Commit 0ac18dac authored by Crescent Hsieh's avatar Crescent Hsieh Committed by Greg Kroah-Hartman
Browse files

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: 37058fd5 ("tty: serial: 8250: Add support for MOXA Mini PCIe boards")
Cc: stable <stable@kernel.org>
Signed-off-by: default avatarCrescent Hsieh <crescentcy.hsieh@moxa.com>
Reviewed-by: default avatarAndy Shevchenko <andy@kernel.org>
Link: https://lore.kernel.org/r/20240617063058.18866-1-crescentcy.hsieh@moxa.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 6ba59ff4

drivers/tty/serial/8250/8250_pci.c

+12 −1
Original line number Diff line number Diff line
@@ -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)) {