/* * Watchdog driver for Cirrus Logic EP93xx family of devices. * * Copyright (c) 2004 Ray Lehtiniemi * Copyright (c) 2006 Tower Technologies * Based on ep93xx driver, bits from alim7101_wdt.c * * Authors: Ray Lehtiniemi , * Alessandro Zummo * * Copyright (c) 2012 H Hartley Sweeten * Convert to a platform device and use the watchdog framework API * * This file is licensed under the terms of the GNU General Public * License version 2. This program is licensed "as is" without any * warranty of any kind, whether express or implied. * * This watchdog fires after 250msec, which is a too short interval * for us to rely on the user space daemon alone. So we ping the * wdt each ~200msec and eventually stop doing it if the user space * daemon dies. * * TODO: * * - Test last reset from watchdog status * - Add a few missing ioctls */ #include #include #include #include #include #define WDT_VERSION "0.4" /* default timeout (secs) */ #define WDT_TIMEOUT 30 static bool nowayout = WATCHDOG_NOWAYOUT; module_param(nowayout, bool, 0); MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started"); static unsigned int timeout = WDT_TIMEOUT; module_param(timeout, uint, 0); MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. (1<=timeout<=3600, default=" __MODULE_STRING(WDT_TIMEOUT) ")"); static void __iomem *mmio_base; static struct timer_list timer; static unsigned long next_heartbeat; #define EP93XX_WATCHDOG 0x00 #define EP93XX_WDSTATUS 0x04 /* reset the wdt every ~200ms - the heartbeat of the device is 0.250 seconds*/ #define WDT_INTERVAL (HZ/5) static void ep93xx_wdt_timer_ping(unsigned long data) { if (time_before(jiffies, next_heartbeat)) writel(0x5555, mmio_base + EP93XX_WATCHDOG); /* Re-set the timer interval */ mod_timer(&timer, jiffies + WDT_INTERVAL); } static int ep93xx_wdt_start(struct watchdog_device *wdd) { next_heartbeat = jiffies + (timeout * HZ); writel(0xaaaa, mmio_base + EP93XX_WATCHDOG); mod_timer(&timer, jiffies + WDT_INTERVAL); return 0; } static int ep93xx_wdt_stop(struct watchdog_device *wdd) { del_timer_sync(&timer); writel(0xaa55, mmio_base + EP93XX_WATCHDOG); return 0; } static int ep93xx_wdt_keepalive(struct watchdog_device *wdd) { /* user land ping */ next_heartbeat = jiffies + (timeout * HZ); return 0; } static const struct watchdog_info ep93xx_wdt_ident = { .options = WDIOF_CARDRESET | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING, .identity = "EP93xx Watchdog", }; static struct watchdog_ops ep93xx_wdt_ops = { .owner = THIS_MODULE, .start = ep93xx_wdt_start, .stop = ep93xx_wdt_stop, .ping = ep93xx_wdt_keepalive, }; static struct watchdog_device ep93xx_wdt_wdd = { .info = &ep93xx_wdt_ident, .ops = &ep93xx_wdt_ops, }; static int ep93xx_wdt_probe(struct platform_device *pdev) { struct resource *res; unsigned long val; int err; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); mmio_base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(mmio_base)) return PTR_ERR(mmio_base); if (timeout < 1 || timeout > 3600) { timeout = WDT_TIMEOUT; dev_warn(&pdev->dev, "timeout value must be 1<=x<=3600, using %d\n", timeout); } val = readl(mmio_base + EP93XX_WATCHDOG); ep93xx_wdt_wdd.bootstatus = (val & 0x01) ? WDIOF_CARDRESET : 0; ep93xx_wdt_wdd.timeout = timeout; ep93xx_wdt_wdd.parent = &pdev->dev; watchdog_set_nowayout(&ep93xx_wdt_wdd, nowayout); setup_timer(&timer, ep93xx_wdt_timer_ping, 1); err = watchdog_register_device(&ep93xx_wdt_wdd); if (err) return err; dev_info(&pdev->dev, "EP93XX watchdog, driver version " WDT_VERSION "%s\n", (val & 0x08) ? " (nCS1 disable detected)" : ""); return 0; } static int ep93xx_wdt_remove(struct platform_device *pdev) { watchdog_unregister_device(&ep93xx_wdt_wdd); return 0; } static struct platform_driver ep93xx_wdt_driver = { .driver = { .name = "ep93xx-wdt", }, .probe = ep93xx_wdt_probe, .remove = ep93xx_wdt_remove, }; module_platform_driver(ep93xx_wdt_driver); MODULE_AUTHOR("Ray Lehtiniemi "); MODULE_AUTHOR("Alessandro Zummo "); MODULE_AUTHOR("H Hartley Sweeten "); MODULE_DESCRIPTION("EP93xx Watchdog"); MODULE_LICENSE("GPL"); MODULE_VERSION(WDT_VERSION); treef63906f41699c8e38af9d12b063e2ceab0286ef2 /Documentation/crc32.txt parente34bac726d27056081d0250c0e173e4b155aa340 (diff)parent868c97a846a73e937d835b09b8c885a69df50ec8 (diff)
Merge tag 'docs-4.10' of git://git.lwn.net/linuxHEADmaster
Pull documentation update from Jonathan Corbet: "These are the documentation changes for 4.10. It's another busy cycle for the docs tree, as the sphinx conversion continues. Highlights include: - Further work on PDF output, which remains a bit of a pain but should be more solid now. - Five more DocBook template files converted to Sphinx. Only 27 to go... Lots of plain-text files have also been converted and integrated. - Images in binary formats have been replaced with more source-friendly versions. - Various bits of organizational work, including the renaming of various files discussed at the kernel summit. - New documentation for the device_link mechanism. ... and, of course, lots of typo fixes and small updates" * tag 'docs-4.10' of git://git.lwn.net/linux: (193 commits) dma-buf: Extract dma-buf.rst Update Documentation/00-INDEX docs: 00-INDEX: document directories/files with no docs docs: 00-INDEX: remove non-existing entries docs: 00-INDEX: add missing entries for documentation files/dirs docs: 00-INDEX: consolidate process/ and admin-guide/ description scripts: add a script to check if Documentation/00-INDEX is sane Docs: change sh -> awk in REPORTING-BUGS Documentation/core-api/device_link: Add initial documentation core-api: remove an unexpected unident ppc/idle: Add documentation for powersave=off Doc: Correct typo, "Introdution" => "Introduction" Documentation/atomic_ops.txt: convert to ReST markup Documentation/local_ops.txt: convert to ReST markup Documentation/assoc_array.txt: convert to ReST markup docs-rst: parse-headers.pl: cleanup the documentation docs-rst: fix media cleandocs target docs-rst: media/Makefile: reorganize the rules docs-rst: media: build SVG from graphviz files docs-rst: replace bayer.png by a SVG image ...
Diffstat (limited to 'Documentation/crc32.txt')