From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BE906280327; Thu, 15 Jan 2026 17:19:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768497549; cv=none; b=g/HbkaHw7VPNOeM9dm74ecI3L5qMMJbEi843c7JAFi4ADFg8oj3rBte32lm702EOvo57q65nta7zy65j0Br8Saem2hIu1JNUWjtmN3Mm+URdRgBHFd561pKo7/A2/pnArCb4cUg0W0/RnX180/edLfV7Empwq0qoPdINQUQKw88= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768497549; c=relaxed/simple; bh=MfcfgBdtcu4SNoQCocHR0RrrXdb2l3hKB11ed7zeSV4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=uq6oYcogtz7Csj7usnqjvWrvqgH2dKVHpUQlVb+fpHHFLAwb+Zdn6YOQISMcFzzhuPSPW+cM1SVjJ0pUGkCCohlh23/C7ZIN92hjDW5ce7MjXyi++4lizLY9VoP7/CfPU26xpufg6A7DKnv6Dd6Sj42AUvqCc7sfD2/f9xlT8YY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=iKah0f+a; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="iKah0f+a" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4BA89C116D0; Thu, 15 Jan 2026 17:19:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1768497549; bh=MfcfgBdtcu4SNoQCocHR0RrrXdb2l3hKB11ed7zeSV4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iKah0f+aky68VUPYKzFWWqy/kX0jRGtDKOaT2+xmOtH4S91Hnz/BzPn7/3Zl+Zfpl elNGcouLSZ8dkMJlV2BtdrFr64J5AdHdTAvXc0WRDgnWdHojmWjZFcW0Bq1fayzZEX Q9GNYjuEjZ71qC5rYd4CKI5bdcRZ4hJCvxsPDmfE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= , Florian Fainelli , =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= , Sasha Levin Subject: [PATCH 5.15 120/554] pwm: bcm2835: Make sure the channel is enabled after pwm_request() Date: Thu, 15 Jan 2026 17:43:06 +0100 Message-ID: <20260115164250.593381494@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260115164246.225995385@linuxfoundation.org> References: <20260115164246.225995385@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Uwe Kleine-König [ Upstream commit cda323dbda76600bf9761970d58517648f0de67d ] The .free callback cleared among others the enable bit PWENx in the control register. When the PWM is requested later again this bit isn't restored but the core assumes the PWM is enabled and thus skips a request to configure the same state as before. To fix that don't touch the hardware configuration in .free(). For symmetry also drop .request() and configure the mode completely in .apply(). Fixes: e5a06dc5ac1f ("pwm: Add BCM2835 PWM driver") Signed-off-by: Uwe Kleine-König Reviewed-by: Florian Fainelli Link: https://patch.msgid.link/20251118174303.1761577-2-u.kleine-koenig@baylibre.com Signed-off-by: Uwe Kleine-König Signed-off-by: Sasha Levin --- drivers/pwm/pwm-bcm2835.c | 28 +++------------------------- 1 file changed, 3 insertions(+), 25 deletions(-) diff --git a/drivers/pwm/pwm-bcm2835.c b/drivers/pwm/pwm-bcm2835.c index 50b8594be31d8..4541d63d57c40 100644 --- a/drivers/pwm/pwm-bcm2835.c +++ b/drivers/pwm/pwm-bcm2835.c @@ -35,29 +35,6 @@ static inline struct bcm2835_pwm *to_bcm2835_pwm(struct pwm_chip *chip) return container_of(chip, struct bcm2835_pwm, chip); } -static int bcm2835_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm) -{ - struct bcm2835_pwm *pc = to_bcm2835_pwm(chip); - u32 value; - - value = readl(pc->base + PWM_CONTROL); - value &= ~(PWM_CONTROL_MASK << PWM_CONTROL_SHIFT(pwm->hwpwm)); - value |= (PWM_MODE << PWM_CONTROL_SHIFT(pwm->hwpwm)); - writel(value, pc->base + PWM_CONTROL); - - return 0; -} - -static void bcm2835_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) -{ - struct bcm2835_pwm *pc = to_bcm2835_pwm(chip); - u32 value; - - value = readl(pc->base + PWM_CONTROL); - value &= ~(PWM_CONTROL_MASK << PWM_CONTROL_SHIFT(pwm->hwpwm)); - writel(value, pc->base + PWM_CONTROL); -} - static int bcm2835_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, const struct pwm_state *state) { @@ -109,6 +86,9 @@ static int bcm2835_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, /* set polarity */ val = readl(pc->base + PWM_CONTROL); + val &= ~(PWM_CONTROL_MASK << PWM_CONTROL_SHIFT(pwm->hwpwm)); + val |= PWM_MODE << PWM_CONTROL_SHIFT(pwm->hwpwm); + if (state->polarity == PWM_POLARITY_NORMAL) val &= ~(PWM_POLARITY << PWM_CONTROL_SHIFT(pwm->hwpwm)); else @@ -126,8 +106,6 @@ static int bcm2835_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, } static const struct pwm_ops bcm2835_pwm_ops = { - .request = bcm2835_pwm_request, - .free = bcm2835_pwm_free, .apply = bcm2835_pwm_apply, .owner = THIS_MODULE, }; -- 2.51.0