mmrm: Implement debugfs and logging levels

Use debug_level file in debugfs to set
logging level.

Change-Id: I1e378437039ceb59c44ff51f4eb6240804aa5f53

driver/src/mmrm_debug.c

@@ -2,14 +2,97 @@
 /*
  * Copyright (c) 2020, The Linux Foundation. All rights reserved.
  */
+
+#include <linux/slab.h>
+
 #include "mmrm_debug.h"
 
+int msm_mmrm_debug = MMRM_ERR | MMRM_PRINTK;
+
+#define MAX_DBG_BUF_SIZE 4096
+
+static ssize_t msm_mmrm_debugfs_info_read(struct file *file,
+	char __user *buf,
+	size_t count,
+	loff_t *ppos)
+{
+	char *dbuf, *cur, *end;
+	ssize_t len = 0;
+
+	dbuf = kzalloc(MAX_DBG_BUF_SIZE, GFP_KERNEL);
+	if (!dbuf)
+	{
+		d_mpr_e("%s: Allocation failed!\n", __func__);
+		return -ENOMEM;
+	}
+	cur = dbuf;
+	end = cur + MAX_DBG_BUF_SIZE;
+
+	// TODO: Fill cur here
+
+	len = simple_read_from_buffer(buf, count, ppos, dbuf, cur - dbuf);
+	kfree(dbuf);
+	return len;
+}
+
+const struct file_operations msm_mmrm_debugfs_info_fops = {
+	.open = simple_open,
+	.read = msm_mmrm_debugfs_info_read,
+};
+
 struct dentry *msm_mmrm_debugfs_init(void)
 {
+	struct dentry *dir;
+	int file_val;
+	bool ok = false;
+
+	d_mpr_h("%s: entering\n", __func__);
+
+	/* create a directory in debugfs root (/sys/kernel/debug) */
+	dir = debugfs_create_dir("msm_mmrm", NULL);
+	if (IS_ERR_OR_NULL(dir))
+	{
+		d_mpr_e("%s: Call to debugfs_create_dir(%s) failed!\n", __func__, "mmrm");
+		goto failed_create_dir;
+	}
+
+	/* basic info */
+	if (!debugfs_create_file("info", 0444, dir, &file_val, &msm_mmrm_debugfs_info_fops))
+	{
+		d_mpr_e("%s: Call to debugfs_create_file(%s) failed!\n", __func__, "info");
+		goto failed_create_dir;
+	}
+
+#define __debugfs_create(__type, __name, __value) ({ \
+	struct dentry *f = debugfs_create_##__type(__name, 0644, dir, __value); \
+	if (IS_ERR_OR_NULL(f)) { \
+		d_mpr_e("%s: Failed creating debugfs file '%pd/%s'\n", \
+			__func__, dir, __name); \
+		f = NULL; \
+	} \
+	f; \
+})
+
+	/* add other params here */
+	ok =
+	__debugfs_create(u32, "debug_level", &msm_mmrm_debug);
+
+#undef __debugfs_create
+
+	if (!ok)
+		goto failed_create_dir;
+
+	d_mpr_h("%s: exiting\n", __func__);
+	return dir;
+
+failed_create_dir:
+	d_mpr_h("%s: error exit\n", __func__);
 	return NULL;
 }
 
-void msm_mmrm_debugfs_deinit(void)
+void msm_mmrm_debugfs_deinit(struct dentry *dir)
 {
+	d_mpr_h("%s: entering\n", __func__);
+	debugfs_remove_recursive(dir);
+	d_mpr_h("%s: exiting\n", __func__);
 }
-