kernel_samsung_a34x-permissive/drivers/misc/mediatek/thermal/mtk_cooler_shutdown.c

// 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/printk.h>
#include <linux/types.h>
#include <linux/kobject.h>
#include "mt-plat/mtk_thermal_monitor.h"

#define MAX_NUM_INSTANCE_MTK_COOLER_SHUTDOWN  3

/* #define MTK_COOLER_SHUTDOWN_UEVENT */
#define MTK_COOLER_SHUTDOWN_SIGNAL

#if defined(MTK_COOLER_SHUTDOWN_SIGNAL)
#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>
#include <linux/sched/task.h>   /* put_task_struct */

#define MAX_LEN	256
#endif

#if 1
#define mtk_cooler_shutdown_dprintk(fmt, args...)	\
	pr_notice("thermal/cooler/shutdown " fmt, ##args)
#else
#define mtk_cooler_shutdown_dprintk(fmt, args...)
#endif

struct sd_state {
	unsigned long state;
	int sd_cnt;
};

static struct thermal_cooling_device
*cl_shutdown_dev[MAX_NUM_INSTANCE_MTK_COOLER_SHUTDOWN] = { 0 };

/* static unsigned long cl_shutdown_state[MAX_NUM_INSTANCE_MTK_COOLER_SHUTDOWN]
 * = { 0 };
 */

static struct sd_state cl_sd_state[MAX_NUM_INSTANCE_MTK_COOLER_SHUTDOWN];

#if defined(MTK_COOLER_SHUTDOWN_SIGNAL)

static unsigned int tm_pid;
static unsigned int tm_input_pid;
static unsigned int mtk_cl_sd_rst;
static struct task_struct *pg_task;

static int sd_debouncet = 1;
/* static int sd_cnt = 0; */
static int sd_happened;
static kuid_t uid = KUIDT_INIT(0);
static kgid_t gid = KGIDT_INIT(1000);

	static ssize_t _mtk_cl_sd_rst_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, &mtk_cl_sd_rst);
	if (ret)
		WARN_ON_ONCE(1);


	if (mtk_cl_sd_rst == 1) {
		int i;

		for (i = MAX_NUM_INSTANCE_MTK_COOLER_SHUTDOWN; i-- > 0;) {
			cl_sd_state[i].state = 0;
			cl_sd_state[i].sd_cnt = 0;
		}
		mtk_cl_sd_rst = 0;
		sd_happened = 0;
		/* sd_cnt = 0; */
	}
	mtk_cooler_shutdown_dprintk("%s %s = %d\n", __func__, tmp,
			mtk_cl_sd_rst);

	return len;
}

int _mtk_cl_sd_rst_read(struct seq_file *m, void *v)
{
	return 0;
}

static int _mtk_cl_sd_rst_open(struct inode *inode, struct file *file)
{
	return single_open(file, _mtk_cl_sd_rst_read, PDE_DATA(inode));
}

static const struct file_operations _cl_sd_rst_fops = {
	.owner = THIS_MODULE,
	.open = _mtk_cl_sd_rst_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.write = _mtk_cl_sd_rst_write,
	.release = single_release,
};

	static ssize_t _mtk_cl_sd_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_cooler_shutdown_dprintk("%s %s = %d\n", __func__, tmp,
			tm_input_pid);

	return len;
}

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

	return 0;
}

static int _mtk_cl_sd_pid_open(struct inode *inode, struct file *file)
{
	return single_open(file, _mtk_cl_sd_pid_read, PDE_DATA(inode));
}

static const struct file_operations _cl_sd_pid_fops = {
	.owner = THIS_MODULE,
	.open = _mtk_cl_sd_pid_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.write = _mtk_cl_sd_pid_write,
	.release = single_release,
};

	static ssize_t _mtk_cl_sd_debouncet_write
(struct file *filp, const char __user *buf, size_t len, loff_t *data)
{
	char desc[MAX_LEN] = { 0 };
	int tmp_dbt = -1;

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

	if (kstrtoint(desc, 10, &tmp_dbt) == 0) {
		if (tmp_dbt >= 0 && tmp_dbt <= 5)
			sd_debouncet = tmp_dbt;
		else
			mtk_cooler_shutdown_dprintk(
					"[%s] oo range %s = %d\n", __func__,
					desc, sd_debouncet);
	} else {
		mtk_cooler_shutdown_dprintk("[%s] bad arg %s = %d\n",
				__func__, desc, sd_debouncet);
	}

	mtk_cooler_shutdown_dprintk("[%s] %s = %d\n", __func__, desc,
			sd_debouncet);

	return len;
}

static int _mtk_cl_sd_debouncet_read(struct seq_file *m, void *v)
{
	seq_printf(m, "%d\n", sd_debouncet);
	mtk_cooler_shutdown_dprintk("[%s] %d\n", __func__, sd_debouncet);

	return 0;
}

static int _mtk_cl_sd_debouncet_open(struct inode *inode, struct file *file)
{
	return single_open(file, _mtk_cl_sd_debouncet_read, PDE_DATA(inode));
}

static const struct file_operations _cl_sd_debouncet_fops = {
	.owner = THIS_MODULE,
	.open = _mtk_cl_sd_debouncet_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.write = _mtk_cl_sd_debouncet_write,
	.release = single_release,
};

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

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

	mtk_cooler_shutdown_dprintk("%s pid is %d, %d\n", __func__,
			tm_pid, tm_input_pid);

	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 = 0;
		info.si_code = 1;
		info.si_addr = NULL;
		ret = do_send_sig_info(SIGIO, &info, pg_task, false);   //JOSH
	}

