/*
*  Copyright (c) 2016 MediaTek Inc.
*
*  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.
*
*  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.
*/
#if defined(CONFIG_DEBUG_FS) && (CONFIG_DEBUG_FS == 1)

#include <linux/debugfs.h>
#include <linux/semaphore.h>
#include <linux/slab.h>
#include <linux/skbuff.h>
#include <linux/kref.h>
#include <linux/semaphore.h>
#include <linux/compiler.h>

#include "btmtk_usb_dbgfs.h"
#include "btmtk_usb_main.h"

/**
 * Directory define.,
 * If this functionality enabled you should find specific file in
 *  /sys/kernel/debug/BTDBG_ROOT/
 */
#define BTDBG_ROOT	"mtkbt"
#define BTDBG_DEV	"bt_dev"
#define BTDBG_TRACE	"log_lvl"

#define FS_BUFFER_SIZE 2048
#define MTKBT_MAX_HCI_FRAME_SIZE 1028	/* (BT_MAX_ACL_SIZE + 4) */

struct BTDbg_Func_t {
	const char *name;
	int (*fp)(const char *value, void *dbg_filp);
	const char *doc;
	const char *help;
};

struct BTDbg_FW_Func_t {
	const char *major;
	const char *minor[DBG_FW_MAX_CMD_COUNT];
	const char *cmd[DBG_FW_MAX_CMD_COUNT];
	const char *doc[DBG_FW_MAX_CMD_COUNT];
};

/**
 * Global variable
 */
static struct mtkdbg_data_t *g_mtkbt_dbg;
u8 btmtk_log_lvl = BTMTK_LOG_LEVEL_DEFAULT;

/**
 * Function prototype
 */
static int btmtk_dbgfs_data_alloc(void *dbg_filp);
static void btmtk_dbgfs_data_free(void *dbg_filp);
static int btmtk_dbgfs_fw_func_main(const char *value, void *dbg_filp);
static int btmtk_dbgfs_tx_frame(void *drv_data, const unsigned char *buffer, const unsigned int length);

static int strtol_access_ok(char ch)
{
	if ((ch >= '0' && ch <= '9') || (ch >= 'A' && ch <= 'F')
		|| (ch >= 'a' && ch <= 'f'))
		return 0;

	BTUSB_ERR("wrong char_%c_", ch);

	return -1;
}

static int str_to_u8(const char *ptr)
{
	u8 ret = 0;
	u8 temp_str[3] = { 0 };
	long res = 0;

	temp_str[0] = *ptr;
	temp_str[1] = *(ptr + 1);

	ret = (u8) (kstrtol((char *)temp_str, 16, &res) & 0xff);

	return res;
}

static int str_to_bytes(u8 *cmd_buf, const char *ptr)
{
	int i = 0, j = 0, len = 0;

	len = strlen(ptr);

	while (i < len) {
		if (ptr[i] == ' ' || ptr[i] == '\t' || ptr[i] == '\r'
			|| ptr[i] == '\n') {
			i++;
			continue;
		}

		if ((ptr[i] == '0' && ptr[i + 1] == 'x')
			|| (ptr[0] == '0' && ptr[i + 1] == 'X')) {
			i += 2;
			continue;
		}

		if (strtol_access_ok(ptr[i]) != 0)
			break;

		cmd_buf[j++] = str_to_u8(&ptr[i]);
		i += 2;
	}

	return j;
}

static int btmtk_dbgfs_tx_frame(void *drv_data, const unsigned char *buffer, const unsigned int length)
{
	int retval = -1;

	BTUSB_DBG("%s: hci cmd", __func__);

	if (unlikely(buffer == NULL || length <= 0)) {
		BTUSB_ERR("%s: [hci_buf = %p][length = 0x%x]", __func__, buffer, length);
		return -EFAULT;
	}

	if (drv_data != NULL)
		BTUSB_DBG("%s: [drv_data=%p]", __func__, drv_data);


	switch (buffer[0]) {
	case MTK_HCI_COMMAND_PKT:
		retval = btmtk_usb_meta_send_data(buffer, length);
		break;

	case MTK_HCI_ACLDATA_PKT:
	case MTK_HCI_SCODATA_PKT:
		retval = btmtk_usb_send_data(buffer, length);
		break;

	default:
		BTUSB_ERR("%s: [INVALID PACKAGE TYPE = %d]", __func__, buffer[0]);
		return -EILSEQ;
	}

