From: Crescent Hsieh Date: Mon, 17 Jun 2024 06:30:58 +0000 (+0800) Subject: tty: serial: 8250: Fix port count mismatch with the device X-Git-Tag: v6.10-rc6~6^2~15 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=0ac18dac43103ab1df6d26ec9a781c0126f83ced;p=thirdparty%2Flinux.git tty: serial: 8250: Fix port count mismatch with the device Normally, the number of ports is indicated by the third digit of the device ID on Moxa PCI serial boards. For example, `0x1121` indicates a device with 2 ports. However, `CP116E_A_A` and `CP116E_A_B` are exceptions; they have 8 ports, but the third digit of the device ID is `6`. This patch introduces a function to retrieve the number of ports on Moxa PCI serial boards, addressing the issue described above. Fixes: 37058fd5d239 ("tty: serial: 8250: Add support for MOXA Mini PCIe boards") Cc: stable Signed-off-by: Crescent Hsieh Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20240617063058.18866-1-crescentcy.hsieh@moxa.com Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/tty/serial/8250/8250_pci.c b/drivers/tty/serial/8250/8250_pci.c index 40af74b55933c..e1d7aa2fa3474 100644 --- a/drivers/tty/serial/8250/8250_pci.c +++ b/drivers/tty/serial/8250/8250_pci.c @@ -1985,6 +1985,17 @@ enum { MOXA_SUPP_RS485 = BIT(2), }; +static unsigned short moxa_get_nports(unsigned short device) +{ + switch (device) { + case PCI_DEVICE_ID_MOXA_CP116E_A_A: + case PCI_DEVICE_ID_MOXA_CP116E_A_B: + return 8; + } + + return FIELD_GET(0x00F0, device); +} + static bool pci_moxa_is_mini_pcie(unsigned short device) { if (device == PCI_DEVICE_ID_MOXA_CP102N || @@ -2038,7 +2049,7 @@ static int pci_moxa_init(struct pci_dev *dev) { unsigned short device = dev->device; resource_size_t iobar_addr = pci_resource_start(dev, 2); - unsigned int num_ports = (device & 0x00F0) >> 4, i; + unsigned int i, num_ports = moxa_get_nports(device); u8 val, init_mode = MOXA_RS232; if (!(pci_moxa_supported_rs(dev) & MOXA_SUPP_RS232)) {