148 lines · c
1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (C) ST-Ericsson SA 2011-20134 *5 * Author: Mathieu Poirier <mathieu.poirier@linaro.org> for ST-Ericsson6 * Author: Jonas Aaberg <jonas.aberg@stericsson.com> for ST-Ericsson7 */8 9#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt10 11#include <linux/module.h>12#include <linux/kernel.h>13#include <linux/moduleparam.h>14#include <linux/err.h>15#include <linux/uaccess.h>16#include <linux/watchdog.h>17#include <linux/platform_device.h>18 19#include <linux/mfd/dbx500-prcmu.h>20 21#define WATCHDOG_TIMEOUT 600 /* 10 minutes */22 23#define WATCHDOG_MIN 024#define WATCHDOG_MAX28 268435 /* 28 bit resolution in ms == 268435.455 s */25 26static unsigned int timeout = WATCHDOG_TIMEOUT;27module_param(timeout, uint, 0);28MODULE_PARM_DESC(timeout,29 "Watchdog timeout in seconds. default="30 __MODULE_STRING(WATCHDOG_TIMEOUT) ".");31 32static bool nowayout = WATCHDOG_NOWAYOUT;33module_param(nowayout, bool, 0);34MODULE_PARM_DESC(nowayout,35 "Watchdog cannot be stopped once started (default="36 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");37 38static int db8500_wdt_start(struct watchdog_device *wdd)39{40 return prcmu_enable_a9wdog(PRCMU_WDOG_ALL);41}42 43static int db8500_wdt_stop(struct watchdog_device *wdd)44{45 return prcmu_disable_a9wdog(PRCMU_WDOG_ALL);46}47 48static int db8500_wdt_keepalive(struct watchdog_device *wdd)49{50 return prcmu_kick_a9wdog(PRCMU_WDOG_ALL);51}52 53static int db8500_wdt_set_timeout(struct watchdog_device *wdd,54 unsigned int timeout)55{56 db8500_wdt_stop(wdd);57 prcmu_load_a9wdog(PRCMU_WDOG_ALL, timeout * 1000);58 db8500_wdt_start(wdd);59 60 return 0;61}62 63static const struct watchdog_info db8500_wdt_info = {64 .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,65 .identity = "DB8500 WDT",66 .firmware_version = 1,67};68 69static const struct watchdog_ops db8500_wdt_ops = {70 .owner = THIS_MODULE,71 .start = db8500_wdt_start,72 .stop = db8500_wdt_stop,73 .ping = db8500_wdt_keepalive,74 .set_timeout = db8500_wdt_set_timeout,75};76 77static struct watchdog_device db8500_wdt = {78 .info = &db8500_wdt_info,79 .ops = &db8500_wdt_ops,80 .min_timeout = WATCHDOG_MIN,81 .max_timeout = WATCHDOG_MAX28,82};83 84static int db8500_wdt_probe(struct platform_device *pdev)85{86 struct device *dev = &pdev->dev;87 int ret;88 89 timeout = 600; /* Default to 10 minutes */90 db8500_wdt.parent = dev;91 watchdog_set_nowayout(&db8500_wdt, nowayout);92 93 /* disable auto off on sleep */94 prcmu_config_a9wdog(PRCMU_WDOG_CPU1, false);95 96 /* set HW initial value */97 prcmu_load_a9wdog(PRCMU_WDOG_ALL, timeout * 1000);98 99 ret = devm_watchdog_register_device(dev, &db8500_wdt);100 if (ret)101 return ret;102 103 dev_info(dev, "initialized\n");104 105 return 0;106}107 108static int db8500_wdt_suspend(struct platform_device *pdev,109 pm_message_t state)110{111 if (watchdog_active(&db8500_wdt)) {112 db8500_wdt_stop(&db8500_wdt);113 prcmu_config_a9wdog(PRCMU_WDOG_CPU1, true);114 115 prcmu_load_a9wdog(PRCMU_WDOG_ALL, timeout * 1000);116 db8500_wdt_start(&db8500_wdt);117 }118 return 0;119}120 121static int db8500_wdt_resume(struct platform_device *pdev)122{123 if (watchdog_active(&db8500_wdt)) {124 db8500_wdt_stop(&db8500_wdt);125 prcmu_config_a9wdog(PRCMU_WDOG_CPU1, false);126 127 prcmu_load_a9wdog(PRCMU_WDOG_ALL, timeout * 1000);128 db8500_wdt_start(&db8500_wdt);129 }130 return 0;131}132 133static struct platform_driver db8500_wdt_driver = {134 .probe = db8500_wdt_probe,135 .suspend = pm_ptr(db8500_wdt_suspend),136 .resume = pm_ptr(db8500_wdt_resume),137 .driver = {138 .name = "db8500_wdt",139 },140};141 142module_platform_driver(db8500_wdt_driver);143 144MODULE_AUTHOR("Jonas Aaberg <jonas.aberg@stericsson.com>");145MODULE_DESCRIPTION("DB8500 Watchdog Driver");146MODULE_LICENSE("GPL");147MODULE_ALIAS("platform:db8500_wdt");148