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authorLinus Walleij <linusw@kernel.org>2026-06-30 18:05:56 +0100
committerRussell King <rmk+kernel@armlinux.org.uk>2026-08-05 16:48:11 +0100
commitbb3b2cfeb206f5b10b859e134651b54120e3f530 (patch)
tree6717fcea088ba5c5f15002a48101fa2537135bf2 /drivers/char/nwbutton.h
downloadlinux-stable-bb3b2cfeb206f5b10b859e134651b54120e3f530.tar.gz
linux-stable-bb3b2cfeb206f5b10b859e134651b54120e3f530.zip
ARM: 9480/1: entry: expand comment in __switch_tografted
As per discussion between the developers in the mail thread linked, expand the comment in __switch_to so that readers of the code understand what is going on. Suggested-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Linus Walleij <linusw@kernel.org>> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Diffstat (limited to 'drivers/char/nwbutton.h')
-rw-r--r--drivers/char/nwbutton.h40
1 files changed, 40 insertions, 0 deletions
diff --git a/drivers/char/nwbutton.h b/drivers/char/nwbutton.h
new file mode 100644
index 000000000..f2b9fdc1f
--- /dev/null
+++ b/drivers/char/nwbutton.h
@@ -0,0 +1,40 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __NWBUTTON_H
+#define __NWBUTTON_H
+
+/*
+ * NetWinder Button Driver-
+ * Copyright (C) Alex Holden <alex@linuxhacker.org> 1998, 1999.
+ */
+
+#ifdef __NWBUTTON_C /* Actually compiling the driver itself */
+
+/* Various defines: */
+
+#define NUM_PRESSES_REBOOT 2 /* How many presses to activate shutdown */
+#define BUTTON_DELAY 30 /* How many jiffies for sequence to end */
+#define VERSION "0.3" /* Driver version number */
+
+/* Structure definitions: */
+
+struct button_callback {
+ void (*callback) (void);
+ int count;
+};
+
+/* Function prototypes: */
+
+static void button_sequence_finished(struct timer_list *unused);
+static irqreturn_t button_handler (int irq, void *dev_id);
+int button_init (void);
+int button_add_callback (void (*callback) (void), int count);
+int button_del_callback (void (*callback) (void));
+static void button_consume_callbacks (int bpcount);
+
+#else /* Not compiling the driver itself */
+
+extern int button_add_callback (void (*callback) (void), int count);
+extern int button_del_callback (void (*callback) (void));
+
+#endif /* __NWBUTTON_C */
+#endif /* __NWBUTTON_H */