In case of error, the function pinctrl_register() returns
NULL not ERR_PTR(). The IS_ERR() test in the return value
check should be replaced with NULL test.
The function syscon_regmap_lookup_by_phandle() returns ERR_PTR()
and never returns NULL. The NULL test in the return value check
should be replaced with IS_ERR().
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: NSrinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

This patch add pinctrl support to ST SoCs.

About hardware:
ST Set-Top-Box parts have two blocks called PIO and PIO-mux which handle
pin configurations.

Each multi-function pin is controlled, driven and routed through the PIO
multiplexing block. Each pin supports GPIO functionality (ALT0) and
multiple alternate functions(ALT1 - ALTx) that directly connect the pin
to different hardware blocks. When a pin is in GPIO mode, Output Enable
(OE), Open Drain(OD), and Pull Up (PU) are driven by the related PIO
block. Otherwise the PIO multiplexing block configures these parameters
and retiming the signal.

About driver:
This pinctrl driver manages both PIO and PIO-mux block using pinctrl,
pinconf, pinmux, gpio subsystems. All the pinctrl related config
information can only come from device trees.
Signed-off-by: NSrinivas Kandagatla <srinivas.kandagatla@st.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NMark Brown <broonie@linaro.org>