AM5728: GPIO banks in am5728

how do i know what are pins are being defined by seeing the code i am unable understand the definitions, syntax and values that are used inside the definitions.

for, Example

am335x_evm_audio_pins: am335x_evm_audio_pins {

pinctrl-single,pins = <

0x10c (PIN_INPUT_PULLDOWN | MUX_MODE4) /* mii1_rx_dv.mcasp1_aclkx */

0x110 (PIN_INPUT_PULLDOWN | MUX_MODE4) /* mii1_txd3.mcasp1_fsx */

0x108 (PIN_OUTPUT_PULLDOWN | MUX_MODE4) /* mii1_col.mcasp1_axr2 */

0x144 (PIN_INPUT_PULLDOWN | MUX_MODE4) /* rmii1_ref_clk.mcasp1_axr3 */

>;

};

i would like to now what are the values 0x10c, 0x110, 0x108, 0x144 and

what is the purpose of PULLDOWN( i mean what actually does " PULLDOWN " make effect ..i want it's meaning with respect to effect it is creating like is it for disabling the pin input for a while or enabling the pin)

rav venkat said:

for, Example

am335x_evm_audio_pins: am335x_evm_audio_pins {

pinctrl-single,pins = <

0x10c (PIN_INPUT_PULLDOWN | MUX_MODE4) /* mii1_rx_dv.mcasp1_aclkx */

0x110 (PIN_INPUT_PULLDOWN | MUX_MODE4) /* mii1_txd3.mcasp1_fsx */

0x108 (PIN_OUTPUT_PULLDOWN | MUX_MODE4) /* mii1_col.mcasp1_axr2 */

0x144 (PIN_INPUT_PULLDOWN | MUX_MODE4) /* rmii1_ref_clk.mcasp1_axr3 */

>;

};

i would like to now what are the values 0x10c, 0x110, 0x108, 0x144 and

what is the purpose of PULLDOWN( i mean what actually does " PULLDOWN " make effect ..i want it's meaning with respect to effect it is creating like is it for disabling the pin input for a while or enabling the pin)

This is for AM335x device.

"0x10c (PIN_INPUT_PULLDOWN | MUX_MODE4) /* mii1_rx_dv.mcasp1_aclkx */" - this is register CONF_MII1_RX_DV at address 0x44E1098C (0x44E10000 + 0x800 + 0x10C)

0x44E10000 - control module base addr

0x800 - pinmux registers offset

0x10C - CONF_MII1_RX_DV register offset

This pin is muxed in mode 4, thus mcasp1_aclkx signal is selected on that pin.

For pulldown, this is internal pull down resistor. More info in AM335x docs.

Regarding AM57x pinmux specifics, see below e2e thread:

Regards,
Pavel

Part Number: AM5728

Hai,

i am working with AM5728 GP EVM board. i am looking for using a GPIO pin that is dedicated and not used by any other signal modes. I saw the schematics but, i am unable to find such GPIO pin in schematics. Can you help me to find such a pin which is only having one mode dedicated as GPIO.

Thanks and Regards

Venkatesh R.

Hi Venkatesh,

From what I understand, you are looking for GPIO pin that has only one mode (GPIO), and no other modes available. Something like pin i2c1_scl (ball C20), which has only I2C mode. And you search the same for GPIO.

I made a search in AM572x DM (Table 4-2 Ball Characteristics), but I am not able to find such GPIO only pin.

Regards,
Pavel

If you have no more questions related to the subject, please close/verify/resolve the below thread.

Regards,
Pavel