Patch "i2c: mux: fix up dependencies" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

i2c: mux: fix up dependencies

to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
i2c-mux-fix-up-dependencies.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Linus Walleij <[email protected]>
Date: Mon, 14 Nov 2016 15:34:17 +0100
Subject: i2c: mux: fix up dependencies

From: Linus Walleij <[email protected]>

commit 93d710a65ef02fb7fd48ae207e78f460bd7a6089 upstream.

We get the following build error from UM Linux after adding an entry to drivers/iio/gyro/Kconfig that issues "select I2C_MUX":

ERROR: "devm_ioremap_resource"
[drivers/i2c/muxes/i2c-mux-reg.ko] undefined!
ERROR: "of_address_to_resource"
[drivers/i2c/muxes/i2c-mux-reg.ko] undefined!

It appears that the I2C mux core code depends on HAS_IOMEM for historical reasons, while CONFIG_I2C_MUX_REG does *not* have a direct dependency on HAS_IOMEM.

This creates a situation where a allyesconfig or allmodconfig for UM Linux will select I2C_MUX, and will implicitly enable I2C_MUX_REG as well, and the compilation will fail for the register driver.

Fix this up by making I2C_MUX_REG depend on HAS_IOMEM and removing the dependency from I2C_MUX.

---
 drivers/i2c/Kconfig       |    1 -
 drivers/i2c/muxes/Kconfig |    1 +
 2 files changed, 1 insertion(+), 1 deletion(-)

@@ -59,7 +59,6 @@ config I2C_CHARDEV
 
 config I2C_MUX
 	tristate "I2C bus multiplexing support"
-	depends on HAS_IOMEM
 	help
 	  Say Y here if you want the I2C core to support the ability to
 	  handle multiplexed I2C bus topologies, by presenting each

@@ -63,6 +63,7 @@ config I2C_MUX_PINCTRL
 
 config I2C_MUX_REG
 	tristate "Register-based I2C multiplexer"
+	depends on HAS_IOMEM
 	help
 	  If you say yes to this option, support will be included for a
 	  register based I2C multiplexer. This driver provides access to

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/i2c-mux-fix-up-dependencies.patch