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path: root/drivers/usb/serial/bus.c
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Diffstat (limited to 'drivers/usb/serial/bus.c')
-rw-r--r--drivers/usb/serial/bus.c173
1 files changed, 173 insertions, 0 deletions
diff --git a/drivers/usb/serial/bus.c b/drivers/usb/serial/bus.c
new file mode 100644
index 0000000000..3eb8dc3a1a
--- /dev/null
+++ b/drivers/usb/serial/bus.c
@@ -0,0 +1,173 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * USB Serial Converter Bus specific functions
+ *
+ * Copyright (C) 2002 Greg Kroah-Hartman (greg@kroah.com)
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/tty.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/usb.h>
+#include <linux/usb/serial.h>
+
+static int usb_serial_device_match(struct device *dev,
+ struct device_driver *drv)
+{
+ const struct usb_serial_port *port = to_usb_serial_port(dev);
+ struct usb_serial_driver *driver = to_usb_serial_driver(drv);
+
+ /*
+ * drivers are already assigned to ports in serial_probe so it's
+ * a simple check here.
+ */
+ if (driver == port->serial->type)
+ return 1;
+
+ return 0;
+}
+
+static int usb_serial_device_probe(struct device *dev)
+{
+ struct usb_serial_port *port = to_usb_serial_port(dev);
+ struct usb_serial_driver *driver;
+ struct device *tty_dev;
+ int retval = 0;
+ int minor;
+
+ /* make sure suspend/resume doesn't race against port_probe */
+ retval = usb_autopm_get_interface(port->serial->interface);
+ if (retval)
+ return retval;
+
+ driver = port->serial->type;
+ if (driver->port_probe) {
+ retval = driver->port_probe(port);
+ if (retval)
+ goto err_autopm_put;
+ }
+
+ minor = port->minor;
+ tty_dev = tty_port_register_device(&port->port, usb_serial_tty_driver,
+ minor, dev);
+ if (IS_ERR(tty_dev)) {
+ retval = PTR_ERR(tty_dev);
+ goto err_port_remove;
+ }
+
+ usb_autopm_put_interface(port->serial->interface);
+
+ dev_info(&port->serial->dev->dev,
+ "%s converter now attached to ttyUSB%d\n",
+ driver->description, minor);
+
+ return 0;
+
+err_port_remove:
+ if (driver->port_remove)
+ driver->port_remove(port);
+err_autopm_put:
+ usb_autopm_put_interface(port->serial->interface);
+
+ return retval;
+}
+
+static void usb_serial_device_remove(struct device *dev)
+{
+ struct usb_serial_port *port = to_usb_serial_port(dev);
+ struct usb_serial_driver *driver;
+ int minor;
+ int autopm_err;
+
+ /*
+ * Make sure suspend/resume doesn't race against port_remove.
+ *
+ * Note that no further runtime PM callbacks will be made if
+ * autopm_get fails.
+ */
+ autopm_err = usb_autopm_get_interface(port->serial->interface);
+
+ minor = port->minor;
+ tty_unregister_device(usb_serial_tty_driver, minor);
+
+ driver = port->serial->type;
+ if (driver->port_remove)
+ driver->port_remove(port);
+
+ dev_info(dev, "%s converter now disconnected from ttyUSB%d\n",
+ driver->description, minor);
+
+ if (!autopm_err)
+ usb_autopm_put_interface(port->serial->interface);
+}
+
+static ssize_t new_id_store(struct device_driver *driver,
+ const char *buf, size_t count)
+{
+ struct usb_serial_driver *usb_drv = to_usb_serial_driver(driver);
+ ssize_t retval = usb_store_new_id(&usb_drv->dynids, usb_drv->id_table,
+ driver, buf, count);
+
+ if (retval >= 0 && usb_drv->usb_driver != NULL)
+ retval = usb_store_new_id(&usb_drv->usb_driver->dynids,
+ usb_drv->usb_driver->id_table,
+ &usb_drv->usb_driver->drvwrap.driver,
+ buf, count);
+ return retval;
+}
+
+static ssize_t new_id_show(struct device_driver *driver, char *buf)
+{
+ struct usb_serial_driver *usb_drv = to_usb_serial_driver(driver);
+
+ return usb_show_dynids(&usb_drv->dynids, buf);
+}
+static DRIVER_ATTR_RW(new_id);
+
+static struct attribute *usb_serial_drv_attrs[] = {
+ &driver_attr_new_id.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(usb_serial_drv);
+
+static void free_dynids(struct usb_serial_driver *drv)
+{
+ struct usb_dynid *dynid, *n;
+
+ spin_lock(&drv->dynids.lock);
+ list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) {
+ list_del(&dynid->node);
+ kfree(dynid);
+ }
+ spin_unlock(&drv->dynids.lock);
+}
+
+const struct bus_type usb_serial_bus_type = {
+ .name = "usb-serial",
+ .match = usb_serial_device_match,
+ .probe = usb_serial_device_probe,
+ .remove = usb_serial_device_remove,
+ .drv_groups = usb_serial_drv_groups,
+};
+
+int usb_serial_bus_register(struct usb_serial_driver *driver)
+{
+ int retval;
+
+ driver->driver.bus = &usb_serial_bus_type;
+ spin_lock_init(&driver->dynids.lock);
+ INIT_LIST_HEAD(&driver->dynids.list);
+
+ retval = driver_register(&driver->driver);
+
+ return retval;
+}
+
+void usb_serial_bus_deregister(struct usb_serial_driver *driver)
+{
+ free_dynids(driver);
+ driver_unregister(&driver->driver);
+}
+