[PATCH] IRQ type flags

Some ARM platforms have the ability to program the interrupt controller to
detect various interrupt edges and/or levels.  For some platforms, this is
critical to setup correctly, particularly those which the setting is dependent
on the device.

Currently, ARM drivers do (eg) the following:

	err = request_irq(irq, ...);

	set_irq_type(irq, IRQT_RISING);

However, if the interrupt has previously been programmed to be level sensitive
(for whatever reason) then this will cause an interrupt storm.

Hence, if we combine set_irq_type() with request_irq(), we can then safely set
the type prior to unmasking the interrupt.  The unfortunate problem is that in
order to support this, these flags need to be visible outside of the ARM
architecture - drivers such as smc91x need these flags and they're
cross-architecture.

Finally, the SA_TRIGGER_* flag passed to request_irq() should reflect the
property that the device would like.  The IRQ controller code should do its
best to select the most appropriate supported mode.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/arm/kernel/irq.c

@@ -684,8 +684,12 @@ int setup_irq(unsigned int irq, struct irqaction *new)
 	spin_lock_irqsave(&irq_controller_lock, flags);
 	p = &desc->action;
 	if ((old = *p) != NULL) {
-		/* Can't share interrupts unless both agree to */
-		if (!(old->flags & new->flags & SA_SHIRQ)) {
+		/*
+		 * Can't share interrupts unless both agree to and are
+		 * the same type.
+		 */
+		if (!(old->flags & new->flags & SA_SHIRQ) ||
+		    (~old->flags & new->flags) & SA_TRIGGER_MASK) {
 			spin_unlock_irqrestore(&irq_controller_lock, flags);
 			return -EBUSY;
 		}
@@ -705,6 +709,12 @@ int setup_irq(unsigned int irq, struct irqaction *new)
 		desc->running = 0;
 		desc->pending = 0;
 		desc->disable_depth = 1;
+
+		if (new->flags & SA_TRIGGER_MASK) {
+			unsigned int type = new->flags & SA_TRIGGER_MASK;
+			desc->chip->set_type(irq, type);
+		}
+
 		if (!desc->noautoenable) {
 			desc->disable_depth = 0;
 			desc->chip->unmask(irq);

arch/arm/mach-omap1/serial.c

@@ -252,9 +252,8 @@ static void __init omap_serial_set_port_wakeup(int gpio_nr)
 		return;
 	}
 	omap_set_gpio_direction(gpio_nr, 1);
-	set_irq_type(OMAP_GPIO_IRQ(gpio_nr), IRQT_RISING);
 	ret = request_irq(OMAP_GPIO_IRQ(gpio_nr), &omap_serial_wake_interrupt,
-			  0, "serial wakeup", NULL);
+			  SA_TRIGGER_RISING, "serial wakeup", NULL);
 	if (ret) {
 		omap_free_gpio(gpio_nr);
 		printk(KERN_ERR "No interrupt for UART wake GPIO: %i\n",

arch/arm/mach-pxa/corgi.c

@@ -213,15 +213,14 @@ static int corgi_mci_init(struct device *dev, irqreturn_t (*corgi_detect_int)(in
 
 	corgi_mci_platform_data.detect_delay = msecs_to_jiffies(250);
 
-	err = request_irq(CORGI_IRQ_GPIO_nSD_DETECT, corgi_detect_int, SA_INTERRUPT,
-			     "MMC card detect", data);
+	err = request_irq(CORGI_IRQ_GPIO_nSD_DETECT, corgi_detect_int,
+			  SA_INTERRUPT | SA_TRIGGER_RISING | SA_TRIGGER_FALLING,
+			  "MMC card detect", data);
 	if (err) {
 		printk(KERN_ERR "corgi_mci_init: MMC/SD: can't request MMC card detect IRQ\n");
 		return -1;
 	}
 
-	set_irq_type(CORGI_IRQ_GPIO_nSD_DETECT, IRQT_BOTHEDGE);
-
 	return 0;
 }
 

arch/arm/mach-pxa/poodle.c

@@ -146,15 +146,14 @@ static int poodle_mci_init(struct device *dev, irqreturn_t (*poodle_detect_int)(
 
 	poodle_mci_platform_data.detect_delay = msecs_to_jiffies(250);
 
