serial: jsm: fix NPE during jsm_uart_port_init

No device was set which caused serial_base_ctrl_add to crash.

 BUG: kernel NULL pointer dereference, address: 0000000000000050
 Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
 CPU: 16 UID: 0 PID: 368 Comm: (udev-worker) Not tainted 6.12.25-amd64 #1  Debian 6.12.25-1
 RIP: 0010:serial_base_ctrl_add+0x96/0x120
 Call Trace:
  <TASK>
  serial_core_register_port+0x1a0/0x580
  ? __setup_irq+0x39c/0x660
  ? __kmalloc_cache_noprof+0x111/0x310
  jsm_uart_port_init+0xe8/0x180 [jsm]
  jsm_probe_one+0x1f4/0x410 [jsm]
  local_pci_probe+0x42/0x90
  pci_device_probe+0x22f/0x270
  really_probe+0xdb/0x340
  ? pm_runtime_barrier+0x54/0x90
  ? __pfx___driver_attach+0x10/0x10
  __driver_probe_device+0x78/0x110
  driver_probe_device+0x1f/0xa0
  __driver_attach+0xba/0x1c0
  bus_for_each_dev+0x8c/0xe0
  bus_add_driver+0x112/0x1f0
  driver_register+0x72/0xd0
  jsm_init_module+0x36/0xff0 [jsm]
  ? __pfx_jsm_init_module+0x10/0x10 [jsm]
  do_one_initcall+0x58/0x310
  do_init_module+0x60/0x230

Tested with Digi Neo PCIe 8 port card.

Fixes: 84a9582fd203 ("serial: core: Start managing serial controllers to enable runtime PM")
Cc: stable <[email protected]>
Signed-off-by: Dustin Lundquist <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: dlundquist

drivers/tty/serial/jsm/jsm_tty.c

@@ -451,6 +451,7 @@ int jsm_uart_port_init(struct jsm_board *brd)
 		if (!brd->channels[i])
 			continue;
 
+		brd->channels[i]->uart_port.dev = &brd->pci_dev->dev;
 		brd->channels[i]->uart_port.irq = brd->irq;
 		brd->channels[i]->uart_port.uartclk = 14745600;
 		brd->channels[i]->uart_port.type = PORT_JSM;