refactor(usb_host): Removed parent_dev_hdl from device tree node in Hub Driver (part2/4)

[roma-jam]

Description

Removed parent device handle from the device tree node. Device tree node has the void* pointer to the parent (which is NULL when the port is part of the Root Hub, and external hub handle when the port is a part of external hub).
As the device tree node doesn't contain parent information and contain the external hub handle, we don't need to convert usb_device_handle_t to ext_hub_handle_t.
Added the possibility to get the external hub device speed to compare it with the speed of the port.

Related

• Cherry-picked from refactor(usb_host): Move parent-child tree management to Hub Driver #267
• Prerequisites in refactor(usb_host): Removed parent_dev_hdl and parent_port_num from Enum Driver (part1/4) #288
• Follow-up in refactor(usb_host): Removed parent_dev_hdl from the External Port Driver (part3/4) #290
• Relates to IDF-10023 - Move parent-child tree management responsibility to Hub Driver

Testing

USB Host target tests.

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Checklist

Before submitting a Pull Request, please ensure the following:

• 🚨 This PR does not introduce breaking changes.
• All CI checks (GH Actions) pass.
• Documentation is updated as needed.
• Tests are updated or added as necessary.
• Code is well-commented, especially in complex areas.
• Git history is clean — commits are squashed to the minimum necessary.

[igi540]

LGTM. Only one point - in ext_hub_get_speed(), there's a potential race condition around the dev_is_in_list() check and the subsequent dereference of ext_hub_hdl.

Currently, the function exits the critical section after checking p_ext_hub_driver, but before verifying if the hub is still valid and before accessing its dev_hdl. If the hub were removed concurrently (e.g., from another task), this could lead to a use-after-free or undefined behavior.