-	err = request_irq(POODLE_IRQ_GPIO_nSD_DETECT, poodle_detect_int, SA_INTERRUPT,
-			     "MMC card detect", data);
+	err = request_irq(POODLE_IRQ_GPIO_nSD_DETECT, poodle_detect_int,
+			  SA_INTERRUPT | SA_TRIGGER_RISING | SA_TRIGGER_FALLING,
+			  "MMC card detect", data);
 	if (err) {
 		printk(KERN_ERR "poodle_mci_init: MMC/SD: can't request MMC card detect IRQ\n");
 		return -1;
 	}
 
-	set_irq_type(POODLE_IRQ_GPIO_nSD_DETECT, IRQT_BOTHEDGE);
-
 	return 0;
 }
 

arch/arm/mach-pxa/spitz.c

@@ -296,15 +296,14 @@ static int spitz_mci_init(struct device *dev, irqreturn_t (*spitz_detect_int)(in
 
 	spitz_mci_platform_data.detect_delay = msecs_to_jiffies(250);
 
-	err = request_irq(SPITZ_IRQ_GPIO_nSD_DETECT, spitz_detect_int, SA_INTERRUPT,
-			     "MMC card detect", data);
+	err = request_irq(SPITZ_IRQ_GPIO_nSD_DETECT, spitz_detect_int,
+			  SA_INTERRUPT | SA_TRIGGER_RISING | SA_TRIGGER_FALLING,
+			  "MMC card detect", data);
 	if (err) {
 		printk(KERN_ERR "spitz_mci_init: MMC/SD: can't request MMC card detect IRQ\n");
 		return -1;
 	}
 
-	set_irq_type(SPITZ_IRQ_GPIO_nSD_DETECT, IRQT_BOTHEDGE);
-
 	return 0;
 }
 

arch/arm/mach-s3c2410/usb-simtec.c

@@ -84,13 +84,13 @@ static void usb_simtec_enableoc(struct s3c2410_hcd_info *info, int on)
 	int ret;
 
 	if (on) {
-		ret = request_irq(IRQ_USBOC, usb_simtec_ocirq, SA_INTERRUPT,
+		ret = request_irq(IRQ_USBOC, usb_simtec_ocirq,
+				  SA_INTERRUPT | SA_TRIGGER_RISING |
+				   SA_TRIGGER_FALLING,
 				  "USB Over-current", info);
 		if (ret != 0) {
 			printk(KERN_ERR "failed to request usb oc irq\n");
 		}
-
-		set_irq_type(IRQ_USBOC, IRQT_BOTHEDGE);
 	} else {
 		free_irq(IRQ_USBOC, info);
 	}

drivers/i2c/chips/tps65010.c

@@ -494,6 +494,7 @@ tps65010_probe(struct i2c_adapter *bus, int address, int kind)
 {
 	struct tps65010		*tps;
 	int			status;
+	unsigned long		irqflags;
 
 	if (the_tps) {
 		dev_dbg(&bus->dev, "only one %s for now\n", DRIVER_NAME);
@@ -520,13 +521,14 @@ tps65010_probe(struct i2c_adapter *bus, int address, int kind)
 	}
 
 #ifdef	CONFIG_ARM
+	irqflags = SA_SAMPLE_RANDOM | SA_TRIGGER_LOW;
 	if (machine_is_omap_h2()) {
 		tps->model = TPS65010;
 		omap_cfg_reg(W4_GPIO58);
 		tps->irq = OMAP_GPIO_IRQ(58);
 		omap_request_gpio(58);
 		omap_set_gpio_direction(58, 1);
-		set_irq_type(tps->irq, IRQT_FALLING);
+		irqflags |= SA_TRIGGER_FALLING;
 	}
 	if (machine_is_omap_osk()) {
 		tps->model = TPS65010;
@@ -534,7 +536,7 @@ tps65010_probe(struct i2c_adapter *bus, int address, int kind)
 		tps->irq = OMAP_GPIO_IRQ(OMAP_MPUIO(1));
 		omap_request_gpio(OMAP_MPUIO(1));
 		omap_set_gpio_direction(OMAP_MPUIO(1), 1);
-		set_irq_type(tps->irq, IRQT_FALLING);
+		irqflags |= SA_TRIGGER_FALLING;
 	}
 	if (machine_is_omap_h3()) {
 		tps->model = TPS65013;
@@ -542,13 +544,12 @@ tps65010_probe(struct i2c_adapter *bus, int address, int kind)
 		// FIXME set up this board's IRQ ...
 	}
 #else
-#define set_irq_type(num,trigger)	do{}while(0)
+	irqflags = SA_SAMPLE_RANDOM;
 #endif
 
