[PATCH] serial: core: Fix serial_base_match() after fixing controller port name

From: Tony Lindgren
Date: Wed Aug 02 2023 - 07:49:00 EST


While fixing DEVNAME to be more usable, I broke serial_base_match() as
the ctrl and port prefix for device seemed unnecessary.

Let's fix the issue by checking against dev->type and drv->name.

Fixes: 1ef2c2df1199 ("serial: core: Fix serial core controller port name to show controller id")
Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx>
---
drivers/tty/serial/serial_base.h | 3 +++
drivers/tty/serial/serial_base_bus.c | 10 ++++++++--
drivers/tty/serial/serial_ctrl.c | 2 +-
drivers/tty/serial/serial_port.c | 2 +-
4 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/drivers/tty/serial/serial_base.h b/drivers/tty/serial/serial_base.h
--- a/drivers/tty/serial/serial_base.h
+++ b/drivers/tty/serial/serial_base.h
@@ -6,6 +6,9 @@
* Author: Tony Lindgren <tony@xxxxxxxxxxx>
*/

+#define SERIAL_BASE_CTRL_NAME "ctrl"
+#define SERIAL_BASE_PORT_NAME "port"
+
#define to_serial_base_ctrl_device(d) container_of((d), struct serial_ctrl_device, dev)
#define to_serial_base_port_device(d) container_of((d), struct serial_port_device, dev)

diff --git a/drivers/tty/serial/serial_base_bus.c b/drivers/tty/serial/serial_base_bus.c
--- a/drivers/tty/serial/serial_base_bus.c
+++ b/drivers/tty/serial/serial_base_bus.c
@@ -29,9 +29,15 @@ static const struct device_type serial_port_type = {

static int serial_base_match(struct device *dev, struct device_driver *drv)
{
- int len = strlen(drv->name);
+ if (dev->type == &serial_ctrl_type &&
+ !strncmp(SERIAL_BASE_CTRL_NAME, drv->name, 4))
+ return 1;

- return !strncmp(dev_name(dev), drv->name, len);
+ if (dev->type == &serial_port_type &&
+ !strncmp(SERIAL_BASE_PORT_NAME, drv->name, 4))
+ return 1;
+
+ return 0;
}

static struct bus_type serial_base_bus_type = {
diff --git a/drivers/tty/serial/serial_ctrl.c b/drivers/tty/serial/serial_ctrl.c
--- a/drivers/tty/serial/serial_ctrl.c
+++ b/drivers/tty/serial/serial_ctrl.c
@@ -47,7 +47,7 @@ void serial_ctrl_unregister_port(struct uart_driver *drv, struct uart_port *port
}

static struct device_driver serial_ctrl_driver = {
- .name = "ctrl",
+ .name = SERIAL_BASE_CTRL_NAME,
.suppress_bind_attrs = true,
.probe = serial_ctrl_probe,
.remove = serial_ctrl_remove,
diff --git a/drivers/tty/serial/serial_port.c b/drivers/tty/serial/serial_port.c
--- a/drivers/tty/serial/serial_port.c
+++ b/drivers/tty/serial/serial_port.c
@@ -83,7 +83,7 @@ void uart_remove_one_port(struct uart_driver *drv, struct uart_port *port)
EXPORT_SYMBOL(uart_remove_one_port);

static struct device_driver serial_port_driver = {
- .name = "port",
+ .name = SERIAL_BASE_PORT_NAME,
.suppress_bind_attrs = true,
.probe = serial_port_probe,
.remove = serial_port_remove,
--
2.41.0