diff options
authorBartosz Golaszewski <brgl@bgdev.pl>2017-12-22 18:42:08 +0100
committerMark Brown <broonie@kernel.org>2017-12-27 10:33:24 +0000
commit078711d7f88d33b0adebb402a1bcb2aa89afe68b (patch)
parenta5ba91c380b8bcca21e6166fc71c5e5ac9f0db68 (diff)
regmap: debugfs: document why we don't create the debugfs entries
This is a follow-up to commit a5ba91c380b8 ("regmap: debugfs: emit a debug message when locking is disabled"). I figured that a user may see this message, grep the code, come to this place and he still won't know why we actually disabled debugfs. Add a comment explaining the reason. Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl> Signed-off-by: Mark Brown <broonie@kernel.org>
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c
index ae962b756863..f3266334063e 100644
--- a/drivers/base/regmap/regmap-debugfs.c
+++ b/drivers/base/regmap/regmap-debugfs.c
@@ -529,6 +529,13 @@ void regmap_debugfs_init(struct regmap *map, const char *name)
struct regmap_range_node *range_node;
const char *devname = "dummy";
+ /*
+ * Userspace can initiate reads from the hardware over debugfs.
+ * Normally internal regmap structures and buffers are protected with
+ * a mutex or a spinlock, but if the regmap owner decided to disable
+ * all locking mechanisms, this is no longer the case. For safety:
+ * don't create the debugfs entries if locking is disabled.
+ */
if (map->debugfs_disable) {
dev_dbg(map->dev, "regmap locking disabled - not creating debugfs entries\n");

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