mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Mark Brown <broonie@opensource.wolfsonmicro.com>
To: linux-kernel@vger.kernel.org
Cc: patches@opensource.wolfsonmicro.com,
	Mark Brown <broonie@opensource.wolfsonmicro.com>
Subject: [PATCH] regmap: Skip hardware defaults for LZO caches
Date: Thu, 23 Feb 2012 20:12:34 +0000	[thread overview]
Message-ID: <1330027955-30651-1-git-send-email-broonie@opensource.wolfsonmicro.com> (raw)

Saves some I/O when resyncing; we assume that syncs start from the device
reset state.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
---
 drivers/base/regmap/regcache-lzo.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/drivers/base/regmap/regcache-lzo.c b/drivers/base/regmap/regcache-lzo.c
index 5e964e9..77dc532 100644
--- a/drivers/base/regmap/regcache-lzo.c
+++ b/drivers/base/regmap/regcache-lzo.c
@@ -349,6 +349,12 @@ static int regcache_lzo_sync(struct regmap *map, unsigned int min,
 		ret = regcache_read(map, i, &val);
 		if (ret)
 			return ret;
+
+		/* Is this the hardware default?  If so skip. */
+		ret = regcache_lookup_reg(map, i);
+		if (ret > 0 && val == map->reg_defaults[ret].def)
+			continue;
+
 		map->cache_bypass = 1;
 		ret = _regmap_write(map, i, val);
 		map->cache_bypass = 0;
-- 
1.7.9.1


                 reply	other threads:[~2012-02-23 20:12 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

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=1330027955-30651-1-git-send-email-broonie@opensource.wolfsonmicro.com \
    --to=broonie@opensource.wolfsonmicro.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=patches@opensource.wolfsonmicro.com \
    /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

all inboxes | Powered by JetHome®