On Wed, Jan 12, 2022 at 2:17 AM Michael Walle michael@walle.cc wrote:
Am 2022-01-11 17:52, schrieb Adam Ford:
On Tue, Jan 11, 2022 at 9:31 AM Michael Walle michael@walle.cc wrote:
Hi,
Am 2022-01-11 15:20, schrieb Adam Ford:
On Tue, Jan 4, 2022 at 2:32 AM Michael Walle michael@walle.cc wrote:
The imx8mm and imx8mn appear compatible with imx7d-usb flags in the OTG driver. If the dr_mode is defined as host or peripheral, the device appears to operate correctly, however the auto host/peripheral detection results in an error.
The solution isn't just adding checks for imx8mm and imx8mn to the check for imx7, because the USB clock needs to be running to read from the USBNC_PHY_STATUS_OFFSET register or it will hang.
The init_type in both priv and plat data are the same, so it doesn't make sense to configure the data in the plat data and copy the data to priv when priv can be configured directly. Instead, rename ehci_usb_of_to_plat to ehci_usb_dr_mode and call it from the probe functions after the clocks are enabled, but before the data is required.
With that added, the additional checks for imx8mm and imx8mn will allow reading the register to automatically determine the state (host or device) of the OTG controller.
Signed-off-by: Adam Ford aford173@gmail.com
V2: Rename ehci_usb_of_to_plat to ehci_usb_dr_mode and call it from the probe after the clocks are enabled, but before the data is needed.
diff --git a/drivers/usb/host/ehci-mx6.c b/drivers/usb/host/ehci-mx6.c index 1bd6147c76..f2a34b7f06 100644 --- a/drivers/usb/host/ehci-mx6.c +++ b/drivers/usb/host/ehci-mx6.c
..
@@ -639,10 +639,8 @@ static int mx6_parse_dt_addrs(struct udevice *dev)
static int ehci_usb_probe(struct udevice *dev) {
struct usb_plat *plat = dev_get_plat(dev); struct usb_ehci *ehci = dev_read_addr_ptr(dev); struct ehci_mx6_priv_data *priv = dev_get_priv(dev);enum usb_init_type type = plat->init_type; struct ehci_hccr *hccr; struct ehci_hcor *hcor; int ret;@@ -660,8 +658,6 @@ static int ehci_usb_probe(struct udevice *dev) return ret;
priv->ehci = ehci;
priv->init_type = type;Michael,
I'm not sure this is correct. There is also this: https://elixir.bootlin.com/u-boot/v2022.01-rc4/source/drivers/usb/host/usb-u...
Further down in the code, you should see: priv->phy_type = usb_get_phy_mode(dev_ofnode(dev));
But that is just fetching the mode from the device tree, the usb_setup_ehci_gadget() referenced above, change the mode during runtime by writing the plat->init_type and reprobing the device.
Which won't work anymore. usb_setup_ehci_gadget() is called from usb_gadget_register_driver() in ci_udc.c. The latter is the one used on the imx, right? But I might be wrong. I'm still trying to figure out how this all works together, because I also try to get OTG running on the dwc3 driver. It looks like the ci_udc.c is special here, and I wonder how a transition to UCLASS_USB_GADGET_GENERIC might look like for this driver.
This driver really isn't changing anything, it's just an order of operations.
It doesn't use the plat->init_type at all anymore, no?
From what I could tell, the only thing that plat->init_type did was to set priv->init_type. The priv structure appears to do most of the work.
but plat->init_type seems to change during runtime (by usb_setup_ehci_gadget()) and with this patch applied, it doesn't do that anymore.
Previously there was a separate that was being called to determine the init_type as being either a peripheral or host. If it wasn't explicitly set in the device tree, the helper function would query a register, however, on the imx8mm and imx8mn platforms, the clocks were not running which resulted in a hang. What I've done is simply move the helper function into the probe and have it run after the clocks start. In theory the register values will be the same as they would be with the help function still in place.
Both Tim Harvey and I have tested on an imx8mm and Fabio tested it on an imx7. For me, the peripheral mode worked when the ID pin of the USB-OTG was not grounded. When it was grounded, the system corrected identified it as a host and I was able to mount a USB drive.
Again, I'm missing something here, but the only user of usb_setup_ehci_gadget() is usb/gadget/ci_udc.c.
I can't speak to what those functions do. What are you suggesting that I do differently?
I'd start by seeing if/when usb_setup_ehci_gadget() is called and see if plat->init_type changes. If its not called, is it dead code then?
I commented out the call to usb_setup_ehci_gadget(), and the gadget driver still enumerated. I'll push a V2 to remove it along with some subsequent patches to update the defconfig, so others who want to use/test it don't have to guess what config options are necessary.
Thanks for catching that.
adam
Sorry I just noticed this, while reviewing how this particular driver works, because I still like to find a working OTG driver in u-boot. I don't have any imx boards.
-michael