public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Lars-Peter Clausen <lars@metafoo.de>
To: Michal Simek <michal.simek@xilinx.com>
Cc: linux-kernel@vger.kernel.org, monstr@monstr.eu,
	Arnd Bergmann <arnd@arndb.de>, Mark Brown <broonie@kernel.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Subject: Re: [PATCH] regmap: Check readable regs in _regmap_read
Date: Mon, 10 Feb 2014 11:53:38 +0100	[thread overview]
Message-ID: <52F8AFB2.4000307@metafoo.de> (raw)
In-Reply-To: <73e82a7cf77a1a68c5303def3071418b7d0ea382.1392029156.git.michal.simek@xilinx.com>

On 02/10/2014 11:46 AM, Michal Simek wrote:
> Check if regs are readable.
>
> Signed-off-by: Michal Simek <michal.simek@xilinx.com>
> ---
>
>   drivers/base/regmap/regmap.c | 3 +++
>   1 file changed, 3 insertions(+)
>
> diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
> index 6a19515..7569dfc 100644
> --- a/drivers/base/regmap/regmap.c
> +++ b/drivers/base/regmap/regmap.c
> @@ -1725,6 +1725,9 @@ static int _regmap_read(struct regmap *map, unsigned int reg,
>   	int ret;
>   	void *context = _regmap_map_get_context(map);
>
> +	if (!regmap_readable(map, reg))
> +		return -EIO;
> +

This will cause issues with devices where registers are writable, but not 
readable, but we keep the register value in the cache.

>   	WARN_ON(!map->reg_read);
>
>   	if (!map->cache_bypass) {
> --
> 1.8.2.3
>


  reply	other threads:[~2014-02-10 10:53 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-02-10 10:46 [PATCH] regmap: Check readable regs in _regmap_read Michal Simek
2014-02-10 10:53 ` Lars-Peter Clausen [this message]
2014-02-10 11:00   ` Michal Simek
2014-02-10 11:49   ` Mark Brown
2014-02-10 11:54     ` Michal Simek

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=52F8AFB2.4000307@metafoo.de \
    --to=lars@metafoo.de \
    --cc=arnd@arndb.de \
    --cc=broonie@kernel.org \
    --cc=gregkh@linuxfoundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=michal.simek@xilinx.com \
    --cc=monstr@monstr.eu \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox