13c910ecbSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only
222b1c841SBeniamino Galvani /*
322b1c841SBeniamino Galvani * Watchdog driver for Ricoh RN5T618 PMIC
422b1c841SBeniamino Galvani *
522b1c841SBeniamino Galvani * Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com>
622b1c841SBeniamino Galvani */
722b1c841SBeniamino Galvani
822b1c841SBeniamino Galvani #include <linux/device.h>
922b1c841SBeniamino Galvani #include <linux/mfd/rn5t618.h>
1022b1c841SBeniamino Galvani #include <linux/module.h>
1122b1c841SBeniamino Galvani #include <linux/platform_device.h>
1222b1c841SBeniamino Galvani #include <linux/watchdog.h>
1322b1c841SBeniamino Galvani
1422b1c841SBeniamino Galvani #define DRIVER_NAME "rn5t618-wdt"
1522b1c841SBeniamino Galvani
1622b1c841SBeniamino Galvani static bool nowayout = WATCHDOG_NOWAYOUT;
1722b1c841SBeniamino Galvani static unsigned int timeout;
1822b1c841SBeniamino Galvani
1922b1c841SBeniamino Galvani module_param(timeout, uint, 0);
2022b1c841SBeniamino Galvani MODULE_PARM_DESC(timeout, "Initial watchdog timeout in seconds");
2122b1c841SBeniamino Galvani
2222b1c841SBeniamino Galvani module_param(nowayout, bool, 0);
2322b1c841SBeniamino Galvani MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
2422b1c841SBeniamino Galvani __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
2522b1c841SBeniamino Galvani
2622b1c841SBeniamino Galvani struct rn5t618_wdt {
2722b1c841SBeniamino Galvani struct watchdog_device wdt_dev;
2822b1c841SBeniamino Galvani struct rn5t618 *rn5t618;
2922b1c841SBeniamino Galvani };
3022b1c841SBeniamino Galvani
3122b1c841SBeniamino Galvani /*
3222b1c841SBeniamino Galvani * This array encodes the values of WDOGTIM field for the supported
3322b1c841SBeniamino Galvani * watchdog expiration times. If the watchdog is not accessed before
3422b1c841SBeniamino Galvani * the timer expiration, the PMU generates an interrupt and if the CPU
3522b1c841SBeniamino Galvani * doesn't clear it within one second the system is restarted.
3622b1c841SBeniamino Galvani */
3722b1c841SBeniamino Galvani static const struct {
3822b1c841SBeniamino Galvani u8 reg_val;
3922b1c841SBeniamino Galvani unsigned int time;
4022b1c841SBeniamino Galvani } rn5t618_wdt_map[] = {
4122b1c841SBeniamino Galvani { 0, 1 },
4222b1c841SBeniamino Galvani { 1, 8 },
4322b1c841SBeniamino Galvani { 2, 32 },
4422b1c841SBeniamino Galvani { 3, 128 },
4522b1c841SBeniamino Galvani };
4622b1c841SBeniamino Galvani
rn5t618_wdt_set_timeout(struct watchdog_device * wdt_dev,unsigned int t)4722b1c841SBeniamino Galvani static int rn5t618_wdt_set_timeout(struct watchdog_device *wdt_dev,
4822b1c841SBeniamino Galvani unsigned int t)
4922b1c841SBeniamino Galvani {
5022b1c841SBeniamino Galvani struct rn5t618_wdt *wdt = watchdog_get_drvdata(wdt_dev);
5122b1c841SBeniamino Galvani int ret, i;
5222b1c841SBeniamino Galvani
5322b1c841SBeniamino Galvani for (i = 0; i < ARRAY_SIZE(rn5t618_wdt_map); i++) {
5422b1c841SBeniamino Galvani if (rn5t618_wdt_map[i].time + 1 >= t)
5522b1c841SBeniamino Galvani break;
5622b1c841SBeniamino Galvani }
5722b1c841SBeniamino Galvani
5822b1c841SBeniamino Galvani if (i == ARRAY_SIZE(rn5t618_wdt_map))
5922b1c841SBeniamino Galvani return -EINVAL;
6022b1c841SBeniamino Galvani
6122b1c841SBeniamino Galvani ret = regmap_update_bits(wdt->rn5t618->regmap, RN5T618_WATCHDOG,
6222b1c841SBeniamino Galvani RN5T618_WATCHDOG_WDOGTIM_M,
6322b1c841SBeniamino Galvani rn5t618_wdt_map[i].reg_val);
6422b1c841SBeniamino Galvani if (!ret)
6522b1c841SBeniamino Galvani wdt_dev->timeout = rn5t618_wdt_map[i].time;
6622b1c841SBeniamino Galvani
6722b1c841SBeniamino Galvani return ret;
6822b1c841SBeniamino Galvani }
