1 files changed, 92 insertions, 0 deletions
diff --git a/drivers/auxdisplay/line-display.h b/drivers/auxdisplay/line-display.h
new file mode 100644
index 000000000000..36853b639711
--- /dev/null
+++ b/drivers/auxdisplay/line-display.h
@@ -0,0 +1,92 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Character line display core support
+ *
+ * Copyright (C) 2016 Imagination Technologies
+ * Author: Paul Burton <paul.burton@mips.com>
+ *
+ * Copyright (C) 2021 Glider bv
+ * Copyright (C) 2025 Jean-François Lessard
+ */
+
+#ifndef _LINEDISP_H
+#define _LINEDISP_H
+
+#include <linux/device.h>
+#include <linux/timer_types.h>
+
+#include <linux/map_to_7segment.h>
+#include <linux/map_to_14segment.h>
+
+struct linedisp;
+
+/**
+ * enum linedisp_map_type - type of the character mapping
+ * @LINEDISP_MAP_SEG7: Map characters to 7 segment display
+ * @LINEDISP_MAP_SEG14: Map characters to 14 segment display
+ */
+enum linedisp_map_type {
+	LINEDISP_MAP_SEG7,
+	LINEDISP_MAP_SEG14,
+};
+
+/**
+ * struct linedisp_map - character mapping
+ * @type: type of the character mapping
+ * @map: conversion character mapping
+ * @size: size of the @map
+ */
+struct linedisp_map {
+	enum linedisp_map_type type;
+	union {
+		struct seg7_conversion_map seg7;
+		struct seg14_conversion_map seg14;
+	} map;
+	unsigned int size;
+};
+
+/**
+ * struct linedisp_ops - character line display operations
+ * @get_map_type: Function called to get the character mapping, if required
+ * @update: Function called to update the display. This must not sleep!
+ */
+struct linedisp_ops {
+	int (*get_map_type)(struct linedisp *linedisp);
+	void (*update)(struct linedisp *linedisp);
+};
+
+/**
+ * struct linedisp - character line display private data structure
+ * @dev: the line display device
+ * @timer: timer used to implement scrolling
+ * @ops: character line display operations
+ * @buf: pointer to the buffer for the string currently displayed
+ * @message: the full message to display or scroll on the display
+ * @num_chars: the number of characters that can be displayed
+ * @message_len: the length of the @message string
+ * @scroll_pos: index of the first character of @message currently displayed
+ * @scroll_rate: scroll interval in jiffies
+ * @id: instance id of this display
+ */
+struct linedisp {
+	struct device dev;
+	struct timer_list timer;
+	const struct linedisp_ops *ops;
+	struct linedisp_map *map;
+	char *buf;
+	char *message;
+	unsigned int num_chars;
+	unsigned int message_len;
+	unsigned int scroll_pos;
+	unsigned int scroll_rate;
+	unsigned int id;
+};
+
+int linedisp_attach(struct linedisp *linedisp, struct device *dev,
+		    unsigned int num_chars, const struct linedisp_ops *ops);
+void linedisp_detach(struct device *dev);
+int linedisp_register(struct linedisp *linedisp, struct device *parent,
+		      unsigned int num_chars, const struct linedisp_ops *ops);
+void linedisp_unregister(struct linedisp *linedisp);
+
+#endif /* LINEDISP_H */