#!/usr/bin/env python3
#
# SPDX-FileCopyrightText: Copyright (c) 2020-2022 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
# SPDX-License-Identifier: LicenseRef-NvidiaProprietary
#
# NVIDIA CORPORATION, its affiliates and licensors retain all intellectual
# property and proprietary rights in and to this material, related
# documentation and any modifications thereto. Any use, reproduction,
# disclosure or distribution of this material and related documentation
# without an express license agreement from NVIDIA CORPORATION or
# its affiliates is strictly prohibited.

import time
from pathlib import Path

class SocthermIRQ(object):
    def __init__(self, path):
        self.path = path
        self.irq_cnt_prev = self.irq_cnt()

    def get_new_event(self):
        new = self.irq_cnt() - self.irq_cnt_prev
        self.irq_cnt_prev += new
        return new

    def irq_cnt(self):
        return int(self.path.read_text().strip())

def oc_event_t194():
    soctherm_oc = None
    hwmons = [p for p in Path('/sys/class/hwmon').glob('*')]
    for hwmon in hwmons:
        name = hwmon.joinpath('name').read_text().strip()
        if name == 'soctherm_oc':
            soctherm_oc = hwmon

    if soctherm_oc:
        soctherm_irqs = [SocthermIRQ(p) for p in soctherm_oc.glob('oc*irq_cnt')]
    else:
        return None

    while True:
        for irq in soctherm_irqs:
            if irq.get_new_event() > 0:
                return ('throttle-alert', 'Over-current')
        time.sleep(1)

def oc_event_t234():
    soctherm_oc = None
    hwmons = [p for p in Path('/sys/class/hwmon').glob('*')]
    for hwmon in hwmons:
        oc_hwmon_name = 'soctherm_oc'
        name = hwmon.joinpath('name').read_text().strip()
        if oc_hwmon_name == name:
            soctherm_oc = hwmon

    if soctherm_oc:
        evt_pattern = 'oc*_event_cnt'
        soctherm_irqs = [SocthermIRQ(p) for p in soctherm_oc.glob(evt_pattern)]
    else:
        return None

    while True:
        for irq in soctherm_irqs:
            if irq.get_new_event() > 0:
                return ('throttle-alert', 'Over-current')

        time.sleep(1)

oc_event_func = {}
oc_event_func['tegra194'] = oc_event_t194
oc_event_func['tegra234'] = oc_event_t234

def soc_family():
    try:
        with open("/proc/device-tree/compatible") as f:
            soc_family = None
            compatible = f.read().split('\x00')
            for s in compatible:
                for soc in oc_event_func.keys():
                    if soc in s:
                        soc_family = soc
            return soc_family
    except IOError:
            return 'unknown'

class OcEvent(object):
    def __init__(self):
        if soc_family():
            self.wait_event = oc_event_func[soc_family()]

    def wait_event():
        return self.wait_event()

if __name__ == '__main__':
    print(f"SoC family: {soc_family()}")
    print("Waiting for OC event..")
    oc = OcEvent()

    while True:
        oc.wait_event()
        print("OC event occurred.")