	BTUSB_DBG("%s: retval = %d", __func__, retval);

	return retval;
}

static int btmtk_dbgfs_tx_hci_data(const char *value, void *dbg_filp)
{
	int length = 0, ret = 0;
	u8 *hci_cmd = NULL;
	struct mtkdbg_data_t *mtkdbg_filp = (struct mtkdbg_data_t *)dbg_filp;

	if (!mtkdbg_filp->hci_buf) {

		BTUSB_ERR("%s: hci buff is null", __func__);
		btmtk_dbgfs_data_alloc(mtkdbg_filp);

		if (!mtkdbg_filp->hci_buf)
			return -1;
	}

	hci_cmd = mtkdbg_filp->hci_buf;

	length = str_to_bytes(hci_cmd, value);

	BTUSB_DBG_RAW(hci_cmd, length, "%s: dump cmd:", __func__);

	if (mtkdbg_filp->drv_data)
		BTUSB_DBG("%s: [mtkdbg_filp->drv_data = %p]", __func__,
			mtkdbg_filp->drv_data);

	ret = btmtk_dbgfs_tx_frame(mtkdbg_filp->drv_data, hci_cmd, length);

	BTUSB_DBG("%s: ret = %d", __func__, ret);

	return length;
}

static struct BTDbg_Func_t dbgfs_func_list[] = {
	{"HCI", btmtk_dbgfs_tx_hci_data, "tx hci data with type only",
		"01 6F FC 05 01 02 01 00 08"},
	{"FW", btmtk_dbgfs_fw_func_main, "set fw to do something", "DUMP"},
	{"", NULL, NULL, NULL}
};

static struct BTDbg_FW_Func_t dbgfs_fw_func_list[] = {
	{ "DUMP", {"1", "2"},
		{"01 6F FC 05 01 02 01 00 08", "02 6F FC 05 01 02 01 00 08"},
		{"tx fw assert cmd from endpoint 0", "tx fw assert cmd from endpoint 2"} },
	{ NULL, {NULL, NULL}, {NULL, NULL}, {NULL, NULL} }
};

static void btmtk_dbgfs_func_usage(struct BTDbg_Func_t *funclp)
{
	int i;

	BTUSB_DBG("Usage:\n\t <command>= value01 value02 ... ");
	for (i = 0; funclp[i].fp; i++)
		BTUSB_DBG("[%s]example:\n \t \t <%s>=<%s>", funclp[i].doc, funclp[i].name, funclp[i].help);

	BTUSB_DBG("<command> should be less than DBG_TAG_MAX_LEN(0x%x) bytes",
		DBG_TAG_MAX_LEN);
	BTUSB_DBG("<value> should be less than FS_BUFFER_SIZE(0x%x) bytes",
		FS_BUFFER_SIZE);
}

static void btmtk_dbgfs_fw_func_usage(struct BTDbg_FW_Func_t *funclp)
{
	int i, j;

	BTUSB_DBG("Usage:\n\t <FW>= value01 value02 ...");
	for (i = 0; funclp[i].major; i++) {
		for (j = 0; j < DBG_FW_MAX_CMD_COUNT; j++) {
			BTUSB_DBG("%s: example:\n \t \t \t \t <FW>=<%s><%s>",
				__func__, funclp[i].major,
				funclp[i].minor[j]);
			BTUSB_DBG("%s: means:[%s]", __func__,
				funclp[i].doc[j]);
			BTUSB_DBG("%s: tx fw cmd [%s]", __func__,
				funclp[i].cmd[j]);
		}
	}
}

static int btmtk_dbgfs_fw_func_main(const char *value, void *dbg_filp)
{
	int i;
	u32 index = 0;
	const char *s2 = value;

