From: Maciej W. Rozycki macro@orcam.me.uk
commit 637674fa40059cddcc3ad2212728965072f62ea3 upstream.
The EndRun PTP/1588 dual serial port device is based on the Oxford Semiconductor OXPCIe952 UART device with the PCI vendor:device ID set for EndRun Technologies and is therefore driven by a fixed 62.5MHz clock input derived from the 100MHz PCI Express clock. The clock rate is divided by the oversampling rate of 16 as it is supplied to the baud rate generator, yielding the baud base of 3906250.
Replace the incorrect baud base of 4000000 with the right value of 3906250 then, complementing commit 6cbe45d8ac93 ("serial: 8250: Correct the clock for OxSemi PCIe devices").
Signed-off-by: Maciej W. Rozycki macro@orcam.me.uk Cc: stable stable@kernel.org Fixes: 1bc8cde46a159 ("8250_pci: Added driver for Endrun Technologies PTP PCIe card.") Reviewed-by: Andy Shevchenko andy.shevchenko@gmail.com Link: https://lore.kernel.org/r/alpine.DEB.2.21.2204181515270.9383@angie.orcam.me.... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/tty/serial/8250/8250_pci.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
--- a/drivers/tty/serial/8250/8250_pci.c +++ b/drivers/tty/serial/8250/8250_pci.c @@ -2940,7 +2940,7 @@ enum pci_board_num_t { pbn_panacom2, pbn_panacom4, pbn_plx_romulus, - pbn_endrun_2_4000000, + pbn_endrun_2_3906250, pbn_oxsemi, pbn_oxsemi_1_3906250, pbn_oxsemi_2_3906250, @@ -3472,10 +3472,10 @@ static struct pciserial_board pci_boards * signal now many ports are available * 2 port 952 Uart support */ - [pbn_endrun_2_4000000] = { + [pbn_endrun_2_3906250] = { .flags = FL_BASE0, .num_ports = 2, - .base_baud = 4000000, + .base_baud = 3906250, .uart_offset = 0x200, .first_offset = 0x1000, }, @@ -4418,7 +4418,7 @@ static const struct pci_device_id serial */ { PCI_VENDOR_ID_ENDRUN, PCI_DEVICE_ID_ENDRUN_1588, PCI_ANY_ID, PCI_ANY_ID, 0, 0, - pbn_endrun_2_4000000 }, + pbn_endrun_2_3906250 }, /* * Quatech cards. These actually have configurable clocks but for * now we just use the default.