linux/drivers/watchdog/ux500_wdt.c
Jean Delvare 487722cf2d watchdog: Get rid of MODULE_ALIAS_MISCDEV statements
I just can't find any value in MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR)
and MODULE_ALIAS_MISCDEV(TEMP_MINOR) statements.

Either the device is enumerated and the driver already has a module
alias (e.g. PCI, USB etc.) that will get the right driver loaded
automatically.

Or the device is not enumerated and loading its driver will lead to
more or less intrusive hardware poking. Such hardware poking should be
limited to a bare minimum, so the user should really decide which
drivers should be tried and in what order. Trying them all in
arbitrary order can't do any good.

On top of that, loading that many drivers at once bloats the kernel
log. Also many drivers will stay loaded afterward, bloating the output
of "lsmod" and wasting memory. Some modules (cs5535_mfgpt which gets
loaded as a dependency) can't even be unloaded!

If defining char-major-10-130 is needed then it should happen in
user-space.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Mike Frysinger <vapier.adi@gmail.com>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Zwane Mwaikambo <zwane@arm.linux.org.uk>
Cc: Jim Cromie <jim.cromie@gmail.com>
2013-11-17 19:38:13 +01:00

171 lines
4.0 KiB
C

/*
* Copyright (C) ST-Ericsson SA 2011-2013
*
* License Terms: GNU General Public License v2
*
* Author: Mathieu Poirier <mathieu.poirier@linaro.org> for ST-Ericsson
* Author: Jonas Aaberg <jonas.aberg@stericsson.com> for ST-Ericsson
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/moduleparam.h>
#include <linux/miscdevice.h>
#include <linux/err.h>
#include <linux/uaccess.h>
#include <linux/watchdog.h>
#include <linux/platform_device.h>
#include <linux/platform_data/ux500_wdt.h>
#include <linux/mfd/dbx500-prcmu.h>
#define WATCHDOG_TIMEOUT 600 /* 10 minutes */
#define WATCHDOG_MIN 0
#define WATCHDOG_MAX28 268435 /* 28 bit resolution in ms == 268435.455 s */
#define WATCHDOG_MAX32 4294967 /* 32 bit resolution in ms == 4294967.295 s */
static unsigned int timeout = WATCHDOG_TIMEOUT;
module_param(timeout, uint, 0);
MODULE_PARM_DESC(timeout,
"Watchdog timeout in seconds. default="
__MODULE_STRING(WATCHDOG_TIMEOUT) ".");
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 int ux500_wdt_start(struct watchdog_device *wdd)
{
return prcmu_enable_a9wdog(PRCMU_WDOG_ALL);
}
static int ux500_wdt_stop(struct watchdog_device *wdd)
{
return prcmu_disable_a9wdog(PRCMU_WDOG_ALL);
}
static int ux500_wdt_keepalive(struct watchdog_device *wdd)
{
return prcmu_kick_a9wdog(PRCMU_WDOG_ALL);
}
static int ux500_wdt_set_timeout(struct watchdog_device *wdd,
unsigned int timeout)
{
ux500_wdt_stop(wdd);
prcmu_load_a9wdog(PRCMU_WDOG_ALL, timeout * 1000);
ux500_wdt_start(wdd);
return 0;
}
static const struct watchdog_info ux500_wdt_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
.identity = "Ux500 WDT",
.firmware_version = 1,
};
static const struct watchdog_ops ux500_wdt_ops = {
.owner = THIS_MODULE,
.start = ux500_wdt_start,
.stop = ux500_wdt_stop,
.ping = ux500_wdt_keepalive,
.set_timeout = ux500_wdt_set_timeout,
};
static struct watchdog_device ux500_wdt = {
.info = &ux500_wdt_info,
.ops = &ux500_wdt_ops,
.min_timeout = WATCHDOG_MIN,
.max_timeout = WATCHDOG_MAX32,
};
static int ux500_wdt_probe(struct platform_device *pdev)
{
int ret;
struct ux500_wdt_data *pdata = dev_get_platdata(&pdev->dev);
if (pdata) {
if (pdata->timeout > 0)
timeout = pdata->timeout;
if (pdata->has_28_bits_resolution)
ux500_wdt.max_timeout = WATCHDOG_MAX28;
}
watchdog_set_nowayout(&ux500_wdt, nowayout);
/* disable auto off on sleep */
prcmu_config_a9wdog(PRCMU_WDOG_CPU1, false);
/* set HW initial value */
prcmu_load_a9wdog(PRCMU_WDOG_ALL, timeout * 1000);
ret = watchdog_register_device(&ux500_wdt);
if (ret)
return ret;
dev_info(&pdev->dev, "initialized\n");
return 0;
}
static int ux500_wdt_remove(struct platform_device *dev)
{
watchdog_unregister_device(&ux500_wdt);
return 0;
}
#ifdef CONFIG_PM
static int ux500_wdt_suspend(struct platform_device *pdev,
pm_message_t state)
{
if (watchdog_active(&ux500_wdt)) {
ux500_wdt_stop(&ux500_wdt);
prcmu_config_a9wdog(PRCMU_WDOG_CPU1, true);
prcmu_load_a9wdog(PRCMU_WDOG_ALL, timeout * 1000);
ux500_wdt_start(&ux500_wdt);
}
return 0;
}
static int ux500_wdt_resume(struct platform_device *pdev)
{
if (watchdog_active(&ux500_wdt)) {
ux500_wdt_stop(&ux500_wdt);
prcmu_config_a9wdog(PRCMU_WDOG_CPU1, false);
prcmu_load_a9wdog(PRCMU_WDOG_ALL, timeout * 1000);
ux500_wdt_start(&ux500_wdt);
}
return 0;
}
#else
#define ux500_wdt_suspend NULL
#define ux500_wdt_resume NULL
#endif
static struct platform_driver ux500_wdt_driver = {
.probe = ux500_wdt_probe,
.remove = ux500_wdt_remove,
.suspend = ux500_wdt_suspend,
.resume = ux500_wdt_resume,
.driver = {
.owner = THIS_MODULE,
.name = "ux500_wdt",
},
};
module_platform_driver(ux500_wdt_driver);
MODULE_AUTHOR("Jonas Aaberg <jonas.aberg@stericsson.com>");
MODULE_DESCRIPTION("Ux500 Watchdog Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:ux500_wdt");