topic How to calculate linux, keymap for 3x2 keypad. in i.MX Processors

How to calculate linux, keymap for 3x2 keypad.

purvi_billore1 — Thu, 26 Sep 2019 09:53:30 GMT

Hello,

I have to use 3x2 keypad for my iMX6 custom board;

where the interfacing with rows are like:

KEY_ROW0

KEY_ROW2

and where the interfacing with columns are like:

KEY_COL0

KEY_COL2

KEY_COL4

Can, anyone guide me to calculate linux, keymap to be added in my device tree:

&kpp {
            compatible = "fsl,imx6q-kpp", "fsl,imx21-kpp";
            clocks = <&clks IMX6QDL_CLK_IPG>;
            pinctrl-0 = <&pinctrl_kpp>;
            linux,keymap = < ?             //KEY_UP

? //KEY_DOWN

? //KEY_LEFT

? //KEY_RIGHT

? //KEY_ESC

? //KEY_ENTER

                                        >;
            keypad,num-rows = <2>;
            keypad,num-columns = <3>;

};

pinctrl_kpp:kpp_grp_1{
              fsl,pins = <
                           MX6QDL_PAD_KEY_COL0__KEY_COL0 0x80000000
                           MX6QDL_PAD_KEY_ROW0__KEY_ROW0 0x80000000
                           MX6QDL_PAD_KEY_COL2__KEY_COL2 0x80000000
                           MX6QDL_PAD_KEY_ROW2__KEY_ROW2 0x80000000
                           MX6QDL_PAD_KEY_COL4__KEY_COL4 0x80000000
>;
};

Re: How to calculate linux, keymap for 3x2 keypad.

igorpadykov — Fri, 27 Sep 2019 00:14:28 GMT

Hi Purvi

one can look at keypad tutorial

4x4 Matrix keypad Interfacing with i-MX6 - Toradex Community

https://community.nxp.com/thread/394434

Best regards
igor
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Re: How to calculate linux, keymap for 3x2 keypad.

purvi_billore1 — Sat, 28 Sep 2019 05:44:01 GMT

Hello,

I have updated my dtsi file as below:

&kpp {
            compatible = "fsl,imx6q-kpp", "fsl,imx21-kpp";
            clocks = <&clks IMX6QDL_CLK_IPG>;
            pinctrl-0 = <&pinctrl_kpp>;
            linux,keymap = <

                                          MATRIX_KEY(0x0, 0x0, KEY_U) //ROW0 COL0 UP
                                          MATRIX_KEY(0x0, 0x2, KEY_D) //ROW0 COL2 DOWN
                                          MATRIX_KEY(0x0, 0x4, KEY_E) //ROW0 COL4 ENTER
                                          MATRIX_KEY(0x2, 0x0, KEY_C) //ROW2 COL0 ESC
                                          MATRIX_KEY(0x2, 0x2, KEY_R) //ROW2 COL2 RIGHT
                                          MATRIX_KEY(0x2, 0x4, KEY_L) //ROW2 COL4 LEFT

                                        >;
            keypad,num-rows = <2>;
            keypad,num-columns = <3>;

};

Now, driver is throwing an error:

"too many keys pressed, control pins initialisation\n"

Re: How to calculate linux, keymap for 3x2 keypad.

purvi_billore1 — Sat, 28 Sep 2019 06:22:18 GMT

Hello,
I have updated my dtsi file as below:
&kpp {
compatible = "fsl,imx6q-kpp", "fsl,imx21-kpp";
clocks = <&clks IMX6QDL_CLK_IPG>;
pinctrl-0 = <&pinctrl_kpp>;
linux,keymap = < MATRIX_KEY(0x0, 0x0, KEY_U) //ROW0 COL0 UP
MATRIX_KEY(0x0, 0x2, KEY_D) //ROW0 COL2 DOWN
MATRIX_KEY(0x0, 0x4, KEY_E) //ROW0 COL4 ENTER
MATRIX_KEY(0x2, 0x0, KEY_C) //ROW2 COL0 ESC
MATRIX_KEY(0x2, 0x2, KEY_R) //ROW2 COL2 RIGHT
MATRIX_KEY(0x2, 0x4, KEY_L) //ROW2 COL4 LEFT
>;
keypad,num-rows = <2>;
keypad,num-columns = <3>;

};

Now, keypad driver is throwing an error:
"too many keys pressed, control pins initialisation"
What more I have to update!!

Re: How to calculate linux, keymap for 3x2 keypad.

igorpadykov — Sun, 29 Sep 2019 22:44:57 GMT

Hi Purvi

one can look at similar error on
iMX7D Matrix Keypad "to many keys pressed" error - Toradex Community

Best regards
igor