184a9582fSTony Lindgren // SPDX-License-Identifier: GPL-2.0+
284a9582fSTony Lindgren /*
384a9582fSTony Lindgren * Serial base bus layer for controllers
484a9582fSTony Lindgren *
584a9582fSTony Lindgren * Copyright (C) 2023 Texas Instruments Incorporated - https://www.ti.com/
684a9582fSTony Lindgren * Author: Tony Lindgren <tony@atomide.com>
784a9582fSTony Lindgren *
884a9582fSTony Lindgren * The serial core bus manages the serial core controller instances.
984a9582fSTony Lindgren */
1084a9582fSTony Lindgren
1184a9582fSTony Lindgren #include <linux/container_of.h>
1284a9582fSTony Lindgren #include <linux/device.h>
13*04c7f60cSTony Lindgren #include <linux/idr.h>
1484a9582fSTony Lindgren #include <linux/module.h>
1584a9582fSTony Lindgren #include <linux/serial_core.h>
1684a9582fSTony Lindgren #include <linux/slab.h>
1784a9582fSTony Lindgren #include <linux/spinlock.h>
1884a9582fSTony Lindgren
1984a9582fSTony Lindgren #include "serial_base.h"
2084a9582fSTony Lindgren
2153991424STony Lindgren static bool serial_base_initialized;
2253991424STony Lindgren
231ef2c2dfSTony Lindgren static const struct device_type serial_ctrl_type = {
241ef2c2dfSTony Lindgren .name = "ctrl",
251ef2c2dfSTony Lindgren };
261ef2c2dfSTony Lindgren
271ef2c2dfSTony Lindgren static const struct device_type serial_port_type = {
281ef2c2dfSTony Lindgren .name = "port",
291ef2c2dfSTony Lindgren };
301ef2c2dfSTony Lindgren
serial_base_match(struct device * dev,struct device_driver * drv)3184a9582fSTony Lindgren static int serial_base_match(struct device *dev, struct device_driver *drv)
3284a9582fSTony Lindgren {
337d695d83STony Lindgren if (dev->type == &serial_ctrl_type &&
347d695d83STony Lindgren str_has_prefix(drv->name, serial_ctrl_type.name))
357d695d83STony Lindgren return 1;
3684a9582fSTony Lindgren
377d695d83STony Lindgren if (dev->type == &serial_port_type &&
387d695d83STony Lindgren str_has_prefix(drv->name, serial_port_type.name))
397d695d83STony Lindgren return 1;
407d695d83STony Lindgren
417d695d83STony Lindgren return 0;
4284a9582fSTony Lindgren }
4384a9582fSTony Lindgren
4484a9582fSTony Lindgren static struct bus_type serial_base_bus_type = {
4584a9582fSTony Lindgren .name = "serial-base",
4684a9582fSTony Lindgren .match = serial_base_match,
4784a9582fSTony Lindgren };
4884a9582fSTony Lindgren
serial_base_driver_register(struct device_driver * driver)4984a9582fSTony Lindgren int serial_base_driver_register(struct device_driver *driver)
5084a9582fSTony Lindgren {
5184a9582fSTony Lindgren driver->bus = &serial_base_bus_type;
5284a9582fSTony Lindgren
5384a9582fSTony Lindgren return driver_register(driver);
5484a9582fSTony Lindgren }
5584a9582fSTony Lindgren
serial_base_driver_unregister(struct device_driver * driver)5684a9582fSTony Lindgren void serial_base_driver_unregister(struct device_driver *driver)
5784a9582fSTony Lindgren {
5884a9582fSTony Lindgren driver_unregister(driver);
5984a9582fSTony Lindgren }
6084a9582fSTony Lindgren
