libgpiod ?

[jqz 0]

Hi,

Does anyone uses libgpiod library on TBoard-s?  The command gpioinfo displays the gpiochips and lines that
the library can access and there's a lot of them. In reality there's only a few gpio lines on each gpiochips that are usable if
their respective alternate functions are not already set in the devicetree.
It would be super nice if those usable lines are labeled that correspond to that fancy colour coded  pinout
in the board.

But for now I would like to know which of the lines I could actually use as gpios.
Any pointer or directions where to look for more help would be greatly appreciated.

[jqz 0]

so I managed to add some names to the device tree, but I'm not quite sure if it's correct?
There are 32 lines in gpiochip5 and I'm not sure if GP5B0 is actually at line0.
Surely, If I was able to do something like this, this should be easily done by the experts.

I added this to .dts file

&gpio5 {
	gpio-line-names = 
		"GP5B0",
		"GP5B1",
		"GP5B2",
		"GP5B3",
		"GP5B4",
		"GP5B5",
		"GP5B6",
		"GP5B7",
		"GP5C0",
		"", /* GPIO5C1 */
		"", /* GPIO5C2 */
		"GPIO5C3";
};

This is on a slackwarearm kernel 5.10.
and the result is this:

[diozero 0]

I'm the author of the diozero Java library that is portable across many SBCs and have written a number of utility applications, one of which allows you to display information about the connected board:

> java -cp diozero-sampleapps-1.3.0.jar com.diozero.sampleapps.SystemInformation

Local System Info
Operating System: ubuntu 20.04.2 LTS (Focal Fossa)
I2C buses: [2, 0, 5]
CPU Temperature: 37.27

Native Device Factory: DefaultDeviceFactory
Board: Asus Tinker Board (RAM: 2,048,000 bytes, O/S: ubuntu 20.04.2 LTS (Focal Fossa))

Header: DEFAULT
+-----+----------+--------+----------+--------+----------+-----+
+ GP# +     Name +  gpiod + Physical + gpiod  + Name     + GP# +
+-----+----------+--------+----------+--------+----------+-----+
|     |      3v3 |        |  1 || 2  |        | 5v       |     |
| 252 | GPIO8_A4 |  8:4   |  3 || 4  |        | 5v       |     |
| 253 | GPIO8_A5 |  8:5   |  5 || 6  |        | GND      |     |
|  17 | GPIO0_C1 |  0:17  |  7 || 8  |  5:9   | GPIO5_B1 | 161 |
|     |      GND |        |  9 || 10 |  5:8   | GPIO5_B0 | 160 |
| 164 | GPIO5_B4 |  5:12  | 11 || 12 |  6:0   | GPIO6_A0 | 184 |
| 166 | GPIO5_B6 |  5:14  | 13 || 14 |        | GND      |     |
| 167 | GPIO5_B7 |  5:15  | 15 || 16 |  5:10  | GPIO5_B2 | 162 |
|     |      3v3 |        | 17 || 18 |  5:11  | GPIO5_B3 | 163 |
| 257 | GPIO8_B1 |  8:9   | 19 || 20 |        | GND      |     |
| 256 | GPIO8_B0 |  8:8   | 21 || 22 |  5:19  | GPIO5_C3 | 171 |
| 254 | GPIO8_A6 |  8:6   | 23 || 24 |  8:7   | GPIO8_A7 | 255 |
|     |      GND |        | 25 || 26 |  8:3   | GPIO8_A3 | 251 |
| 233 | GPIO7_C1 |  7:17  | 27 || 28 |  7:18  | GPIO7_C2 | 234 |
| 165 | GPIO5_B5 |  5:13  | 29 || 30 |        | GND      |     |
| 168 | GPIO5_C0 |  5:16  | 31 || 32 |  7:23  | GPIO7_C7 | 239 |
| 238 | GPIO7_C6 |  7:22  | 33 || 34 |        | GND      |     |
| 185 | GPIO6_A1 |  6:1   | 35 || 36 |  7:7   | GPIO7_A7 | 223 |
| 224 | GPIO7_B0 |  7:8   | 37 || 38 |  6:3   | GPIO6_A3 | 187 |
|     |      GND |        | 39 || 40 |  6:4   | GPIO6_A4 | 188 |
+-----+----------+--------+----------+--------+----------+-----+

