Beagleboard:BeagleBone cape interface spec
This is a list of symlink interfaces based on BeagleBone Cape header pins.[1][2][3]
Contents
LEDs
LED | Header pin | BBBWL/BBB | BBAI |
---|---|---|---|
/sys/class/leds/led_P8_03 | P8_03 | gpio1_6 | gpio1_24 |
/sys/class/leds/led_P8_04 | P8_04 | gpio1_7 | gpio1_25 |
/sys/class/leds/led_P8_05 | P8_05 | gpio1_2 | gpio7_1 |
/sys/class/leds/led_P8_06 | P8_06 | gpio1_3 | gpio7_2 |
/sys/class/leds/led_P8_07 | P8_07 | gpio2_2 | gpio6_5 |
/sys/class/leds/led_P8_08 | P8_08 | gpio2_3 | gpio6_6 |
/sys/class/leds/led_P8_09 | P8_09 | gpio2_5 | gpio6_18 |
/sys/class/leds/led_P8_10 | P8_10 | gpio2_4 | gpio6_4 |
/sys/class/leds/led_P8_11 | P8_11 | gpio1_13 | gpio3_11 |
/sys/class/leds/led_P8_12 | P8_12 | gpio1_12 | gpio3_10 |
/sys/class/leds/led_P8_13 | P8_13 | gpio0_23 | gpio4_11 |
/sys/class/leds/led_P8_14 | P8_14 | gpio0_26 | gpio4_13 |
/sys/class/leds/led_P8_15 | P8_15 | gpio1_15 | gpio4_3 |
/sys/class/leds/led_P8_16 | P8_16 | gpio1_14 | gpio4_29 |
/sys/class/leds/led_P8_17 | P8_17 | gpio0_27 | gpio8_18 |
/sys/class/leds/led_P8_18 | P8_18 | gpio2_1 | gpio4_9 |
/sys/class/leds/led_P8_19 | P8_19 | gpio0_22 | gpio4_10 |
/sys/class/leds/led_P8_20 | P8_20 | gpio1_31 | gpio6_30 |
/sys/class/leds/led_P8_21 | P8_21 | gpio1_30 | gpio6_29 |
/sys/class/leds/led_P8_22 | P8_22 | gpio1_5 | gpio1_23 |
/sys/class/leds/led_P8_23 | P8_23 | gpio1_4 | gpio1_22 |
/sys/class/leds/led_P8_24 | P8_24 | gpio1_1 | gpio7_0 |
/sys/class/leds/led_P8_25 | P8_25 | gpio1_0 | gpio6_31 |
/sys/class/leds/led_P8_26 | P8_26 | gpio1_29 | gpio4_28 |
/sys/class/leds/led_P8_27 | P8_27 | gpio2_22 | gpio4_23 |
/sys/class/leds/led_P8_28 | P8_28 | gpio2_24 | gpio4_19 |
/sys/class/leds/led_P8_29 | P8_29 | gpio2_23 | gpio4_22 |
/sys/class/leds/led_P8_30 | P8_30 | gpio2_25 | gpio4_20 |
/sys/class/leds/led_P8_31 | P8_31 | gpio0_10 | gpio8_14 |
/sys/class/leds/led_P8_32 | P8_32 | gpio0_11 | gpio8_15 |
/sys/class/leds/led_P8_33 | P8_33 | gpio0_9 | gpio8_13 |
/sys/class/leds/led_P8_34 | P8_34 | gpio2_17 | gpio8_11 |
/sys/class/leds/led_P8_35 | P8_35 | gpio0_8 | gpio8_12 |
/sys/class/leds/led_P8_36 | P8_36 | gpio2_16 | gpio8_10 |
/sys/class/leds/led_P8_37 | P8_37 | gpio2_14 | gpio8_8 |
/sys/class/leds/led_P8_38 | P8_38 | gpio2_15 | gpio8_9 |
/sys/class/leds/led_P8_39 | P8_39 | gpio2_12 | gpio8_6 |
/sys/class/leds/led_P8_40 | P8_40 | gpio2_13 | gpio8_7 |
/sys/class/leds/led_P8_41 | P8_41 | gpio2_10 | gpio8_4 |
/sys/class/leds/led_P8_42 | P8_42 | gpio2_11 | gpio8_5 |
/sys/class/leds/led_P8_43 | P8_43 | gpio2_8 | gpio8_2 |
/sys/class/leds/led_P8_44 | P8_44 | gpio2_9 | gpio8_3 |
/sys/class/leds/led_P8_45 | P8_45 | gpio2_6 | gpio8_0 |
/sys/class/leds/led_P8_46 | P8_46 | gpio2_7 | gpio8_1 |
/sys/class/leds/led_P9_11 | P9_11 | gpio0_30 | gpio8_17 |
/sys/class/leds/led_P9_12 | P9_12 | gpio1_28 | gpio5_0 |
/sys/class/leds/led_P9_13 | P9_13 | gpio0_31 | gpio6_12 |