6922b1c841SBeniamino Galvani
rn5t618_wdt_start(struct watchdog_device * wdt_dev)7022b1c841SBeniamino Galvani static int rn5t618_wdt_start(struct watchdog_device *wdt_dev)
7122b1c841SBeniamino Galvani {
7222b1c841SBeniamino Galvani struct rn5t618_wdt *wdt = watchdog_get_drvdata(wdt_dev);
7322b1c841SBeniamino Galvani int ret;
7422b1c841SBeniamino Galvani
7522b1c841SBeniamino Galvani ret = rn5t618_wdt_set_timeout(wdt_dev, wdt_dev->timeout);
7622b1c841SBeniamino Galvani if (ret)
7722b1c841SBeniamino Galvani return ret;
7822b1c841SBeniamino Galvani
7922b1c841SBeniamino Galvani /* enable repower-on */
8022b1c841SBeniamino Galvani ret = regmap_update_bits(wdt->rn5t618->regmap, RN5T618_REPCNT,
8122b1c841SBeniamino Galvani RN5T618_REPCNT_REPWRON,
8222b1c841SBeniamino Galvani RN5T618_REPCNT_REPWRON);
8322b1c841SBeniamino Galvani if (ret)
8422b1c841SBeniamino Galvani return ret;
8522b1c841SBeniamino Galvani
8622b1c841SBeniamino Galvani /* enable watchdog */
8722b1c841SBeniamino Galvani ret = regmap_update_bits(wdt->rn5t618->regmap, RN5T618_WATCHDOG,
8822b1c841SBeniamino Galvani RN5T618_WATCHDOG_WDOGEN,
8922b1c841SBeniamino Galvani RN5T618_WATCHDOG_WDOGEN);
9022b1c841SBeniamino Galvani if (ret)
9122b1c841SBeniamino Galvani return ret;
9222b1c841SBeniamino Galvani
9322b1c841SBeniamino Galvani /* enable watchdog interrupt */
9422b1c841SBeniamino Galvani return regmap_update_bits(wdt->rn5t618->regmap, RN5T618_PWRIREN,
9522b1c841SBeniamino Galvani RN5T618_PWRIRQ_IR_WDOG,
9622b1c841SBeniamino Galvani RN5T618_PWRIRQ_IR_WDOG);
9722b1c841SBeniamino Galvani }
9822b1c841SBeniamino Galvani
rn5t618_wdt_stop(struct watchdog_device * wdt_dev)9922b1c841SBeniamino Galvani static int rn5t618_wdt_stop(struct watchdog_device *wdt_dev)
10022b1c841SBeniamino Galvani {
10122b1c841SBeniamino Galvani struct rn5t618_wdt *wdt = watchdog_get_drvdata(wdt_dev);
10222b1c841SBeniamino Galvani
10322b1c841SBeniamino Galvani return regmap_update_bits(wdt->rn5t618->regmap, RN5T618_WATCHDOG,
10422b1c841SBeniamino Galvani RN5T618_WATCHDOG_WDOGEN, 0);
10522b1c841SBeniamino Galvani }
10622b1c841SBeniamino Galvani
rn5t618_wdt_ping(struct watchdog_device * wdt_dev)10722b1c841SBeniamino Galvani static int rn5t618_wdt_ping(struct watchdog_device *wdt_dev)
10822b1c841SBeniamino Galvani {
10922b1c841SBeniamino Galvani struct rn5t618_wdt *wdt = watchdog_get_drvdata(wdt_dev);
11022b1c841SBeniamino Galvani unsigned int val;
11122b1c841SBeniamino Galvani int ret;
11222b1c841SBeniamino Galvani
11322b1c841SBeniamino Galvani /* The counter is restarted after a R/W access to watchdog register */
11422b1c841SBeniamino Galvani ret = regmap_read(wdt->rn5t618->regmap, RN5T618_WATCHDOG, &val);
11522b1c841SBeniamino Galvani if (ret)
11622b1c841SBeniamino Galvani return ret;
11722b1c841SBeniamino Galvani
11822b1c841SBeniamino Galvani ret = regmap_write(wdt->rn5t618->regmap, RN5T618_WATCHDOG, val);
11922b1c841SBeniamino Galvani if (ret)
12022b1c841SBeniamino Galvani return ret;
12122b1c841SBeniamino Galvani
12222b1c841SBeniamino Galvani /* Clear pending watchdog interrupt */
12322b1c841SBeniamino Galvani return regmap_update_bits(wdt->rn5t618->regmap, RN5T618_PWRIRQ,
12422b1c841SBeniamino Galvani RN5T618_PWRIRQ_IR_WDOG, 0);
12522b1c841SBeniamino Galvani }
12622b1c841SBeniamino Galvani
1276c368932SBhumika Goyal static const struct watchdog_info rn5t618_wdt_info = {
12822b1c841SBeniamino Galvani .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE |
12922b1c841SBeniamino Galvani WDIOF_KEEPALIVEPING,
13022b1c841SBeniamino Galvani .identity = DRIVER_NAME,
13122b1c841SBeniamino Galvani };
13222b1c841SBeniamino Galvani
