Commit 7a26d3a3 authored by eric miao's avatar eric miao Committed by Russell King
Browse files

[ARM] pxa: generalize the muxed gpio IRQ handling code with loop and ffs() 



1. As David Brownell suggests, using ffs() is going to make the loop
   a bit faster (by avoiding unnecessary shift and iteration)

2. Russell suggested find_{first,next}_bit() being used with the
   gedr[] array

Signed-off-by: default avatareric miao <eric.miao@marvell.com>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent d72b1370

arch/arm/mach-pxa/irq.c

+16 −58
Original line number Diff line number Diff line
@@ -178,73 +178,31 @@ static struct irq_chip pxa_low_gpio_chip = { 
 * Demux handler for GPIO>=2 edge detect interrupts

 */



#define GEDR_BITS	(sizeof(gedr) * BITS_PER_BYTE)



static void pxa_gpio_demux_handler(unsigned int irq, struct irq_desc *desc)

{

	unsigned int mask;

	int loop;

	int loop, bit, n;

	unsigned long gedr[4];



	do {

		loop = 0;

		gedr[0] = GEDR0 & GPIO_IRQ_mask[0] & ~3;

		gedr[1] = GEDR1 & GPIO_IRQ_mask[1];

		gedr[2] = GEDR2 & GPIO_IRQ_mask[2];

		gedr[3] = GEDR3 & GPIO_IRQ_mask[3];



		mask = GEDR0 & GPIO_IRQ_mask[0] & ~3;

		if (mask) {

			GEDR0 = mask;

			irq = IRQ_GPIO(2);

			desc = irq_desc + irq;

			mask >>= 2;

			do {

				if (mask & 1)

					desc_handle_irq(irq, desc);

				irq++;

				desc++;

				mask >>= 1;

			} while (mask);

			loop = 1;

		}

		GEDR0 = gedr[0]; GEDR1 = gedr[1];

		GEDR2 = gedr[2]; GEDR3 = gedr[3];



		mask = GEDR1 & GPIO_IRQ_mask[1];

		if (mask) {

			GEDR1 = mask;

			irq = IRQ_GPIO(32);

			desc = irq_desc + irq;

			do {

				if (mask & 1)

					desc_handle_irq(irq, desc);

				irq++;

				desc++;

				mask >>= 1;

			} while (mask);

		loop = 0;

		bit = find_first_bit(gedr, GEDR_BITS);

		while (bit < GEDR_BITS) {

			loop = 1;

		}



		mask = GEDR2 & GPIO_IRQ_mask[2];

		if (mask) {

			GEDR2 = mask;

			irq = IRQ_GPIO(64);

			desc = irq_desc + irq;

			do {

				if (mask & 1)

					desc_handle_irq(irq, desc);

				irq++;

				desc++;

				mask >>= 1;

			} while (mask);

			loop = 1;

		}

			n = PXA_GPIO_IRQ_BASE + bit;

			desc_handle_irq(n, irq_desc + n);



		mask = GEDR3 & GPIO_IRQ_mask[3];

		if (mask) {

			GEDR3 = mask;

			irq = IRQ_GPIO(96);

			desc = irq_desc + irq;

			do {

				if (mask & 1)

					desc_handle_irq(irq, desc);

				irq++;

				desc++;

				mask >>= 1;

			} while (mask);

			loop = 1;

			bit = find_next_bit(gedr, GEDR_BITS, bit + 1);

		}

	} while (loop);

}