All of lore.kernel.org
 help / color / mirror / Atom feed
From: Guenter Roeck <linux@roeck-us.net>
To: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Wim Van Sebroeck <wim@iguana.be>,
	Nicolas Ferre <nicolas.ferre@microchip.com>,
	Wenyou.Yang@microchip.com, linux-watchdog@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 4/4] watchdog: sama5d4: Add comment explaining what happens on resume
Date: Sat, 4 Mar 2017 07:07:28 -0800	[thread overview]
Message-ID: <d97f8e83-7fdd-61e5-01c9-af089f92b71d@roeck-us.net> (raw)
In-Reply-To: <20170302173114.28508-5-alexandre.belloni@free-electrons.com>

On 03/02/2017 09:31 AM, Alexandre Belloni wrote:
> Because suspending to RAM may lose the register values, they are restored
> on resume. This is currently done unconditionally because there is
> currently no way to know (from the driver) whether they have really been
> lost or are still valid. Writing MR also pings the watchdog and this may
> not be what is expected so add a comment explaining why it happens.
>
> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> ---
>  drivers/watchdog/sama5d4_wdt.c | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/drivers/watchdog/sama5d4_wdt.c b/drivers/watchdog/sama5d4_wdt.c
> index d710014f3b7d..0ae947c3d7bc 100644
> --- a/drivers/watchdog/sama5d4_wdt.c
> +++ b/drivers/watchdog/sama5d4_wdt.c
> @@ -300,6 +300,11 @@ static int sama5d4_wdt_resume(struct device *dev)
>  {
>  	struct sama5d4_wdt *wdt = dev_get_drvdata(dev);
>
> +	/*
> +	 * FIXME: writing MR also pings the watchdog which may not be desired.
> +	 * This should only be done when the registers are lost on suspend but
> +	 * there is no way to get this information right now.
> +	 */
>  	sama5d4_wdt_init(wdt);
>
>  	return 0;
>

WARNING: multiple messages have this Message-ID (diff)
From: linux@roeck-us.net (Guenter Roeck)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 4/4] watchdog: sama5d4: Add comment explaining what happens on resume
Date: Sat, 4 Mar 2017 07:07:28 -0800	[thread overview]
Message-ID: <d97f8e83-7fdd-61e5-01c9-af089f92b71d@roeck-us.net> (raw)
In-Reply-To: <20170302173114.28508-5-alexandre.belloni@free-electrons.com>

On 03/02/2017 09:31 AM, Alexandre Belloni wrote:
> Because suspending to RAM may lose the register values, they are restored
> on resume. This is currently done unconditionally because there is
> currently no way to know (from the driver) whether they have really been
> lost or are still valid. Writing MR also pings the watchdog and this may
> not be what is expected so add a comment explaining why it happens.
>
> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> ---
>  drivers/watchdog/sama5d4_wdt.c | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/drivers/watchdog/sama5d4_wdt.c b/drivers/watchdog/sama5d4_wdt.c
> index d710014f3b7d..0ae947c3d7bc 100644
> --- a/drivers/watchdog/sama5d4_wdt.c
> +++ b/drivers/watchdog/sama5d4_wdt.c
> @@ -300,6 +300,11 @@ static int sama5d4_wdt_resume(struct device *dev)
>  {
>  	struct sama5d4_wdt *wdt = dev_get_drvdata(dev);
>
> +	/*
> +	 * FIXME: writing MR also pings the watchdog which may not be desired.
> +	 * This should only be done when the registers are lost on suspend but
> +	 * there is no way to get this information right now.
> +	 */
>  	sama5d4_wdt_init(wdt);
>
>  	return 0;
>

  reply	other threads:[~2017-03-04 15:07 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-03-02 17:31 [PATCH 0/4] watchdog: sama5d4: fix issues Alexandre Belloni
2017-03-02 17:31 ` Alexandre Belloni
2017-03-02 17:31 ` [PATCH 1/4] watchdog: sama5d4: fix WDDIS handling Alexandre Belloni
2017-03-02 17:31   ` Alexandre Belloni
2017-03-04 15:04   ` Guenter Roeck
2017-03-04 15:04     ` Guenter Roeck
2017-03-07  2:05   ` Wenyou.Yang
2017-03-07  2:05     ` Wenyou.Yang at microchip.com
2017-03-02 17:31 ` [PATCH 2/4] watchdog: sama5d4: fix race condition Alexandre Belloni
2017-03-02 17:31   ` Alexandre Belloni
2017-03-02 17:42   ` Guenter Roeck
2017-03-02 17:42     ` Guenter Roeck
2017-03-02 17:54     ` Alexandre Belloni
2017-03-02 17:54       ` Alexandre Belloni
2017-03-04 15:05   ` Guenter Roeck
2017-03-04 15:05     ` Guenter Roeck
2017-03-07  2:06   ` Wenyou.Yang
2017-03-07  2:06     ` Wenyou.Yang at microchip.com
2017-03-02 17:31 ` [PATCH 3/4] watchodg: sama5d4: simplify probe Alexandre Belloni
2017-03-02 17:31   ` Alexandre Belloni
2017-03-02 19:29   ` Alexander Dahl
2017-03-02 19:29     ` Alexander Dahl
2017-03-03  8:03   ` Thomas Petazzoni
2017-03-03  8:03     ` Thomas Petazzoni
2017-03-03  9:29     ` Alexandre Belloni
2017-03-03  9:29       ` Alexandre Belloni
2017-03-03 14:14       ` Guenter Roeck
2017-03-03 14:14         ` Guenter Roeck
2017-03-04 15:06   ` Guenter Roeck
2017-03-04 15:06     ` Guenter Roeck
2017-03-02 17:31 ` [PATCH 4/4] watchdog: sama5d4: Add comment explaining what happens on resume Alexandre Belloni
2017-03-02 17:31   ` Alexandre Belloni
2017-03-04 15:07   ` Guenter Roeck [this message]
2017-03-04 15:07     ` Guenter Roeck

Reply instructions:

You may reply publicly 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=d97f8e83-7fdd-61e5-01c9-af089f92b71d@roeck-us.net \
    --to=linux@roeck-us.net \
    --cc=Wenyou.Yang@microchip.com \
    --cc=alexandre.belloni@free-electrons.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-watchdog@vger.kernel.org \
    --cc=nicolas.ferre@microchip.com \
    --cc=wim@iguana.be \
    /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
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.