From 26ee47411ae22caa07d3f3b63ca6d097cba6681b Mon Sep 17 00:00:00 2001 From: Lars-Peter Clausen Date: Wed, 28 Aug 2013 17:55:07 +0200 Subject: [PATCH] regmap: debugfs: Fix continued read from registers file The regmap_debugfs_get_dump_start() function maps from a file offset to the register that can be found at that position in the file. This is done using a look-up table. Commit d6814a7d ("regmap: debugfs: Suppress cache for partial register files") added a check to bypass the look-up table for partial register files, since the offsets in that table are only correct for the full register file. The check incorrectly uses the file offset instead of the register base address and returns it. This will cause the file offset to be interpreted as a register address which will result in a incorrect output from the registers file for all reads except at position 0. The issue can easily be reproduced by doing small reads the registers file, e.g. `dd if=registers bs=10 count=5`. Signed-off-by: Lars-Peter Clausen Signed-off-by: Mark Brown Cc: stable@vger.kernel.org --- drivers/base/regmap/regmap-debugfs.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c index 53495753fbdb..6c2652a8ad50 100644 --- a/drivers/base/regmap/regmap-debugfs.c +++ b/drivers/base/regmap/regmap-debugfs.c @@ -85,8 +85,8 @@ static unsigned int regmap_debugfs_get_dump_start(struct regmap *map, unsigned int reg_offset; /* Suppress the cache if we're using a subrange */ - if (from) - return from; + if (base) + return base; /* * If we don't have a cache build one so we don't have to do a -- 2.34.1