From patchwork Sat Aug 24 05:50:31 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Torokhov X-Patchwork-Id: 13776336 Received: from mail-pl1-f169.google.com (mail-pl1-f169.google.com [209.85.214.169]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8AF031552E3; Sat, 24 Aug 2024 05:51:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.169 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724478664; cv=none; b=OWbzZY+DkGtCWuRWC3hWcNERKokY+TOZplsRnrg8YlDwFN+wrQxBsJgHN736pqcwERmc6Zxd/CCrXYeBkfx/569BxgjT8PjbD1kIY8s0hkR+42syRZ+MKZwHyocLCF3E+opAK5wulQZ02hteOdzg8V3wwk4HRmSp+gIko+cFW7o= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724478664; c=relaxed/simple; bh=jZc/ru8ieOguS6XNd3fDyKoJzxvdq03+pTPuWqE0FRQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Bkg1HzmjFbpv6P33VFGRtNFKoE8DAyagSthkEZCqpkKzUqYYHjNAbiILaZdDQmjzl3MKzH7A8/8e2msTBzgO+5wKac0hYAHo/xpjJMu4XgUgWrqPwuTArErT+wbhwrlugYV3FPWdp+GGTVmDp/GJHnKpY+bqWF9tFvzdbEyn/nI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=fd9ErRlh; arc=none smtp.client-ip=209.85.214.169 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="fd9ErRlh" Received: by mail-pl1-f169.google.com with SMTP id d9443c01a7336-2025031eb60so23383225ad.3; Fri, 23 Aug 2024 22:51:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1724478663; x=1725083463; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=ztZiHh+Ss+9GgllgOmhrzPgnRJ98j/KfpwosGaKcSPw=; b=fd9ErRlh/xQErQTBhJOU5UIq6eR8WGedIubVtjzYJ9DIi/CXfHYNTtUOkVi3sZcYT6 3i4/u7bTSUF+hE0iSGuCWtRzdPk6wZXvg5OliEDt3/5dsNHk2cTEmwA52ZsZaRgfyclw NOzFDNRqBcF8qDyzBa9PbGY4fuC1bZItFed7LxXcyO6jDypbfYO95u1uQL/K9b95uf63 SktIEtJ+V9C840iu0FWYfY1otYC5FNFN6km3TbC8MF8s+mYUrUMKO5qsyCkyGxwvfJUq MbUVNhpckFmLkcBI7Za2CgFu8wgqsIRgCgJHtD23q5Mr5eczHR9lbx0tYyHl92HoIWuR /TiQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1724478663; x=1725083463; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=ztZiHh+Ss+9GgllgOmhrzPgnRJ98j/KfpwosGaKcSPw=; b=SG2DDM+geo9w9T/3y+RQWdDJZlx8Nw3IZqkjVlo8diSNtdtxGSFRnf/sg5AvBr/ExB 0JyWnrinAZl2lv5QzKQK8Vn1d2WIuajBcnJEkPYW2f7V2boPW4/xOQXbDPd94rLw+1C7 lgsfe8ONca0FHjGNuQvScxTY/p2bSx3jbGcQN4CnhWw0kIWOl4ieE4nVoDLkcjV7b/Wk 9mAlZE+3CKfd5pUOAU0JB7JmJ91DMWA1v120RrEtj/YOT1A6lrIuN8SZ4uA2HKpUr+Zi DyK52qIHK7iplWSOznpzwTxCJGvccgkEXHk1MIGHKdbjMmFdCfZ87nYBkfW/+P+5xL01 Dgxg== X-Forwarded-Encrypted: i=1; AJvYcCWV2snsMaJCOpu2LGyAidlXaT5ZOPxpEbzcTCM4khYVI5cSfGSWJSfY0g7PYryasWhtYfO9tww7uFoLHk6G@vger.kernel.org, AJvYcCXB43w1n4AZcrL3T54cVG/39/q7HmdNZGjBAcvRQvE05CFY36pwSDAz28fsO0o1imxCifaozrj4KKVF7Q==@vger.kernel.org X-Gm-Message-State: AOJu0YwIlg0Ta5ZjmVdIs4RBtEXWecd6r6YrhOKjcgSo1Pg86BkbnJ77 h0X4b1WMX88m7oj/LduY4tBkgFswYMAii9asviHLhlc1mJA+kQ0B X-Google-Smtp-Source: AGHT+IGot0lQRgzGokFPzNf71FPRlrLtsMrbJ1ij7h8spkWMrpcdahIR65WkFEWR2vsBXXI5LaaCFw== X-Received: by 2002:a17:903:188:b0:1fc:86cc:4254 with SMTP id d9443c01a7336-2039e4b37c1mr44644235ad.33.1724478662530; Fri, 23 Aug 2024 22:51:02 -0700 (PDT) Received: from dtor-ws.sjc.corp.google.com ([2620:15c:9d:2:75c:5a5a:d7dc:18f6]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-20395ef904dsm23398615ad.31.2024.08.23.22.51.