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.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Reported-by: Jonathan Cameron <jic23@jic23.retrosnub.co.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 22ebf00eb56fe77922de8138aa9af9996582c2b3 upstream.

of_address_to_resource return 0 on successful call but
devm_ioremap_resource is called only if it returns non-zero value

Signed-off-by: Lukasz Gemborowski <lukasz.gemborowski@nokia.com>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Reading the register (if allowed) after writing is to ensure writing
is completed on a posted bus. The endianness of reading doesn't matter.

Signed-off-by: York Sun <yorksun@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

With CONFIG_OF=n, the following warnings occur when compiling
drivers/i2c/muxes/i2c-mux-reg.c:

  CC      drivers/i2c/muxes/i2c-mux-reg.o
drivers/i2c/muxes/i2c-mux-reg.c:170:13: warning: ‘struct gpiomux’ declared inside parameter list [enabled by default]
      struct platform_device *pdev)
             ^
drivers/i2c/muxes/i2c-mux-reg.c:170:13: warning: its scope
is only this definition or declaration, which is probably not what you want [enabled by default]
drivers/i2c/muxes/i2c-mux-reg.c: In function ‘i2c_mux_reg_probe’:
drivers/i2c/muxes/i2c-mux-reg.c:201:3: warning: passing argument 1 of ‘i2c_mux_reg_probe_dt’ from incompatible pointer type [enabled by default]
   ret = i2c_mux_reg_probe_dt(mux, pdev);
   ^

Signed-off-by: Mike Rapoport <mike.rapoport@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Checking was done at three different locations, just do it once and
properly at probing time.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Tested-by: York Sun <yorksun@freescale.com>

Every call of of_parse_phandle() increments user count of found device
node, if OF_DYNAMIC is enabled.

The change fixes all similar addressed cases in drivers/i2c.

Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Based on i2c-mux-gpio driver, similarly the register-based mux
switch from one bus to another by setting a single register.
The register can be on PCIe bus, local bus, or any memory-mapped
address. The endianness of such register can be specified in device
tree if used, or in platform data.

Signed-off-by: York Sun <yorksun@freescale.com>
Acked-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

This change is needed to properly lock I2C parent bus driver.

Prior to this change i2c_put_adapter() is misused, which may lead
to an overflow over zero of I2C bus driver user counter.

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c_driver does not need to set an owner because i2c_register_driver()
will set it.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

pca9541 and pca954x are calling master_xfer() of the parent adapter directly
thus bypassing the quirks checks of the adapter. Use __i2c_transfer() instead.

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Tested-by: Łukasz Gemborowski <lukasz.gemborowski@nokia.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
Fixes: b7f625840267b1 ("i2c: add quirk checks to core")