From patchwork Thu Oct 13 21:59:45 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marek Vasut X-Patchwork-Id: 615151 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 6F3F9C433FE for ; Thu, 13 Oct 2022 22:00:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229619AbiJMWAH (ORCPT ); Thu, 13 Oct 2022 18:00:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41540 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229747AbiJMWAG (ORCPT ); Thu, 13 Oct 2022 18:00:06 -0400 Received: from phobos.denx.de (phobos.denx.de [85.214.62.61]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CA66D4661A for ; Thu, 13 Oct 2022 15:00:01 -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 52ECF84E34; Thu, 13 Oct 2022 23:59:59 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=denx.de; s=phobos-20191101; t=1665698399; bh=mcIH9vyGFAi5LgCNlhhGQvD0BUKmEvWs0m9iwaGiU6I=; h=From:To:Cc:Subject:Date:From; b=RvVbTjVL/+5sBrGwNHoEChDTJN7DkReFo+PmWmLExKeNfxzePPp3KNLdZkY2db/13 ArGmw37CO7p3RUYIwegvE+dsN9DxTndkQ6k3ZV4O4BS16HvXmV4SRnhxoHjZXiTyZQ pod7r5CpYxzE8bXCWYJ18fsi0fzXjnzq39OOerE1DI0AApUVqjOjdgMgSl2mDN9/b3 VYDmJFLcZfhEywGQU0VKhunRWH+paYle3NVVbXZbqWamcVVzlmSzmL5ipx/61SQjKV AqDmDhjM2oD4DLh0XmOtX4lvQNyl8x1ts6kgdOT9QygeqU+BHQLzV2Vhz6Tp5ij8gj wGun7JJbNRX6w== From: Marek Vasut To: linux-gpio@vger.kernel.org Cc: Marek Vasut , Linus Walleij , Marc Zyngier , Bartosz Golaszewski , Loic Poulain , NXP Linux Team , Peng Fan , Shawn Guo Subject: [PATCH v6 1/2] gpio: mxc: Protect GPIO irqchip RMW with bgpio spinlock Date: Thu, 13 Oct 2022 23:59:45 +0200 Message-Id: <20221013215946.216184-1-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. Reviewed-by: Linus Walleij Reviewed-by: Marc Zyngier 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 V4: Include linux/spinlock.h V5: Use raw_spinlock per 3c938cc5cebcb ("gpio: use raw spinlock for gpio chip shadowed data") V6: No change --- drivers/gpio/gpio-mxc.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/gpio/gpio-mxc.c b/drivers/gpio/gpio-mxc.c index c871602fc5ba9..6cc98a5684ae1 100644 --- a/drivers/gpio/gpio-mxc.c +++ b/drivers/gpio/gpio-mxc.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -147,6 +148,7 @@ 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 +187,8 @@ static int gpio_set_irq_type(struct irq_data *d, u32 type) return -EINVAL; } + raw_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 +208,20 @@ static int gpio_set_irq_type(struct irq_data *d, u32 type) writel(1 << gpio_idx, port->base + GPIO_ISR); + raw_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; + raw_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 +239,8 @@ static void mxc_flip_edge(struct mxc_gpio_port *port, u32 gpio) return; } writel(val | (edge << (bit << 1)), reg); + + raw_spin_unlock_irqrestore(&port->gc.bgpio_lock, flags); } /* handle 32 interrupts in one status register */