Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761911Ab0HFSoH (ORCPT ); Fri, 6 Aug 2010 14:44:07 -0400 Received: from kroah.org ([198.145.64.141]:48544 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761662Ab0HFSfS (ORCPT ); Fri, 6 Aug 2010 14:35:18 -0400 X-Mailbox-Line: From gregkh@clark.site Fri Aug 6 11:32:00 2010 Message-Id: <20100806183200.209512682@clark.site> User-Agent: quilt/0.48-11.2 Date: Fri, 06 Aug 2010 11:30:23 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Juergen Beisert , Daniel Mack , Baruch Siach , Sascha Hauer Subject: [02/38] arm/imx/gpio: add spinlock protection In-Reply-To: <20100806183250.GA23019@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2488 Lines: 81 2.6.35-stable review patch. If anyone has any objections, please let us know. ------------------ From: Baruch Siach commit 14cb0deb66fcfca8fdbef75da8c84b5405a8c767 upstream. The GPIO registers need protection from concurrent access for operations that are not atomic. Cc: Juergen Beisert Cc: Daniel Mack Reported-by: rpkamiak@rockwellcollins.com Signed-off-by: Baruch Siach Signed-off-by: Sascha Hauer Signed-off-by: Greg Kroah-Hartman --- arch/arm/plat-mxc/gpio.c | 8 ++++++++ arch/arm/plat-mxc/include/mach/gpio.h | 1 + 2 files changed, 9 insertions(+) --- a/arch/arm/plat-mxc/gpio.c +++ b/arch/arm/plat-mxc/gpio.c @@ -214,13 +214,16 @@ static void _set_gpio_direction(struct g struct mxc_gpio_port *port = container_of(chip, struct mxc_gpio_port, chip); u32 l; + unsigned long flags; + spin_lock_irqsave(&port->lock, flags); l = __raw_readl(port->base + GPIO_GDIR); if (dir) l |= 1 << offset; else l &= ~(1 << offset); __raw_writel(l, port->base + GPIO_GDIR); + spin_unlock_irqrestore(&port->lock, flags); } static void mxc_gpio_set(struct gpio_chip *chip, unsigned offset, int value) @@ -229,9 +232,12 @@ static void mxc_gpio_set(struct gpio_chi container_of(chip, struct mxc_gpio_port, chip); void __iomem *reg = port->base + GPIO_DR; u32 l; + unsigned long flags; + spin_lock_irqsave(&port->lock, flags); l = (__raw_readl(reg) & (~(1 << offset))) | (value << offset); __raw_writel(l, reg); + spin_unlock_irqrestore(&port->lock, flags); } static int mxc_gpio_get(struct gpio_chip *chip, unsigned offset) @@ -285,6 +291,8 @@ int __init mxc_gpio_init(struct mxc_gpio port[i].chip.base = i * 32; port[i].chip.ngpio = 32; + spin_lock_init(&port[i].lock); + /* its a serious configuration bug when it fails */ BUG_ON( gpiochip_add(&port[i].chip) < 0 ); --- a/arch/arm/plat-mxc/include/mach/gpio.h +++ b/arch/arm/plat-mxc/include/mach/gpio.h @@ -36,6 +36,7 @@ struct mxc_gpio_port { int virtual_irq_start; struct gpio_chip chip; u32 both_edges; + spinlock_t lock; }; int mxc_gpio_init(struct mxc_gpio_port*, int); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/