Plus GpioReadAll:

> java -cp diozero-sampleapps-1.3.0.jar com.diozero.sampleapps.GpioReadAll
Header: DEFAULT
+-----+----------+------+---+--------+----------+--------+---+------+----------+-----+
+ GP# +     Name + Mode + V +  gpiod + Physical + gpiod  + V + Mode + Name     + GP# +
+-----+----------+------+---+--------+----------+--------+---+------+----------+-----+
|     |      3v3 |      |   |        |  1 || 2  |        |   |      | 5v       |     |
| 252 | GPIO8_A4 |   In | 0 |  8:4   |  3 || 4  |        |   |      | 5v       |     |
| 253 | GPIO8_A5 |   In | 0 |  8:5   |  5 || 6  |        |   |      | GND      |     |
|  17 | GPIO0_C1 |   In | 0 |  0:17  |  7 || 8  |  5:9   | 0 | Unkn | GPIO5_B1 | 161 |
|     |      GND |      |   |        |  9 || 10 |  5:8   | 0 | Unkn | GPIO5_B0 | 160 |
| 164 | GPIO5_B4 |   In | 0 |  5:12  | 11 || 12 |  6:0   | 0 | Unkn | GPIO6_A0 | 184 |
| 166 | GPIO5_B6 | Unkn | 0 |  5:14  | 13 || 14 |        |   |      | GND      |     |
| 167 | GPIO5_B7 | Unkn | 0 |  5:15  | 15 || 16 |  5:10  | 0 | In   | GPIO5_B2 | 162 |
|     |      3v3 |      |   |        | 17 || 18 |  5:11  | 0 | In   | GPIO5_B3 | 163 |
| 257 | GPIO8_B1 |   In | 0 |  8:9   | 19 || 20 |        |   |      | GND      |     |
| 256 | GPIO8_B0 |   In | 0 |  8:8   | 21 || 22 |  5:19  | 0 | In   | GPIO5_C3 | 171 |
| 254 | GPIO8_A6 |   In | 0 |  8:6   | 23 || 24 |  8:7   | 0 | In   | GPIO8_A7 | 255 |
|     |      GND |      |   |        | 25 || 26 |  8:3   | 0 | In   | GPIO8_A3 | 251 |
| 233 | GPIO7_C1 |   In | 0 |  7:17  | 27 || 28 |  7:18  | 0 | In   | GPIO7_C2 | 234 |
| 165 | GPIO5_B5 |   In | 0 |  5:13  | 29 || 30 |        |   |      | GND      |     |
| 168 | GPIO5_C0 |   In | 0 |  5:16  | 31 || 32 |  7:23  | 0 | Unkn | GPIO7_C7 | 239 |
| 238 | GPIO7_C6 | Unkn | 0 |  7:22  | 33 || 34 |        |   |      | GND      |     |
| 185 | GPIO6_A1 | Unkn | 0 |  6:1   | 35 || 36 |  7:7   | 0 | Unkn | GPIO7_A7 | 223 |
| 224 | GPIO7_B0 | Unkn | 0 |  7:8   | 37 || 38 |  6:3   | 0 | Unkn | GPIO6_A3 | 187 |
|     |      GND |      |   |        | 39 || 40 |  6:4   | 0 | Unkn | GPIO6_A4 | 188 |
+-----+----------+------+---+--------+----------+--------+---+------+----------+-----+

 

[jqz 0]

Wow thanks!

I'm guessing the column with gpiod is all I need, assuming the numbers
in that column corresponds to  chipnum  :  line number .
I'd also tinker with diozero and see if I could figure out how to use it.

Thanks again.