For your issue, this is potentially a bug specific to the 4.5 driver. We used to poll once a second, which would hide legacy irq issues during initialization, but 4.5 removed it. A patch[*] to 4.6 removed all use of legacy interrupts, and should have been applied to 4.5 stable (they were cc'ed on the mailing list).
Kamil,
For your issue, this is potentially a bug specific to the 4.5 driver. We used to poll once a second, which would hide legacy irq issues during initialization, but 4.5 removed it. A patch[*] to 4.6 removed all use of legacy interrupts, and should have been applied to 4.5 stable (they were cc'ed on the mailing list).
* https:/ /git.kernel. org/cgit/ linux/kernel/ git/torvalds/ linux.git/ commit? id=a5229050b69c fffb690b546c357 ca5a60434c0c8