zte's code,first commit

Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/arch/arm/mach-s3c24xx/irq-s3c2440.c b/ap/os/linux/linux-3.4.x/arch/arm/mach-s3c24xx/irq-s3c2440.c
new file mode 100644
index 0000000..4a18cde
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/arch/arm/mach-s3c24xx/irq-s3c2440.c
@@ -0,0 +1,128 @@
+/* linux/arch/arm/mach-s3c2440/irq.c
+ *
+ * Copyright (c) 2003-2004 Simtec Electronics
+ *	Ben Dooks <ben@simtec.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+*/
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/device.h>
+#include <linux/io.h>
+
+#include <mach/hardware.h>
+#include <asm/irq.h>
+
+#include <asm/mach/irq.h>
+
+#include <mach/regs-irq.h>
+#include <mach/regs-gpio.h>
+
+#include <plat/cpu.h>
+#include <plat/pm.h>
+#include <plat/irq.h>
+
+/* WDT/AC97 */
+
+static void s3c_irq_demux_wdtac97(unsigned int irq,
+				  struct irq_desc *desc)
+{
+	unsigned int subsrc, submsk;
+
+	/* read the current pending interrupts, and the mask
+	 * for what it is available */
+
+	subsrc = __raw_readl(S3C2410_SUBSRCPND);
+	submsk = __raw_readl(S3C2410_INTSUBMSK);
+
+	subsrc &= ~submsk;
+	subsrc >>= 13;
+	subsrc &= 3;
+
+	if (subsrc != 0) {
+		if (subsrc & 1) {
+			generic_handle_irq(IRQ_S3C2440_WDT);
+		}
+		if (subsrc & 2) {
+			generic_handle_irq(IRQ_S3C2440_AC97);
+		}
+	}
+}
+
+
+#define INTMSK_WDT	 (1UL << (IRQ_WDT - IRQ_EINT0))
+
+static void
+s3c_irq_wdtac97_mask(struct irq_data *data)
+{
+	s3c_irqsub_mask(data->irq, INTMSK_WDT, 3 << 13);
+}
+
+static void
+s3c_irq_wdtac97_unmask(struct irq_data *data)
+{
+	s3c_irqsub_unmask(data->irq, INTMSK_WDT);
+}
+
+static void
+s3c_irq_wdtac97_ack(struct irq_data *data)
+{
+	s3c_irqsub_maskack(data->irq, INTMSK_WDT, 3 << 13);
+}
+
+static struct irq_chip s3c_irq_wdtac97 = {
+	.irq_mask	= s3c_irq_wdtac97_mask,
+	.irq_unmask	= s3c_irq_wdtac97_unmask,
+	.irq_ack	= s3c_irq_wdtac97_ack,
+};
+
+static int s3c2440_irq_add(struct device *dev, struct subsys_interface *sif)
+{
+	unsigned int irqno;
+
+	printk("S3C2440: IRQ Support\n");
+
+	/* add new chained handler for wdt, ac7 */
+
+	irq_set_chip_and_handler(IRQ_WDT, &s3c_irq_level_chip,
+				 handle_level_irq);
+	irq_set_chained_handler(IRQ_WDT, s3c_irq_demux_wdtac97);
+
+	for (irqno = IRQ_S3C2440_WDT; irqno <= IRQ_S3C2440_AC97; irqno++) {
+		irq_set_chip_and_handler(irqno, &s3c_irq_wdtac97,
+					 handle_level_irq);
+		set_irq_flags(irqno, IRQF_VALID);
+	}
+
+	return 0;
+}
+
+static struct subsys_interface s3c2440_irq_interface = {
+	.name		= "s3c2440_irq",
+	.subsys		= &s3c2440_subsys,
+	.add_dev	= s3c2440_irq_add,
+};
+
+static int s3c2440_irq_init(void)
+{
+	return subsys_interface_register(&s3c2440_irq_interface);
+}
+
+arch_initcall(s3c2440_irq_init);
+