From patchwork Sun Jul 24 17:10:56 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marek Vasut X-Patchwork-Id: 594176 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 6116AC43334 for ; Sun, 24 Jul 2022 17:11:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229469AbiGXRLO (ORCPT ); Sun, 24 Jul 2022 13:11:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52590 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229542AbiGXRLN (ORCPT ); Sun, 24 Jul 2022 13:11:13 -0400 Received: from phobos.denx.de (phobos.denx.de [85.214.62.61]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 958EF6568 for ; Sun, 24 Jul 2022 10:11:11 -0700 (PDT) Received: from tr.lan (ip-86-49-12-201.bb.vodafone.cz [86.49.12.201]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: marex@denx.de) by phobos.denx.de (Postfix) with ESMTPSA id BAE9A82119; Sun, 24 Jul 2022 19:11:08 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=denx.de; s=phobos-20191101; t=1658682669; bh=P0Zh7M6+7SwBXtsauIfRW+58aUCtGChVQAC86ph7HS4=; h=From:To:Cc:Subject:Date:From; b=ZHL/DZlmwDJYt4EmVigMi1gvlKXPSZgYR9laEbIbCeqAVtgTdOXf/3uqNsbRyFj8Y qpS8wfn0QTvOa5iENdf4LUtc/u95q1v0HE/nPXtI8GEDuHZF1Vp0ex/wZrQg07i8ER V7KbcbSLTa1i4l28LM5ZhQWSy+2bU4DFsYXgv6VJGtxSmKJynidHuY/Xq9KBudhoO9 A4nEZhBGdBn6K70UWELOYv8nZBL2ibQYOUl00e7L+dkliuDqVGpqlwscTMMgbVVmOH kMslcBJxGZco+wG7HSfMJFpS+IG9GCGYmJDkb7kWfhhgLtjdldqBN83Og/Zasld50U KvspFAec/fjAw== From: Marek Vasut To: linux-gpio@vger.kernel.org Cc: Marek Vasut , Bartosz Golaszewski , Linus Walleij , Loic Poulain , Marc Zyngier , NXP Linux Team , Peng Fan , Shawn Guo Subject: [PATCH v3 1/2] gpio: mxc: Protect GPIO irqchip RMW with bgpio spinlock Date: Sun, 24 Jul 2022 19:10:56 +0200 Message-Id: <20220724171057.18549-1-marex@denx.de> X-Mailer: git-send-email 2.35.1 MIME-Version: 1.0 X-Virus-Scanned: clamav-milter 0.103.6 at phobos.denx.de X-Virus-Status: Clean Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org The driver currently performs register read-modify-write without locking in its irqchip part, this could lead to a race condition when configuring interrupt mode setting. Add the missing bgpio spinlock lock/unlock around the register read-modify-write. Fixes: 07bd1a6cc7cbb ("MXC arch: Add gpio support for the whole platform") Signed-off-by: Marek Vasut Cc: Bartosz Golaszewski Cc: Linus Walleij Cc: Loic Poulain Cc: Marc Zyngier Cc: NXP Linux Team Cc: Peng Fan Cc: Shawn Guo --- V3: New patch --- drivers/gpio/gpio-mxc.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/gpio/gpio-mxc.c b/drivers/gpio/gpio-mxc.c index c871602fc5ba9..74a50139c9202 100644 --- a/drivers/gpio/gpio-mxc.c +++ b/drivers/gpio/gpio-mxc.c @@ -147,6 +147,7 @@ static int gpio_set_irq_type(struct irq_data *d, u32 type) { struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); struct mxc_gpio_port *port = gc->private; + unsigned long flags; u32 bit, val; u32 gpio_idx = d->hwirq; int edge; @@ -185,6 +186,8 @@ static int gpio_set_irq_type(struct irq_data *d, u32 type) return -EINVAL; } + spin_lock_irqsave(&port->gc.bgpio_lock, flags); + if (GPIO_EDGE_SEL >= 0) { val = readl(port->base + GPIO_EDGE_SEL); if (edge == GPIO_INT_BOTH_EDGES) @@ -204,15 +207,20 @@ static int gpio_set_irq_type(struct irq_data *d, u32 type) writel(1 << gpio_idx, port->base + GPIO_ISR); + spin_unlock_irqrestore(&port->gc.bgpio_lock, flags); + return 0; } static void mxc_flip_edge(struct mxc_gpio_port *port, u32 gpio) { void __iomem *reg = port->base; + unsigned long flags; u32 bit, val; int edge; + spin_lock_irqsave(&port->gc.bgpio_lock, flags); + reg += GPIO_ICR1 + ((gpio & 0x10) >> 2); /* lower or upper register */ bit = gpio & 0xf; val = readl(reg); @@ -230,6 +238,8 @@ static void mxc_flip_edge(struct mxc_gpio_port *port, u32 gpio) return; } writel(val | (edge << (bit << 1)), reg); + + spin_unlock_irqrestore(&port->gc.bgpio_lock, flags); } /* handle 32 interrupts in one status register */