serial_base_device_init(struct uart_port * port,struct device * dev,struct device * parent_dev,const struct device_type * type,void (* release)(struct device * dev),unsigned int ctrl_id,unsigned int port_id)6184a9582fSTony Lindgren static int serial_base_device_init(struct uart_port *port,
6284a9582fSTony Lindgren struct device *dev,
6384a9582fSTony Lindgren struct device *parent_dev,
6484a9582fSTony Lindgren const struct device_type *type,
6584a9582fSTony Lindgren void (*release)(struct device *dev),
661ef2c2dfSTony Lindgren unsigned int ctrl_id,
671ef2c2dfSTony Lindgren unsigned int port_id)
6884a9582fSTony Lindgren {
6984a9582fSTony Lindgren device_initialize(dev);
7084a9582fSTony Lindgren dev->type = type;
7184a9582fSTony Lindgren dev->parent = parent_dev;
7284a9582fSTony Lindgren dev->bus = &serial_base_bus_type;
7384a9582fSTony Lindgren dev->release = release;
7484a9582fSTony Lindgren
75cef09673SDan Carpenter if (!serial_base_initialized) {
76cef09673SDan Carpenter dev_dbg(port->dev, "uart_add_one_port() called before arch_initcall()?\n");
77cef09673SDan Carpenter return -EPROBE_DEFER;
78cef09673SDan Carpenter }
79cef09673SDan Carpenter
801ef2c2dfSTony Lindgren if (type == &serial_ctrl_type)
811ef2c2dfSTony Lindgren return dev_set_name(dev, "%s:%d", dev_name(port->dev), ctrl_id);
8284a9582fSTony Lindgren
831ef2c2dfSTony Lindgren if (type == &serial_port_type)
841ef2c2dfSTony Lindgren return dev_set_name(dev, "%s:%d.%d", dev_name(port->dev),
851ef2c2dfSTony Lindgren ctrl_id, port_id);
861ef2c2dfSTony Lindgren
871ef2c2dfSTony Lindgren return -EINVAL;
881ef2c2dfSTony Lindgren }
8984a9582fSTony Lindgren
serial_base_ctrl_release(struct device * dev)9084a9582fSTony Lindgren static void serial_base_ctrl_release(struct device *dev)
9184a9582fSTony Lindgren {
9284a9582fSTony Lindgren struct serial_ctrl_device *ctrl_dev = to_serial_base_ctrl_device(dev);
9384a9582fSTony Lindgren
9484a9582fSTony Lindgren kfree(ctrl_dev);
9584a9582fSTony Lindgren }
9684a9582fSTony Lindgren
serial_base_ctrl_device_remove(struct serial_ctrl_device * ctrl_dev)9784a9582fSTony Lindgren void serial_base_ctrl_device_remove(struct serial_ctrl_device *ctrl_dev)
9884a9582fSTony Lindgren {
9984a9582fSTony Lindgren if (!ctrl_dev)
10084a9582fSTony Lindgren return;
10184a9582fSTony Lindgren
10284a9582fSTony Lindgren device_del(&ctrl_dev->dev);
1036be1a8d5STony Lindgren put_device(&ctrl_dev->dev);
10484a9582fSTony Lindgren }
10584a9582fSTony Lindgren
serial_base_ctrl_add(struct uart_port * port,struct device * parent)10684a9582fSTony Lindgren struct serial_ctrl_device *serial_base_ctrl_add(struct uart_port *port,
10784a9582fSTony Lindgren struct device *parent)
10884a9582fSTony Lindgren {
10984a9582fSTony Lindgren struct serial_ctrl_device *ctrl_dev;
11084a9582fSTony Lindgren int err;
11184a9582fSTony Lindgren
11284a9582fSTony Lindgren ctrl_dev = kzalloc(sizeof(*ctrl_dev), GFP_KERNEL);
11384a9582fSTony Lindgren if (!ctrl_dev)
11484a9582fSTony Lindgren return ERR_PTR(-ENOMEM);
11584a9582fSTony Lindgren
116*04c7f60cSTony Lindgren ida_init(&ctrl_dev->port_ida);
117*04c7f60cSTony Lindgren