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

	return ret;
}

#endif

	static int mtk_cl_shutdown_get_max_state
(struct thermal_cooling_device *cdev, unsigned long *state)
{
	*state = 1;
	/* mtk_cooler_shutdown_dprintk(
	 * "mtk_cl_shutdown_get_max_state() %s %d\n",
	 * cdev->type, *state);
	 */

	return 0;
}

	static int mtk_cl_shutdown_get_cur_state
(struct thermal_cooling_device *cdev, unsigned long *state)
{
	/* *state = *((unsigned long *)cdev->devdata); */
	struct sd_state *cl_state = (struct sd_state *) cdev->devdata;

	if (state)
		*state = cl_state->state;
	/* mtk_cooler_shutdown_dprintk(
	 * "mtk_cl_shutdown_get_cur_state() %s %d\n",
	 * cdev->type, *state);
	 */
	return 0;
}

	static int mtk_cl_shutdown_set_cur_state
(struct thermal_cooling_device *cdev, unsigned long state)
{
	struct sd_state *cl_state = (struct sd_state *) cdev->devdata;
#if defined(MTK_COOLER_SHUTDOWN_SIGNAL)
	unsigned long original_state;
#endif
	/* mtk_cooler_shutdown_dprintk(
	 * "mtk_cl_shutdown_set_cur_state() %s %d\n",
	 * cdev->type, state);
	 */
	if (!cl_state)
		return -1;

#if defined(MTK_COOLER_SHUTDOWN_SIGNAL)
	original_state = cl_state->state;
#endif

	cl_state->state = state;

	if (state == 0) {
		if (cl_state->sd_cnt > 0)
			cl_state->sd_cnt--;
	} else if (state == 1) {
		cl_state->sd_cnt++;
	}

	if (sd_debouncet == cl_state->sd_cnt) {
#if defined(MTK_COOLER_SHUTDOWN_UEVENT)
		{
			/* send uevent to notify current call must be dropped */
			char event[11] = "SHUTDOWN=1";
			char *envp[2] = { event, NULL };

			kobject_uevent_env(&(cdev->device.kobj),
					KOBJ_CHANGE, envp);
		}
#endif

#if defined(MTK_COOLER_SHUTDOWN_SIGNAL)
		/* make this an edge trigger instead of level trigger */
		if (sd_happened == 0) {
			/* send signal to target process */
			_mtk_cl_sd_send_signal();
			sd_happened = 1;
		}
#endif
	}

	return 0;
}

/* bind fan callbacks to fan device */
static struct thermal_cooling_device_ops mtk_cl_shutdown_ops = {
	.get_max_state = mtk_cl_shutdown_get_max_state,
	.get_cur_state = mtk_cl_shutdown_get_cur_state,
	.set_cur_state = mtk_cl_shutdown_set_cur_state,
};

static int mtk_cooler_shutdown_register_ltf(void)
{
	int i;

	mtk_cooler_shutdown_dprintk("register ltf\n");

	for (i = MAX_NUM_INSTANCE_MTK_COOLER_SHUTDOWN; i-- > 0;) {
		char temp[20] = { 0 };

		sprintf(temp, "mtk-cl-shutdown%02d", i);
		cl_shutdown_dev[i] = mtk_thermal_cooling_device_register(
				temp, (void *)&cl_sd_state[i],
				&mtk_cl_shutdown_ops);
	}

	return 0;
}

static void mtk_cooler_shutdown_unregister_ltf(void)
{
	int i;

	mtk_cooler_shutdown_dprintk("unregister ltf\n");

	for (i = MAX_NUM_INSTANCE_MTK_COOLER_SHUTDOWN; i-- > 0;) {
		if (cl_shutdown_dev[i]) {
			mtk_thermal_cooling_device_unregister(
					cl_shutdown_dev[i]);
			cl_shutdown_dev[i] = NULL;
			cl_sd_state[i].state = 0;
			cl_sd_state[i].sd_cnt = 0;
		}
	}
}


static int __init mtk_cooler_shutdown_init(void)
{
	int err = 0;
	int i;

	for (i = MAX_NUM_INSTANCE_MTK_COOLER_SHUTDOWN; i-- > 0;) {
		cl_shutdown_dev[i] = NULL;
		cl_sd_state[i].state = 0;
		cl_sd_state[i].sd_cnt = 0;
	}

	mtk_cooler_shutdown_dprintk("init\n");

#if defined(MTK_COOLER_SHUTDOWN_SIGNAL)
	{
		struct proc_dir_entry *entry = NULL;
		struct proc_dir_entry *dir_entry
			= mtk_thermal_get_proc_drv_therm_dir_entry();

		if (!dir_entry) {
			mtk_cooler_shutdown_dprintk(
				"%s mkdir /proc/driver/thermal failed\n",
						    __func__);
			return 0;
		}

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

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

		entry =
			proc_create("clsd_dbt", 0664,
					dir_entry,
				&_cl_sd_debouncet_fops);
		if (!entry)
			mtk_cooler_shutdown_dprintk(
				"%s clsd_dbt creation failed\n", __func__);
		else
			proc_set_user(entry, uid, gid);
	}
#endif

	err = mtk_cooler_shutdown_register_ltf();
	if (err)
		goto err_unreg;

	return 0;

err_unreg:
	mtk_cooler_shutdown_unregister_ltf();
	return err;
}

static void __exit mtk_cooler_shutdown_exit(void)
{
	mtk_cooler_shutdown_dprintk("exit\n");
	mtk_cooler_shutdown_unregister_ltf();
}
module_init(mtk_cooler_shutdown_init);
module_exit(mtk_cooler_shutdown_exit);