From patchwork Fri Sep 16 15:15:06 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= X-Patchwork-Id: 606885 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5750CECAAA1 for ; Fri, 16 Sep 2022 15:15:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230483AbiIPPPj (ORCPT ); Fri, 16 Sep 2022 11:15:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54634 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229714AbiIPPPi (ORCPT ); Fri, 16 Sep 2022 11:15:38 -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 6AC974B49D for ; Fri, 16 Sep 2022 08:15:37 -0700 (PDT) Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1oZD3p-0003yS-JO; Fri, 16 Sep 2022 17:15:21 +0200 Received: from [2a0a:edc0:0:900:1d::77] (helo=ptz.office.stw.pengutronix.de) by drehscheibe.grey.stw.pengutronix.de with esmtp (Exim 4.94.2) (envelope-from ) id 1oZD3l-0016t7-EM; Fri, 16 Sep 2022 17:15:15 +0200 Received: from ukl by ptz.office.stw.pengutronix.de with local (Exim 4.94.2) (envelope-from ) id 1oZD3i-001KHo-TK; Fri, 16 Sep 2022 17:15:14 +0200 From: =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= To: Thierry Reding Cc: linux-pwm@vger.kernel.org, kernel@pengutronix.de, Steven Rostedt , Ingo Molnar , Pavel Machek , Douglas Anderson , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Linus Walleij , Bartosz Golaszewski , linux-leds@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-gpio@vger.kernel.org Subject: [PATCH 3/3] pwm: Handle .get_state() failures Date: Fri, 16 Sep 2022 17:15:06 +0200 Message-Id: <20220916151506.298488-3-u.kleine-koenig@pengutronix.de> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220916151506.298488-1-u.kleine-koenig@pengutronix.de> References: <20220916151506.298488-1-u.kleine-koenig@pengutronix.de> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=1545; i=u.kleine-koenig@pengutronix.de; h=from:subject; bh=yRNfMNUl3EWYauPtdr8Q5dOzGtnTvg1riQcLCuuQwro=; b=owGbwMvMwMV48I9IxdpTbzgZT6slMSSrTPrubcN224Djq8gEu7yr52o0UwQV7R/Utndef8XX9eqM vVpYJ6MxCwMjF4OsmCJLXZGW2ASJNf/tSpZwwwxiZQKZwsDFKQAT2VnM/ldO1MlmZQ/n5hm5UtwfTH 8fCnMs39J9X7n78UVRDgvGxNL8i+28bXlJ89Lrje8ziYtWJX786VL0v0L10faISEar+B1fBTdJ2nse V4378K1D00X0w7SdZu/5yt7mrz+lbTjb7LtA4t25N4MOcj7imWo6sTeL61d6JeP07zMro5vZpRoX/w o0+388Nedof5/BrWcesx8u/mml27D0wSaOrSpOv+3+HKgRMtSUkGdMv6s4VU8gZ8om49sVpd0LnWRu 9+ke2XBHvU5Jku1O9q/SX4eeGjdXM822MOnmdI2z23gtZLHgXDnO/ZZsV0RzhL3i7h0OcO2+LxnG9Z lJsfD54uKICL5LOuLqttPttVwB X-Developer-Key: i=u.kleine-koenig@pengutronix.de; a=openpgp; fpr=0D2511F322BFAB1C1580266BE2DCDD9132669BD6 X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 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-leds@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-leds@vger.kernel.org This suppresses diagnosis for PWM_DEBUG routines and makes sure that pwm->state isn't modified in pwm_device_request() if .get_state() fails. Signed-off-by: Uwe Kleine-König --- drivers/pwm/core.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c index 381db04cfa00..421573590613 100644 --- a/drivers/pwm/core.c +++ b/drivers/pwm/core.c @@ -108,9 +108,14 @@ static int pwm_device_request(struct pwm_device *pwm, const char *label) } if (pwm->chip->ops->get_state) { - err = pwm->chip->ops->get_state(pwm->chip, pwm, &pwm->state); + struct pwm_state state; + + err = pwm->chip->ops->get_state(pwm->chip, pwm, &state); trace_pwm_get(pwm, &pwm->state, err); + if (!err) + pwm->state = state; + if (IS_ENABLED(CONFIG_PWM_DEBUG)) pwm->last = pwm->state; } @@ -459,6 +464,9 @@ static void pwm_apply_state_debug(struct pwm_device *pwm, err = chip->ops->get_state(chip, pwm, &s1); trace_pwm_get(pwm, &s1, err); + if (err) + /* If that failed there isn't much to debug */ + return; /* * The lowlevel driver either ignored .polarity (which is a bug) or as @@ -523,6 +531,8 @@ static void pwm_apply_state_debug(struct pwm_device *pwm, err = chip->ops->get_state(chip, pwm, last); trace_pwm_get(pwm, last, err); + if (err) + return; /* reapplication of the current state should give an exact match */ if (s1.enabled != last->enabled ||