Add the helper functions stmfx_read_reg() and stmfx_write_reg() to avoid
duplicated code for access to stmfx's register with mask.
Signed-off-by: NPatrick Delaunay <patrick.delaunay@st.com>
Reviewed-by: NPatrice Chotard <patrice.chotard@st.com>

Rename the two function used to change the pin configuration
from stmfx_pinctrl_.. stmfx_conf_... to clarify the function usage.

No functional change.
Signed-off-by: NPatrick Delaunay <patrick.delaunay@st.com>
Reviewed-by: NPatrice Chotard <patrice.chotard@st.com>

Move the functions stmfx_pinctrl_set_pupd and stmfx_pinctrl_set_type;
they can be used by the new ops get_dir_flags and set_dir_flags introduced
by next patch.

No functional change.
Signed-off-by: NPatrick Delaunay <patrick.delaunay@st.com>
Reviewed-by: NPatrice Chotard <patrice.chotard@st.com>

Move this uncommon header out of the common header.
Signed-off-by: NSimon Glass <sjg@chromium.org>

Move this uncommon header out of the common header.
Signed-off-by: NSimon Glass <sjg@chromium.org>

Use int as result of dm_i2c_reg_read to avoid warning with
W=1 (warning: comparison is always false due to limited range
of data type [-Wtype-limits])
Signed-off-by: NPatrick Delaunay <patrick.delaunay@st.com>
Reviewed-by: NPatrice Chotard <patrice.chotard@st.com>

At present dm/device.h includes the linux-compatible features. This
requires including linux/compat.h which in turn includes a lot of headers.
One of these is malloc.h which we thus end up including in every file in
U-Boot. Apart from the inefficiency of this, it is problematic for sandbox
which needs to use the system malloc() in some files.

Move the compatibility features into a separate header file.
Signed-off-by: NSimon Glass <sjg@chromium.org>

Alignment with kernel driver.

According to the following tab (coming from STMFX datasheet), updates
have to done in stmfx_pinctrl_conf_set function:

-"type" has to be set when "bias" is configured as "pull-up or pull-down"
-PIN_CONFIG_DRIVE_PUSH_PULL should only be used when gpio is configured as
 output. There is so no need to check direction.

  DIR | TYPE | PUPD | MFX GPIO configuration
  ----|------|------|---------------------------------------------------
  1   | 1    | 1    | OUTPUT open drain with internal pull-up resistor
  ----|------|------|---------------------------------------------------
  1   | 1    | 0    | OUTPUT open drain with internal pull-down resistor
  ----|------|------|---------------------------------------------------
  1   | 0    | 0/1  | OUTPUT push pull no pull
  ----|------|------|---------------------------------------------------
  0   | 1    | 1    | INPUT with internal pull-up resistor
  ----|------|------|---------------------------------------------------
  0   | 1    | 0    | INPUT with internal pull-down resistor
  ----|------|------|---------------------------------------------------
  0   | 0    | 1    | INPUT floating
  ----|------|------|---------------------------------------------------
  0   | 0    | 0    | analog (GPIO not used, default setting)
Signed-off-by: NPatrick Delaunay <patrick.delaunay@st.com>

This patch adds pinctrl/GPIO driver for STMicroelectronics
Multi-Function eXpander (STMFX) GPIO expander.
STMFX is an I2C slave controller, offering up to 24 GPIOs.
The driver relies on UCLASS_PINCTRL and UCLASS_GPIO.
Signed-off-by: NPatrick Delaunay <patrick.delaunay@st.com>
Signed-off-by: NPatrice Chotard <patrice.chotard@st.com>