Hi Shimodaさん

From: Yoshihiro Shimoda
Sent: Thursday, November 15, 2018 4:20 AM

quoted

Host does NOT work:
	//else
	//	/* No otg, so default to host mode */
	//	writel(0x00000000, usb2_base + USB2_COMMCTRL);

I got it. However, I have a concern how to set the mode to peripheral on
RZ/A2
if we applied this code. If someone would like to use the USB as
peripheral
on his board, this code is not suitable.

But USB peripheral is a different driver. So, this code will not run. So
USB2_COMMCTRL will keep the default value 0x80000000.

Correct?

So, I have an idea to set the default mode by using "dr_mode" property,
instead of hardcoded. Since the driver already has such a function,
we can reuse rcar_gen3_device_recognition() to set the default value.
To achieve that, we need to modify the following though.
 - Don't enable "is_otg_channel".
 - Don't call rcar_gen3_enable_vbus_ctrl() to avoid ADPCTRL register
   because RZ/A2 doesn't have it.
 - Don't need to call rcar_gen3_set_linectrl to avoid LINECTRL1 register
   because RZ/A2 doesn't seem to need the setting on host mode.

What do you think?

If a board is designed for USB peripheral, why would they enable a EHCI 
host driver for the same USB channel?
I am confused.

quoted

quoted

(In other words, if we use the port as peripheral with the reset value
0x80000000, does it work?)

We have not been able to get USB peripheral working on RZ/A2 yet.
For peripheral, RZ/A2 has HS-USB.
After plugging into the PC, HS-USB goes to Suspended state (DVSQ =

"0110").

quoted

It should go to Configured state (DVSQ = "0011")

I guess we need to modify ./drivers/usb/renesas_usbhs/rza.c for RZ/A2
because RZ/A2's HS-USB has SYSCFG.CNEN, but doesn't have SYSCFG.UPLLE?

Today for RZ/A1, we tell people to use USB0 first in their board design,
then use USB1 if they need a second USB channel. USB pins are dedicated
(no other function) so there should be no design conflicts.

If only USB1 is used, USB0 must also be enabled in DT as a dummy driver 
(so SYSCFG.UPLLE can get set for USB1).

quoted

According to the RZ/A2 Hardware Manual, COMMCTRL should be 0x80000000

when

quoted

using HS-USB.

There are 2 channels of USB on RZ/A2 (host x 2, HS_USB x 2)

I got it. So, I guess someone wants to use 1 host and 1 peripheral :)

Yes.

Chris