/sys/class/leds/led_P9_14 | P9_14 | gpio1_18 | gpio4_25 |
/sys/class/leds/led_P9_15 | P9_15 | gpio1_16 | gpio3_12 |
/sys/class/leds/led_P9_16 | P9_16 | gpio1_19 | gpio4_26 |
/sys/class/leds/led_P9_17 | P9_17 | gpio0_5 | gpio7_17 |
/sys/class/leds/led_P9_18 | P9_18 | gpio0_4 | gpio7_16 |
/sys/class/leds/led_P9_19 | P9_19 | gpio0_13 | gpio7_3 |
/sys/class/leds/led_P9_20 | P9_20 | gpio0_12 | gpio7_4 |
/sys/class/leds/led_P9_21 | P9_21 | gpio0_3 | gpio3_3 |
/sys/class/leds/led_P9_22 | P9_22 | gpio0_2 | gpio6_19 |
/sys/class/leds/led_P9_23 | P9_23 | gpio1_17 | gpio7_11 |
/sys/class/leds/led_P9_24 | P9_24 | gpio0_15 | gpio6_15 |
/sys/class/leds/led_P9_25 | P9_25 | gpio3_21 | gpio6_17 |
/sys/class/leds/led_P9_26 | P9_26 | gpio0_14 | gpio6_14 |
/sys/class/leds/led_P9_27 | P9_27 | gpio3_19 | gpio4_15 |
/sys/class/leds/led_P9_28 | P9_28 | gpio3_17 | gpio4_17 |
/sys/class/leds/led_P9_29 | P9_29 | gpio3_15 | gpio5_11 |
/sys/class/leds/led_P9_30 | P9_30 | gpio3_16 | gpio5_12 |
/sys/class/leds/led_P9_31 | P9_31 | gpio3_14 | gpio5_10 |
/sys/class/leds/led_P9_41 | P9_41 | gpio0_20 | gpio6_20 |
/sys/class/leds/led_P9_91 | P9_91 | gpio3_20 | ❌ |
/sys/class/leds/led_P9_42 | P9_42 | gpio0_7 | gpio4_18 |
/sys/class/leds/led_P9_92 | P9_92 | gpio3_18 | ❌ |
/sys/class/leds/led_A15 | A15 | gpio0_19 | ❌ |
I2C
Bone bus | BBBWL/BBB | BBAI | SCL | SDA | Overlay |
---|---|---|---|---|---|
/dev/bone/i2c/0 | I2C0 | I2C1 | ❌ (On-board) | ||
/dev/bone/i2c/1 | I2C1 | I2C5 | P9.17 | P9.18 | BONE-I2C1.dts |
/dev/bone/i2c/2 | I2C2 | I2C4 | P9.19 | P9.20 | BONE-I2C2.dts |
/dev/bone/i2c/2a | I2C2 | N/A | P9.21 | P9.22 | BONE-I2C2A.dts |
/dev/bone/i2c/3 | I2C1 | I2C3 | P9.24 | P9.26 | BONE-I2C3.dts |
SPI
Bone bus | BBBWL/BBB | BBAI | MOSI | MISO | CLK | CS | Overlay |
---|---|---|---|---|---|---|---|
/dev/bone/spi/0.x | SPI0 | SPI2 | P9.18 | P9.21 | P9.22 | P9.17 (CS0) | BONE-SPI0_0.dts |
/dev/bone/spi/1.x | SPI1 | SPI3 | P9.30 | P9.29 | P9.31 |
|
UART
Bone bus | BBBWL/BBB | BBAI | TX | RX | RTSn | CTSn | Overlays |
---|---|---|---|---|---|---|---|
/dev/bone/uart/0 | UART0 | UART1 | ❌ (console debug header pins) | ||||
/dev/bone/uart/1 | UART1 | UART10 | P9.24 | P9.26 |
|
|
BONE-UART1.dts |
/dev/bone/uart/2 | UART2 | UART3 | P9.21 | P9.22 |
|
|
BONE-UART2.dts |
/dev/bone/uart/3 | UART3 | ❌ | P9.42 | ❌ | ❌ | ❌ | BONE-UART3.dts |
/dev/bone/uart/4 | UART4 | UART5 | P9.13 | P9.11 |
|
|
BONE-UART4.dts |
/dev/bone/uart/5 | UART5 | UART8 | P8.37 | P8.38 | P8.32 | P8.31 | BONE-UART5.dts |
CAN
Bone bus | BBBWL/BBB | BBAI | TX | RX | Overlays |
---|---|---|---|---|---|
/dev/bone/can/0 | CAN0 | ❌ | P9.20 | P9.19 | BONE-CAN0.dts |
/dev/bone/can/1 | CAN1 | CAN2 | P9.26 | P9.24 | BONE-CAN1.dts |
/dev/bone/can/2 | ❌ | CAN1 (rev A2 and later) | P8.8 | P8.7 | TODO |
ADC
Work needs to be done to create these symlinks as well as handle major differences in the driver used for the ADC. Maybe just have the "okay" in here and more in the base tree?
