projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| de6303ab WS |
1 | /* |
| 2 | * Watchdog driver for the RTC based watchdog in STMP3xxx and i.MX23/28 | |
| 3 | * | |
| 4 | * Author: Wolfram Sang <w.sang@pengutronix.de> | |
| 5 | * | |
| 6 | * Copyright (C) 2011-12 Wolfram Sang, Pengutronix | |
| 7 | * | |
| 8 | * This program is free software; you can redistribute it and/or modify it | |
| 9 | * under the terms of the GNU General Public License version 2 as published by | |
| 10 | * the Free Software Foundation. | |
| 11 | */ | |
| 12 | #include <linux/init.h> | |
| 13 | #include <linux/kernel.h> | |
| 14 | #include <linux/module.h> | |
| de6303ab WS |
15 | #include <linux/watchdog.h> |
| 16 | #include <linux/platform_device.h> | |
| 17 | #include <linux/stmp3xxx_rtc_wdt.h> | |
| 18 | ||
| 19 | #define WDOG_TICK_RATE 1000 /* 1 kHz clock */ | |
| 20 | #define STMP3XXX_DEFAULT_TIMEOUT 19 | |
| 21 | #define STMP3XXX_MAX_TIMEOUT (UINT_MAX / WDOG_TICK_RATE) | |
| 22 | ||
| 23 | static int heartbeat = STMP3XXX_DEFAULT_TIMEOUT; | |
| 24 | module_param(heartbeat, uint, 0); | |
| 25 | MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat period in seconds from 1 to " | |
| 26 | __MODULE_STRING(STMP3XXX_MAX_TIMEOUT) ", default " | |
| 27 | __MODULE_STRING(STMP3XXX_DEFAULT_TIMEOUT)); | |
| 28 | ||
| 29 | static int wdt_start(struct watchdog_device *wdd) | |
| 30 | { | |
| 31 | struct device *dev = watchdog_get_drvdata(wdd); | |
| bc8fdfbe | 32 | struct stmp3xxx_wdt_pdata *pdata = dev_get_platdata(dev); |
| de6303ab WS |
33 | |
| 34 | pdata->wdt_set_timeout(dev->parent, wdd->timeout * WDOG_TICK_RATE); | |
| 35 | return 0; | |
| 36 | } | |
| 37 | ||
| 38 | static int wdt_stop(struct watchdog_device *wdd) | |
| 39 | { | |
| 40 | struct device *dev = watchdog_get_drvdata(wdd); | |
| bc8fdfbe | 41 | struct stmp3xxx_wdt_pdata *pdata = dev_get_platdata(dev); |
| de6303ab WS |
42 | |
| 43 | pdata->wdt_set_timeout(dev->parent, 0); | |
| 44 | return 0; | |
| 45 | } | |
| 46 | ||
| 47 | static int wdt_set_timeout(struct watchdog_device *wdd, unsigned new_timeout) | |
| 48 | { | |
| 49 | wdd->timeout = new_timeout; | |
| 50 | return wdt_start(wdd); | |
| 51 | } | |
| 52 | ||
| 53 | static const struct watchdog_info stmp3xxx_wdt_ident = { | |
| 54 | .options = WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, | |
| 55 | .identity = "STMP3XXX RTC Watchdog", | |
| 56 | }; | |
| 57 | ||
| 58 | static const struct watchdog_ops stmp3xxx_wdt_ops = { | |
| 59 | .owner = THIS_MODULE, | |
| 60 | .start = wdt_start, | |
| 61 | .stop = wdt_stop, | |
| 62 | .set_timeout = wdt_set_timeout, | |
| 63 | }; | |
| 64 | ||
| 65 | static struct watchdog_device stmp3xxx_wdd = { | |
| 66 | .info = &stmp3xxx_wdt_ident, | |
| 67 | .ops = &stmp3xxx_wdt_ops, | |
| 68 | .min_timeout = 1, | |
| 69 | .max_timeout = STMP3XXX_MAX_TIMEOUT, | |
| 70 | .status = WATCHDOG_NOWAYOUT_INIT_STATUS, | |
| 71 | }; | |
| 72 | ||
| 73 | static int stmp3xxx_wdt_probe(struct platform_device *pdev) | |
| 74 | { | |
| 75 | int ret; | |
| 76 | ||
| 77 | watchdog_set_drvdata(&stmp3xxx_wdd, &pdev->dev); | |
| 78 | ||
| 79 | stmp3xxx_wdd.timeout = clamp_t(unsigned, heartbeat, 1, STMP3XXX_MAX_TIMEOUT); | |
| 80 | ||
| 81 | ret = watchdog_register_device(&stmp3xxx_wdd); | |
| 82 | if (ret < 0) { | |
| 83 | dev_err(&pdev->dev, "cannot register watchdog device\n"); | |
| 84 | return ret; | |
| 85 | } | |
| 86 | ||
| 87 | dev_info(&pdev->dev, "initialized watchdog with heartbeat %ds\n", | |
| 88 | stmp3xxx_wdd.timeout); | |
| 89 | return 0; | |
| 90 | } | |
| 91 | ||
| 92 | static int stmp3xxx_wdt_remove(struct platform_device *pdev) | |
| 93 | { | |
| 94 | watchdog_unregister_device(&stmp3xxx_wdd); | |
| 95 | return 0; | |
| 96 | } | |
| 97 | ||
| 98 | static struct platform_driver stmp3xxx_wdt_driver = { | |
| 99 | .driver = { | |
| 100 | .name = "stmp3xxx_rtc_wdt", | |
| 101 | }, | |
| 102 | .probe = stmp3xxx_wdt_probe, | |
| 103 | .remove = stmp3xxx_wdt_remove, | |
| 104 | }; | |
| 105 | module_platform_driver(stmp3xxx_wdt_driver); | |
| 106 | ||
| 107 | MODULE_DESCRIPTION("STMP3XXX RTC Watchdog Driver"); | |
| 108 | MODULE_LICENSE("GPL v2"); | |
| 109 | MODULE_AUTHOR("Wolfram Sang <w.sang@pengutronix.de>"); |