# Copyright (c) 2020 HAW Hamburg
#
# This file is subject to the terms and conditions of the GNU Lesser
# General Public License v2.1. See the file LICENSE in the top level
# directory for more details.
#

if MODULE_ST77XX

config MODULE_ST7796
    bool "ST7796 display"
    default y if HAVE_ST7796
    help
        ST7796 display controller is used

if MODULE_ST7796

menuconfig ST7796_CUSTOM_CONFIG
    bool "ST7796 Custom Configuration"
    help
        Enable if customized configuration of voltages are needed. Otherwise
        reset default values are used.

if ST7796_CUSTOM_CONFIG

config ST7796_AVDD
    int "AVDD voltage (in millivolts)"
    default 6600
    range 6200 6800
    help
        Configure the AVDD voltage for analog circuits in millivolts.
        Valid values must be in the range of 6200 (6.2V) to 6800 (6.8V)
        in steps of 200.

config ST7796_AVCL
    int "AVDD voltage (in millivolts)"
    default -4400
    range -5000 -4400
    help
        Configure the AVCL voltage in millivolts.
        Valid values must be in the range of -5000 (-5V) to -4400 (-4.4V)
        in steps of 200.

config ST7796_VCOM
    int "VCOM voltage (in millivolts)"
    default 1000
    range 300 1875
    help
        Configure the VCOM voltage level. VCOM needs to be adjusted to match
        the capacitance and performance specifications of the TFT panel to
        maximize contrast and minimize flickering. VCOM is used to derive the
        GVDD (gamma reference positive voltage) and the GVCL (gamma reference
        negative voltage) as follows:

            GDDV = +VRH + VCOM + VCOM_OFFSET
            GVCL = -VRH + VCOM + VCOM_OFFSET

        Valid values must be in the range of 300 (0.3V) to 1875 (1.875V)
        in steps of 25.

config ST7796_VCOM_OFFSET
    int "VCOM voltage offset (in millivolts)"
    default 0
    range -800 775
    help
        Configure the VCOM voltage offset (VCOM_OFFSET). VCOM_OFFSET is used to
        derive the GVDD (gamma reference positive voltage) and the GVCL (gamma
        reference negative voltage) as follows:

            GDDV = +VRH + VCOM + VCOM_OFFSET
            GVCL = -VRH + VCOM + VCOM_OFFSET

        Valid values must be in the range of -800 (-0.8V) to 775 (0.775V)
        in steps of 25.

config ST7796_VRH
    int "VRH voltage range (in millivolts)"
    default 4500
    range 3550 5500
    help
        Configure the VRH voltage range. VRH is used to derive the GVDD (gamma
        reference positive voltage) and the GVCL (gamma reference negative
        voltage) as follows:

            GDDV = +VRH + VCOM + VCOM_OFFSET + (0.5 * VDV)
            GVCL = -VRH + VCOM + VCOM_OFFSET - (0.5 * VDV)

        Valid values must be in the range of 3350 (3.35V) to 5500 (5.5V)
        in steps of 50.

# TODO  ST7796_VGH and ST7796_VGL (non linear values)

endif # ST7796_CUSTOM_CONFIG
endif # MODULE_ST7796
endif # MODULE_ST77XX