1 files changed, 165 insertions, 0 deletions
diff --git a/drivers/net/ethernet/marvell/octeontx2/bphy/otx2_bphy_debugfs.c b/drivers/net/ethernet/marvell/octeontx2/bphy/otx2_bphy_debugfs.c
new file mode 100644
index 000000000000..a2d03352c89d
--- /dev/null
+++ b/drivers/net/ethernet/marvell/octeontx2/bphy/otx2_bphy_debugfs.c
@@ -0,0 +1,165 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Marvell OcteonTx2 BPHY RFOE/CPRI Ethernet Driver
+ *
+ * Copyright (C) 2021 Marvell International Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/debugfs.h>
+
+#include "otx2_bphy_debugfs.h"
+#include "otx2_bphy.h"
+
+#define OTX2_BPHY_DEBUGFS_MODE 0400
+
+struct otx2_bphy_debugfs_reader_info {
+	atomic_t			refcnt;
+	size_t				buffer_size;
+	void				*priv;
+	otx2_bphy_debugfs_reader	reader;
+	struct dentry			*entry;
+	char				buffer[1];
+};
+
+static struct dentry *otx2_bphy_debugfs;
+
+static int otx2_bphy_debugfs_open(struct inode *inode, struct file *file);
+
+static int otx2_bphy_debugfs_release(struct inode *inode, struct file *file);
+
+static ssize_t otx2_bphy_debugfs_read(struct file *file, char __user *buffer,
+				      size_t count, loff_t *offset);
+
+static const struct file_operations otx2_bphy_debugfs_foper = {
+	.owner		= THIS_MODULE,
+	.open		= otx2_bphy_debugfs_open,
+	.release	= otx2_bphy_debugfs_release,
+	.read		= otx2_bphy_debugfs_read,
+};
+
+void __init otx2_bphy_debugfs_init(void)
+{
+	otx2_bphy_debugfs = debugfs_create_dir(DRV_NAME, NULL);
+	if (!otx2_bphy_debugfs)
+		pr_info("%s: debugfs is not enabled\n", DRV_NAME);
+}
+
+void *otx2_bphy_debugfs_add_file(const char *name,
+				 size_t buffer_size,
+				 void *priv,
+				 otx2_bphy_debugfs_reader reader)
+{
+	struct otx2_bphy_debugfs_reader_info *info = NULL;
+	size_t total_size = 0;
+
+	if (!otx2_bphy_debugfs) {
+		pr_info("%s: debugfs not enabled, ignoring %s\n", DRV_NAME,
+			name);
+		goto out;
+	}
+
+	total_size = buffer_size +
+		offsetof(struct otx2_bphy_debugfs_reader_info,
+			 buffer);
+
+	info = kzalloc(total_size, GFP_KERNEL);
+
+	if (!info)
+		goto out;
+
+	info->buffer_size = buffer_size;
+	info->priv = priv;
+	info->reader = reader;
+
+	atomic_set(&info->refcnt, 0);
+
+	info->entry = debugfs_create_file(name, OTX2_BPHY_DEBUGFS_MODE,
+					  otx2_bphy_debugfs, info,
+					  &otx2_bphy_debugfs_foper);
+
+	if (!info->entry) {
+		pr_err("%s: debugfs failed to add file %s\n", DRV_NAME, name);
+		kfree(info);
+		info = NULL;
+		goto out;
+	}
+
+	pr_info("%s: debugfs created successfully for %s\n", DRV_NAME, name);
+
+out:
+	return info;
+}
+
+void otx2_bphy_debugfs_remove_file(void *entry)
+{
+	struct otx2_bphy_debugfs_reader_info *info = entry;
+
+	debugfs_remove(info->entry);
+
+	kfree(info);
+}
+
+void __exit otx2_bphy_debugfs_exit(void)
+{
+	debugfs_remove_recursive(otx2_bphy_debugfs);
+}
+
+static int otx2_bphy_debugfs_open(struct inode *inode, struct file *file)
+{
+	struct otx2_bphy_debugfs_reader_info *info = NULL;
+
+	info = inode->i_private;
+
+	if (!atomic_cmpxchg(&info->refcnt, 0, 1)) {
+		file->private_data = info;
+		return 0;
+	}
+
+	return -EBUSY;
+}
+
+static int otx2_bphy_debugfs_release(struct inode *inode, struct file *file)
+{
+	struct otx2_bphy_debugfs_reader_info *info = NULL;
+
+	info = inode->i_private;
+
+	atomic_cmpxchg(&info->refcnt, 1, 0);
+
+	return 0;
+}
+
+static ssize_t otx2_bphy_debugfs_read(struct file *file, char __user *buffer,
+				      size_t count, loff_t *offset)
+{
+	struct otx2_bphy_debugfs_reader_info *info = NULL;
+	ssize_t retval = 0;
+
+	info = file->private_data;
+
+	if (!(*offset))
+		info->reader(&info->buffer[0], info->buffer_size, info->priv);
+
+	if (*offset >= info->buffer_size)
+		goto out;
+
+	if (*offset + count > info->buffer_size)
+		count = info->buffer_size - *offset;
+
+	if (copy_to_user((void __user *)buffer, info->buffer + *offset,
+			 count)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	*offset += count;
+	retval = count;
+
+out:
+	return retval;
+}