cregit-Linux how code gets into the kernel

Release 4.7 drivers/watchdog/tangox_wdt.c

Directory: drivers/watchdog
/*
 *  Copyright (C) 2015 Mans Rullgard <mans@mansr.com>
 *  SMP86xx/SMP87xx Watchdog driver
 *
 *  This program is free software; you can redistribute it and/or modify it
 *  under  the terms of the GNU General  Public License as published by the
 *  Free Software Foundation;  either version 2 of the License, or (at your
 *  option) any later version.
 */

#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/notifier.h>
#include <linux/platform_device.h>
#include <linux/reboot.h>
#include <linux/watchdog.h>


#define DEFAULT_TIMEOUT 30


static bool nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout,
		 "Watchdog cannot be stopped once started (default="
		 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");


static unsigned int timeout;
module_param(timeout, int, 0);
MODULE_PARM_DESC(timeout, "Watchdog timeout");

/*
 * Counter counts down from programmed value.  Reset asserts when
 * the counter reaches 1.
 */

#define WD_COUNTER		0


#define WD_CONFIG		4

#define WD_CONFIG_XTAL_IN	BIT(0)

#define WD_CONFIG_DISABLE	BIT(31)


struct tangox_wdt_device {
	
struct watchdog_device wdt;
	
void __iomem *base;
	
unsigned long clk_rate;
	
struct clk *clk;
	
struct notifier_block restart;
};


static int tangox_wdt_set_timeout(struct watchdog_device *wdt, unsigned int new_timeout) { wdt->timeout = new_timeout; return 0; }

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mans rullgardmans rullgard24100.00%1100.00%
Total24100.00%1100.00%


static int tangox_wdt_start(struct watchdog_device *wdt) { struct tangox_wdt_device *dev = watchdog_get_drvdata(wdt); u32 ticks; ticks = 1 + wdt->timeout * dev->clk_rate; writel(ticks, dev->base + WD_COUNTER); return 0; }

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mans rullgardmans rullgard50100.00%1100.00%
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static int tangox_wdt_stop(struct watchdog_device *wdt) { struct tangox_wdt_device *dev = watchdog_get_drvdata(wdt); writel(0, dev->base + WD_COUNTER); return 0; }

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mans rullgardmans rullgard35100.00%1100.00%
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static unsigned int tangox_wdt_get_timeleft(struct watchdog_device *wdt) { struct tangox_wdt_device *dev = watchdog_get_drvdata(wdt); u32 count; count = readl(dev->base + WD_COUNTER); if (!count) return 0; return (count - 1) / dev->clk_rate; }

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mans rullgardmans rullgard55100.00%1100.00%
Total55100.00%1100.00%

static const struct watchdog_info tangox_wdt_info = { .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, .identity = "tangox watchdog", }; static const struct watchdog_ops tangox_wdt_ops = { .start = tangox_wdt_start, .stop = tangox_wdt_stop, .set_timeout = tangox_wdt_set_timeout, .get_timeleft = tangox_wdt_get_timeleft, };
static int tangox_wdt_restart(struct notifier_block *nb, unsigned long action, void *data) { struct tangox_wdt_device *dev = container_of(nb, struct tangox_wdt_device, restart); writel(1, dev->base + WD_COUNTER); return NOTIFY_DONE; }

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mans rullgardmans rullgard48100.00%1100.00%
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static int tangox_wdt_probe(struct platform_device *pdev) { struct tangox_wdt_device *dev; struct resource *res; u32 config; int err; dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL); if (!dev) return -ENOMEM; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); dev->base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(dev->base)) return PTR_ERR(dev->base); dev->clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(dev->clk)) return PTR_ERR(dev->clk); err = clk_prepare_enable(dev->clk); if (err) return err; dev->clk_rate = clk_get_rate(dev->clk); if (!dev->clk_rate) { err = -EINVAL; goto err; } dev->wdt.parent = &pdev->dev; dev->wdt.info = &tangox_wdt_info; dev->wdt.ops = &tangox_wdt_ops; dev->wdt.timeout = DEFAULT_TIMEOUT; dev->wdt.min_timeout = 1; dev->wdt.max_timeout = (U32_MAX - 1) / dev->clk_rate; watchdog_init_timeout(&dev->wdt, timeout, &pdev->dev); watchdog_set_nowayout(&dev->wdt, nowayout); watchdog_set_drvdata(&dev->wdt, dev); /* * Deactivate counter if disable bit is set to avoid * accidental reset. */ config = readl(dev->base + WD_CONFIG); if (config & WD_CONFIG_DISABLE) writel(0, dev->base + WD_COUNTER); writel(WD_CONFIG_XTAL_IN, dev->base + WD_CONFIG); /* * Mark as active and restart with configured timeout if * already running. */ if (readl(dev->base + WD_COUNTER)) { set_bit(WDOG_ACTIVE, &dev->wdt.status); tangox_wdt_start(&dev->wdt); } err = watchdog_register_device(&dev->wdt); if (err) goto err; platform_set_drvdata(pdev, dev); dev->restart.notifier_call = tangox_wdt_restart; dev->restart.priority = 128; err = register_restart_handler(&dev->restart); if (err) dev_warn(&pdev->dev, "failed to register restart handler\n"); dev_info(&pdev->dev, "SMP86xx/SMP87xx watchdog registered\n"); return 0; err: clk_disable_unprepare(dev->clk); return err; }

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mans rullgardmans rullgard39792.33%133.33%
wolfram sangwolfram sang317.21%133.33%
guenter roeckguenter roeck20.47%133.33%
Total430100.00%3100.00%


static int tangox_wdt_remove(struct platform_device *pdev) { struct tangox_wdt_device *dev = platform_get_drvdata(pdev); tangox_wdt_stop(&dev->wdt); clk_disable_unprepare(dev->clk); unregister_restart_handler(&dev->restart); watchdog_unregister_device(&dev->wdt); return 0; }

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mans rullgardmans rullgard55100.00%1100.00%
Total55100.00%1100.00%

static const struct of_device_id tangox_wdt_dt_ids[] = { { .compatible = "sigma,smp8642-wdt" }, { .compatible = "sigma,smp8759-wdt" }, { } }; MODULE_DEVICE_TABLE(of, tangox_wdt_dt_ids); static struct platform_driver tangox_wdt_driver = { .probe = tangox_wdt_probe, .remove = tangox_wdt_remove, .driver = { .name = "tangox-wdt", .of_match_table = tangox_wdt_dt_ids, }, }; module_platform_driver(tangox_wdt_driver); MODULE_AUTHOR("Mans Rullgard <mans@mansr.com>"); MODULE_DESCRIPTION("SMP86xx/SMP87xx Watchdog driver"); MODULE_LICENSE("GPL");

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mans rullgardmans rullgard92896.57%133.33%
wolfram sangwolfram sang313.23%133.33%
guenter roeckguenter roeck20.21%133.33%
Total961100.00%3100.00%
Directory: drivers/watchdog
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