// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2019 MediaTek Inc.
 */

#ifdef pr_fmt
#undef pr_fmt
#endif
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/version.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kobject.h>
#include "mt-plat/mtk_thermal_monitor.h"


#include <linux/version.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/uaccess.h>
#include <linux/pid.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/uidgid.h>

#define MAX_LEN	256

#if 1
#define mtk_thermal_policy_dprintk(fmt, args...)	\
	pr_notice("thermal/thermal_policy " fmt, ##args)
#else
#define mtk_thermal_policy_dprintk(fmt, args...)
#endif

#define TM_CLIENT_chgpolicy 4


static unsigned int tm_pid;
static unsigned int tm_input_pid;
static struct task_struct *pg_task;
static kuid_t uid = KUIDT_INIT(0);
static kgid_t gid = KGIDT_INIT(1000);

static ssize_t _mtk_tp_pid_write
(struct file *filp, const char __user *buf, size_t len, loff_t *data)
{
	int ret = 0;
	char tmp[MAX_LEN] = { 0 };

	len = (len < (MAX_LEN - 1)) ? len : (MAX_LEN - 1);
	/* write data to the buffer */
	if (copy_from_user(tmp, buf, len))
		return -EFAULT;

	ret = kstrtouint(tmp, 10, &tm_input_pid);
	if (ret)
		WARN_ON_ONCE(1);

	mtk_thermal_policy_dprintk("%s %s = %d\n", __func__, tmp,
			tm_input_pid);

	return len;
}

static int _mtk_tp_pid_read(struct seq_file *m, void *v)
{
	seq_printf(m, "%d\n", tm_input_pid);
	mtk_thermal_policy_dprintk("%s %d\n", __func__, tm_input_pid);

	return 0;
}

static int _mtk_tp_pid_open(struct inode *inode, struct file *file)
{
	return single_open(file, _mtk_tp_pid_read, PDE_DATA(inode));
}

static const struct file_operations _tp_pid_fops = {
	.owner = THIS_MODULE,
	.open = _mtk_tp_pid_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.write = _mtk_tp_pid_write,
	.release = single_release,
};


static int _mtk_cl_sd_send_signal(int val)
{
	int ret = 0;

	if (tm_input_pid == 0) {
		mtk_thermal_policy_dprintk("%s pid is empty\n", __func__);
		ret = -1;
	}

	mtk_thermal_policy_dprintk("%s pid is %d, %d, 0x%x\n", __func__,
			tm_pid, tm_input_pid, val);

	if (ret == 0 && tm_input_pid != tm_pid) {
		tm_pid = tm_input_pid;

		if (pg_task != NULL)
			put_task_struct(pg_task);
		pg_task = get_pid_task(find_vpid(tm_pid), PIDTYPE_PID);
	}

	if (ret == 0 && pg_task) {
		siginfo_t info;

		info.si_signo = SIGIO;
		info.si_errno = TM_CLIENT_chgpolicy;
		info.si_code = val;
		info.si_addr = NULL;
		ret = send_sig_info(SIGIO, &info, pg_task);
	}

	if (ret != 0)
		mtk_thermal_policy_dprintk("%s ret=%d\n", __func__, ret);

	return ret;
}


int mtk_change_thermal_policy(int tp_index, int onoff)
{
	int ret = 0;
	int mix_val = 0;

	mix_val = (onoff << 8) | tp_index;

	mtk_thermal_policy_dprintk("%s tp_index=%d, onoff=%d, mix_val=0x%3x\n",
		__func__, tp_index, onoff, mix_val);

	ret = _mtk_cl_sd_send_signal(mix_val);

	return ret;
}


static int tp_idx;
static int tp_onoff;

static ssize_t _mtk_tp_test_write
(struct file *filp, const char __user *buf, size_t len, loff_t *data)
{
	char tmp[128] = { 0 };
	int idx, onoff;

	mtk_thermal_policy_dprintk("%s 1\n", __func__);

	len = (len < (128 - 1)) ? len : (128 - 1);
	/* write data to the buffer */
	if (copy_from_user(tmp, buf, len))
		return -EFAULT;

	mtk_thermal_policy_dprintk("%s 2\n", __func__);


	if (data == NULL) {
		mtk_thermal_policy_dprintk("%s null data\n", __func__);
		return -EINVAL;
	}

	if (sscanf(tmp, "%d %d", &idx, &onoff)  >= 1) {
		tp_idx = idx;
		tp_onoff = onoff;
		mtk_thermal_policy_dprintk("%s idx: %d, enable:%d\n",
			__func__, tp_idx, tp_onoff);

		return len;
	}

	mtk_thermal_policy_dprintk("%s : bad argument\n", __func__);
	return -EINVAL;

}

static int _mtk_tp_test_read(struct seq_file *m, void *v)
{
	mtk_thermal_policy_dprintk("%s %d, %d\n",
		__func__, tp_idx, tp_onoff);
	mtk_change_thermal_policy(tp_idx, tp_onoff);
	return 0;
}

static int _mtk_tp_test_open(struct inode *inode, struct file *file)
{
	return single_open(file, _mtk_tp_test_read, PDE_DATA(inode));
}

static const struct file_operations _tp_test_fops = {
	.owner = THIS_MODULE,
	.open = _mtk_tp_test_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.write = _mtk_tp_test_write,
	.release = single_release,
};





static int __init mtk_thermal_policy_init(void)
{
	struct proc_dir_entry *entry = NULL;
	struct proc_dir_entry *dir_entry
		= mtk_thermal_get_proc_drv_therm_dir_entry();

	mtk_thermal_policy_dprintk("init\n");

	if (!dir_entry) {
		mtk_thermal_policy_dprintk(
		"%s mkdir /proc/driver/thermal failed\n", __func__);
		return -1;
	}

	entry =
		proc_create("tp_pid", 0664,
				dir_entry,
				&_tp_pid_fops);
	if (!entry)
		mtk_thermal_policy_dprintk(
			"%s tp_pid creation failed\n", __func__);
	else
		proc_set_user(entry, uid, gid);


	entry =
		proc_create("tp_test", 0664,
				dir_entry,
				&_tp_test_fops);
	if (!entry)
		mtk_thermal_policy_dprintk(
			"%s _tp_test_fops creation failed\n", __func__);
	else
		proc_set_user(entry, uid, gid);

	return 0;
}

static void __exit mtk_thermal_policy_exit(void)
{
	mtk_thermal_policy_dprintk("exit\n");
}
module_init(mtk_thermal_policy_init);
module_exit(mtk_thermal_policy_exit);