From 61819549f572edd7fce53f228c0d8420cdc85f71 Mon Sep 17 00:00:00 2001 From: Gregory CLEMENT Date: Thu, 2 Apr 2015 17:11:11 +0200 Subject: [PATCH] gpio: mvebu: Fix mask/unmask managment per irq chip type Level IRQ handlers and edge IRQ handler are managed by tow different sets of registers. But currently the driver uses the same mask for the both registers. It lead to issues with the following scenario: First, an IRQ is requested on a GPIO to be triggered on front. After, this an other IRQ is requested for a GPIO of the same bank but triggered on level. Then the first one will be also setup to be triggered on level. It leads to an interrupt storm. The different kind of handler are already associated with two different irq chip type. With this patch the driver uses a private mask for each one which solves this issue. It has been tested on an Armada XP based board and on an Armada 375 board. For the both boards, with this patch is applied, there is no such interrupt storm when running the previous scenario. This bug was already fixed but in a different way in the legacy version of this driver by Evgeniy Dushistov: 9ece8839b1277fb9128ff6833411614ab6c88d68 "ARM: orion: Fix for certain sequence of request_irq can cause irq storm". The fact the new version of the gpio drive could be affected had been discussed there: http://thread.gmane.org/gmane.linux.ports.arm.kernel/344670/focus=364012 Reported-by: Evgeniy A. Dushistov Signed-off-by: Gregory CLEMENT Cc: # v3.7 + Signed-off-by: Linus Walleij --- drivers/gpio/gpio-mvebu.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c index d0bc123c7975..1a54205860f5 100644 --- a/drivers/gpio/gpio-mvebu.c +++ b/drivers/gpio/gpio-mvebu.c @@ -320,11 +320,13 @@ static void mvebu_gpio_edge_irq_mask(struct irq_data *d) { struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); struct mvebu_gpio_chip *mvchip = gc->private; + struct irq_chip_type *ct = irq_data_get_chip_type(d); u32 mask = 1 << (d->irq - gc->irq_base); irq_gc_lock(gc); - gc->mask_cache &= ~mask; - writel_relaxed(gc->mask_cache, mvebu_gpioreg_edge_mask(mvchip)); + ct->mask_cache_priv &= ~mask; + + writel_relaxed(ct->mask_cache_priv, mvebu_gpioreg_edge_mask(mvchip)); irq_gc_unlock(gc); } @@ -332,11 +334,13 @@ static void mvebu_gpio_edge_irq_unmask(struct irq_data *d) { struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); struct mvebu_gpio_chip *mvchip = gc->private; + struct irq_chip_type *ct = irq_data_get_chip_type(d); + u32 mask = 1 << (d->irq - gc->irq_base); irq_gc_lock(gc); - gc->mask_cache |= mask; - writel_relaxed(gc->mask_cache, mvebu_gpioreg_edge_mask(mvchip)); + ct->mask_cache_priv |= mask; + writel_relaxed(ct->mask_cache_priv, mvebu_gpioreg_edge_mask(mvchip)); irq_gc_unlock(gc); } @@ -344,11 +348,13 @@ static void mvebu_gpio_level_irq_mask(struct irq_data *d) { struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); struct mvebu_gpio_chip *mvchip = gc->private; + struct irq_chip_type *ct = irq_data_get_chip_type(d); + u32 mask = 1 << (d->irq - gc->irq_base); irq_gc_lock(gc); - gc->mask_cache &= ~mask; - writel_relaxed(gc->mask_cache, mvebu_gpioreg_level_mask(mvchip)); + ct->mask_cache_priv &= ~mask; + writel_relaxed(ct->mask_cache_priv, mvebu_gpioreg_level_mask(mvchip)); irq_gc_unlock(gc); } @@ -356,11 +362,13 @@ static void mvebu_gpio_level_irq_unmask(struct irq_data *d) { struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); struct mvebu_gpio_chip *mvchip = gc->private; + struct irq_chip_type *ct = irq_data_get_chip_type(d); + u32 mask = 1 << (d->irq - gc->irq_base); irq_gc_lock(gc); - gc->mask_cache |= mask; - writel_relaxed(gc->mask_cache, mvebu_gpioreg_level_mask(mvchip)); + ct->mask_cache_priv |= mask; + writel_relaxed(ct->mask_cache_priv, mvebu_gpioreg_level_mask(mvchip)); irq_gc_unlock(gc); }