	BTUSB_DBG("%s: [FW=%s]", __func__, value);

	while (1) {
		if (dbgfs_fw_func_list[index].major == NULL || value == NULL)
			goto fw_exit;

		s2 = strstr(value, dbgfs_fw_func_list[index].major);

		if (s2 != NULL) {
			for (i = 0; i < DBG_FW_MAX_CMD_COUNT; i++) {
				if (dbgfs_fw_func_list[index].minor[i] ==
					NULL)
					continue;

				if (strstr(s2, dbgfs_fw_func_list[index].minor[i]) != NULL)
					break;
			}

			if (i < DBG_FW_MAX_CMD_COUNT)
				break;
		}
		index++;
	}

	BTUSB_DBG("%s: match [cmd =%s]", __func__,
		dbgfs_fw_func_list[index].cmd[i]);
	btmtk_dbgfs_tx_hci_data(dbgfs_fw_func_list[index].cmd[i], dbg_filp);

	return 0;

fw_exit:
	BTUSB_DBG("%s: [FW=Wrong cmd!] Fail", __func__);
	btmtk_dbgfs_fw_func_usage(dbgfs_fw_func_list);
	return -1;
}

static int btmtk_dbgfs_get_option(char *option)
{
	u32 index = 0;

	while (1) {
		if (strcmp(option, dbgfs_func_list[index].name) == 0)
			return index;

		if (dbgfs_func_list[index].fp == NULL)
			return -1;

		index++;
	}
}

int BTDbg_Func_Entry(void *dbg_filp, u8 *tag, const char *value)
{
	int index;
	int ret = 0;

	if (tag == NULL)
		goto exit;

	index = btmtk_dbgfs_get_option(tag);

	if (index == -1)
		goto exit;

	ret = dbgfs_func_list[index].fp(value, dbg_filp);
	if (ret < 0) {
		BTUSB_ERR("[tag = %s][value = %s], fail", tag, value);
		return -1;
	}

	return 0;
exit:
	btmtk_dbgfs_func_usage(dbgfs_func_list);
	return -1;
}

int btmtk_dbgfs_func_main(const char *value, void *dbg_filp)
{
	static int count_f;
	int val_len = 0, i;
	u8 Tag_param[DBG_TAG_MAX_LEN] = { 0 };
	const char *val_param = NULL;

	if (unlikely(dbg_filp == NULL || value == NULL)) {
		BTUSB_ERR("%s: [flp =0x%p][value = 0x%p] fail", __func__,
			dbg_filp, value);
		return -1;
	}

	count_f++;

	BTUSB_DBG("%s: in count = %d", __func__, count_f);

	val_len = strlen(value);

	val_len = val_len < DBG_TAG_MAX_LEN ? val_len : DBG_TAG_MAX_LEN;

	for (i = 0; i < val_len; i++) {
		if (value[i] != '=')
			Tag_param[i] = value[i];
		else
			break;
	}

	if (i < val_len) {
		val_param = &value[i + 1];
		BTDbg_Func_Entry(dbg_filp, Tag_param, val_param);

	} else {
		btmtk_dbgfs_func_usage(dbgfs_func_list);
	}

	BTUSB_DBG("%s: out = %d", __func__, count_f);
	return 0;
}

static int BTDbg_dev_open(struct inode *inode, struct file *file)
{
	struct mtkdbg_data_t *mtkdbg_filp = NULL;

	BTUSB_DBG("%s: %s/%s open", __func__, BTDBG_ROOT, BTDBG_DEV);

	file->private_data = inode->i_private;

	mtkdbg_filp = (struct mtkdbg_data_t *)file->private_data;

	if (mtkdbg_filp)
		sema_init(&mtkdbg_filp->wr_lock, 1);

	return 0;
}

static int BTDbg_dev_close(struct inode *inode, struct file *filp)
{
	BTUSB_DBG("[%s][%s]close", BTDBG_ROOT, BTDBG_DEV);

	filp->private_data = NULL;

	return 0;
}

ssize_t BTDbg_dev_write(struct file *filp, const char __user *buf,
			size_t count, loff_t *f_pos)
{
	struct mtkdbg_data_t *mtkdbg_filp = (struct mtkdbg_data_t *)filp->private_data;

	if (mtkdbg_filp == NULL) {

		BTUSB_ERR("%s: no mtkbt dgb data", __func__);
		return -ENODEV;
	}

	down(&mtkdbg_filp->wr_lock);

	if (mtkdbg_filp->w_buf == NULL) {
		BTUSB_ERR("%s: no w_buf", __func__);

		btmtk_dbgfs_data_alloc((void *)mtkdbg_filp);

