serial: 8250_pci: Add support for 16 port Exar boards

Upstream message:

http://www.spinics.net/lists/linux-serial/msg16937.html

Once this patch lands in mainline, we can cherry pick it into the Ubuntu kernel. If you cc the patch to stable it will make it's way into the Ubuntu stable kernel through the normal stable updates.

Thanks Joseph, I will try to get it in stable as well.
-- Soeren

The patch has been merged in 4.1-rc2, but there are two more patch in Greg's tty-testing branch which will be needed as well.
-- Soeren

Finally the patches have been landed in 3.12.y and 3.14.y, so you can pick them from there. Use 3e8c9dd, cfcdadb and 6bfc19b from linux-3.12.y branch. Or 8843ae2, e7a10d9 and 509d000 from linux-3.14.y.

Hi Joseph, do you need anything else to pick the patches?

It looks like these three patches are only needed in Trusty, since they were included in mainline as of 4.1 and 4.2:

96a5d18 serial: 8250_pci: Add support for 16 port Exar boards - v4.1-rc2~17^2
be32c0c serial: 8250_pci: Add support for 12 port Exar boards - v4.2-rc1~87^2~5
899f0c1 serial: 8250_pci: Correct uartclk for xr17v35x expansion chips - v4.2-rc1~87^2~4

I built a trusty test kernel which can be downloaded from:
http://kernel.ubuntu.com/~jsalisbury/lp1447485/

Can you test this kernel and see if it resolves this bug. If it does, I will submit a Trusty SRU request.

Thanks in advance!

Hi Joseph,

I have installed the kernel under 12.04.5 and it works for me, all 16 ports are working. Thank you!

-- Soeren

This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-trusty' to 'verification-done-trusty'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

I can confirm that the changes is working as expected. Tag has been changed

Thanks a lot.
--
Soeren

This bug was fixed in the package linux - 3.13.0-93.140

---------------
linux (3.13.0-93.140) trusty; urgency=low

  [ Seth Forshee ]

  * Release Tracking Bug
    - LP: #1604134

  * Boot failure with EFI stub (LP: #1603476)
    - x86/efi: Fix boot failure with EFI stub

  * CVE-2016-5243 (LP: #1589036)
    - tipc: fix an infoleak in tipc_nl_compat_link_dump

  * qeth: delete napi struct when removing a qeth device (LP: #1601831)
    - qeth: delete napi struct when removing a qeth device

  * deadlock on balloon deflation (LP: #1598197)
    - SAUCE: mm/balloon_compaction: Fix Regression of LP#1572562

  * serial: 8250_pci: Add support for 16 port Exar boards (LP: #1447485)
    - serial: 8250_pci: Add support for 16 port Exar boards
    - serial: 8250_pci: Add support for 12 port Exar boards
    - serial: 8250_pci: Correct uartclk for xr17v35x expansion chips

  * linux: Homogenize changelog format across releases (LP: #1599562)
    - Revert "UBUNTU: [debian] BugLink: close LP: bugs only for Launchpad urls"
    - [Debian] git-ubuntu-log -- switch to bug order
    - [Debian] git-ubuntu-log -- fix empty section formatting
    - [Debian] git-ubuntu-log -- output should be utf-8
    - [Debian] git-ubuntu-log -- handle invalid or private bugs
    - [Debian] git-ubuntu-log -- wrap long bug and commit titles
    - [Debian] git-ubuntu-log -- ensure we get the last commit
    - [Debian] git-ubuntu-log -- prevent bug references being split
    - [Debian] git-ubuntu-log -- git log output is UTF-8

  * exercising ptys causes a kernel oops (LP: #1586418)
    - devpts: fix null pointer dereference on failed memory allocation

  * Miscellaneous upstream changes
    - KEYS: potential uninitialized variable

 -- Seth Forshee <email address hidden> Mon, 18 Jul 2016 15:05:56 -0500