11884a9582fSTony Lindgren err = serial_base_device_init(port, &ctrl_dev->dev,
11984a9582fSTony Lindgren parent, &serial_ctrl_type,
12084a9582fSTony Lindgren serial_base_ctrl_release,
1211ef2c2dfSTony Lindgren port->ctrl_id, 0);
12284a9582fSTony Lindgren if (err)
12352861a3bSDan Carpenter goto err_put_device;
12484a9582fSTony Lindgren
12584a9582fSTony Lindgren err = device_add(&ctrl_dev->dev);
12684a9582fSTony Lindgren if (err)
12784a9582fSTony Lindgren goto err_put_device;
12884a9582fSTony Lindgren
12984a9582fSTony Lindgren return ctrl_dev;
13084a9582fSTony Lindgren
13184a9582fSTony Lindgren err_put_device:
13284a9582fSTony Lindgren put_device(&ctrl_dev->dev);
13384a9582fSTony Lindgren
13484a9582fSTony Lindgren return ERR_PTR(err);
13584a9582fSTony Lindgren }
13684a9582fSTony Lindgren
serial_base_port_release(struct device * dev)13784a9582fSTony Lindgren static void serial_base_port_release(struct device *dev)
13884a9582fSTony Lindgren {
13984a9582fSTony Lindgren struct serial_port_device *port_dev = to_serial_base_port_device(dev);
14084a9582fSTony Lindgren
14184a9582fSTony Lindgren kfree(port_dev);
14284a9582fSTony Lindgren }
14384a9582fSTony Lindgren
serial_base_port_add(struct uart_port * port,struct serial_ctrl_device * ctrl_dev)14484a9582fSTony Lindgren struct serial_port_device *serial_base_port_add(struct uart_port *port,
14584a9582fSTony Lindgren struct serial_ctrl_device *ctrl_dev)
14684a9582fSTony Lindgren {
14784a9582fSTony Lindgren struct serial_port_device *port_dev;
148*04c7f60cSTony Lindgren int min = 0, max = -1; /* Use -1 for max to apply IDA defaults */
14984a9582fSTony Lindgren int err;
15084a9582fSTony Lindgren
15184a9582fSTony Lindgren port_dev = kzalloc(sizeof(*port_dev), GFP_KERNEL);
15284a9582fSTony Lindgren if (!port_dev)
15384a9582fSTony Lindgren return ERR_PTR(-ENOMEM);
15484a9582fSTony Lindgren
155*04c7f60cSTony Lindgren /* Device driver specified port_id vs automatic assignment? */
156*04c7f60cSTony Lindgren if (port->port_id) {
157*04c7f60cSTony Lindgren min = port->port_id;
158*04c7f60cSTony Lindgren max = port->port_id;
159*04c7f60cSTony Lindgren }
160*04c7f60cSTony Lindgren
161*04c7f60cSTony Lindgren err = ida_alloc_range(&ctrl_dev->port_ida, min, max, GFP_KERNEL);
162*04c7f60cSTony Lindgren if (err < 0) {
163*04c7f60cSTony Lindgren kfree(port_dev);
164*04c7f60cSTony Lindgren return ERR_PTR(err);
165*04c7f60cSTony Lindgren }
166*04c7f60cSTony Lindgren
167*04c7f60cSTony Lindgren port->port_id = err;
168*04c7f60cSTony Lindgren
16984a9582fSTony Lindgren err = serial_base_device_init(port, &port_dev->dev,
17084a9582fSTony Lindgren &ctrl_dev->dev, &serial_port_type,
17184a9582fSTony Lindgren serial_base_port_release,
172*04c7f60cSTony Lindgren port->ctrl_id, port->port_id);
17384a9582fSTony Lindgren if (err)
17452861a3bSDan Carpenter goto err_put_device;
17584a9582fSTony Lindgren
17684a9582fSTony Lindgren port_dev->port = port;
17784a9582fSTony Lindgren
17884a9582fSTony Lindgren err = device_add(&port_dev->dev);
17984a9582fSTony Lindgren if (err)
18084a9582fSTony Lindgren goto err_put_device;
