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![Pratyush Anand](/assets/img/avatar_default.png)
/sys/class/watchdog/watchdogn/device/modalias can help to identify the driver/module for a given watchdog node. However, many wdt devices do not set their parent and so, we do not see an entry for device in sysfs for such devices. This patch fixes parent of watchdog_device so that /sys/class/watchdog/watchdogn/device is populated. Exceptions: booke, diag288, octeon, softdog and w83627hf -- They do not have any parent. Not sure, how we can identify driver for these devices. Signed-off-by: Pratyush Anand <panand@redhat.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Acked-by: Guenter Roeck <linux@roeck-us.net> Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com> Acked-by: Lee Jones <lee.jones@linaro.org> Acked-by: Lubomir Rintel <lkundrak@v3.sk> Acked-by: Maxime Coquelin <maxime.coquelin@st.com> Acked-by: Thierry Reding <treding@nvidia.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
178 lines
4.5 KiB
C
178 lines
4.5 KiB
C
/*
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* txx9wdt: A Hardware Watchdog Driver for TXx9 SoCs
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*
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* Copyright (C) 2007 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/module.h>
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#include <linux/moduleparam.h>
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#include <linux/types.h>
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#include <linux/watchdog.h>
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#include <linux/init.h>
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#include <linux/platform_device.h>
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#include <linux/clk.h>
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#include <linux/err.h>
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#include <linux/io.h>
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#include <asm/txx9tmr.h>
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#define WD_TIMER_CCD 7 /* 1/256 */
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#define WD_TIMER_CLK (clk_get_rate(txx9_imclk) / (2 << WD_TIMER_CCD))
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#define WD_MAX_TIMEOUT ((0xffffffff >> (32 - TXX9_TIMER_BITS)) / WD_TIMER_CLK)
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#define TIMER_MARGIN 60 /* Default is 60 seconds */
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static unsigned int timeout = TIMER_MARGIN; /* in seconds */
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module_param(timeout, uint, 0);
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MODULE_PARM_DESC(timeout,
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"Watchdog timeout in seconds. "
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"(0<timeout<((2^" __MODULE_STRING(TXX9_TIMER_BITS) ")/(IMCLK/256)), "
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"default=" __MODULE_STRING(TIMER_MARGIN) ")");
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static bool nowayout = WATCHDOG_NOWAYOUT;
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module_param(nowayout, bool, 0);
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MODULE_PARM_DESC(nowayout,
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"Watchdog cannot be stopped once started "
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"(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
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static struct txx9_tmr_reg __iomem *txx9wdt_reg;
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static struct clk *txx9_imclk;
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static DEFINE_SPINLOCK(txx9_lock);
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static int txx9wdt_ping(struct watchdog_device *wdt_dev)
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{
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spin_lock(&txx9_lock);
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__raw_writel(TXx9_TMWTMR_TWIE | TXx9_TMWTMR_TWC, &txx9wdt_reg->wtmr);
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spin_unlock(&txx9_lock);
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return 0;
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}
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static int txx9wdt_start(struct watchdog_device *wdt_dev)
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{
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spin_lock(&txx9_lock);
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__raw_writel(WD_TIMER_CLK * wdt_dev->timeout, &txx9wdt_reg->cpra);
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__raw_writel(WD_TIMER_CCD, &txx9wdt_reg->ccdr);
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__raw_writel(0, &txx9wdt_reg->tisr); /* clear pending interrupt */
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__raw_writel(TXx9_TMTCR_TCE | TXx9_TMTCR_CCDE | TXx9_TMTCR_TMODE_WDOG,
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&txx9wdt_reg->tcr);
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__raw_writel(TXx9_TMWTMR_TWIE | TXx9_TMWTMR_TWC, &txx9wdt_reg->wtmr);
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spin_unlock(&txx9_lock);
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return 0;
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}
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static int txx9wdt_stop(struct watchdog_device *wdt_dev)
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{
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spin_lock(&txx9_lock);
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__raw_writel(TXx9_TMWTMR_WDIS, &txx9wdt_reg->wtmr);
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__raw_writel(__raw_readl(&txx9wdt_reg->tcr) & ~TXx9_TMTCR_TCE,
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&txx9wdt_reg->tcr);
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spin_unlock(&txx9_lock);
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return 0;
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}
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static int txx9wdt_set_timeout(struct watchdog_device *wdt_dev,
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unsigned int new_timeout)
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{
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wdt_dev->timeout = new_timeout;
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txx9wdt_stop(wdt_dev);
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txx9wdt_start(wdt_dev);
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return 0;
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}
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static const struct watchdog_info txx9wdt_info = {
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.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
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.identity = "Hardware Watchdog for TXx9",
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};
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static const struct watchdog_ops txx9wdt_ops = {
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.owner = THIS_MODULE,
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.start = txx9wdt_start,
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.stop = txx9wdt_stop,
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.ping = txx9wdt_ping,
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.set_timeout = txx9wdt_set_timeout,
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};
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static struct watchdog_device txx9wdt = {
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.info = &txx9wdt_info,
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.ops = &txx9wdt_ops,
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};
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static int __init txx9wdt_probe(struct platform_device *dev)
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{
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struct resource *res;
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int ret;
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txx9_imclk = clk_get(NULL, "imbus_clk");
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if (IS_ERR(txx9_imclk)) {
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ret = PTR_ERR(txx9_imclk);
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txx9_imclk = NULL;
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goto exit;
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}
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ret = clk_enable(txx9_imclk);
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if (ret) {
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clk_put(txx9_imclk);
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txx9_imclk = NULL;
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goto exit;
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}
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res = platform_get_resource(dev, IORESOURCE_MEM, 0);
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txx9wdt_reg = devm_ioremap_resource(&dev->dev, res);
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if (IS_ERR(txx9wdt_reg)) {
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ret = PTR_ERR(txx9wdt_reg);
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goto exit;
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}
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if (timeout < 1 || timeout > WD_MAX_TIMEOUT)
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timeout = TIMER_MARGIN;
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txx9wdt.timeout = timeout;
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txx9wdt.min_timeout = 1;
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txx9wdt.max_timeout = WD_MAX_TIMEOUT;
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txx9wdt.parent = &dev->dev;
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watchdog_set_nowayout(&txx9wdt, nowayout);
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ret = watchdog_register_device(&txx9wdt);
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if (ret)
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goto exit;
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pr_info("Hardware Watchdog Timer: timeout=%d sec (max %ld) (nowayout= %d)\n",
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timeout, WD_MAX_TIMEOUT, nowayout);
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return 0;
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exit:
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if (txx9_imclk) {
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clk_disable(txx9_imclk);
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clk_put(txx9_imclk);
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}
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return ret;
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}
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static int __exit txx9wdt_remove(struct platform_device *dev)
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{
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watchdog_unregister_device(&txx9wdt);
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clk_disable(txx9_imclk);
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clk_put(txx9_imclk);
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return 0;
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}
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static void txx9wdt_shutdown(struct platform_device *dev)
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{
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txx9wdt_stop(&txx9wdt);
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}
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static struct platform_driver txx9wdt_driver = {
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.remove = __exit_p(txx9wdt_remove),
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.shutdown = txx9wdt_shutdown,
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.driver = {
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.name = "txx9wdt",
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},
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};
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module_platform_driver_probe(txx9wdt_driver, txx9wdt_probe);
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MODULE_DESCRIPTION("TXx9 Watchdog Driver");
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MODULE_LICENSE("GPL");
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MODULE_ALIAS("platform:txx9wdt");
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