File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/kernel/irq/dummychip.c b/kernel/irq/dummychip.c
new file mode 100644
index 0000000..326a67f
--- /dev/null
+++ b/kernel/irq/dummychip.c
@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
+ * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
+ *
+ * This file contains the dummy interrupt chip implementation
+ */
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/export.h>
+
+#include "internals.h"
+
+/*
+ * What should we do if we get a hw irq event on an illegal vector?
+ * Each architecture has to answer this themself.
+ */
+static void ack_bad(struct irq_data *data)
+{
+ struct irq_desc *desc = irq_data_to_desc(data);
+
+ print_irq_desc(data->irq, desc);
+ ack_bad_irq(data->irq);
+}
+
+/*
+ * NOP functions
+ */
+static void noop(struct irq_data *data) { }
+
+static unsigned int noop_ret(struct irq_data *data)
+{
+ return 0;
+}
+
+/*
+ * Generic no controller implementation
+ */
+struct irq_chip no_irq_chip = {
+ .name = "none",
+ .irq_startup = noop_ret,
+ .irq_shutdown = noop,
+ .irq_enable = noop,
+ .irq_disable = noop,
+ .irq_ack = ack_bad,
+ .flags = IRQCHIP_SKIP_SET_WAKE,
+};
+
+/*
+ * Generic dummy implementation which can be used for
+ * real dumb interrupt sources
+ */
+struct irq_chip dummy_irq_chip = {
+ .name = "dummy",
+ .irq_startup = noop_ret,
+ .irq_shutdown = noop,
+ .irq_enable = noop,
+ .irq_disable = noop,
+ .irq_ack = noop,
+ .irq_mask = noop,
+ .irq_unmask = noop,
+ .flags = IRQCHIP_SKIP_SET_WAKE,
+};
+EXPORT_SYMBOL_GPL(dummy_irq_chip);