[ARM] 3783/1: S3C2412: fix IRQ_EINT0 to IRQ_EINT3 handling

Patch from Ben Dooks

The IRQ_EINT0 through IRQ_EINT3 handling has changed
on the S3C2412 from the previous SoCs in the range,
and thus we need to add code to handle this.

The changes come about due to these IRQs being
displayed in two different registers, and needing to
be acked and masked in both.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

4 files changed, 138 insertions, 2 deletions

diff --git a/arch/arm/mach-s3c2410/Makefile b/arch/arm/mach-s3c2410/Makefile
index 273e05f2b8de..0eadec916214 100644
--- a/arch/arm/mach-s3c2410/Makefile
+++ b/arch/arm/mach-s3c2410/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_PM_SIMTEC)		+= pm-simtec.o
 
 # S3C2412 support
 obj-$(CONFIG_CPU_S3C2412)       += s3c2412.o
+obj-$(CONFIG_CPU_S3C2412)       += s3c2412-irq.o
 obj-$(CONFIG_CPU_S3C2412)       += s3c2412-clock.o
 
 #
diff --git a/arch/arm/mach-s3c2410/irq.c b/arch/arm/mach-s3c2410/irq.c
index 6822dc7f7799..cd6139b35999 100644
--- a/arch/arm/mach-s3c2410/irq.c
+++ b/arch/arm/mach-s3c2410/irq.c
@@ -86,7 +86,7 @@ unsigned long s3c_irqwake_intmask	= 0xffffffffL;
 unsigned long s3c_irqwake_eintallow     = 0x0000fff0L;
 unsigned long s3c_irqwake_eintmask      = 0xffffffffL;
 
-static int
+int
 s3c_irq_wake(unsigned int irqno, unsigned int state)
 {
         unsigned long irqbit = 1 << (irqno - IRQ_EINT0);
@@ -260,7 +260,7 @@ s3c_irqext_unmask(unsigned int irqno)
         s3c_irq_unmask((irqno <= (IRQ_EINT7 - EXTINT_OFF)) ? IRQ_EINT4t7 : IRQ_EINT8t23);
 }
 
-static int
+int
 s3c_irqext_type(unsigned int irq, unsigned int type)
 {
         void __iomem *extint_reg;
diff --git a/arch/arm/mach-s3c2410/irq.h b/arch/arm/mach-s3c2410/irq.h
index 4abf0ca14e00..f7cc4c983de5 100644
--- a/arch/arm/mach-s3c2410/irq.h
+++ b/arch/arm/mach-s3c2410/irq.h
@@ -97,3 +97,8 @@ s3c_irqsub_ack(unsigned int irqno, unsigned int parentmask, unsigned int group)
                 __raw_writel(parentmask, S3C2410_INTPND);
         }
 }
+
+/* exported for use in arch/arm/mach-s3c2410 */
+
+extern int s3c_irq_wake(unsigned int irqno, unsigned int state);
+extern int s3c_irqext_type(unsigned int irq, unsigned int type);
diff --git a/arch/arm/mach-s3c2410/s3c2412-irq.c b/arch/arm/mach-s3c2410/s3c2412-irq.c
new file mode 100644
index 000000000000..c80ec93dfea9
--- /dev/null
+++ b/arch/arm/mach-s3c2410/s3c2412-irq.c
@@ -0,0 +1,130 @@
+/* linux/arch/arm/mach-s3c2412/s3c2412-irq.c
+ *
+ * Copyright (c) 2006 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/ptrace.h>
+#include <linux/sysdev.h>
+
+#include <asm/hardware.h>
+#include <asm/irq.h>
+#include <asm/io.h>
+
+#include <asm/mach/irq.h>
+
+#include <asm/arch/regs-irq.h>
+#include <asm/arch/regs-gpio.h>
+
+#include "cpu.h"
+#include "irq.h"
+
+/* the s3c2412 changes the behaviour of IRQ_EINT0 through IRQ_EINT3 by
+ * having them turn up in both the INT* and the EINT* registers. Whilst
+ * both show the status, they both now need to be acked when the IRQs
+ * go off.
+*/
+
+static void
+s3c2412_irq_mask(unsigned int irqno)
+{
+        unsigned long bitval = 1UL << (irqno - IRQ_EINT0);
+        unsigned long mask;
+
+        mask = __raw_readl(S3C2410_INTMSK);
+        __raw_writel(mask | bitval, S3C2410_INTMSK);
+
+        mask = __raw_readl(S3C2412_EINTMASK);
+        __raw_writel(mask | bitval, S3C2412_EINTMASK);
+}
+
+static inline void
+s3c2412_irq_ack(unsigned int irqno)
+{
+        unsigned long bitval = 1UL << (irqno - IRQ_EINT0);
+
+        __raw_writel(bitval, S3C2412_EINTPEND);
+        __raw_writel(bitval, S3C2410_SRCPND);
+        __raw_writel(bitval, S3C2410_INTPND);
+}
+
+static inline void
+s3c2412_irq_maskack(unsigned int irqno)
+{
+        unsigned long bitval = 1UL << (irqno - IRQ_EINT0);
+        unsigned long mask;
+
+        mask = __raw_readl(S3C2410_INTMSK);
+        __raw_writel(mask|bitval, S3C2410_INTMSK);
+
+        mask = __raw_readl(S3C2412_EINTMASK);
+        __raw_writel(mask | bitval, S3C2412_EINTMASK);
+
+        __raw_writel(bitval, S3C2412_EINTPEND);
+        __raw_writel(bitval, S3C2410_SRCPND);
+        __raw_writel(bitval, S3C2410_INTPND);
+}
+
+static void
+s3c2412_irq_unmask(unsigned int irqno)
+{
+        unsigned long bitval = 1UL << (irqno - IRQ_EINT0);
+        unsigned long mask;
+
+        mask = __raw_readl(S3C2412_EINTMASK);
+        __raw_writel(mask & ~bitval, S3C2412_EINTMASK);
+
+        mask = __raw_readl(S3C2410_INTMSK);
+        __raw_writel(mask & ~bitval, S3C2410_INTMSK);
+}
+
+static struct irqchip s3c2412_irq_eint0t4 = {
+        .ack       = s3c2412_irq_ack,
+        .mask      = s3c2412_irq_mask,
+        .unmask    = s3c2412_irq_unmask,
+        .set_wake  = s3c_irq_wake,
+        .set_type  = s3c_irqext_type,
+};
+
+static int s3c2412_irq_add(struct sys_device *sysdev)
+{
+        unsigned int irqno;
+
+        for (irqno = IRQ_EINT0; irqno <= IRQ_EINT3; irqno++) {
+                set_irq_chip(irqno, &s3c2412_irq_eint0t4);
+                set_irq_handler(irqno, do_edge_IRQ);
+                set_irq_flags(irqno, IRQF_VALID);
+        }
+
+        return 0;
+}
+
+static struct sysdev_driver s3c2412_irq_driver = {
+        .add            = s3c2412_irq_add,
+};
+
+static int s3c2412_irq_init(void)
+{
+        return sysdev_driver_register(&s3c2412_sysclass, &s3c2412_irq_driver);
+}
+
+arch_initcall(s3c2412_irq_init);