/dev/bone/adc/n
https://github.com/beagleboard/bb.org-overlays/blob/master/src/arm/BB-ADC-00A0.dts
- 0 - AM3358 in_voltage0_raw, AM5729 in_voltage0_raw
- 1 - AM3358 in_voltage1_raw, AM5729 in_voltage1_raw
- 2 - AM3358 in_voltage2_raw, AM5729 in_voltage3_raw
- 3 - AM3358 in_voltage3_raw, AM5729 in_voltage2_raw
- 4 - AM3358 in_voltage4_raw, AM5729 in_voltage7_raw
- 5 - AM3358 in_voltage5_raw, AM5729 in_voltage6_raw
- 6 - AM3358 in_voltage6_raw, AM5729 in_voltage4_raw
PWM
Bone bus | BBBWL/BBB | BBAI | A | B | Overlay |
---|---|---|---|---|---|
/dev/bone/pwm/0 | PWM0 | ❌ | P9.22 | P9.21 | BONE-PWM0.dts |
/dev/bone/pwm/1 | PWM1 | PWM3 | P9.14 | P9.16 | BONE-PWM1.dts |
/dev/bone/pwm/2 | PWM2 | PWM2 | P8.19 | P8.13 | BONE-PWM2.dts |
TIMER PWM
Bone bus | Header pin | BBBWL/BBB | BBAI | overlay |
---|---|---|---|---|
/sys/bus/platform/devices/bone_timer_pwm_0/ | P8.10 | timer6 | timer10 | BONE-TIMER_PWM_0.dts |
/sys/bus/platform/devices/bone_timer_pwm_1/ | P8.07 | timer4 | timer11 | BONE-TIMER_PWM_1.dts |
/sys/bus/platform/devices/bone_timer_pwm_2/ | P8.08 | timer7 | timer12 | BONE-TIMER_PWM_2.dts |
/sys/bus/platform/devices/bone_timer_pwm_3/ | P9.21 | ❌ | timer13 | BONE-TIMER_PWM_3.dts |
/sys/bus/platform/devices/bone_timer_pwm_4/ | P8.09 | timer5 | timer14 | BONE-TIMER_PWM_4.dts |
/sys/bus/platform/devices/bone_timer_pwm_5/ | P9.22 | ❌ | timer15 | BONE-TIMER_PWM_5.dts |
ECAP
/dev/bone/ecap/1
TODO
AM3358 N/A
AM5729 eCAP1_in_PWM1_out
- P8.15
/dev/bone/ecap/2
TODO
AM3358 N/A
AM5729 eCAP2_in_PWM2_out
- P8.14
/dev/bone/ecap/3
TODO
AM3358 N/A
AM5729 eCAP3_in_PWM3_out
- P8.04
MMC
/dev/bone/mmc/2
TODO: need overlay. Note: On Black, this is used by the on-board eMMC. On AI, these pins are available.
AM3358 MMC2
AM5729 MMC3
- P8.21 - CLK
- P8.20 - CMD
- P8.25 - DAT0
- P8.24 - DAT1
- P8.5 - DAT2
- P8.6 - DAT3
- P8.23 - DAT4
- P8.22 - DAT5
- P8.4 - DAT7
- P8.3 - DAT6
LCD
TODO
eQEP
/dev/bone/eqep/0
https://github.com/beagleboard/bb.org-overlays/blob/master/src/arm/bone_eqep0-00A0.dts
AM3358 eQEP0
AM5729 eQEP3
- P9.42 - A
- P9.27 - B
- P9.25 - STROBE (N/A on AI)
- P9.41 - INDEX (N/A on AI)
- P8.6 - STROBE (N/A on AM3358)
- P8.5 - INDEX (N/A on AM3358)
/dev/bone/eqep/1
https://github.com/beagleboard/bb.org-overlays/blob/master/src/arm/bone_eqep1-00A0.dts
AM3358 eQEP1
AM5729 eQEP1
- P8.34 - A
- P8.36 - B
- P9.21 - STROBE (N/A on AM3358)
/dev/bone/eqep/2
https://github.com/beagleboard/bb.org-overlays/blob/master/src/arm/bone_eqep2b-00A0.dts
AM3358 eQEP2
AM5729 eQEP2
- P8.12 - A
- P8.11 - B
- P8.15 - STROBE on AM3358 only
- P8.18 - STROBE on AM5729 only
- P8.16 - INDEX on AM3358 only
- P9.15 - INDEX on AM5729 only
/dev/bone/eqep/2a
https://github.com/beagleboard/bb.org-overlays/blob/master/src/arm/bone_eqep2-00A0.dts
AM3358 eQEP2
AM5729 N/A'
- P8.41 - A
- P8.42 - B
- P8.40 - STROBE
- P8.39 - INDEX
McASP
TODO
PRU
The overlay situation for PRUs is a bit more complex than with other peripherals. The mechanism for loading, starting and stopping the PRUs can go through either UIO or RemoteProc.[4]
/dev/bone/pru/0.0 (eCAP)
Not sure where to put this as it doesn't really have it's own Linux control interface, just an overlay.
