On Tue, Feb 15, 2022 at 9:36 AM Patrice CHOTARD patrice.chotard@foss.st.com wrote:
Hi Tim
On 2/15/22 17:09, Tim Harvey wrote:
On Tue, Feb 15, 2022 at 5:29 AM Patrice CHOTARD patrice.chotard@foss.st.com wrote:
Hi Tim
On 2/10/22 18:04, Tim Harvey wrote:
Greetings,
I'm trying to understand how to use the U-Boot bind command to bind the usb_ether driver to the usb class to register a USB ethernet gadget network device as referenced in: commit 02291d83fdaaf ("doc: add bind/unbind command documentation") commit 49c752c93a78 ("cmd: Add bind/unbind commands to bind a device to a driver from the command line")
For example, i made some trial on STM32MP1 platform:
At boot, we got :
STM32MP> dm tree Class Index Probed Driver Name
root 0 [ + ] root_driver root_driver firmware 0 [ ] psci |-- psci sysreset 0 [ ] psci-sysreset | `-- psci-sysreset ..... blk 0 [ + ] mmc_blk | | `-- mmc@58005000.blk ethernet 0 [ + ] eth_eqos | |-- ethernet@5800a000 eth_phy_ge 0 [ + ] eth_phy_generic_drv | | `-- ethernet-phy@0 usb 0 [ ] ehci_generic | |-- usb@5800d000 video 0 [ ] stm32_display | |-- display-controller@5a001000 .....
As you can see, there is already an ethernet interface used. We unbind the ethernet interface before binding the usb_ether gadget to the usb class. First unbind the generic ethernet phy (eth_phy_generic_drv) and the ethernet driver (eth_eqos).
STM32MP> unbind eth_phy_generic 0 STM32MP> unbind ethernet 0 STM32MP> dm tree Class Index Probed Driver Name
root 0 [ + ] root_driver root_driver firmware 0 [ ] psci |-- psci sysreset 0 [ ] psci-sysreset | `-- psci-sysreset .... blk 0 [ + ] mmc_blk | | `-- mmc@58005000.blk usb 0 [ ] ehci_generic | |-- usb@5800d000 video 0 [ ] stm32_display | |-- display-controller@5a001000 ....
Ethernet and phy driver are both unbinded. Now we can bind the usb_eher to the usb class
STM32MP> bind usb 0 usb_ether STM32MP> dm tree Class Index Probed Driver Name
root 0 [ + ] root_driver root_driver firmware 0 [ ] psci |-- psci sysreset 0 [ ] psci-sysreset | `-- psci-sysreset .... blk 0 [ + ] mmc_blk | | `-- mmc@58005000.blk usb 0 [ ] ehci_generic | |-- usb@5800d000 ethernet 0 [ ] usb_ether | | `-- usb_ether video 0 [ ] stm32_display | |-- display-controller@5a001000 ....
usb_ether is now binded. As example, if you can then use some ethernet command as dhcp or ping :
STM32MP> dhcp using dwc2-udc, OUT ep2out-bulk IN ep1in-bulk STATUS ep3in-int MAC de:ad:be:ef:00:01 HOST MAC de:ad:be:ef:00:00 RNDIS ready high speed config #2: 2 mA, Ethernet Gadget, using RNDIS USB RNDIS network up! BOOTP broadcast 1
I have enabled: CONFIG_DM_USB=y CONFIG_USB_GADGET=y CONFIG_USB_ETHER=y
In my case i enabled also CONFIG_USB_ETH_RNDIS=y
Patrice,
In my case when I try to bind to usb_ether the device can not be found (as it is never registered in the first place): Ventana > unbind ethernet 0 Ventana > bind usb 0 usb_ether Cannot find device 0 of class usb
weird, because below, in the dm tree output, we can see :
usb 0 [ ] ehci_mx6 | | |-- usb@2184000 usb 1 [ ] ehci_mx6 | | |-- usb@2184200
so it should find a usb class device .....
Patrice,
I added some debugging and found that 'bind usb 0 usb_ether' does the following: bind_by_class_index(class="usb" index=0 drv="usb_ether") uclass_get_by_name(name="usb") uclass_get_by_name_len(name="usb" len=3) ^^^ does a strncmp with name=usb and len=3 so it matches the first driver with a class name starting with 'usb' and in this case matches usb_mass_storage instead of 'usb'
Simon, this behavior comes from commit 4b030177b660 ("dm: core: Allow finding children / uclasses by partial name"). Why would device_find_child_by_name() want to use a substring match? I suppose if there is a valid reason for this such as your commit logs describe then those functions should directly call uclass_get_by_name_len() and uclass_get_by_name() should be doing a full name match correct?
Patrice, if I make uclass_get_by_name match the full string with the below patch then 'bind usb 0 usb_ether' indeed works as planned:
diff --git a/drivers/core/uclass.c b/drivers/core/uclass.c index 2578803b7a4d..33dbca544574 100644 --- a/drivers/core/uclass.c +++ b/drivers/core/uclass.c @@ -196,7 +196,16 @@ enum uclass_id uclass_get_by_name_len(const char *name, int len)
enum uclass_id uclass_get_by_name(const char *name) { - return uclass_get_by_name_len(name, strlen(name)); + int i; + + for (i = 0; i < UCLASS_COUNT; i++) { + struct uclass_driver *uc_drv = lists_uclass_lookup(i); + + if (uc_drv && !strcmp(uc_drv->name, name)) + return i; + } + + return UCLASS_INVALID; }
int dev_get_uclass_index(struct udevice *dev, struct uclass **ucp)
I don't see the need to unbind 'ethernet' as you can select the active network device with 'ethact':
Ventana > net list eth0 : ethernet@2188000 00:d0:12:f3:f2:f5 active Ventana > bind usb 0 usb_ether Ventana > net list eth0 : ethernet@2188000 00:d0:12:f3:f2:f5 active eth1 : usb_ether 00:00:00:00:00:00 Ventana > setenv ethact eth1 Ventana > ping 192.168.1.146 ^^^ but now we run into the issue Heiko discovered where the usb_gadget_register_driver() call from ether.c ends up removing usb and usb_ether and without his hack to return from device-remove if device is usb_ether we hang:
@@ -201,12 +202,16 @@ int device_remove(struct udevice *dev, uint flags) const struct driver *drv; int ret;
+printf("%s %s\n", __func__, dev->name); if (!dev) return -EINVAL;
if (!(dev_get_flags(dev) & DM_FLAG_ACTIVATED)) return 0;
+ if (!strncmp(dev->name, "usb_ether", 8)) + return 0; + /* * If the child returns EKEYREJECTED, continue. It just means that it * didn't match the flags.
Best Regards,
Tim