1 files changed, 60 insertions, 0 deletions
diff --git a/drivers/firmware/google/memconsole.c b/drivers/firmware/google/memconsole.c
new file mode 100644
index 000000000..166f07c68
--- /dev/null
+++ b/drivers/firmware/google/memconsole.c
@@ -0,0 +1,60 @@
+/*
+ * memconsole.c
+ *
+ * Architecture-independent parts of the memory based BIOS console.
+ *
+ * Copyright 2017 Google Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License v2.0 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/init.h>
+#include <linux/sysfs.h>
+#include <linux/kobject.h>
+#include <linux/module.h>
+
+#include "memconsole.h"
+
+static ssize_t (*memconsole_read_func)(char *, loff_t, size_t);
+
+static ssize_t memconsole_read(struct file *filp, struct kobject *kobp,
+			       struct bin_attribute *bin_attr, char *buf,
+			       loff_t pos, size_t count)
+{
+	if (WARN_ON_ONCE(!memconsole_read_func))
+		return -EIO;
+	return memconsole_read_func(buf, pos, count);
+}
+
+static struct bin_attribute memconsole_bin_attr = {
+	.attr = {.name = "log", .mode = 0444},
+	.read = memconsole_read,
+};
+
+void memconsole_setup(ssize_t (*read_func)(char *, loff_t, size_t))
+{
+	memconsole_read_func = read_func;
+}
+EXPORT_SYMBOL(memconsole_setup);
+
+int memconsole_sysfs_init(void)
+{
+	return sysfs_create_bin_file(firmware_kobj, &memconsole_bin_attr);
+}
+EXPORT_SYMBOL(memconsole_sysfs_init);
+
+void memconsole_exit(void)
+{
+	sysfs_remove_bin_file(firmware_kobj, &memconsole_bin_attr);
+}
+EXPORT_SYMBOL(memconsole_exit);
+
+MODULE_AUTHOR("Google, Inc.");
+MODULE_LICENSE("GPL");