Claude review: drm/connector: Add HDMI 2.0 scrambler infrastructure

[Claude Code Review Bot <claude-review@example.com>]

Patch Review

The infrastructure additions look reasonable. A few observations:

1. **`INIT_DELAYED_WORK` in `drm_connector_init_only()`**: This initializes `scdc_work` for *all* connectors, not just HDMI ones. While harmless (the work is never scheduled for non-HDMI connectors), it's slightly wasteful. However, this is consistent with how `mutex_init(&connector->hdmi.infoframes.lock)` is already done unconditionally on the adjacent line, so this follows existing pattern.

2. **`scdc_cb` function pointer without locking documentation**: The `scdc_cb` callback pointer is assigned and cleared from `drm_scdc_start_scrambling()`/`drm_scdc_stop_scrambling()`, and read from the work item `drm_connector_hdmi_scdc_work()`. The `scrambler_enabled` flag is protected by `READ_ONCE`/`WRITE_ONCE`, but `scdc_cb` itself has no such annotation. There's a potential race between `drm_scdc_stop_scrambling()` setting `scdc_cb = NULL` after `cancel_delayed_work_sync()`, and the work item checking `scdc_cb`. Since `cancel_delayed_work_sync()` ensures the work item completes before returning, and subsequent scheduling is prevented by `scrambler_enabled` being false, this is actually safe in practice. But a comment explaining the ordering guarantee would be helpful.

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Generated by Claude Code Patch Reviewer