mfd: stmfx: Remove #ifdef guards for PM related functions

Use the new DEFINE_SIMPLE_DEV_PM_OPS() and pm_sleep_ptr() macros
to handle the .suspend/.resume callbacks.

These macros allow the suspend and resume functions to be automatically
dropped by the compiler when CONFIG_SUSPEND is disabled, without having
to use #ifdef guards.

This has the advantage of always compiling these functions in,
independently of any Kconfig option. Thanks to that, bugs and other
regressions are subsequently easier to catch.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Lee Jones <lee@kernel.org>

mfd: stmfx: Disable IRQ in suspend to avoid spurious interrupt

When STMFX supply is stopped, spurious interrupt can occur. To avoid that,
disable the interrupt in suspend before disabling the regulator and
re-enable it at the end of resume.

Fixes: 06252ade9156 ("mfd: Add ST Multi-Function eXpander (STMFX) core driver")
Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: stmfx: Fix macro definition spelling

Clang warns:

In file included from drivers/mfd/stmfx.c:13:
include/linux/mfd/stmfx.h:7:9: warning: 'MFD_STMFX_H' is used as a
header guard here, followed by #define of a different macro
[-Wheader-guard]

Fixes: 06252ade9156 ("mfd: Add ST Multi-Function eXpander (STMFX) core driver")
Link: https://github.com/ClangBuiltLinux/linux/issues/475
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

mfd: Add ST Multi-Function eXpander (STMFX) core driver

STMicroelectronics Multi-Function eXpander (STMFX) is a slave controller
using I2C for communication with the main MCU. Main features are:
- 16 fast GPIOs individually configurable in input/output
- 8 alternate GPIOs individually configurable in input/output when other
STMFX functions are not used
- Main MCU IDD measurement
- Resistive touchscreen controller

Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>