TODO: provide overlay, since it is a different pinctrl mode.
AM3358 PRUSS
AM5729 PRUSS1
- P8.15
/dev/bone/pru/0.0
TODO
AM3358 PRU0
AM5729 PRUSS1, PRU0
PIN | AM3358 | AM5729 |
---|---|---|
P8.11 | out 15 | I/O 4 |
P8.12 | out 14 | I/O 3 |
P8.15 | in 15 | see pru/0.1 |
P8.16 | in 16 | see pru/0.1 |
P8.17 | - | I/O 15 |
P9.15 | - | I/O 5 |
P9.24 | in 16 | - |
P9.25 | I/O 7 | see pru/1.1 |
P9.26 | see pru0.1 | I/O 17 |
P9.27 | I/O 5 | see pru/0.1 |
P9.28 | I/O 3 | see pru/1.1 |
P9.29 | I/O 1 | see pru/1.1 |
P9.30 | I/O 2 | see pru/1.1 |
P9.31 | I/O 0 | see pru/1.1 |
P9.41 | I/O 6 | see pru/0.1 |
P9.42 | I/O 4 | see pru/1.1 or pru/2.0 |
USR0 | - | I/O 10 |
USR2 | - | I/O 8 |
USR3 | - | I/O 7 |
USR4 | - | I/O 0 |
/dev/bone/pru/0.1
TODO
AM3358 PRU1
AM5279 PRUSS1, PRU1
PIN | AM3358 | AM5729 |
---|---|---|
P8.13 | - | I/O 7 |
P8.14 | - | I/O 9 |
P8.15 | - | I/O 16 |
P8.16 | - | I/O 18 |
/dev/bone/pru/1.0
TODO
AM3358 N/A
AM5729 PRUSS2, PRU0
- P8.3 - I/O 10 (N/A on AM3358)
- P8.4 - I/O 11 (N/A on AM3358)
- P8.5 - I/O 5 (N/A on AM3358)
- P8.6 - I/O 7 (N/A on AM3358)
- P8.8 - I/O 20 (N/A on AM3358)
/dev/bone/pru/1.1
TODO
AM3358 N/A
AM5729 PRUSS2, PRU1
- P8.7 - I/O 16 (N/A on AM3358)
- P8.9 - I/O 6 (N/A on AM3358)
- P8.10 - I/O 15 (N/A on AM3358)
GPIO
TODO
For each of the pins with a GPIO, there should be a symlink that comes from the names
Methodology
The methodology for applied in the kernel and software images to expose the software interfaces is to be documented here. The most fundamental elements are the device tree entries, including overlays, and udev rules.
Device Trees
udev rules [5]
10-of-symlink.rules[6]
#From: https://github.com/mvduin/py-uio/blob/master/etc/udev/rules.d/10-of-symlink.rules # allow declaring a symlink for a device in DT ATTR{device/of_node/symlink}!="", \ ENV{OF_SYMLINK}="%s{device/of_node/symlink}" ENV{OF_SYMLINK}!="", ENV{DEVNAME}!="", \ SYMLINK+="%E{OF_SYMLINK}", \ TAG+="systemd", ENV{SYSTEMD_ALIAS}+="/dev/%E{OF_SYMLINK}"
TBD
#Also courtesy of mvduin # create symlinks for gpios exported to sysfs by DT SUBSYSTEM=="gpio", ACTION=="add", TEST=="value", ATTR{label}!="sysfs", \ RUN+="/bin/mkdir -p /dev/bone/gpio", \ RUN+="/bin/ln -sT '/sys/class/gpio/%k' /dev/bone/gpio/%s{label}"
Verification
TODO: The steps used to verify all of these configurations is to be documented here. It will serve to document what has been tested, how to reproduce the configurations, and how to verify each major triannual release. All faults will be documented in the issue tracker.