linux/drivers/watchdog/atlas7_wdt.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
* Watchdog driver for CSR Atlas7
*
* Copyright (c) 2015 Cambridge Silicon Radio Limited, a CSR plc group company.
*/
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/watchdog.h>
#define ATLAS7_TIMER_WDT_INDEX 5
#define ATLAS7_WDT_DEFAULT_TIMEOUT 20
#define ATLAS7_WDT_CNT_CTRL (0 + 4 * ATLAS7_TIMER_WDT_INDEX)
#define ATLAS7_WDT_CNT_MATCH (0x18 + 4 * ATLAS7_TIMER_WDT_INDEX)
#define ATLAS7_WDT_CNT (0x48 + 4 * ATLAS7_TIMER_WDT_INDEX)
#define ATLAS7_WDT_CNT_EN (BIT(0) | BIT(1))
#define ATLAS7_WDT_EN 0x64
static unsigned int timeout = ATLAS7_WDT_DEFAULT_TIMEOUT;
static bool nowayout = WATCHDOG_NOWAYOUT;
module_param(timeout, uint, 0);
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(timeout, "Default watchdog timeout (in seconds)");
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
struct atlas7_wdog {
struct device *dev;
void __iomem *base;
unsigned long tick_rate;
struct clk *clk;
};
static unsigned int atlas7_wdt_gettimeleft(struct watchdog_device *wdd)
{
struct atlas7_wdog *wdt = watchdog_get_drvdata(wdd);
u32 counter, match, delta;
counter = readl(wdt->base + ATLAS7_WDT_CNT);
match = readl(wdt->base + ATLAS7_WDT_CNT_MATCH);
delta = match - counter;
return delta / wdt->tick_rate;
}
static int atlas7_wdt_ping(struct watchdog_device *wdd)
{
struct atlas7_wdog *wdt = watchdog_get_drvdata(wdd);
u32 counter, match, delta;
counter = readl(wdt->base + ATLAS7_WDT_CNT);
delta = wdd->timeout * wdt->tick_rate;
match = counter + delta;
writel(match, wdt->base + ATLAS7_WDT_CNT_MATCH);
return 0;
}
static int atlas7_wdt_enable(struct watchdog_device *wdd)
{
struct atlas7_wdog *wdt = watchdog_get_drvdata(wdd);
atlas7_wdt_ping(wdd);
writel(readl(wdt->base + ATLAS7_WDT_CNT_CTRL) | ATLAS7_WDT_CNT_EN,
wdt->base + ATLAS7_WDT_CNT_CTRL);
writel(1, wdt->base + ATLAS7_WDT_EN);
return 0;
}
static int atlas7_wdt_disable(struct watchdog_device *wdd)
{
struct atlas7_wdog *wdt = watchdog_get_drvdata(wdd);
writel(0, wdt->base + ATLAS7_WDT_EN);
writel(readl(wdt->base + ATLAS7_WDT_CNT_CTRL) & ~ATLAS7_WDT_CNT_EN,
wdt->base + ATLAS7_WDT_CNT_CTRL);
return 0;
}
static int atlas7_wdt_settimeout(struct watchdog_device *wdd, unsigned int to)
{
wdd->timeout = to;
return 0;
}
#define OPTIONS (WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE)
static const struct watchdog_info atlas7_wdt_ident = {
.options = OPTIONS,
.firmware_version = 0,
.identity = "atlas7 Watchdog",
};
watchdog: constify watchdog_ops structures Declare watchdog_ops structures as const as they are only stored in the ops field of a watchdog_device structure. This field is of type const, so watchdog_ops structures having this property can be made const too. Done using Coccinelle: @r disable optional_qualifier@ identifier x; position p; @@ static struct watchdog_ops x@p={...