 	if (tps->irq > 0) {
-		set_irq_type(tps->irq, IRQT_LOW);
 		status = request_irq(tps->irq, tps65010_irq,
-			SA_SAMPLE_RANDOM, DRIVER_NAME, tps);
+			irqflags, DRIVER_NAME, tps);
 		if (status < 0) {
 			dev_dbg(&tps->client.dev, "can't get IRQ %d, err %d\n",
 					tps->irq, status);

drivers/input/keyboard/corgikbd.c

@@ -19,7 +19,6 @@
 #include <linux/jiffies.h>
 #include <linux/module.h>
 #include <linux/slab.h>
-#include <asm/irq.h>
 
 #include <asm/arch/corgi.h>
 #include <asm/arch/hardware.h>
@@ -343,10 +342,9 @@ static int __init corgikbd_probe(struct platform_device *pdev)
 	for (i = 0; i < CORGI_KEY_SENSE_NUM; i++) {
 		pxa_gpio_mode(CORGI_GPIO_KEY_SENSE(i) | GPIO_IN);
 		if (request_irq(CORGI_IRQ_GPIO_KEY_SENSE(i), corgikbd_interrupt,
-						SA_INTERRUPT, "corgikbd", corgikbd))
+				SA_INTERRUPT | SA_TRIGGER_RISING,
+				"corgikbd", corgikbd))
 			printk(KERN_WARNING "corgikbd: Can't get IRQ: %d!\n", i);
-		else
-			set_irq_type(CORGI_IRQ_GPIO_KEY_SENSE(i),IRQT_RISING);
 	}
 
 	/* Set Strobe lines as outputs - set high */

drivers/input/keyboard/spitzkbd.c

@@ -19,7 +19,6 @@
 #include <linux/jiffies.h>
 #include <linux/module.h>
 #include <linux/slab.h>
-#include <asm/irq.h>
 
 #include <asm/arch/spitz.h>
 #include <asm/arch/hardware.h>
@@ -407,10 +406,9 @@ static int __init spitzkbd_probe(struct platform_device *dev)
 	for (i = 0; i < SPITZ_KEY_SENSE_NUM; i++) {
 		pxa_gpio_mode(spitz_senses[i] | GPIO_IN);
 		if (request_irq(IRQ_GPIO(spitz_senses[i]), spitzkbd_interrupt,
-						SA_INTERRUPT, "Spitzkbd Sense", spitzkbd))
+				SA_INTERRUPT|SA_TRIGGER_RISING,
+				"Spitzkbd Sense", spitzkbd))
 			printk(KERN_WARNING "spitzkbd: Can't get Sense IRQ: %d!\n", i);
-		else
-			set_irq_type(IRQ_GPIO(spitz_senses[i]),IRQT_RISING);
 	}
 
 	/* Set Strobe lines as outputs - set high */
@@ -422,15 +420,18 @@ static int __init spitzkbd_probe(struct platform_device *dev)
 	pxa_gpio_mode(SPITZ_GPIO_SWA | GPIO_IN);
 	pxa_gpio_mode(SPITZ_GPIO_SWB | GPIO_IN);
 
