[RFC,lora-next,5/5] HACK: net: lora: sx130x: Add PicoCell gateway shim for cdc-acm

diff --git a/drivers/net/lora/Makefile b/drivers/net/lora/Makefile
index 5fef38abf5ed..bdcf7560dd65 100644
--- a/drivers/net/lora/Makefile
+++ b/drivers/net/lora/Makefile
@@ -27,6 +27,8 @@  lora-sx130x-y := sx130x.o
 lora-sx130x-y += sx130x_radio.o
 obj-$(CONFIG_LORA_SX130X) += lora-sx130x-picogw.o
 lora-sx130x-picogw-y := sx130x_picogw.o
+obj-$(CONFIG_LORA_SX130X) += lora-picogw.o
+lora-picogw-y := picogw.o
 
 obj-$(CONFIG_LORA_USI) += lora-usi.o
 lora-usi-y := usi.o
diff --git a/drivers/net/lora/picogw.c b/drivers/net/lora/picogw.c
new file mode 100644
index 000000000000..aa5b83d21bb3
--- /dev/null
+++ b/drivers/net/lora/picogw.c
@@ -0,0 +1,337 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Semtech PicoCell gateway USB interface
+ *
+ * Copyright (c) 2018-2019 Andreas Färber
+ */
+
+#define pr_fmt(fmt) "picocell: " fmt
+
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/serial.h>
+#include <linux/slab.h>
+#include <linux/tty.h>
+#include <linux/usb.h>
+#include <linux/usb/cdc.h>
+
+#define PICO_VID 0x0483
+#define PICO_PID 0x5740
+
+static struct usb_driver *picogw_get_acm_driver(struct usb_interface *iface)
+{
+	struct device_driver *drv;
+
+	drv = driver_find("cdc_acm", iface->dev.bus);
+	if (!drv)
+		return NULL;
+
+	return to_usb_driver(drv);
+}
+
+static void picogw_kobj_release(struct kobject *kobj)
+{
+	struct device_node *node = container_of(kobj, struct device_node, kobj);
+	struct property *prop;
+
+	prop = node->properties;
+	while (prop) {
+		struct property *next = prop->next;
+		kfree(prop);
+		prop = next;
+	}
+
+	kfree(node);
+}
+
+static struct kobj_type picogw_kobj_type = {
+	.release = picogw_kobj_release,
+};
+
+static u32 picogw_radio_a_reg = cpu_to_be32(0);
+static u32 picogw_radio_b_reg = cpu_to_be32(1);
+
+static int picogw_fake_of_nodes(struct device *dev)
+{
+	struct device_node *node = NULL;
+	struct device_node *child, *spi, *radio_a, *radio_b;
+	struct property *prop;
+
+	node = kzalloc(sizeof(*node), GFP_KERNEL);
+	if (!node)
+		return -ENOMEM;
+	node->name = "<NULL>";
+	node->full_name = "usb0483,5740";
+	node->type = "<NULL>";
+	kobject_init(&node->kobj, &picogw_kobj_type);
+	node->fwnode.ops = &of_fwnode_ops;
+
+	child = kzalloc(sizeof(*child), GFP_KERNEL);
+	if (!child) {
+		of_node_put(node);
+		return -ENOMEM;
+	}
+	child->name = "lora";
+	child->full_name = "lora";
+	child->type = "<NULL>";
+	child->parent = node;
+	kobject_init(&child->kobj, &picogw_kobj_type);
+	child->fwnode.ops = &of_fwnode_ops;
+	node->child = child;
+
+	prop = kzalloc(sizeof(*prop), GFP_KERNEL);
+	if (!prop) {
+		of_node_put(child);
+		of_node_put(node);
+		return -ENOMEM;
+	}
+	prop->name = "compatible";
+	prop->value = "semtech,lora-picocell";
+	prop->length = 22;
+	child->properties = prop;
+
+	spi = kzalloc(sizeof(*spi), GFP_KERNEL);
+	if (!spi) {
+		of_node_put(child);
+		of_node_put(node);
+		return -ENOMEM;
+	}
+	spi->name = "radio-spi";
+	spi->full_name = "radio-spi";
+	spi->type = "<NULL>";
+	spi->parent = child;
+	kobject_init(&spi->kobj, &picogw_kobj_type);
+	spi->fwnode.ops = &of_fwnode_ops;
+	child->child = spi;
+
+	radio_a = kzalloc(sizeof(*radio_a), GFP_KERNEL);
+	if (!radio_a) {
+		of_node_put(spi);
+		of_node_put(child);
+		of_node_put(node);
+		return -ENOMEM;
+	}
+	radio_a->name = "lora@0";
+	radio_a->full_name = "lora@0";
+	radio_a->type = "<NULL>";
+	radio_a->parent = spi;
