GPIO doesn't work under RaspberryPi-OS Bookworm,

[jk-advedes]

Dear Michael,
while HID to i2c still works fine, GPIO stopped to work. Outcome of "gpioinfo":
gpiochip2 - 14 lines:
line 0: unnamed unused input active-high
line 1: unnamed unused input active-high
line 2: unnamed unused input active-high
line 3: unnamed unused input active-high
line 4: unnamed unused input active-high
line 5: unnamed unused input active-high
line 6: unnamed unused input active-high
line 7: unnamed unused input active-high
line 8: unnamed unused input active-high
line 9: unnamed unused input active-high
line 10: unnamed unused input active-high
line 11: unnamed unused input active-high
line 12: unnamed unused input active-high
line 13: unnamed unused input active-high

As well, shell commands from example on github page stopped to work:
$ ~/hid-ft260 $ cat $SYSFS_FT260/gpio2_func
cat: /gpio2_func: No such file or directory

Confirmation that kernel module is correctly loaded:
$ i2cdetect -l
i2c-20 i2c fef04500.i2c I2C adapter
i2c-21 i2c fef09500.i2c I2C adapter
i2c-22 i2c FT260 usb-i2c bridge I2C adapter

Would you be so kind and test yourself to confirm please? Thanks in advance!

[MichaelZaidman]

Hi @jk-advedes,
thanks for reporting the issue.

1. Please provide the instructions on how to reproduce it.
2. Please share the echo $SYSFS_FT260 output.
3. Please share the entire sudo i2cdetect -l output incorporating all i2c and SMBus adapters.

[jk-advedes]

Hello Michael, many thanks for your interest in the issue! Answers per each question:
1)
tested on: RPI4
$ uname -a
Linux rpi4 6.1.0-rpi8-rpi-v8 #1 SMP PREEMPT Debian 1:6.1.73-1+rpt1 (2024-01-25) aarch64 GNU/Linux
$ git show
commit 4bbf042
$ make V=1
make -C /lib/modules/6.1.0-rpi8-rpi-v8/build M=/home/jura/hid-ft260 modules
make[1]: Entering directory '/usr/src/linux-headers-6.1.0-rpi8-rpi-v8'
make -f /usr/src/linux-headers-6.1.0-rpi8-common-rpi/scripts/Makefile.build obj=/home/jura/hid-ft260 need-builtin=1 need-modorder=1
gcc-12 -Wp,-MMD

$ SYSFS_FT260=$(d=$(ls /sys/bus/hid/drivers/ft260 | grep '0403:6030'); echo /sys/bus/hid/drivers/ft260/$d)
$ echo $SYSFS_FT260
/sys/bus/hid/drivers/ft260/0003:0403:6030.0001 0003:0403:6030.0002
$ ls $SYSFS_FT260
ls: cannot access '0003:0403:6030.0002': No such file or directory
'/sys/bus/hid/drivers/ft260/0003:0403:6030.0001':
chip_mode gpio gpiog_func i2c_reset pwren_status uart_mode
clock gpio2_func hid_over_i2c_en modalias report_descriptor uevent
clock_ctl gpioa_func i2c-22 power subsystem
driver gpiochip2 i2c_enable power_saving_en suspend_status
$ ls /sys/bus/hid/drivers/ft260/0003:0403:6030.0002
driver modalias power report_descriptor subsystem uevent

$ i2cdetect -l
i2c-20 i2c fef04500.i2c I2C adapter
i2c-21 i2c fef09500.i2c I2C adapter
i2c-22 i2c FT260 usb-i2c bridge I2C adapter

Note: FT260 is pin-strapped DCNP0 = high, DCNF1 = low (see datasheet section 5.1 Device Interface Configuration).

[MichaelZaidman]

Hi @jk-advedes,

I see, the SYSFS_FT260 variable is broken. Please try the SYSFS_FT260=/sys/bus/hid/drivers/ft260/0003:0403:6030.0001 command, and then, you should be able to access the ft260 sysfs attributes like cat $SYSFS_FT260/gpio2_func

Please let me know if it works for you.

You should check your DCNF0, and DCNF1 pins configuration because it looks like both USB interfaces are enabled. You can check it by cat $SYSFS_FT260/chip_mode

[MichaelZaidman]

While HID to i2c still works fine, GPIO stopped working.

The gpio works fine. The issue was with the sysfs pass discovered by the helper script from README. It sets the environment variable correctly with a single interface but not when both are enabled. Since FT260 is a USB device, it appears under different sysfs paths on other systems. So, the user is expected to figure out the correct path by himself. To simplify this task, I provided the oneliner bash script, assuming only a single i2c interface is enabled since the driver in the main branch does not support the second interface yet. Nevertheless, I added the setenv.sh script supporting multiple interfaces and FT260 devices, and updated the README with the example. Please try. I would appreciate your feedback.