		if (mtkdbg_filp->w_buf == NULL)
			goto wt_exit;
	}

	memset(mtkdbg_filp->w_buf, 0, FS_BUFFER_SIZE);

	if (unlikely(count > FS_BUFFER_SIZE)) {
		BTUSB_WARN("%s: w count(%zu) > FS_BUFFER_SIZE(%d)", __func__, count, FS_BUFFER_SIZE);
		count = FS_BUFFER_SIZE - 1;
	}

	if (count < FS_BUFFER_SIZE)
		mtkdbg_filp->w_buf[count] = 0;

	if (copy_from_user(mtkdbg_filp->w_buf, buf, count) != 0) {
		BTUSB_ERR("[%s][%s]copy_from_user fail", BTDBG_ROOT,
			BTDBG_DEV);
		goto wt_exit;
	}

	BTUSB_DBG("%s: w_buf: %s", __func__, mtkdbg_filp->w_buf);

#if 1
	mtkdbg_filp->w_buf[count] = 0;
	btmtk_dbgfs_func_main(mtkdbg_filp->w_buf, mtkdbg_filp);
#else

	io_len = strlen(mtkdbg_filp->w_buf);

	if (io_len != count)
		BTUSB_WARN("WARN:io_len != count");

	target_len = io_len < 512 ? io_len : 512;

	for (i = 0; i < 512; i++) {
		if (mtkdbg_filp->w_buf[i] != '=')
			parm_tag[i] = mtkdbg_filp->w_buf[i];
		else
			break;
	}
	if (i < 512) {
		pValue = &mtkdbg_filp->w_buf[i + 1];
		BTDbg_Func_Entry(parm_tag, pValue);
	} else {
		BTUSB_WARN("tag len should be less than 512");
		goto wt_exit;
	}
#endif
wt_exit:
	up(&mtkdbg_filp->wr_lock);

	return count;
}

const struct file_operations BTDbg_dev_fops = {
	.open = BTDbg_dev_open,
	.release = BTDbg_dev_close,
	.write = BTDbg_dev_write
};

static int btmtk_dbgfs_data_alloc(void *dbg_filp)
{
	struct mtkdbg_data_t *mtkdbg_filp = (struct mtkdbg_data_t *)dbg_filp;

	if (!mtkdbg_filp) {
		BTUSB_ERR("%s: fail to alloc data for dbg file is null",
			__func__);
		return -1;
	}

	if (!mtkdbg_filp->btmtk_root_entery) {

		BTUSB_ERR("%s: btmtk_root_entery is null", __func__);
		return -1;
	}

	if (!mtkdbg_filp->btmtk_bt_dev_entry)
		mtkdbg_filp->btmtk_bt_dev_entry =
			debugfs_create_file(BTDBG_DEV, 0644,
					mtkdbg_filp->btmtk_root_entery,
					(void *)mtkdbg_filp, &BTDbg_dev_fops);

	if (!mtkdbg_filp->btmtk_trace_entry)
		mtkdbg_filp->btmtk_trace_entry =
			debugfs_create_u8(BTDBG_TRACE, 0644,
					mtkdbg_filp->btmtk_root_entery,
					&btmtk_log_lvl);

	if (mtkdbg_filp->btmtk_bt_dev_entry == NULL
		|| mtkdbg_filp->btmtk_trace_entry == NULL) {

		BTUSB_WARN("[%s = %p], [%s = %p]", BTDBG_DEV,
			mtkdbg_filp->btmtk_bt_dev_entry, BTDBG_TRACE,
			mtkdbg_filp->btmtk_trace_entry);

	}
	if (!mtkdbg_filp->w_buf)
		mtkdbg_filp->w_buf = kmalloc(FS_BUFFER_SIZE, GFP_KERNEL);

	if (!mtkdbg_filp->hci_buf)
		mtkdbg_filp->hci_buf =
			kmalloc(MTKBT_MAX_HCI_FRAME_SIZE, GFP_KERNEL);

	if (mtkdbg_filp->w_buf == NULL || mtkdbg_filp->hci_buf == NULL) {
		BTUSB_WARN("%s: [w_buf = %p][hci_buf = %p]", __func__,
				mtkdbg_filp->w_buf, mtkdbg_filp->hci_buf);
		return -1;
	}