-	request_irq(SPITZ_IRQ_GPIO_SYNC, spitzkbd_interrupt, SA_INTERRUPT, "Spitzkbd Sync", spitzkbd);
-	request_irq(SPITZ_IRQ_GPIO_ON_KEY, spitzkbd_interrupt, SA_INTERRUPT, "Spitzkbd PwrOn", spitzkbd);
-	request_irq(SPITZ_IRQ_GPIO_SWA, spitzkbd_hinge_isr, SA_INTERRUPT, "Spitzkbd SWA", spitzkbd);
-	request_irq(SPITZ_IRQ_GPIO_SWB, spitzkbd_hinge_isr, SA_INTERRUPT, "Spitzkbd SWB", spitzkbd);
-
-	set_irq_type(SPITZ_IRQ_GPIO_SYNC, IRQT_BOTHEDGE);
-	set_irq_type(SPITZ_IRQ_GPIO_ON_KEY, IRQT_BOTHEDGE);
-	set_irq_type(SPITZ_IRQ_GPIO_SWA, IRQT_BOTHEDGE);
-	set_irq_type(SPITZ_IRQ_GPIO_SWB, IRQT_BOTHEDGE);
+	request_irq(SPITZ_IRQ_GPIO_SYNC, spitzkbd_interrupt,
+		    SA_INTERRUPT | SA_TRIGGER_RISING | SA_TRIGGER_FALLING,
+		    "Spitzkbd Sync", spitzkbd);
+	request_irq(SPITZ_IRQ_GPIO_ON_KEY, spitzkbd_interrupt,
+		    SA_INTERRUPT | SA_TRIGGER_RISING | SA_TRIGGER_FALLING,
+		    "Spitzkbd PwrOn", spitzkbd);
+	request_irq(SPITZ_IRQ_GPIO_SWA, spitzkbd_hinge_isr,
+		    SA_INTERRUPT | SA_TRIGGER_RISING | SA_TRIGGER_FALLING,
+		    "Spitzkbd SWA", spitzkbd);
+	request_irq(SPITZ_IRQ_GPIO_SWB, spitzkbd_hinge_isr,
+		    SA_INTERRUPT | SA_TRIGGER_RISING | SA_TRIGGER_FALLING,
+		    "Spitzkbd SWB", spitzkbd);
 
 	printk(KERN_INFO "input: Spitz Keyboard Registered\n");
 

drivers/mfd/ucb1x00-core.c

@@ -27,7 +27,6 @@
 
 #include <asm/dma.h>
 #include <asm/hardware.h>
-#include <asm/irq.h>
 
 #include "ucb1x00.h"
 
@@ -507,14 +506,14 @@ static int ucb1x00_probe(struct mcp *mcp)
 		goto err_free;
 	}
 
-	ret = request_irq(ucb->irq, ucb1x00_irq, 0, "UCB1x00", ucb);
+	ret = request_irq(ucb->irq, ucb1x00_irq, SA_TRIGGER_RISING,
+			  "UCB1x00", ucb);
 	if (ret) {
 		printk(KERN_ERR "ucb1x00: unable to grab irq%d: %d\n",
 			ucb->irq, ret);
 		goto err_free;
 	}
 
-	set_irq_type(ucb->irq, IRQT_RISING);
 	mcp_set_drvdata(mcp, ucb);
 
 	ret = class_device_register(&ucb->cdev);

drivers/net/smc91x.c

@@ -88,7 +88,6 @@ static const char version[] =
 #include <linux/skbuff.h>
 
 #include <asm/io.h>
-#include <asm/irq.h>
 
 #include "smc91x.h"
 
@@ -2007,12 +2006,10 @@ static int __init smc_probe(struct net_device *dev, void __iomem *ioaddr)
 	}
 
 	/* Grab the IRQ */
-      	retval = request_irq(dev->irq, &smc_interrupt, 0, dev->name, dev);
+      	retval = request_irq(dev->irq, &smc_interrupt, SMC_IRQ_FLAGS, dev->name, dev);
       	if (retval)
       		goto err_out;
 
-	set_irq_type(dev->irq, SMC_IRQ_TRIGGER_TYPE);
-
 #ifdef SMC_USE_PXA_DMA
 	{
 		int dma = pxa_request_dma(dev->name, DMA_PRIO_LOW,

drivers/net/smc91x.h

@@ -90,7 +90,7 @@
 			__l--;						\
 		}							\
 	} while (0)
-#define set_irq_type(irq, type)
+#define SMC_IRQ_FLAGS		(0)
 
 #elif defined(CONFIG_SA1100_PLEB)
 /* We can only do 16-bit reads and writes in the static memory space. */
@@ -109,7 +109,7 @@
 #define SMC_outw(v, a, r)	writew(v, (a) + (r))
 #define SMC_outsw(a, r, p, l)	writesw((a) + (r), p, l)
 
-#define set_irq_type(irq, type) do {} while (0)
+#define SMC_IRQ_FLAGS		(0)
 
 #elif defined(CONFIG_SA1100_ASSABET)
 
@@ -185,11 +185,11 @@ SMC_outw(u16 val, void __iomem *ioaddr, int reg)
 #include <asm/mach-types.h>
 #include <asm/arch/cpu.h>
 