13385f15cfcSJulia Lawall static const struct watchdog_ops rn5t618_wdt_ops = {
13422b1c841SBeniamino Galvani .owner = THIS_MODULE,
13522b1c841SBeniamino Galvani .start = rn5t618_wdt_start,
13622b1c841SBeniamino Galvani .stop = rn5t618_wdt_stop,
13722b1c841SBeniamino Galvani .ping = rn5t618_wdt_ping,
13822b1c841SBeniamino Galvani .set_timeout = rn5t618_wdt_set_timeout,
13922b1c841SBeniamino Galvani };
14022b1c841SBeniamino Galvani
rn5t618_wdt_probe(struct platform_device * pdev)14122b1c841SBeniamino Galvani static int rn5t618_wdt_probe(struct platform_device *pdev)
14222b1c841SBeniamino Galvani {
143cc718597SGuenter Roeck struct device *dev = &pdev->dev;
144cc718597SGuenter Roeck struct rn5t618 *rn5t618 = dev_get_drvdata(dev->parent);
14522b1c841SBeniamino Galvani struct rn5t618_wdt *wdt;
14622b1c841SBeniamino Galvani int min_timeout, max_timeout;
14747c00805SMarcus Folkesson int ret;
14847c00805SMarcus Folkesson unsigned int val;
14922b1c841SBeniamino Galvani
150cc718597SGuenter Roeck wdt = devm_kzalloc(dev, sizeof(struct rn5t618_wdt), GFP_KERNEL);
15122b1c841SBeniamino Galvani if (!wdt)
15222b1c841SBeniamino Galvani return -ENOMEM;
15322b1c841SBeniamino Galvani
15422b1c841SBeniamino Galvani min_timeout = rn5t618_wdt_map[0].time;
15522b1c841SBeniamino Galvani max_timeout = rn5t618_wdt_map[ARRAY_SIZE(rn5t618_wdt_map) - 1].time;
15622b1c841SBeniamino Galvani
15722b1c841SBeniamino Galvani wdt->rn5t618 = rn5t618;
15822b1c841SBeniamino Galvani wdt->wdt_dev.info = &rn5t618_wdt_info;
15922b1c841SBeniamino Galvani wdt->wdt_dev.ops = &rn5t618_wdt_ops;
16022b1c841SBeniamino Galvani wdt->wdt_dev.min_timeout = min_timeout;
16122b1c841SBeniamino Galvani wdt->wdt_dev.max_timeout = max_timeout;
16222b1c841SBeniamino Galvani wdt->wdt_dev.timeout = max_timeout;
163cc718597SGuenter Roeck wdt->wdt_dev.parent = dev;
16422b1c841SBeniamino Galvani
16547c00805SMarcus Folkesson /* Read out previous power-off factor */
16647c00805SMarcus Folkesson ret = regmap_read(wdt->rn5t618->regmap, RN5T618_POFFHIS, &val);
16747c00805SMarcus Folkesson if (ret)
16847c00805SMarcus Folkesson return ret;
16947c00805SMarcus Folkesson
17047c00805SMarcus Folkesson if (val & RN5T618_POFFHIS_VINDET)
17147c00805SMarcus Folkesson wdt->wdt_dev.bootstatus = WDIOF_POWERUNDER;
17247c00805SMarcus Folkesson else if (val & RN5T618_POFFHIS_WDG)
17347c00805SMarcus Folkesson wdt->wdt_dev.bootstatus = WDIOF_CARDRESET;
17447c00805SMarcus Folkesson
17522b1c841SBeniamino Galvani watchdog_set_drvdata(&wdt->wdt_dev, wdt);
176cc718597SGuenter Roeck watchdog_init_timeout(&wdt->wdt_dev, timeout, dev);
17722b1c841SBeniamino Galvani watchdog_set_nowayout(&wdt->wdt_dev, nowayout);
17822b1c841SBeniamino Galvani
17922b1c841SBeniamino Galvani platform_set_drvdata(pdev, wdt);
18022b1c841SBeniamino Galvani
181*4095b94dSUwe Kleine-König return devm_watchdog_register_device(dev, &wdt->wdt_dev);
18222b1c841SBeniamino Galvani }
18322b1c841SBeniamino Galvani
18422b1c841SBeniamino Galvani static struct platform_driver rn5t618_wdt_driver = {
18522b1c841SBeniamino Galvani .probe = rn5t618_wdt_probe,
18622b1c841SBeniamino Galvani .driver = {
18722b1c841SBeniamino Galvani .name = DRIVER_NAME,
18822b1c841SBeniamino Galvani },
18922b1c841SBeniamino Galvani };
19022b1c841SBeniamino Galvani
19122b1c841SBeniamino Galvani module_platform_driver(rn5t618_wdt_driver);
19222b1c841SBeniamino Galvani
193a76dfb85SAndreas Kemnade MODULE_ALIAS("platform:rn5t618-wdt");
19422b1c841SBeniamino Galvani MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>");
19522b1c841SBeniamino Galvani MODULE_DESCRIPTION("RN5T618 watchdog driver");
19622b1c841SBeniamino Galvani MODULE_LICENSE("GPL v2");
197