[ARM] 4596/1: S3C2412: Correct IRQs for SDI+CF and add decoding support

Fix the IRQ numbers of the CF and SDI interface on the S3C2412
and S3C2413. Add support to handle these IRQs properly and
ensure that the SDI controller platform device is correctly
renumbered.

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

1 files changed, 58 insertions, 0 deletions

diff --git a/arch/arm/mach-s3c2412/irq.c b/arch/arm/mach-s3c2412/irq.c
index f0d66828f965..e9d0c769f5da 100644
--- a/arch/arm/mach-s3c2412/irq.c
+++ b/arch/arm/mach-s3c2412/irq.c
@@ -38,6 +38,9 @@
 #include <asm/plat-s3c24xx/irq.h>
 #include <asm/plat-s3c24xx/pm.h>
 
+#define INTMSK(start, end) ((1 << ((end) + 1 - (start))) - 1)
+#define INTMSK_SUB(start, end) (INTMSK(start, end) << ((start - S3C2410_IRQSUB(0))))
+
 /* 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
@@ -105,6 +108,51 @@ static struct irq_chip s3c2412_irq_eint0t4 = {
         .set_type  = s3c_irqext_type,
 };
 
+#define INTBIT(x)       (1 << ((x) - S3C2410_IRQSUB(0)))
+
+/* CF and SDI sub interrupts */
+
+static void s3c2412_irq_demux_cfsdi(unsigned int irq, struct irq_desc *desc)
+{
+        unsigned int subsrc, submsk;
+
+        subsrc = __raw_readl(S3C2410_SUBSRCPND);
+        submsk = __raw_readl(S3C2410_INTSUBMSK);
+
+        subsrc  &= ~submsk;
+
+        if (subsrc & INTBIT(IRQ_S3C2412_SDI))
+                desc_handle_irq(IRQ_S3C2412_SDI, irq_desc + IRQ_S3C2412_SDI);
+
+        if (subsrc & INTBIT(IRQ_S3C2412_CF))
+                desc_handle_irq(IRQ_S3C2412_CF, irq_desc + IRQ_S3C2412_CF);
+}
+
+#define INTMSK_CFSDI    (1UL << (IRQ_S3C2412_CFSDI - IRQ_EINT0))
+#define SUBMSK_CFSDI    INTMSK_SUB(IRQ_S3C2412_SDI, IRQ_S3C2412_CF)
+
+static void s3c2412_irq_cfsdi_mask(unsigned int irqno)
+{
+        s3c_irqsub_mask(irqno, INTMSK_CFSDI, SUBMSK_CFSDI);
+}
+
+static void s3c2412_irq_cfsdi_unmask(unsigned int irqno)
+{
+        s3c_irqsub_unmask(irqno, INTMSK_CFSDI);
+}
+
+static void s3c2412_irq_cfsdi_ack(unsigned int irqno)
+{
+        s3c_irqsub_maskack(irqno, INTMSK_CFSDI, SUBMSK_CFSDI);
+}
+
+static struct irq_chip s3c2412_irq_cfsdi = {
+        .name           = "s3c2412-cfsdi",
+        .ack            = s3c2412_irq_cfsdi_ack,
+        .mask           = s3c2412_irq_cfsdi_mask,
+        .unmask         = s3c2412_irq_cfsdi_unmask,
+};
+
 static int s3c2412_irq_add(struct sys_device *sysdev)
 {
         unsigned int irqno;
@@ -115,6 +163,16 @@ static int s3c2412_irq_add(struct sys_device *sysdev)
                 set_irq_flags(irqno, IRQF_VALID);
         }
 
+        /* add demux support for CF/SDI */
+
+        set_irq_chained_handler(IRQ_S3C2412_CFSDI, s3c2412_irq_demux_cfsdi);
+
+        for (irqno = IRQ_S3C2412_SDI; irqno <= IRQ_S3C2412_CF; irqno++) {
+                set_irq_chip(irqno, &s3c2412_irq_cfsdi);
+                set_irq_handler(irqno, handle_level_irq);
+                set_irq_flags(irqno, IRQF_VALID);
+        }
+
         return 0;
 }