1 files changed, 89 insertions, 0 deletions
diff --git a/arch/arm/plat-samsung/irq-uart.c b/arch/arm/plat-samsung/irq-uart.c
new file mode 100644
index 00000000..657405c4
--- /dev/null
+++ b/arch/arm/plat-samsung/irq-uart.c
@@ -0,0 +1,89 @@
+/* arch/arm/plat-samsung/irq-uart.c
+ *	originally part of arch/arm/plat-s3c64xx/irq.c
+ *
+ * Copyright 2008 Openmoko, Inc.
+ * Copyright 2008 Simtec Electronics
+ *      Ben Dooks <ben@simtec.co.uk>
+ *      http://armlinux.simtec.co.uk/
+ *
+ * Samsung- UART Interrupt handling
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/serial_core.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+
+#include <mach/map.h>
+#include <plat/irq-uart.h>
+#include <plat/regs-serial.h>
+#include <plat/cpu.h>
+
+/* Note, we make use of the fact that the parent IRQs, IRQ_UART[0..3]
+ * are consecutive when looking up the interrupt in the demux routines.
+ */
+static void s3c_irq_demux_uart(unsigned int irq, struct irq_desc *desc)
+{
+	struct s3c_uart_irq *uirq = desc->irq_data.handler_data;
+	u32 pend = __raw_readl(uirq->regs + S3C64XX_UINTP);
+	int base = uirq->base_irq;
+
+	if (pend & (1 << 0))
+		generic_handle_irq(base);
+	if (pend & (1 << 1))
+		generic_handle_irq(base + 1);
+	if (pend & (1 << 2))
+		generic_handle_irq(base + 2);
+	if (pend & (1 << 3))
+		generic_handle_irq(base + 3);
+}
+
+static void __init s3c_init_uart_irq(struct s3c_uart_irq *uirq)
+{
+	void __iomem *reg_base = uirq->regs;
+	struct irq_chip_generic *gc;
+	struct irq_chip_type *ct;
+
+	/* mask all interrupts at the start. */
+	__raw_writel(0xf, reg_base + S3C64XX_UINTM);
+
+	gc = irq_alloc_generic_chip("s3c-uart", 1, uirq->base_irq, reg_base,
+				    handle_level_irq);
+
+	if (!gc) {
+		pr_err("%s: irq_alloc_generic_chip for IRQ %u failed\n",
+		       __func__, uirq->base_irq);
+		return;
+	}
+
+	ct = gc->chip_types;
+	ct->chip.irq_ack = irq_gc_ack_set_bit;
+	ct->chip.irq_mask = irq_gc_mask_set_bit;
+	ct->chip.irq_unmask = irq_gc_mask_clr_bit;
+	ct->regs.ack = S3C64XX_UINTP;
+	ct->regs.mask = S3C64XX_UINTM;
+	irq_setup_generic_chip(gc, IRQ_MSK(4), IRQ_GC_INIT_MASK_CACHE,
+			       IRQ_NOREQUEST | IRQ_NOPROBE, 0);
+
+	irq_set_handler_data(uirq->parent_irq, uirq);
+	irq_set_chained_handler(uirq->parent_irq, s3c_irq_demux_uart);
+}
+
+/**
+ * s3c_init_uart_irqs() - initialise UART IRQs and the necessary demuxing
+ * @irq: The interrupt data for registering
+ * @nr_irqs: The number of interrupt descriptions in @irq.
+ *
+ * Register the UART interrupts specified by @irq including the demuxing
+ * routines. This supports the S3C6400 and newer style of devices.
+ */
+void __init s3c_init_uart_irqs(struct s3c_uart_irq *irq, unsigned int nr_irqs)
+{
+	for (; nr_irqs > 0; nr_irqs--, irq++)
+		s3c_init_uart_irq(irq);
+}