linux-stable/drivers/watchdog/atlas7_wdt.c
Bhumika Goyal b893e344bf 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>
2017-02-24 14:00:23 -08:00

247 lines
5.8 KiB
C

/*
* Watchdog driver for CSR Atlas7
*
* Copyright (c) 2015 Cambridge Silicon Radio Limited, a CSR plc group company.
*
* Licensed under GPLv2.
*/
#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",
};
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 int atlas7_wdt_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct atlas7_wdog *wdt;
struct resource *res;
struct clk *clk;
int ret;
wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
if (!wdt)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
wdt->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(wdt->base))
return PTR_ERR(wdt->base);
clk = of_clk_get(np, 0);
if (IS_ERR(clk))
return PTR_ERR(clk);
ret = clk_prepare_enable(clk);
if (ret) {
dev_err(&pdev->dev, "clk enable failed\n");
goto err;
}
/* disable watchdog hardware */
writel(0, wdt->base + ATLAS7_WDT_CNT_CTRL);
wdt->tick_rate = clk_get_rate(clk);
if (!wdt->tick_rate) {
ret = -EINVAL;
goto err1;
}
wdt->clk = clk;
atlas7_wdd.min_timeout = 1;
atlas7_wdd.max_timeout = UINT_MAX / wdt->tick_rate;
watchdog_init_timeout(&atlas7_wdd, 0, &pdev->dev);
watchdog_set_nowayout(&atlas7_wdd, nowayout);
watchdog_set_drvdata(&atlas7_wdd, wdt);
platform_set_drvdata(pdev, &atlas7_wdd);
ret = watchdog_register_device(&atlas7_wdd);
if (ret)
goto err1;
return 0;
err1:
clk_disable_unprepare(clk);
err:
clk_put(clk);
return ret;
}
static void atlas7_wdt_shutdown(struct platform_device *pdev)
{
struct watchdog_device *wdd = platform_get_drvdata(pdev);
struct atlas7_wdog *wdt = watchdog_get_drvdata(wdd);
atlas7_wdt_disable(wdd);
clk_disable_unprepare(wdt->clk);
}
static int atlas7_wdt_remove(struct platform_device *pdev)
{
struct watchdog_device *wdd = platform_get_drvdata(pdev);
struct atlas7_wdog *wdt = watchdog_get_drvdata(wdd);
atlas7_wdt_shutdown(pdev);
clk_put(wdt->clk);
return 0;
}
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,
.remove = atlas7_wdt_remove,
.shutdown = atlas7_wdt_shutdown,
};
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");