kgdb: Add request_irq() to the io ops table for kgdboc

Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>

1 files changed, 36 insertions, 0 deletions

diff --git a/drivers/tty/serial/kgdboc.c b/drivers/tty/serial/kgdboc.c
index a260cde743e2..d6ef160a40a9 100644
--- a/drivers/tty/serial/kgdboc.c
+++ b/drivers/tty/serial/kgdboc.c
@@ -20,6 +20,7 @@
 #include <linux/vt_kern.h>
 #include <linux/input.h>
 #include <linux/module.h>
+#include <linux/interrupt.h>
 
 #define MAX_CONFIG_LEN		40
 
@@ -304,12 +305,47 @@ static void kgdboc_post_exp_handler(void)
 	kgdboc_restore_input();
 }
 
+static int kgdb_tty_irq;
+
+static int kgdboc_request_irq(irq_handler_t fn, unsigned long irqflags,
+			      void *dev_id)
+{
+	int irq, res;
+
+	/* Better to avoid double allocation in the tty driver! */
+	if (kgdb_tty_irq)
+		return 0;
+
+	if (!kgdb_tty_driver->ops->poll_get_irq)
+		return -ENODEV;
+
+	irq =
+	    kgdb_tty_driver->ops->poll_get_irq(kgdb_tty_driver, kgdb_tty_line);
+	if (irq <= 0)
+		return irq ? irq : -ENODEV;
+
+	/*
+	 * TODO: The poll_get_irq() API is bogus because we do
+	 * not
+	 *       have any way to undo things on failure to
+	 * request
+	 *       the IRQ.
+	 */
+	res = request_irq(irq, fn, irqflags, "kgdboc", dev_id);
+	if (res)
+		return res;
+
+	kgdb_tty_irq = irq;
+	return 0;
+}
+
 static struct kgdb_io kgdboc_io_ops = {
 	.name			= "kgdboc",
 	.read_char		= kgdboc_get_char,
 	.write_char		= kgdboc_put_char,
 	.pre_exception		= kgdboc_pre_exp_handler,
 	.post_exception		= kgdboc_post_exp_handler,
+	.request_irq		= kgdboc_request_irq,
 };
 
 #ifdef CONFIG_KGDB_SERIAL_CONSOLE