[PATCH] Generic IRQ: Add unlocked version of set_irq_handler()

[PATCH] Generic IRQ: Add unlocked version of set_irq_handler()

[Kevin Hilman]

Add unlocked version for use by irq_chip.set_type handlers which may
wish to change handler to level or edge handler when IRQ type is
changed.

The normal set_irq_handler() call cannot be used because it tries to
take irq_desc.lock which is already held when the irq_chip.set_type
hook is called.

Signed-off-by: Kevin Hilman <khilman@mvista.com>
---
 include/linux/irq.h |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/include/linux/irq.h b/include/linux/irq.h
index efc8853..4669be0 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -339,6 +339,13 @@ extern void
 __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
 		  const char *name);
 
+/* caller has locked the irq_desc and both params are valid */
+static inline void __set_irq_handler_unlocked(int irq,
+					      irq_flow_handler_t handler)
+{
+	irq_desc[irq].handle_irq = handler;
+}
+
 /*
  * Set a highlevel flow handler for a given IRQ:
  */
-- 
1.5.3.7

Re: [PATCH] Generic IRQ: Add unlocked version of set_irq_handler()

[Ingo Molnar]

* Kevin Hilman <khilman@mvista.com> wrote:

> Add unlocked version for use by irq_chip.set_type handlers which may 
> wish to change handler to level or edge handler when IRQ type is 
> changed.
> 
> The normal set_irq_handler() call cannot be used because it tries to 
> take irq_desc.lock which is already held when the irq_chip.set_type 
> hook is called.

looks fine to me. Thomas?

	Ingo

Re: [PATCH] Generic IRQ: Add unlocked version of set_irq_handler()

[Thomas Gleixner]

On Wed, 12 Dec 2007, Ingo Molnar wrote:

> 
> * Kevin Hilman <khilman@mvista.com> wrote:
> 
> > Add unlocked version for use by irq_chip.set_type handlers which may 
> > wish to change handler to level or edge handler when IRQ type is 
> > changed.
> > 
> > The normal set_irq_handler() call cannot be used because it tries to 
> > take irq_desc.lock which is already held when the irq_chip.set_type 
> > hook is called.
> 
> looks fine to me. Thomas?

Acked-by: Thomas Gleixner <tglx@linutronix.de>

[PATCH/RFC] OMAP GPIO IRQ rework for generic IRQ subsystem

[Kevin Hilman]

This patchset aims to cleanup OMAP GPIO IRQ handling and use the
generic IRQ framework where possible.  In the process it fixes a
couple bugs and enables correct behavior when GPIO IRQ handlers are
threaded by the -rt patch.

Tested on OMAP3430SDP and 2430SDP with and without -rt patch.

Needs some testing on platforms using edge-triggered IRQs with and
without IRQ patch.

Comments welcome,

Kevin

[PATCH] ARM: OMAP: Fix GPIO IRQ unmask

[Kevin Hilman]

GPIO IRQ unmask doesn't actually do anything useful.  The problem is
hidden by a separate explicit mass unmask at the end of the chained
bank handler.

Signed-off-by: Kevin Hilman <khilman@mvista.com>
---
 arch/arm/plat-omap/gpio.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/arch/arm/plat-omap/gpio.c b/arch/arm/plat-omap/gpio.c
index 1640a37..f5a1ee5 100644
--- a/arch/arm/plat-omap/gpio.c
+++ b/arch/arm/plat-omap/gpio.c
@@ -1145,10 +1145,9 @@ static void gpio_mask_irq(unsigned int irq)
 static void gpio_unmask_irq(unsigned int irq)
 {
 	unsigned int gpio = irq - IH_GPIO_BASE;
-	unsigned int gpio_idx = get_gpio_index(gpio);
 	struct gpio_bank *bank = get_irq_chip_data(irq);
 
-	_set_gpio_irqenable(bank, gpio_idx, 1);
+	_set_gpio_irqenable(bank, gpio, 1);
 }
 
 static struct irq_chip gpio_irq_chip = {
-- 
1.5.3.5

[PATCH] ARM: OMAP: Clear level-triggered GPIO interrupts in unmask hook

[Kevin Hilman]

The clearing was moved to the unmask hook because it is known to run
after the interrupt handler has actually run.  Before this patch, if
interrupts were threaded, the clearing/unmasking of level triggered
interrupts could be done before the threaded handler actually ran.

