On Mon, Mar 23, 2020 at 07:52:11AM +0100, Greg Kroah-Hartman wrote: > On Sun, Mar 22, 2020 at 03:40:33PM -0400, Ryan Lovelett wrote: > > I have been trying to find a way to get my Adafruit FT232H breakout > > board [1] to appear as a user space GPIO device so I can use it with > > libgpiod. As far as I can tell from reading table 3.5 from the > > datasheet [2] ACBUS5, ACBUS6, ACBUS8 and ACBUS9 should all be usable > > for this. > > > > I found a patch that was submitted by Karoly Pados in 2018 [3] that > > seemes to add support for that (though maybe only for a specific chip). > > > > Through a little bit of ftrace and printk I realized that the switch > > statement in ftdi_gpio_init was falling through to the default case for > > the FT232H [4]. > > So it sounds like you have the wrong device type. Can you make sure you > use the latest kernel release (5.5) and if you have problems with this, > email the linux-usb mailing list as the driver maintainers for that > driver are there. As Greg suggested you need to update your kernel as GPIO support for FT232H went into 5.4. Johan