[PATCH 1/2] regmap: give users _choice_ to allow write access to debugfs

From: Vinod Koul
Date: Thu May 30 2013 - 13:01:44 EST


is very handy is debug kernels and should _never_ be turned On in production
mode

Signed-off-by: Vinod Koul <vinod.koul@xxxxxxxxx>
---
drivers/base/regmap/Kconfig | 9 +++++++++
drivers/base/regmap/regmap-debugfs.c | 3 +--
2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/base/regmap/Kconfig b/drivers/base/regmap/Kconfig
index f0d3054..928d6e3 100644
--- a/drivers/base/regmap/Kconfig
+++ b/drivers/base/regmap/Kconfig
@@ -20,3 +20,12 @@ config REGMAP_MMIO

config REGMAP_IRQ
bool
+
+
+config REGMAP_ALLOW_WRITE_DEBUGFS
+ bool "Regmap write access to usermode"
+ default n
+ help
+ WARNING: This allows usermode to write to hardware registers. Writing
+ to stuff like PMICs is _never_ advised due to obvious side effects, use
+ at very extreme caution. Is helpful for debugging
diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c
index 23b701f..7989052 100644
--- a/drivers/base/regmap/regmap-debugfs.c
+++ b/drivers/base/regmap/regmap-debugfs.c
@@ -248,8 +248,7 @@ static ssize_t regmap_map_read_file(struct file *file, char __user *user_buf,
count, ppos);
}

-#undef REGMAP_ALLOW_WRITE_DEBUGFS
-#ifdef REGMAP_ALLOW_WRITE_DEBUGFS
+#ifdef CONFIG_REGMAP_ALLOW_WRITE_DEBUGFS
/*
* This can be dangerous especially when we have clients such as
* PMICs, therefore don't provide any real compile time configuration option
--
1.7.0.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/