Linux-Watchdog Archive on lore.kernel.org
 help / color / Atom feed
From: Guenter Roeck <linux@roeck-us.net>
To: Brandon Maier <brandon.maier@rockwellcollins.com>,
	linux-watchdog@vger.kernel.org
Cc: wim@linux-watchdog.org
Subject: Re: [PATCH] watchdog: omap: Fix early_enable to start watchdogd
Date: Sun, 17 Nov 2019 13:44:51 -0800
Message-ID: <6e9a6f3b-0723-ac59-b859-f8b7b75d39a9@roeck-us.net> (raw)
In-Reply-To: <20191117200325.142419-1-brandon.maier@rockwellcollins.com>

On 11/17/19 12:03 PM, Brandon Maier wrote:
> When the 'early_enable' module_param is enabled, Linux's watchdogd
> thread does not start, causing the watchdog to eventually fire.
> 

What does early_enable have to do with watchdogd ? Why would
watchdogd not start if this flag is set ?

The purpose of early_enable in this driver, as I understand it,
was to force watchdogd to start within the timeout period. So
it does exactly what it is supposed to be doing.

Guenter

> For the watchdogd to be started, the WDOG_HW_RUNNING flag must be set
> before watchdog_register_device().
> 
> Signed-off-by: Brandon Maier <brandon.maier@rockwellcollins.com>
> ---
>   drivers/watchdog/omap_wdt.c | 10 ++++++----
>   1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/watchdog/omap_wdt.c b/drivers/watchdog/omap_wdt.c
> index 9b91882fe3c4..ecc8592c00a5 100644
> --- a/drivers/watchdog/omap_wdt.c
> +++ b/drivers/watchdog/omap_wdt.c
> @@ -268,8 +268,13 @@ static int omap_wdt_probe(struct platform_device *pdev)
>   			wdev->wdog.bootstatus = WDIOF_CARDRESET;
>   	}
>   
> -	if (!early_enable)
> +	if (!early_enable) {
>   		omap_wdt_disable(wdev);
> +		clear_bit(WDOG_HW_RUNNING, &wdev->wdog.status);
> +	} else {
> +		omap_wdt_start(&wdev->wdog);
> +		set_bit(WDOG_HW_RUNNING, &wdev->wdog.status);
> +	}
>   
>   	ret = watchdog_register_device(&wdev->wdog);
>   	if (ret) {
> @@ -281,9 +286,6 @@ static int omap_wdt_probe(struct platform_device *pdev)
>   		readl_relaxed(wdev->base + OMAP_WATCHDOG_REV) & 0xFF,
>   		wdev->wdog.timeout);
>   
> -	if (early_enable)
> -		omap_wdt_start(&wdev->wdog);
> -
>   	pm_runtime_put(wdev->dev);
>   
>   	return 0;
> 


  reply index

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-17 20:03 Brandon Maier
2019-11-17 21:44 ` Guenter Roeck [this message]
2019-11-17 22:19   ` Brandon Maier
2019-11-18  0:23     ` Guenter Roeck
2019-11-18 16:10       ` [External] " Brandon Maier

Reply instructions:

You may reply publically to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=6e9a6f3b-0723-ac59-b859-f8b7b75d39a9@roeck-us.net \
    --to=linux@roeck-us.net \
    --cc=brandon.maier@rockwellcollins.com \
    --cc=linux-watchdog@vger.kernel.org \
    --cc=wim@linux-watchdog.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-Watchdog Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-watchdog/0 linux-watchdog/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-watchdog linux-watchdog/ https://lore.kernel.org/linux-watchdog \
		linux-watchdog@vger.kernel.org
	public-inbox-index linux-watchdog

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-watchdog


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git