Re: [v2,4/4] watchdog: aspeed: Move init to arch_initcall

From: Guenter Roeck
Date: Sun Oct 22 2017 - 12:13:40 EST


On Wed, Sep 20, 2017 at 03:00:20PM +0930, Andrew Jeffery wrote:
> Probing at device_initcall time lead to perverse cases where the
> watchdog was probed after, say, I2C devices, which then leaves a
> potentially running watchdog at the mercy of I2C device behaviour and
> bus conditions.
>
> Load the watchdog driver early to ensure that the kernel is patting it
> well before initialising peripherals.
>
> Signed-off-by: Andrew Jeffery <andrew@xxxxxxxx>

At some point we'll need to come up with a generic means to handle those
situations. Until then, I don't have a better idea.

Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>

> ---
> drivers/watchdog/aspeed_wdt.c | 13 ++++++++++++-
> 1 file changed, 12 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/watchdog/aspeed_wdt.c b/drivers/watchdog/aspeed_wdt.c
> index 6c6dd3f4c48d..ca5b91e2eb92 100644
> --- a/drivers/watchdog/aspeed_wdt.c
> +++ b/drivers/watchdog/aspeed_wdt.c
> @@ -316,7 +316,18 @@ static struct platform_driver aspeed_watchdog_driver = {
> .of_match_table = of_match_ptr(aspeed_wdt_of_table),
> },
> };
> -module_platform_driver(aspeed_watchdog_driver);
> +
> +static int __init aspeed_wdt_init(void)
> +{
> + return platform_driver_register(&aspeed_watchdog_driver);
> +}
> +arch_initcall(aspeed_wdt_init);
> +
> +static void __exit aspeed_wdt_exit(void)
> +{
> + platform_driver_unregister(&aspeed_watchdog_driver);
> +}
> +module_exit(aspeed_wdt_exit);
>
> MODULE_DESCRIPTION("Aspeed Watchdog Driver");
> MODULE_LICENSE("GPL");