Hi,
I am trying to port the USBHOST driver to RX65N controller. Basically I am using lpc17_40_usbhost.c as reference (as this contains all the functions of framework (xxxx_usbhost_initialize()) and host controller functions (such as xxxx_wait(), xxxx_enumerate() etc)) in one file itself. Other reference such as imxrt also follows same but the framework related code is in (/boards/.../src/imxrt_usbhost.c:) and host controller related code is in /arch/.../imxrt_ehci.c. I have some basic doubts and your thoughts/ comments/ suggestion would help me. 1. Basically all the references invariably refer to EHCI/ OHCI. But the USB host in RX65N controller which we are using does not mention any thing about this EHCI/ OHCI. My understanding is it should not matter but still - Is there any things specific to be configured with respect to Nuttx for these EHCI/ OHCI? RX65N contains USB peripheral with USB 2.0 complaint and Full Speed. 2. What is IOBUFFERS with respect to USB Host? lpc17_40_usbhost.c refers to LPC17_40_IOBUFFERS (and used as some #define) Is is the USB memory dedicated for USB transfer? Or can we use normal RAM itself? What is the specific use of IOBUFFER and how it needs to be configured? 3. We see xxxx_ioalloc and xxxx_iofree as well as xxxx_alloc and xxxx_free? What is the difference between them? Is it that, xxxx_ioalloc and xxxx_iofree functions are used with IOBUFFER? If we don't want to use them, just implementing xxxx_alloc and xxxx_free is sufficient/ OK? 4. Many places, it is seen the debug code is wrapped between CONFIG_DEBUG_USB_INFO, this depends on CONFIG_DEBUG_USB and I could not find where to enable this option (not sure, if I missed something in KConfig). As I continue, possibly there will some more doubts/ some more clarity :) With best regards, Phani.
