Fix/atcphy pipehandler#503
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At boot the Apple co-processor firmware does not acknowledge the pipehandler lock within the fixed 1ms timeout (PIPEHANDLER_LOCK_ACK_TIMEOUT_US = 1000). The function clears the lock bit and returns an error, leaving the PHY unconfigured for the rest of the session and preventing USB3 and DP alt mode from working. Replace the single poll attempt with a retry loop: up to 10 attempts with a 5-10ms sleep between each, giving the firmware approximately 100ms total to respond. Add an early return if the lock is already held to avoid double-locking. Tested on Apple M1 MacBook Air (J313), Fedora Asahi Remix 44, kernel 6.19.14. Boot with multiport hub connected no longer produces "Pipehandler lock not acked" errors and USB3 enumerates correctly. Signed-off-by: milijan <milijan@users.noreply.github.com>
…N on USB3_DP When DP alt mode is negotiated on hotplug, atcphy_mux_set() can be called while atcphy->pipehandler_up is still true. The existing WARN_ON fired unconditionally, but the situation has two distinct sub-cases that require different handling: 1. Target mode uses ATCPHY_PIPEHANDLER_STATE_DUMMY (DP-only, USB2, TBT, OFF): pipehandler_up being true is a teardown race between the TypeC mux call chain (cd321x_update_work -> typec_mux_set -> atcphy_mux_set) and the DWC3 PHY teardown (phy_power_off -> atcphy_usb3_power_off). By the time the kernel TypeC stack reaches atcphy_mux_set the USB PD Enter_Mode handshake is complete and the SS lanes are already being repurposed, so switching the pipehandler to dummy is safe. Tear it down explicitly here rather than relying on the race resolving itself. 2. Target mode uses ATCPHY_PIPEHANDLER_STATE_USB3 (USB3_DP, pin assignment D): pipehandler_up being true is correct and expected. The Apple USB-C Digital AV Multiport Adapter (05ac:1463) always negotiates pin assignment D, so the previous WARN_ON fired on every hotplug despite nothing being wrong with the pipehandler state. Retain the WARN_ON but scope it to case 1 only: warn when the target mode requires dummy state but the pipehandler is still up after the explicit teardown attempt (indicating atcphy_configure_pipehandler_dummy failed). Do not warn for USB3_DP transitions where USB3 pipehandler state is the correct precondition. Tested on Apple M1 MacBook Air (J313), Fedora Asahi Remix 44, kernel 6.19.14, with Apple USB-C Digital AV Multiport Adapter (05ac:1463). Hotplug no longer produces a spurious WARN_ON. Signed-off-by: milijan <milijan@users.noreply.github.com>
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Two fixes observed on J313 (M1 MacBook Air) with a USB-C multiport hub:
Retry pipehandler lock with backoff: Replace the single poll with up to 10 retries at 5–10 ms intervals (~100 ms total). Avoids having to hard cycle the usb-c connection.
Fix teardown race and spurious WARN on USB3_DP. Scope the WARN to the failure case only.
Tested on Fedora Asahi Remix 44, kernel 6.19.