From: Ben Nizette Date: Sat, 18 Apr 2009 03:35:57 +0000 (-0700) Subject: Input: omap-keypad - use disable_irq_nosync() in irq handler X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=0f751719e4e689efbe537233552e5f0529ecb8ce;p=openwrt%2Fstaging%2Fblogic.git Input: omap-keypad - use disable_irq_nosync() in irq handler disable_irq() waits for all running handlers to complete before returning. As such, if it's used to disable an interrupt from that interrupt's handler it will deadlock. This replaces the dangerous instances with the _nosync() variant which doesn't have this problem. Signed-off-by: Ben Nizette Signed-off-by: Dmitry Torokhov --- diff --git a/drivers/input/keyboard/omap-keypad.c b/drivers/input/keyboard/omap-keypad.c index 058fa8b02c21..87ec7b18ac69 100644 --- a/drivers/input/keyboard/omap-keypad.c +++ b/drivers/input/keyboard/omap-keypad.c @@ -100,8 +100,20 @@ static irqreturn_t omap_kp_interrupt(int irq, void *dev_id) /* disable keyboard interrupt and schedule for handling */ if (cpu_is_omap24xx()) { int i; - for (i = 0; i < omap_kp->rows; i++) - disable_irq(gpio_to_irq(row_gpios[i])); + + for (i = 0; i < omap_kp->rows; i++) { + int gpio_irq = gpio_to_irq(row_gpios[i]); + /* + * The interrupt which we're currently handling should + * be disabled _nosync() to avoid deadlocks waiting + * for this handler to complete. All others should + * be disabled the regular way for SMP safety. + */ + if (gpio_irq == irq) + disable_irq_nosync(gpio_irq); + else + disable_irq(gpio_irq); + } } else /* disable keyboard interrupt and schedule for handling */ omap_writew(1, OMAP_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);