-#define	SMC_IRQ_TRIGGER_TYPE (( \
+#define	SMC_IRQ_FLAGS (( \
 		   machine_is_omap_h2() \
 		|| machine_is_omap_h3() \
 		|| (machine_is_omap_innovator() && !cpu_is_omap1510()) \
-	) ? IRQT_FALLING : IRQT_RISING)
+	) ? SA_TRIGGER_FALLING : SA_TRIGGER_RISING)
 
 
 #elif	defined(CONFIG_SH_SH4202_MICRODEV)
@@ -209,7 +209,7 @@ SMC_outw(u16 val, void __iomem *ioaddr, int reg)
 #define SMC_insw(a, r, p, l)	insw((a) + (r) - 0xa0000000, p, l)
 #define SMC_outsw(a, r, p, l)	outsw((a) + (r) - 0xa0000000, p, l)
 
-#define set_irq_type(irq, type)	do {} while(0)
+#define SMC_IRQ_FLAGS		(0)
 
 #elif	defined(CONFIG_ISA)
 
@@ -237,7 +237,7 @@ SMC_outw(u16 val, void __iomem *ioaddr, int reg)
 #define SMC_insw(a, r, p, l)	insw(((u32)a) + (r), p, l)
 #define SMC_outsw(a, r, p, l)	outsw(((u32)a) + (r), p, l)
 
-#define set_irq_type(irq, type)	do {} while(0)
+#define SMC_IRQ_FLAGS		(0)
 
 #define RPC_LSA_DEFAULT		RPC_LED_TX_RX
 #define RPC_LSB_DEFAULT		RPC_LED_100_10
@@ -319,7 +319,7 @@ static inline void SMC_outsw (unsigned long a, int r, unsigned char* p, int l)
 			au_writew(*_p++ , _a); \
 	} while(0)
 
-#define set_irq_type(irq, type) do {} while (0)
+#define SMC_IRQ_FLAGS		(0)
 
 #else
 
@@ -342,8 +342,8 @@ static inline void SMC_outsw (unsigned long a, int r, unsigned char* p, int l)
 
 #endif
 
-#ifndef	SMC_IRQ_TRIGGER_TYPE
-#define	SMC_IRQ_TRIGGER_TYPE	IRQT_RISING
+#ifndef	SMC_IRQ_FLAGS
+#define	SMC_IRQ_FLAGS		SA_TRIGGER_RISING
 #endif
 
 #ifdef SMC_USE_PXA_DMA

include/asm-arm/irq.h

@@ -25,10 +25,14 @@ extern void disable_irq_nosync(unsigned int);
 extern void disable_irq(unsigned int);
 extern void enable_irq(unsigned int);
 
-#define __IRQT_FALEDGE	(1 << 0)
-#define __IRQT_RISEDGE	(1 << 1)
-#define __IRQT_LOWLVL	(1 << 2)
-#define __IRQT_HIGHLVL	(1 << 3)
+/*
+ * These correspond with the SA_TRIGGER_* defines, and therefore the
+ * IRQRESOURCE_IRQ_* defines.
+ */
+#define __IRQT_RISEDGE	(1 << 0)
+#define __IRQT_FALEDGE	(1 << 1)
+#define __IRQT_HIGHLVL	(1 << 2)
+#define __IRQT_LOWLVL	(1 << 3)
 
 #define IRQT_NOEDGE	(0)
 #define IRQT_RISING	(__IRQT_RISEDGE)

include/linux/signal.h

@@ -18,6 +18,19 @@
 #define SA_PROBE		SA_ONESHOT
 #define SA_SAMPLE_RANDOM	SA_RESTART
 #define SA_SHIRQ		0x04000000
+/*
+ * As above, these correspond to the IORESOURCE_IRQ_* defines in
+ * linux/ioport.h to select the interrupt line behaviour.  When
+ * requesting an interrupt without specifying a SA_TRIGGER, the
+ * setting should be assumed to be "as already configured", which
+ * may be as per machine or firmware initialisation.
+ */
+#define SA_TRIGGER_LOW		0x00000008
+#define SA_TRIGGER_HIGH		0x00000004
+#define SA_TRIGGER_FALLING	0x00000002
+#define SA_TRIGGER_RISING	0x00000001
+#define SA_TRIGGER_MASK	(SA_TRIGGER_HIGH|SA_TRIGGER_LOW|\
+				 SA_TRIGGER_RISING|SA_TRIGGER_FALLING)
 
 /*
  * Real Time signals may be queued.