Signed-off-by: Kevin Hilman <khilman@mvista.com>
---
 arch/arm/plat-omap/gpio.c |   28 ++++++++++++++--------------
 1 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/arch/arm/plat-omap/gpio.c b/arch/arm/plat-omap/gpio.c
index f5a1ee5..09fcd30 100644
--- a/arch/arm/plat-omap/gpio.c
+++ b/arch/arm/plat-omap/gpio.c
@@ -150,6 +150,7 @@ struct gpio_bank {
 	u32 saved_fallingdetect;
 	u32 saved_risingdetect;
 #endif
+	u32 level_mask;
 	spinlock_t lock;
 };
 
@@ -519,6 +520,10 @@ static inline void set_24xx_gpio_triggering(struct gpio_bank *bank, int gpio, in
 		else
 			bank->enabled_non_wakeup_gpios &= ~gpio_bit;
 	}
+
+	bank->level_mask = 
+		__raw_readl(bank->base + OMAP24XX_GPIO_LEVELDETECT0) |
+		__raw_readl(bank->base + OMAP24XX_GPIO_LEVELDETECT1);
 	/* FIXME: Possibly do 'set_irq_handler(j, handle_level_irq)' if only level
 	 * triggering requested. */
 }
@@ -1033,12 +1038,7 @@ static void gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
 			isr &= 0x0000ffff;
 
 		if (cpu_class_is_omap2()) {
-			level_mask =
-				__raw_readl(bank->base +
-					OMAP24XX_GPIO_LEVELDETECT0) |
-				__raw_readl(bank->base +
-					OMAP24XX_GPIO_LEVELDETECT1);
-			level_mask &= enabled;
+			level_mask = bank->level_mask & enabled;
 		}
 
 		/* clear edge sensitive interrupts before handler(s) are
@@ -1100,14 +1100,6 @@ static void gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
 				retrigger |= irq_mask;
 			}
 		}
-
-		if (cpu_class_is_omap2()) {
-			/* clear level sensitive interrupts after handler(s) */
-			_enable_gpio_irqbank(bank, isr_saved & level_mask, 0);
-			_clear_gpio_irqbank(bank, isr_saved & level_mask);
-			_enable_gpio_irqbank(bank, isr_saved & level_mask, 1);
-		}
-
 	}
 	/* if bank has any level sensitive GPIO pin interrupt
 	configured, we must unmask the bank interrupt only after
@@ -1146,7 +1138,15 @@ static void gpio_unmask_irq(unsigned int irq)
 {
 	unsigned int gpio = irq - IH_GPIO_BASE;
 	struct gpio_bank *bank = get_irq_chip_data(irq);
+	unsigned int irq_mask = 1 << get_gpio_index(gpio);
 
+	/* For level-triggered GPIOs, the clearing must be done after
+	 * the HW source is cleared, thus after the handler has run */
+	if (bank->level_mask & irq_mask) {
+		_set_gpio_irqenable(bank, gpio, 0);
+		_clear_gpio_irqstatus(bank, gpio);
+	}
+		
 	_set_gpio_irqenable(bank, gpio, 1);
 }
 
-- 
1.5.3.5

[PATCH] Generic IRQ: Add unlocked version of set_irq_handler()

[Kevin Hilman]

Add unlocked version for use by irq_chip.set_type handlers which may
wish to change handler to level or edge handler when IRQ type is
changed.

The normal set_irq_handler() call cannot be used because it tries to
take irq_desc.lock which is already held when the irq_chip.set_type
hook is called.

Signed-off-by: Kevin Hilman <khilman@mvista.com>
---
 include/linux/irq.h |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/include/linux/irq.h b/include/linux/irq.h
index 879ab83..2465709 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -347,6 +347,13 @@ extern void
 __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
 		  const char *name);
 
+/* caller has locked the irq_desc and both params are valid */
+static inline void __set_irq_handler_unlocked(int irq, 
+					      irq_flow_handler_t handler)
+{
+	irq_desc[irq].handle_irq = handler;
+}
+
 /*
  * Set a highlevel flow handler for a given IRQ:
  */
-- 
1.5.3.5