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 23 Aug 2024 22:51:02 -0700 (PDT) From: Dmitry Torokhov To: =?utf-8?q?Heiko_St=C3=BCbner?= , linux-input@vger.kernel.org Cc: Andreas Kemnade , linux-kernel@vger.kernel.org Subject: [PATCH 07/18] Input: zforce_ts - ensure that pm_stay_awake() and pm_relax() are balanced Date: Fri, 23 Aug 2024 22:50:31 -0700 Message-ID: <20240824055047.1706392-8-dmitry.torokhov@gmail.com> X-Mailer: git-send-email 2.46.0.295.g3b9ea8a38a-goog In-Reply-To: <20240824055047.1706392-1-dmitry.torokhov@gmail.com> References: <20240824055047.1706392-1-dmitry.torokhov@gmail.com> Precedence: bulk X-Mailing-List: linux-input@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 There is a small chance that ts->suspending flag may change while the interrupt handler is running. To make sure call to pm_relax() is not skipped on accident use a temporary to hold the original value at the beginning of interrupt. Use READ_ONCE() so that the value is actually fetched at the right time. Signed-off-by: Dmitry Torokhov --- drivers/input/touchscreen/zforce_ts.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/drivers/input/touchscreen/zforce_ts.c b/drivers/input/touchscreen/zforce_ts.c index afeafa589928..004ef728fb90 100644 --- a/drivers/input/touchscreen/zforce_ts.c +++ b/drivers/input/touchscreen/zforce_ts.c @@ -454,6 +454,7 @@ static irqreturn_t zforce_irq_thread(int irq, void *dev_id) int ret; u8 payload_buffer[FRAME_MAXSIZE]; u8 *payload; + bool suspending; /* * When still suspended, return. @@ -467,7 +468,8 @@ static irqreturn_t zforce_irq_thread(int irq, void *dev_id) dev_dbg(&client->dev, "handling interrupt\n"); /* Don't emit wakeup events from commands run by zforce_suspend */ - if (!ts->suspending && device_may_wakeup(&client->dev)) + suspending = READ_ONCE(ts->suspending); + if (!suspending && device_may_wakeup(&client->dev)) pm_stay_awake(&client->dev); /* @@ -495,7 +497,7 @@ static irqreturn_t zforce_irq_thread(int irq, void *dev_id) * Always report touch-events received while * suspending, when being a wakeup source */ - if (ts->suspending && device_may_wakeup(&client->dev)) + if (suspending && device_may_wakeup(&client->dev)) pm_wakeup_event(&client->dev, 500); zforce_touch_event(ts, &payload[RESPONSE_DATA]); break; @@ -548,7 +550,7 @@ static irqreturn_t zforce_irq_thread(int irq, void *dev_id) } } while (gpiod_get_value_cansleep(ts->gpio_int)); - if (!ts->suspending && device_may_wakeup(&client->dev)) + if (!suspending && device_may_wakeup(&client->dev)) pm_relax(&client->dev); dev_dbg(&client->dev, "finished interrupt\n"); @@ -584,7 +586,9 @@ static int zforce_suspend(struct device *dev) int ret = 0; mutex_lock(&input->mutex); - ts->suspending = true; + + WRITE_ONCE(ts->suspending, true); + smp_mb(); /* * When configured as a wakeup source device should always wake @@ -615,7 +619,9 @@ static int zforce_suspend(struct device *dev) ts->suspended = true; unlock: - ts->suspending = false; + smp_mb(); + WRITE_ONCE(ts->suspending, false); + mutex_unlock(&input->mutex); return ret;