MFD: mcp-core: sanitize host creation/removal

host_unregister() gives us no chance between removing the device
and the mcp data structure being freed to access the data inbetween,
which drivers may need to do if they need to iounmap() pointers in
their private data structures.

Therefore, re-jig the interfaces, which are now, on creation:

	mcp = mcp_host_alloc()
	if (mcp) {
		ret = mcp_host_add(mcp, data);

		if (!ret)
			mcp_host_free(mcp);
	}

and on removal:

	mcp_host_del(mcp);
	... access mcp ...
	mcp_host_free(mcp);

The free does the final put_device() on the struct device as one would
expect.

Acked-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 3 insertions, 2 deletions

diff --git a/include/linux/mfd/mcp.h b/include/linux/mfd/mcp.h
index f88c1cc0cb0f..79a6b13ba20c 100644
--- a/include/linux/mfd/mcp.h
+++ b/include/linux/mfd/mcp.h
@@ -47,8 +47,9 @@ void mcp_disable(struct mcp *);
 #define mcp_get_sclk_rate(mcp)	((mcp)->sclk_rate)
 
 struct mcp *mcp_host_alloc(struct device *, size_t);
-int mcp_host_register(struct mcp *);
-void mcp_host_unregister(struct mcp *);
+int mcp_host_add(struct mcp *);
+void mcp_host_del(struct mcp *);
+void mcp_host_free(struct mcp *);
 
 struct mcp_driver {
 	struct device_driver drv;