}; @ok@ struct watchdog_device w; identifier r.x; position p; @@ w.ops=&x@p; @bad@ position p != {r.p,ok.p}; identifier r.x; @@ x@p @depends on !bad disable optional_qualifier@ identifier r.x; @@ +const struct watchdog_ops x; File size details before and after patching. First line of every .o file shows the file size before patching and second line shows the size after patching. text data bss dec hex filename 1340 544 0 1884 75c drivers/watchdog/bcm_kona_wdt.o 1436 440 0 1876 754 drivers/watchdog/bcm_kona_wdt.o 1176 544 4 1724 6bc drivers/watchdog/digicolor_wdt.o 1272 440 4 1716 6b4 drivers/watchdog/digicolor_wdt.o 925 580 89 1594 63a drivers/watchdog/ep93xx_wdt.o 1021 476 89 1586 632 drivers/watchdog/ep93xx_wdt.o 4932 288 17 5237 1475 drivers/watchdog/s3c2410_wdt.o 5028 192 17 5237 1475 drivers/watchdog/s3c2410_wdt.o 1977 292 1 2270 8de drivers/watchdog/sama5d4_wdt.o 2073 196 1 2270 8de drivers/watchdog/sama5d4_wdt.o 1375 484 1 1860 744 drivers/watchdog/sirfsoc_wdt.o 1471 380 1 1852 73c drivers/watchdog/sirfsoc_wdt.o Size remains the same for the files drivers/watchdog/diag288_wdt.o drivers/watchdog/asm9260_wdt.o and drivers/watchdog/atlas7_wdt.o The following .o files did not compile: drivers/watchdog/sun4v_wdt.o, drivers/watchdog/sbsa_gwdt.o, drivers/watchdog/rt2880_wdt.o, drivers/watchdog/booke_wdt.o drivers/watchdog/mt7621_wdt.o Signed-off-by: Bhumika Goyal <bhumirks@gmail.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-01-28 07:41:17 +00:00
static const struct watchdog_ops atlas7_wdt_ops = {
.owner = THIS_MODULE,
.start = atlas7_wdt_enable,
.stop = atlas7_wdt_disable,
.get_timeleft = atlas7_wdt_gettimeleft,
.ping = atlas7_wdt_ping,
.set_timeout = atlas7_wdt_settimeout,
};
static struct watchdog_device atlas7_wdd = {
.info = &atlas7_wdt_ident,
.ops = &atlas7_wdt_ops,
.timeout = ATLAS7_WDT_DEFAULT_TIMEOUT,
};
static const struct of_device_id atlas7_wdt_ids[] = {
{ .compatible = "sirf,atlas7-tick"},
{}
};
static void atlas7_clk_disable_unprepare(void *data)
{
clk_disable_unprepare(data);
}
static int atlas7_wdt_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct atlas7_wdog *wdt;
struct clk *clk;
int ret;
wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
if (!wdt)
return -ENOMEM;
watchdog: Convert to use devm_platform_ioremap_resource Use devm_platform_ioremap_resource to reduce source code size, improve readability, and reduce the likelyhood of bugs. The conversion was done automatically with coccinelle using the following semantic patch. @r@ identifier res, pdev; expression a; expression index; expression e; @@ <+... - res = platform_get_resource(pdev, IORESOURCE_MEM, index); - a = devm_ioremap_resource(e, res); + a = devm_platform_ioremap_resource(pdev, index); ...+> @depends on r@ identifier r.res; @@ - struct resource *res; ... when != res @@ identifier res, pdev; expression index; expression a; @@ - struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, index); - a = devm_ioremap_resource(&pdev->dev, res); + a = devm_platform_ioremap_resource(pdev, index); Cc: Joel Stanley <joel@jms.id.au> Cc: Nicolas Ferre <nicolas.ferre@microchip.com> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Baruch Siach <baruch@tkos.co.il> Cc: Keguang Zhang <keguang.zhang@gmail.com> Cc: Vladimir Zapolskiy <vz@mleia.com> Cc: Kevin Hilman <khilman@baylibre.com> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: Avi Fishman <avifishman70@gmail.com> Cc: Nancy Yuen <yuenn@google.com> Cc: Brendan Higgins <brendanhiggins@google.com> Cc: Wan ZongShun <mcuos.com@gmail.com> Cc: Michal Simek <michal.simek@xilinx.com> Cc: Sylvain Lemieux <slemieux.tyco@gmail.com> Cc: Kukjin Kim <kgene@kernel.org> Cc: Barry Song <baohua@kernel.org> Cc: Orson Zhai <orsonzhai@gmail.com> Cc: Patrice Chotard <patrice.chotard@st.