linux/drivers/auxdisplay/line-display.h
Andy Shevchenko 50d6b9d56e auxdisplay: linedisp: Use unique number for id
The absence of decrementation of linedisp_id is incorrect in two ways,
i.e. it may cause:
- an ID exhaustion
- (and if the above is addressed) a duplicate id number may be allocated
  next time a device is added

Replace above mentioned approach by using IDA framework.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-15 13:31:12 +02:00

46 lines
1.3 KiB
C

/* 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
*/
#ifndef _LINEDISP_H
#define _LINEDISP_H
/**
* struct linedisp - character line display private data structure
* @dev: the line display device
* @timer: timer used to implement scrolling
* @update: function called to update the display
* @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;
void (*update)(struct linedisp *linedisp);
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_register(struct linedisp *linedisp, struct device *parent,
unsigned int num_chars, char *buf,
void (*update)(struct linedisp *linedisp));
void linedisp_unregister(struct linedisp *linedisp);
#endif /* LINEDISP_H */