18184a9582fSTony Lindgren
18284a9582fSTony Lindgren return port_dev;
18384a9582fSTony Lindgren
18484a9582fSTony Lindgren err_put_device:
18584a9582fSTony Lindgren put_device(&port_dev->dev);
186*04c7f60cSTony Lindgren ida_free(&ctrl_dev->port_ida, port->port_id);
18784a9582fSTony Lindgren
18884a9582fSTony Lindgren return ERR_PTR(err);
18984a9582fSTony Lindgren }
19084a9582fSTony Lindgren
serial_base_port_device_remove(struct serial_port_device * port_dev)19184a9582fSTony Lindgren void serial_base_port_device_remove(struct serial_port_device *port_dev)
19284a9582fSTony Lindgren {
193*04c7f60cSTony Lindgren struct serial_ctrl_device *ctrl_dev;
194*04c7f60cSTony Lindgren struct device *parent;
195*04c7f60cSTony Lindgren
19684a9582fSTony Lindgren if (!port_dev)
19784a9582fSTony Lindgren return;
19884a9582fSTony Lindgren
199*04c7f60cSTony Lindgren parent = port_dev->dev.parent;
200*04c7f60cSTony Lindgren ctrl_dev = to_serial_base_ctrl_device(parent);
201*04c7f60cSTony Lindgren
20284a9582fSTony Lindgren device_del(&port_dev->dev);
203*04c7f60cSTony Lindgren ida_free(&ctrl_dev->port_ida, port_dev->port->port_id);
2046be1a8d5STony Lindgren put_device(&port_dev->dev);
20584a9582fSTony Lindgren }
20684a9582fSTony Lindgren
serial_base_init(void)20784a9582fSTony Lindgren static int serial_base_init(void)
20884a9582fSTony Lindgren {
20984a9582fSTony Lindgren int ret;
21084a9582fSTony Lindgren
21184a9582fSTony Lindgren ret = bus_register(&serial_base_bus_type);
21284a9582fSTony Lindgren if (ret)
21384a9582fSTony Lindgren return ret;
21484a9582fSTony Lindgren
21584a9582fSTony Lindgren ret = serial_base_ctrl_init();
21684a9582fSTony Lindgren if (ret)
21784a9582fSTony Lindgren goto err_bus_unregister;
21884a9582fSTony Lindgren
21984a9582fSTony Lindgren ret = serial_base_port_init();
22084a9582fSTony Lindgren if (ret)
22184a9582fSTony Lindgren goto err_ctrl_exit;
22284a9582fSTony Lindgren
22353991424STony Lindgren serial_base_initialized = true;
22453991424STony Lindgren
22584a9582fSTony Lindgren return 0;
22684a9582fSTony Lindgren
22784a9582fSTony Lindgren err_ctrl_exit:
22884a9582fSTony Lindgren serial_base_ctrl_exit();
22984a9582fSTony Lindgren
23084a9582fSTony Lindgren err_bus_unregister:
23184a9582fSTony Lindgren bus_unregister(&serial_base_bus_type);
23284a9582fSTony Lindgren
23384a9582fSTony Lindgren return ret;
23484a9582fSTony Lindgren }
23553991424STony Lindgren arch_initcall(serial_base_init);
23684a9582fSTony Lindgren
serial_base_exit(void)23784a9582fSTony Lindgren static void serial_base_exit(void)
23884a9582fSTony Lindgren {
23984a9582fSTony Lindgren serial_base_port_exit();
24084a9582fSTony Lindgren serial_base_ctrl_exit();
24184a9582fSTony Lindgren bus_unregister(&serial_base_bus_type);
24284a9582fSTony Lindgren }
24384a9582fSTony Lindgren module_exit(serial_base_exit);
24484a9582fSTony Lindgren
24584a9582fSTony Lindgren MODULE_AUTHOR("Tony Lindgren <tony@atomide.com>");
24684a9582fSTony Lindgren MODULE_DESCRIPTION("Serial core bus");
24784a9582fSTony Lindgren MODULE_LICENSE("GPL");
248