1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * memconsole.c
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Architecture-independent parts of the memory based BIOS console.
6*4882a593Smuzhiyun *
7*4882a593Smuzhiyun * Copyright 2017 Google Inc.
8*4882a593Smuzhiyun */
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun #include <linux/sysfs.h>
11*4882a593Smuzhiyun #include <linux/kobject.h>
12*4882a593Smuzhiyun #include <linux/module.h>
13*4882a593Smuzhiyun
14*4882a593Smuzhiyun #include "memconsole.h"
15*4882a593Smuzhiyun
memconsole_read(struct file * filp,struct kobject * kobp,struct bin_attribute * bin_attr,char * buf,loff_t pos,size_t count)16*4882a593Smuzhiyun static ssize_t memconsole_read(struct file *filp, struct kobject *kobp,
17*4882a593Smuzhiyun struct bin_attribute *bin_attr, char *buf,
18*4882a593Smuzhiyun loff_t pos, size_t count)
19*4882a593Smuzhiyun {
20*4882a593Smuzhiyun ssize_t (*memconsole_read_func)(char *, loff_t, size_t);
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun memconsole_read_func = bin_attr->private;
23*4882a593Smuzhiyun if (WARN_ON_ONCE(!memconsole_read_func))
24*4882a593Smuzhiyun return -EIO;
25*4882a593Smuzhiyun
26*4882a593Smuzhiyun return memconsole_read_func(buf, pos, count);
27*4882a593Smuzhiyun }
28*4882a593Smuzhiyun
29*4882a593Smuzhiyun static struct bin_attribute memconsole_bin_attr = {
30*4882a593Smuzhiyun .attr = {.name = "log", .mode = 0444},
31*4882a593Smuzhiyun .read = memconsole_read,
32*4882a593Smuzhiyun };
33*4882a593Smuzhiyun
memconsole_setup(ssize_t (* read_func)(char *,loff_t,size_t))34*4882a593Smuzhiyun void memconsole_setup(ssize_t (*read_func)(char *, loff_t, size_t))
35*4882a593Smuzhiyun {
36*4882a593Smuzhiyun memconsole_bin_attr.private = read_func;
37*4882a593Smuzhiyun }
38*4882a593Smuzhiyun EXPORT_SYMBOL(memconsole_setup);
39*4882a593Smuzhiyun
memconsole_sysfs_init(void)40*4882a593Smuzhiyun int memconsole_sysfs_init(void)
41*4882a593Smuzhiyun {
42*4882a593Smuzhiyun return sysfs_create_bin_file(firmware_kobj, &memconsole_bin_attr);
43*4882a593Smuzhiyun }
44*4882a593Smuzhiyun EXPORT_SYMBOL(memconsole_sysfs_init);
45*4882a593Smuzhiyun
memconsole_exit(void)46*4882a593Smuzhiyun void memconsole_exit(void)
47*4882a593Smuzhiyun {
48*4882a593Smuzhiyun sysfs_remove_bin_file(firmware_kobj, &memconsole_bin_attr);
49*4882a593Smuzhiyun }
50*4882a593Smuzhiyun EXPORT_SYMBOL(memconsole_exit);
51*4882a593Smuzhiyun
52*4882a593Smuzhiyun MODULE_AUTHOR("Google, Inc.");
53*4882a593Smuzhiyun MODULE_LICENSE("GPL");
54