[PATCH next 1/2] drivers/base: Extend documentation with preferred way to use auxbus

[PATCH next 1/2] drivers/base: Extend documentation with preferred way to use auxbus

[Leon Romanovsky]

Document the preferred way to use auxiliary bus.

Signed-off-by: Leon Romanovsky <leon@kernel.org>
---
 drivers/base/auxiliary.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/base/auxiliary.c b/drivers/base/auxiliary.c
index afa4df4c5a3f..248d3508ca0e 100644
--- a/drivers/base/auxiliary.c
+++ b/drivers/base/auxiliary.c
@@ -156,6 +156,16 @@
  *		},
  *		.ops = my_custom_ops,
  *	};
+ *
+ * Please note that such custom ops approach is valid, but it is hard to implement
+ * it right without global locks per-device to protect from auxiliary_drv removal
+ * during call to that ops. In addition, this implementation lacks proper module
+ * dependency, which causes to load/unload races between auxiliary parent and devices
+ * modules.
+ *
+ * The most easiest way to provide these ops reliably whtout need to have lock is
+ * to EXPORT_SYMBOL*() them and rely on already existing modules infrastructure for validity
+ * and correct dependencies chains.
  */
 
 static const struct auxiliary_device_id *auxiliary_match_id(const struct auxiliary_device_id *id,
-- 
2.48.1

[PATCH next 2/2] drivers/base: Add myself as auxiliary bus reviewer

[Leon Romanovsky]

As the one who participated in initial development of auxiliary bus
and later reviewed many of existing auxiliary bus consumers, I would
like to be CCed on all auxiliary bus changes.

Add myself as a reviewer to do not miss new development in that area.

Signed-off-by: Leon Romanovsky <leon@kernel.org>
---
 MAINTAINERS | 1 +
 1 file changed, 1 insertion(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index d5dfb9186962..c284a8d54fad 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3834,6 +3834,7 @@ AUXILIARY BUS DRIVER
 M:	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 R:	Dave Ertman <david.m.ertman@intel.com>
 R:	Ira Weiny <ira.weiny@intel.com>
+R:	Leon Romanovsky <leon@kernel.org>
 S:	Supported
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git
 F:	Documentation/driver-api/auxiliary_bus.rst
-- 
2.48.1