From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 048FC2E06E4; Sat, 12 Sep 2026 12:55:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789217727; cv=none; b=SOrqaGgSsi7laym4JSb5s7qICxxk+tw/WFvbPHZ4b+nlSApETKQIRHVJRaE4Et7950+/BniBaDpD9nl4tZFc8UgMwiKObmDqk69XIRJej+P9ulhTpHnKSu6P0gdYVSqDt0q478ZmfTGFnF8sl3TMjEXraA64B7ATpI3pFcSyohA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789217727; c=relaxed/simple; bh=KlERh51soifQhOZ8tPHqpiQUVvsXFWGA/qwsxaRFiVM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=O2TADYLYb9cwP3RgiV0CNdexqDPBmOCnL5eSZFCqwv+NxmYFv9ch/DRcM8iqI90DEn1cCuLzQd7az/DjI9fZmvUryCfDGsnd54ugpOAgghpZXaiKgpg+3lsvuyOHmPV07NdcjNniLIdA092IYeCvSIDd8JbjbFpX46axDHv22bI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=O67IXTpr; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="O67IXTpr" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B22571F000FF; Sat, 12 Sep 2026 12:55:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789217725; bh=diYm1yDAfLXtsSGKfo1e15W+ZGuELSIYq5oHsYMcmeQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=O67IXTprrbJq7jTO3n3dm0+WX3rzC0LOUZ5iPCBGgrHWTiYzRYeV8HgTV+C1xdwP8 3BHpm4vvyx6uvN/rZ1kn34Nu1pqFcnIznmpVlMoc9pZjNF9UHvaqlDztutx8EaNcXE cYNoMxfiib6iX9exJK5X/nHF+lLErIgRum53W+GA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Nikhil Gautam , Jonathan Cameron , Sasha Levin Subject: [PATCH 6.12 0998/1376] iio: light: gp2ap002: Fix unbalanced runtime PM on repeated event writes Date: Sat, 12 Sep 2026 08:57:04 +0200 Message-ID: <20260912065629.807620863@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065607.535295758@linuxfoundation.org> References: <20260912065607.535295758@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nikhil Gautam [ Upstream commit 579c049b4cb6fc72ce2c505fc5334540be0efcd3 ] The IIO core does not filter duplicate writes to the event enable attribute, so writing the same value twice invokes write_event_config() twice. Enabling twice leaks a runtime PM reference, preventing the device from ever suspending again; disabling twice underflows the usage count and triggers a "Runtime PM usage count underflow" warning. Bail out early when the requested state matches the current state. While at it, switch to pm_runtime_resume_and_get() so a failed resume is propagated to userspace instead of silently marking the event enabled. Fixes: 97d642e23037c ("iio: light: Add a driver for Sharp GP2AP002x00F") Signed-off-by: Nikhil Gautam Signed-off-by: Jonathan Cameron Signed-off-by: Sasha Levin --- drivers/iio/light/gp2ap002.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/iio/light/gp2ap002.c b/drivers/iio/light/gp2ap002.c index be31505a87fa0..d82a4c93c9d16 100644 --- a/drivers/iio/light/gp2ap002.c +++ b/drivers/iio/light/gp2ap002.c @@ -343,6 +343,10 @@ static int gp2ap002_write_event_config(struct iio_dev *indio_dev, int state) { struct gp2ap002 *gp2ap002 = iio_priv(indio_dev); + int ret; + + if (state == gp2ap002->enabled) + return 0; if (state) { /* @@ -350,14 +354,17 @@ static int gp2ap002_write_event_config(struct iio_dev *indio_dev, * already) and reintialize the sensor by using runtime_pm * callbacks. */ - pm_runtime_get_sync(gp2ap002->dev); - gp2ap002->enabled = true; + ret = pm_runtime_resume_and_get(gp2ap002->dev); + if (ret) + return ret; + } else { pm_runtime_mark_last_busy(gp2ap002->dev); pm_runtime_put_autosuspend(gp2ap002->dev); - gp2ap002->enabled = false; } + gp2ap002->enabled = state; + return 0; } -- 2.53.0