER_SEC * (clk_div + 1); > - period =3D div64_u64(rate * period_ns, div); > + period =3D div64_u64(rate * state->period, div); > if (period > 0) > period--; > =20 > - high_width =3D div64_u64(rate * duty_ns, div); > + high_width =3D div64_u64(rate * state->duty_cycle, div); > value =3D period | (high_width << PWM_HIGH_WIDTH_SHIFT); > - > - err =3D clk_enable(mdp->clk_main); > - if (err < 0) > - return err; > - > - err =3D clk_enable(mdp->clk_mm); > - if (err < 0) { > - clk_disable(mdp->clk_main); > - return err; > - } > + polarity =3D 0; > + if (state->polarity =3D=3D PWM_POLARITY_INVERSED) > + polarity =3D PWM_POLARITY; I'm unsure if support for polarity should be added en passant in this patch. Maybe it would be clearer to add is separately. > mtk_disp_pwm_update_bits(mdp, mdp->data->con0, > PWM_CLKDIV_MASK, > clk_div << PWM_CLKDIV_SHIFT); > + mtk_disp_pwm_update_bits(mdp, mdp->data->con0, > + PWM_POLARITY, polarity); > mtk_disp_pwm_update_bits(mdp, mdp->data->con1, > PWM_PERIOD_MASK | PWM_HIGH_WIDTH_MASK, > value); Best regards Uwe --=20 Pengutronix e.K. | Uwe Kleine-K=F6nig | Industrial Linux Solutions | https://www.pengutronix.de/ | --qrbjywyivatj7v7m Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEfnIqFpAYrP8+dKQLwfwUeK3K7AkFAmBsNbUACgkQwfwUeK3K 7Ak7fQf/XD3gpjbGn1v9+zAGRP2jQEV4pv4oZAXPh3XfOHQWHauvAoPO81WdA0le NrkVkX3fWnhpWRWTs360jrPenNfhc95Svv8ARekaI7WKBo2o6e4wEXIPnv94hk5l usjD5WN7JFRcF9AMSfaOZyeKHf1hJ5KNWZvUfDxfljLgarAQNVCDsmnQ+HDQXMiy osb93UYzmq6X5sKVKkP6kKja9qkkjQVQ1ydfBZU1LL7sZSCsCNEU9BE/lCEP/Cug uIRF7rzxgYCgDYQmB9g1N5MBwg75Ur9ZeZC2YU3h1L26im6avqmf+v8xpfcT9WVF hqrXsXRAZZodkucekqCFb1LCLMBLXw== =ROQI -----END PGP SIGNATURE----- --qrbjywyivatj7v7m-- --===============7711284697343678640== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Linux-mediatek mailing list Linux-mediatek@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-mediatek --===============7711284697343678640==-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B0C2CC433ED for ; Tue, 6 Apr 2021 10:21:35 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 44064613C4 for ; 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Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lTioF-0029Bb-GC; Tue, 06 Apr 2021 10:19:50 +0000 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lTio7-00299b-Kv for linux-arm-kernel@lists.infradead.org; Tue, 06 Apr 2021 10:19:41 +0000 Received: from ptx.hi.pengutronix.de ([2001:67c:670:100:1d::c0]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lTio6-0001jX-Hh; Tue, 06 Apr 2021 12:19:38 +0200 Received: from ukl by ptx.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1lTio4-0005iA-DU; Tue, 06 Apr 2021 12:19:36 +0200 Date: Tue, 6 Apr 2021 12:19:36 +0200 From: Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= To: Rex-BC Chen Cc: thierry.reding@gmail.com, lee.jones@linaro.org, matthias.bgg@gmail.com, linux-pwm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, Project_Global_Chrome_Upstream_Group@mediatek.com, Jitao Shi Subject: Re: [v3,PATCH 2/3] pwm: mtk_disp: convert the driver to atomic API Message-ID: <20210406101936.uscvtvrd6opm5pgf@pengutronix.de> References: <1617703062-4251-1-git-send-email-rex-bc.chen@mediatek.com> <1617703062-4251-3-git-send-email-rex-bc.chen@mediatek.com> MIME-Version: 1.0 In-Reply-To: <1617703062-4251-3-git-send-email-rex-bc.chen@mediatek.com> X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::c0 X-SA-Exim-Mail-From: ukl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-arm-kernel@lists.infradead.org X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210406_111939_878828_0F3CE64F X-CRM114-Status: GOOD ( 21.32 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============1142391802609057238==" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org --===============1142391802609057238== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="qrbjywyivatj7v7m" Content-Disposition: inline --qrbjywyivatj7v7m Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hello, On Tue, Apr 06, 2021 at 05:57:41PM +0800, Rex-BC Chen wrote: > @@ -84,33 +86,47 @@ static int mtk_disp_pwm_config(struct pwm_chip *chip,= struct pwm_device *pwm, > * period =3D (PWM_CLK_RATE * period_ns) / (10^9 * (clk_div + 1)) - 1 > * high_width =3D (PWM_CLK_RATE * duty_ns) / (10^9 * (clk_div + 1)) > */ > + if (!mdp->enabled) { > + err =3D clk_prepare_enable(mdp->clk_main); > + if (err < 0) { > + dev_err(chip->dev, "Can't enable mdp->clk_main: %d\n", > + err); Please use %pe, as this yields better readable error messages. Also it might be sensible to first use the fact that (without patch 1 =66rom this series) the clocks are always on and then rework the clk usage in a separate patch. > + return err; > + } > + err =3D clk_prepare_enable(mdp->clk_mm); > + if (err < 0) { > + dev_err(chip->dev, "Can't enable mdp->clk_mm: %d\n", > + err); > + clk_disable_unprepare(mdp->clk_main); > + return err; > + } > + } > rate =3D clk_get_rate(mdp->clk_main); > - clk_div =3D div_u64(rate * period_ns, NSEC_PER_SEC) >> > + clk_div =3D div_u64(rate * state->period, NSEC_PER_SEC) >> > PWM_PERIOD_BIT_WIDTH; rate * state->period might overflow, it would be great if this could be catched. (But I don't consider this a stopper for this series.) > - if (clk_div > PWM_CLKDIV_MAX) > + if (clk_div > PWM_CLKDIV_MAX) { > + dev_err(chip->dev, "clock rate is too high: rate =3D %d Hz\n", > + rate); rate is an u64, %d isn't the right format for it. Doesn't this result in a compiler warning? > + clk_disable_unprepare(mdp->clk_mm); > + clk_disable_unprepare(mdp->clk_main); > return -EINVAL; > - > + } > div =3D NSEC_PER_SEC * (clk_div + 1); > - period =3D div64_u64(rate * period_ns, div); > + period =3D div64_u64(rate * state->period, div); > if (period > 0) > period--; > =20 > - high_width =3D div64_u64(rate * duty_ns, div); > + high_width =3D div64_u64(rate * state->duty_cycle, div); > value =3D period | (high_width << PWM_HIGH_WIDTH_SHIFT); > - > - err =3D clk_enable(mdp->clk_main); > - if (err < 0) > - return err; > - > - err =3D clk_enable(mdp->clk_mm); > - if (err < 0) { > - clk_disable(mdp->clk_main); > - return err; > - } > + polarity =3D 0; > + if (state->polarity =3D=3D PWM_POLARITY_INVERSED) > + polarity =3D PWM_POLARITY; I'm unsure if support for polarity should be added en passant in this patch. Maybe it would be clearer to add is separately. > mtk_disp_pwm_update_bits(mdp, mdp->data->con0, > PWM_CLKDIV_MASK, > clk_div << PWM_CLKDIV_SHIFT); > + mtk_disp_pwm_update_bits(mdp, mdp->data->con0, > + PWM_POLARITY, polarity); > mtk_disp_pwm_update_bits(mdp, mdp->data->con1, > PWM_PERIOD_MASK | PWM_HIGH_WIDTH_MASK, > value); Best regards Uwe --=20 Pengutronix e.K. | Uwe Kleine-K=F6nig | Industrial Linux Solutions | https://www.pengutronix.de/ | --qrbjywyivatj7v7m Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEfnIqFpAYrP8+dKQLwfwUeK3K7AkFAmBsNbUACgkQwfwUeK3K 7Ak7fQf/XD3gpjbGn1v9+zAGRP2jQEV4pv4oZAXPh3XfOHQWHauvAoPO81WdA0le NrkVkX3fWnhpWRWTs360jrPenNfhc95Svv8ARekaI7WKBo2o6e4wEXIPnv94hk5l usjD5WN7JFRcF9AMSfaOZyeKHf1hJ5KNWZvUfDxfljLgarAQNVCDsmnQ+HDQXMiy osb93UYzmq6X5sKVKkP6kKja9qkkjQVQ1ydfBZU1LL7sZSCsCNEU9BE/lCEP/Cug uIRF7rzxgYCgDYQmB9g1N5MBwg75Ur9ZeZC2YU3h1L26im6avqmf+v8xpfcT9WVF hqrXsXRAZZodkucekqCFb1LCLMBLXw== =ROQI -----END PGP SIGNATURE----- --qrbjywyivatj7v7m-- --===============1142391802609057238== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel --===============1142391802609057238==--