This is a note to let you know that I've just added the patch titled

serial: 8250_pci: Don't fail on multiport card class

to the 4.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: serial-8250_pci-don-t-fail-on-multiport-card-class.patch and it can be found in the queue-4.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From e7f3e99cb1a667d04d60d02957fbed58b50d4e5a Mon Sep 17 00:00:00 2001

From: Andy Shevchenko andriy.shevchenko@linux.intel.com Date: Fri, 2 Feb 2018 20:39:13 +0200 Subject: serial: 8250_pci: Don't fail on multiport card class

From: Andy Shevchenko andriy.shevchenko@linux.intel.com

commit e7f3e99cb1a667d04d60d02957fbed58b50d4e5a upstream.

Do not fail on multiport cards in serial_pci_is_class_communication().

It restores behaviour for SUNIX multiport cards, that enumerated by class and have a custom board data.

Moreover it allows users to reenumerate port-by-port from user space.

Fixes: 7d8905d06405 ("serial: 8250_pci: Enable device after we check black list") Reported-by: Nikola Ciprich nikola.ciprich@linuxbox.cz Signed-off-by: Andy Shevchenko andriy.shevchenko@linux.intel.com Tested-by: Nikola Ciprich nikola.ciprich@linuxbox.cz Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- drivers/tty/serial/8250/8250_pci.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)

--- a/drivers/tty/serial/8250/8250_pci.c +++ b/drivers/tty/serial/8250/8250_pci.c @@ -3387,11 +3387,9 @@ static int serial_pci_is_class_communica /* * If it is not a communications device or the programming * interface is greater than 6, give up. - * - * (Should we try to make guesses for multiport serial devices - * later?) */ if ((((dev->class >> 8) != PCI_CLASS_COMMUNICATION_SERIAL) && + ((dev->class >> 8) != PCI_CLASS_COMMUNICATION_MULTISERIAL) && ((dev->class >> 8) != PCI_CLASS_COMMUNICATION_MODEM)) || (dev->class & 0xff) > 6) return -ENODEV; @@ -3428,6 +3426,12 @@ serial_pci_guess_board(struct pci_dev *d { int num_iomem, num_port, first_port = -1, i;

+ /* + * Should we try to make guesses for multiport serial devices later? + */ + if ((dev->class >> 8) == PCI_CLASS_COMMUNICATION_MULTISERIAL) + return -ENODEV; + num_iomem = num_port = 0; for (i = 0; i < PCI_NUM_BAR_RESOURCES; i++) { if (pci_resource_flags(dev, i) & IORESOURCE_IO) {

Patches currently in stable-queue which might be from andriy.shevchenko@linux.intel.com are

queue-4.15/serial-8250_pci-don-t-fail-on-multiport-card-class.patch