Commit 04c7f60c authored by Tony Lindgren's avatar Tony Lindgren Committed by Greg Kroah-Hartman
Browse files

serial: core: Fix serial core port id, including multiport devices 



We want to fix the serial core port DEVNAME to use a port id of the
hardware specific controller port instance instead of the port->line.

For example, the 8250 driver sets up a number of serial8250 ports
initially that can be inherited by the hardware specific driver. At that
the port->line no longer decribes the port's relation to the serial core
controller instance.

Let's fix the issue by assigning port->port_id for each serial core
controller port instance.

Fixes: 7d695d83 ("serial: core: Fix serial_base_match() after fixing controller port name")
Tested-by: default avatarGuenter Roeck <linux@roeck-us.net>
Reviewed-by: default avatarDhruva Gole <d-gole@ti.com>
Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
Reviewed-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230811103648.2826-1-tony@atomide.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 3d9e6f55

drivers/tty/serial/serial_base.h

+1 −0
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ struct device; 


struct serial_ctrl_device {

	struct device dev;

	struct ida port_ida;

};



struct serial_port_device {

drivers/tty/serial/serial_base_bus.c

+27 −1
Original line number Diff line number Diff line
@@ -10,6 +10,7 @@ 


#include <linux/container_of.h>

#include <linux/device.h>

#include <linux/idr.h>

#include <linux/module.h>

#include <linux/serial_core.h>

#include <linux/slab.h>
@@ -112,6 +113,8 @@ struct serial_ctrl_device *serial_base_ctrl_add(struct uart_port *port, 
	if (!ctrl_dev)

		return ERR_PTR(-ENOMEM);



	ida_init(&ctrl_dev->port_ida);



	err = serial_base_device_init(port, &ctrl_dev->dev,

				      parent, &serial_ctrl_type,

				      serial_base_ctrl_release,
@@ -142,16 +145,31 @@ struct serial_port_device *serial_base_port_add(struct uart_port *port, 
						struct serial_ctrl_device *ctrl_dev)

{

	struct serial_port_device *port_dev;

	int min = 0, max = -1;	/* Use -1 for max to apply IDA defaults */

	int err;



	port_dev = kzalloc(sizeof(*port_dev), GFP_KERNEL);

	if (!port_dev)

		return ERR_PTR(-ENOMEM);



	/* Device driver specified port_id vs automatic assignment? */

	if (port->port_id) {

		min = port->port_id;

		max = port->port_id;

	}



	err = ida_alloc_range(&ctrl_dev->port_ida, min, max, GFP_KERNEL);

	if (err < 0) {

		kfree(port_dev);

		return ERR_PTR(err);

	}



	port->port_id = err;



	err = serial_base_device_init(port, &port_dev->dev,

				      &ctrl_dev->dev, &serial_port_type,

				      serial_base_port_release,

				      port->ctrl_id, port->line);

				      port->ctrl_id, port->port_id);

	if (err)

		goto err_put_device;
@@ -165,16 +183,24 @@ struct serial_port_device *serial_base_port_add(struct uart_port *port, 


err_put_device:

	put_device(&port_dev->dev);

	ida_free(&ctrl_dev->port_ida, port->port_id);



	return ERR_PTR(err);

}



void serial_base_port_device_remove(struct serial_port_device *port_dev)

{

	struct serial_ctrl_device *ctrl_dev;

	struct device *parent;



	if (!port_dev)

		return;



	parent = port_dev->dev.parent;

	ctrl_dev = to_serial_base_ctrl_device(parent);



	device_del(&port_dev->dev);

	ida_free(&ctrl_dev->port_ida, port_dev->port->port_id);

	put_device(&port_dev->dev);

}