	return 0;
}

static void btmtk_dbgfs_data_free(void *dbg_filp)
{
	struct mtkdbg_data_t *mtkdbg_filp = (struct mtkdbg_data_t *)dbg_filp;

	if (!mtkdbg_filp) {
		BTUSB_ERR("%s: fail to free data for dbg file is null",
			__func__);
		return;
	}

	if (!mtkdbg_filp->btmtk_root_entery) {
		BTUSB_ERR("%s: fail to free for root entry is null", __func__);
		return;
	}

	debugfs_remove(mtkdbg_filp->btmtk_bt_dev_entry);
	mtkdbg_filp->btmtk_bt_dev_entry = NULL;

	debugfs_remove(mtkdbg_filp->btmtk_trace_entry);
	mtkdbg_filp->btmtk_trace_entry = NULL;

	kfree(mtkdbg_filp->w_buf);
	mtkdbg_filp->w_buf = NULL;

	kfree(mtkdbg_filp->hci_buf);
	mtkdbg_filp->hci_buf = NULL;
}

void btmtk_dbgfs_set_drvdata(void *drv_data)
{
	struct mtkdbg_data_t *mtkdbg_filp = g_mtkbt_dbg;

	BTUSB_DBG("%s: enter", __func__);

	if (unlikely(drv_data == NULL)) {

		BTUSB_ERR("%s: fail for drv_data is null", __func__);
		return;
	}

	if (unlikely(mtkdbg_filp == NULL)) {
		BTUSB_ERR("%s: no mtkbt dgb data", __func__);
		return;
	}

	mtkdbg_filp->drv_data = drv_data;
}

void btmtk_dbgfs_remove_drvdata(void)
{
	struct mtkdbg_data_t *mtkdbg_filp = g_mtkbt_dbg;

	BTUSB_DBG("%s: enter", __func__);

	if (unlikely(mtkdbg_filp == NULL)) {
		BTUSB_ERR("%s: no mtkbt dgb data", __func__);
		return;
	}

	mtkdbg_filp->drv_data = NULL;
}

int btmtk_dbgfs_init(void)
{
	struct mtkdbg_data_t *mtkdbg_filp;

	UNUSED(btmtk_usb_table);	/* clear warning */
	BTUSB_DBG("%s", __func__);

	if (g_mtkbt_dbg != NULL)
		BTUSB_WARN("%s: mtkbt dbg is not null, memory leak !", __func__);

	mtkdbg_filp = kzalloc(sizeof(struct mtkdbg_data_t), GFP_KERNEL);

	if (!mtkdbg_filp) {
		BTUSB_ERR("%s: alloc mtk dbg file fail!", __func__);
		return -1;
	}

	mtkdbg_filp->btmtk_root_entery = debugfs_create_dir(BTDBG_ROOT, NULL);

	if (mtkdbg_filp->btmtk_root_entery == NULL) {
		BTUSB_ERR("%s: fail to create dbg root dir !", __func__);
		kfree(mtkdbg_filp);
		return -1;
	}

	sema_init(&mtkdbg_filp->wr_lock, 1);

	g_mtkbt_dbg = mtkdbg_filp;

	btmtk_dbgfs_data_alloc((void *)g_mtkbt_dbg);

	BTUSB_DBG("%s: success", __func__);
	return 0;
}

void btmtk_dbgfs_exit(void)
{

	if (!g_mtkbt_dbg) {
		BTUSB_ERR("%s: fail to exit dbg file is null", __func__);
		return;
	}

	btmtk_dbgfs_data_free((void *)g_mtkbt_dbg);

	debugfs_remove(g_mtkbt_dbg->btmtk_root_entery);	/*(bt_dev_entry); */
	g_mtkbt_dbg->btmtk_root_entery = NULL;

	kfree(g_mtkbt_dbg);
	g_mtkbt_dbg = NULL;

}

#else /* CONFIG_DEBUG_FS */
void btmtk_dbgfs_set_drvdata(void *drv_data)
{
}

void btmtk_dbgfs_remove_drvdata(void)
{
}

int btmtk_dbgfs_init(void)
{
	BTUSB_INFO("%s: debugfs is not enable now", __func__);
	return 0;
}

void btmtk_dbgfs_exit(void)
{
}

#endif /* CONFIG_DEBUG_FS */