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Maxime Ripard <maxime.ripard@bootlin.com> Cc: Chen-Yu Tsai <wens@csie.org> Cc: Marc Gonzalez <marc.w.gonzalez@free.fr> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Tested-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Acked-by: Joel Stanley <joel@jms.id.au> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Maxime Ripard <maxime.ripard@bootlin.com> Acked-by: Michal Simek <michal.simek@xilinx.com> (cadence/xilinx wdts) Acked-by: Thierry Reding <treding@nvidia.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Acked-by: Patrice Chotard <patrice.chotard@st.com> Acked-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2019-04-02 19:01:53 +00:00
wdt->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(wdt->base))
return PTR_ERR(wdt->base);
clk = devm_clk_get(dev, NULL);
if (IS_ERR(clk))
return PTR_ERR(clk);
ret = clk_prepare_enable(clk);
if (ret) {
dev_err(dev, "clk enable failed\n");
return ret;
}
ret = devm_add_action_or_reset(dev, atlas7_clk_disable_unprepare, clk);
if (ret)
return ret;
/* disable watchdog hardware */
writel(0, wdt->base + ATLAS7_WDT_CNT_CTRL);
wdt->tick_rate = clk_get_rate(clk);
if (!wdt->tick_rate)
return -EINVAL;
wdt->clk = clk;
atlas7_wdd.min_timeout = 1;
atlas7_wdd.max_timeout = UINT_MAX / wdt->tick_rate;
watchdog_init_timeout(&atlas7_wdd, 0, dev);
watchdog_set_nowayout(&atlas7_wdd, nowayout);
watchdog_set_drvdata(&atlas7_wdd, wdt);
platform_set_drvdata(pdev, &atlas7_wdd);
watchdog_stop_on_reboot(&atlas7_wdd);
watchdog_stop_on_unregister(&atlas7_wdd);
return devm_watchdog_register_device(dev, &atlas7_wdd);
}
static int __maybe_unused atlas7_wdt_suspend(struct device *dev)
{
/*
* NOTE:timer controller registers settings are saved
* and restored back by the timer-atlas7.c
*/
return 0;
}
static int __maybe_unused atlas7_wdt_resume(struct device *dev)
{
struct watchdog_device *wdd = dev_get_drvdata(dev);
/*
* NOTE: Since timer controller registers settings are saved
* and restored back by the timer-atlas7.c, so we need not
* update WD settings except refreshing timeout.
*/
atlas7_wdt_ping(wdd);
return 0;
}
static SIMPLE_DEV_PM_OPS(atlas7_wdt_pm_ops,
atlas7_wdt_suspend, atlas7_wdt_resume);
MODULE_DEVICE_TABLE(of, atlas7_wdt_ids);
static struct platform_driver atlas7_wdt_driver = {
.driver = {
.name = "atlas7-wdt",
.pm = &atlas7_wdt_pm_ops,
.of_match_table = atlas7_wdt_ids,
},
.probe = atlas7_wdt_probe,
};
module_platform_driver(atlas7_wdt_driver);
MODULE_DESCRIPTION("CSRatlas7 watchdog driver");
MODULE_AUTHOR("Guo Zeng <Guo.Zeng@csr.com>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:atlas7-wdt");