This is a note to let you know that I've just added the patch titled serial: 8250_pci: Enumerate Elkhart Lake UARTs via dedicated driver to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: serial-8250_pci-enumerate-elkhart-lake-uarts-via-dedicated-driver.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 7f0909db761535aefafa77031062603a71557267 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> Date: Tue, 13 Jul 2021 13:17:39 +0300 Subject: serial: 8250_pci: Enumerate Elkhart Lake UARTs via dedicated driver From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> commit 7f0909db761535aefafa77031062603a71557267 upstream. Elkhart Lake UARTs are PCI enumerated Synopsys DesignWare v4.0+ UART integrated with Intel iDMA 32-bit DMA controller. There is a specific driver to handle them, i.e. 8250_lpss. Hence, disable 8250_pci enumeration for these UARTs. Fixes: 1b91d97c66ef ("serial: 8250_lpss: Add ->setup() for Elkhart Lake ports") Fixes: 4f912b898dc2 ("serial: 8250_lpss: Enable HS UART on Elkhart Lake") Cc: stable <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20210713101739.36962-1-andriy.shevchenko@xxxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/tty/serial/8250/8250_pci.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/drivers/tty/serial/8250/8250_pci.c +++ b/drivers/tty/serial/8250/8250_pci.c @@ -3763,6 +3763,12 @@ static const struct pci_device_id blackl { PCI_VDEVICE(INTEL, 0x0f0c), }, { PCI_VDEVICE(INTEL, 0x228a), }, { PCI_VDEVICE(INTEL, 0x228c), }, + { PCI_VDEVICE(INTEL, 0x4b96), }, + { PCI_VDEVICE(INTEL, 0x4b97), }, + { PCI_VDEVICE(INTEL, 0x4b98), }, + { PCI_VDEVICE(INTEL, 0x4b99), }, + { PCI_VDEVICE(INTEL, 0x4b9a), }, + { PCI_VDEVICE(INTEL, 0x4b9b), }, { PCI_VDEVICE(INTEL, 0x9ce3), }, { PCI_VDEVICE(INTEL, 0x9ce4), }, Patches currently in stable-queue which might be from andriy.shevchenko@xxxxxxxxxxxxxxx are queue-5.4/serial-8250_pci-enumerate-elkhart-lake-uarts-via-dedicated-driver.patch