6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
commit 166ac2bba167d575e7146beaa66093bc7c072f43 upstream.
Currently the ->iotype is always assigned to the UPIO_MEM when
the respective property is not found. However, this will not
support the cases when user wants to have UPIO_PORT to be set
or preserved. Support this scenario by checking ->iobase value
and default the ->iotype respectively.
Fixes: 1117a6fdc7c1 ("serial: 8250_of: Switch to use uart_read_port_properties()")
Fixes: e894b6005dce ("serial: port: Introduce a common helper to read properties")
Cc: stable <stable@xxxxxxxxxx>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20250124161530.398361-2-andriy.shevchenko@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/tty/serial/serial_port.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/tty/serial/serial_port.c
+++ b/drivers/tty/serial/serial_port.c
@@ -172,6 +172,7 @@ EXPORT_SYMBOL(uart_remove_one_port);
* The caller is responsible to initialize the following fields of the @port
* ->dev (must be valid)
* ->flags
+ * ->iobase
* ->mapbase
* ->mapsize
* ->regshift (if @use_defaults is false)
@@ -213,7 +214,7 @@ static int __uart_read_properties(struct
/* Read the registers I/O access type (default: MMIO 8-bit) */
ret = device_property_read_u32(dev, "reg-io-width", &value);
if (ret) {
- port->iotype = UPIO_MEM;
+ port->iotype = port->iobase ? UPIO_PORT : UPIO_MEM;
} else {
switch (value) {
case 1:
