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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/tty/serial/serial_base_bus.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/tty/serial/serial_base_bus.c')
-rw-r--r--drivers/tty/serial/serial_base_bus.c247
1 files changed, 247 insertions, 0 deletions
diff --git a/drivers/tty/serial/serial_base_bus.c b/drivers/tty/serial/serial_base_bus.c
new file mode 100644
index 0000000000..3dfcf20c4e
--- /dev/null
+++ b/drivers/tty/serial/serial_base_bus.c
@@ -0,0 +1,247 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Serial base bus layer for controllers
+ *
+ * Copyright (C) 2023 Texas Instruments Incorporated - https://www.ti.com/
+ * Author: Tony Lindgren <tony@atomide.com>
+ *
+ * The serial core bus manages the serial core controller instances.
+ */
+
+#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>
+#include <linux/spinlock.h>
+
+#include "serial_base.h"
+
+static bool serial_base_initialized;
+
+static const struct device_type serial_ctrl_type = {
+ .name = "ctrl",
+};
+
+static const struct device_type serial_port_type = {
+ .name = "port",
+};
+
+static int serial_base_match(struct device *dev, struct device_driver *drv)
+{
+ if (dev->type == &serial_ctrl_type &&
+ str_has_prefix(drv->name, serial_ctrl_type.name))
+ return 1;
+
+ if (dev->type == &serial_port_type &&
+ str_has_prefix(drv->name, serial_port_type.name))
+ return 1;
+
+ return 0;
+}
+
+static struct bus_type serial_base_bus_type = {
+ .name = "serial-base",
+ .match = serial_base_match,
+};
+
+int serial_base_driver_register(struct device_driver *driver)
+{
+ driver->bus = &serial_base_bus_type;
+
+ return driver_register(driver);
+}
+
+void serial_base_driver_unregister(struct device_driver *driver)
+{
+ driver_unregister(driver);
+}
+
+static int 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)
+{
+ device_initialize(dev);
+ dev->type = type;
+ dev->parent = parent_dev;
+ dev->bus = &serial_base_bus_type;
+ dev->release = release;
+
+ if (!serial_base_initialized) {
+ dev_dbg(port->dev, "uart_add_one_port() called before arch_initcall()?\n");
+ return -EPROBE_DEFER;
+ }
+
+ if (type == &serial_ctrl_type)
+ return dev_set_name(dev, "%s:%d", dev_name(port->dev), ctrl_id);
+
+ if (type == &serial_port_type)
+ return dev_set_name(dev, "%s:%d.%d", dev_name(port->dev),
+ ctrl_id, port_id);
+
+ return -EINVAL;
+}
+
+static void serial_base_ctrl_release(struct device *dev)
+{
+ struct serial_ctrl_device *ctrl_dev = to_serial_base_ctrl_device(dev);
+
+ kfree(ctrl_dev);
+}
+
+void serial_base_ctrl_device_remove(struct serial_ctrl_device *ctrl_dev)
+{
+ if (!ctrl_dev)
+ return;
+
+ device_del(&ctrl_dev->dev);
+ put_device(&ctrl_dev->dev);
+}
+
+struct serial_ctrl_device *serial_base_ctrl_add(struct uart_port *port,
+ struct device *parent)
+{
+ struct serial_ctrl_device *ctrl_dev;
+ int err;
+
+ ctrl_dev = kzalloc(sizeof(*ctrl_dev), GFP_KERNEL);
+ 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,
+ port->ctrl_id, 0);
+ if (err)
+ goto err_put_device;
+
+ err = device_add(&ctrl_dev->dev);
+ if (err)
+ goto err_put_device;
+
+ return ctrl_dev;
+
+err_put_device:
+ put_device(&ctrl_dev->dev);
+
+ return ERR_PTR(err);
+}
+
+static void serial_base_port_release(struct device *dev)
+{
+ struct serial_port_device *port_dev = to_serial_base_port_device(dev);
+
+ kfree(port_dev);
+}
+
+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->port_id);
+ if (err)
+ goto err_put_device;
+
+ port_dev->port = port;
+
+ err = device_add(&port_dev->dev);
+ if (err)
+ goto err_put_device;
+
+ return port_dev;
+
+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);
+}
+
+static int serial_base_init(void)
+{
+ int ret;
+
+ ret = bus_register(&serial_base_bus_type);
+ if (ret)
+ return ret;
+
+ ret = serial_base_ctrl_init();
+ if (ret)
+ goto err_bus_unregister;
+
+ ret = serial_base_port_init();
+ if (ret)
+ goto err_ctrl_exit;
+
+ serial_base_initialized = true;
+
+ return 0;
+
+err_ctrl_exit:
+ serial_base_ctrl_exit();
+
+err_bus_unregister:
+ bus_unregister(&serial_base_bus_type);
+
+ return ret;
+}
+arch_initcall(serial_base_init);
+
+static void serial_base_exit(void)
+{
+ serial_base_port_exit();
+ serial_base_ctrl_exit();
+ bus_unregister(&serial_base_bus_type);
+}
+module_exit(serial_base_exit);
+
+MODULE_AUTHOR("Tony Lindgren <tony@atomide.com>");
+MODULE_DESCRIPTION("Serial core bus");
+MODULE_LICENSE("GPL");