+	kobject_init(&radio_a->kobj, &picogw_kobj_type);
+	radio_a->fwnode.ops = &of_fwnode_ops;
+	spi->child = radio_a;
+
+	prop = kzalloc(sizeof(*prop), GFP_KERNEL);
+	if (!prop) {
+		of_node_put(radio_a);
+		of_node_put(spi);
+		of_node_put(child);
+		of_node_put(node);
+		return -ENOMEM;
+	}
+	prop->name = "compatible";
+	prop->value = "semtech,sx1257";
+	prop->length = 15;
+	radio_a->properties = prop;
+
+	prop = kzalloc(sizeof(*prop), GFP_KERNEL);
+	if (!prop) {
+		of_node_put(radio_a);
+		of_node_put(spi);
+		of_node_put(child);
+		of_node_put(node);
+		return -ENOMEM;
+	}
+	prop->name = "reg";
+	prop->value = &picogw_radio_a_reg;
+	prop->length = 4;
+	radio_a->properties->next = prop;
+
+	radio_b = kzalloc(sizeof(*radio_b), GFP_KERNEL);
+	if (!radio_b) {
+		of_node_put(radio_a);
+		of_node_put(spi);
+		of_node_put(child);
+		of_node_put(node);
+		return -ENOMEM;
+	}
+	radio_b->name = "lora@1";
+	radio_b->full_name = "Lora@1";
+	radio_b->type = "<NULL>";
+	radio_b->parent = spi;
+	kobject_init(&radio_b->kobj, &picogw_kobj_type);
+	radio_b->fwnode.ops = &of_fwnode_ops;
+	radio_a->sibling = radio_b;
+
+	prop = kzalloc(sizeof(*prop), GFP_KERNEL);
+	if (!prop) {
+		of_node_put(radio_b);
+		of_node_put(radio_a);
+		of_node_put(spi);
+		of_node_put(child);
+		of_node_put(node);
+		return -ENOMEM;
+	}
+	prop->name = "compatible";
+	prop->value = "semtech,sx1257";
+	prop->length = 15;
+	radio_b->properties = prop;
+
+	prop = kzalloc(sizeof(*prop), GFP_KERNEL);
+	if (!prop) {
+		of_node_put(radio_a);
+		of_node_put(spi);
+		of_node_put(child);
+		of_node_put(node);
+		return -ENOMEM;
+	}
+	prop->name = "reg";
+	prop->value = &picogw_radio_b_reg;
+	prop->length = 4;
+	radio_b->properties->next = prop;
+
+	dev->of_node = node;
+
+	return 0;
+}
+
+static void picogw_cleanup_of_nodes(struct device *dev)
+{
+	if (dev->of_node->parent)
+		return;
+
+	of_node_put(dev->of_node->child->child->child->sibling); /* lora@1 */
+	of_node_put(dev->of_node->child->child->child); /* lora@0 */
+	of_node_put(dev->of_node->child->child); /* radio-spi*/
+	of_node_put(dev->of_node->child); /* serdev */
+	of_node_put(dev->of_node); /* usb */
+	dev->of_node = NULL;
+}
+
+static int picogw_probe(struct usb_interface *interface,
+	const struct usb_device_id *id)
+{
+	struct usb_driver *drv;
+	int ret;
+
+	drv = picogw_get_acm_driver(interface);
+	if (!drv) {
+		dev_err(&interface->dev, "driver_find failed\n");
+		return -EPROBE_DEFER;
+	}
+
+	if (!interface->dev.of_node) {
+		dev_dbg(&interface->dev, "no of_node\n");
+		ret = picogw_fake_of_nodes(&interface->dev);
+		if (ret)
+			return ret;
+	}
+
+	ret = drv->probe(interface, id);
+	if (ret) {
+		picogw_cleanup_of_nodes(&interface->dev);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void picogw_disconnect(struct usb_interface *intf)
+{
+	struct usb_driver *drv = picogw_get_acm_driver(intf);
+
+	if (drv)
+		drv->disconnect(intf);
+	else
+		dev_warn(&intf->dev, "%s: failed to get cdc_acm driver\n", __func__);
+
+	picogw_cleanup_of_nodes(&intf->dev);
+}
+
+static int picogw_suspend(struct usb_interface *intf, pm_message_t message)
+{
+	struct usb_driver *drv = picogw_get_acm_driver(intf);
+
+	if (!drv) {
+		dev_err(&intf->dev, "%s: failed to get cdc_acm driver\n", __func__);
+		return -ENODEV;
+	}
+
+	return drv->suspend(intf, message);
+}
+
+static int picogw_resume(struct usb_interface *intf)
+{
+	struct usb_driver *drv = picogw_get_acm_driver(intf);
+
+	if (!drv) {
+		dev_err(&intf->dev, "%s: failed to get cdc_acm driver\n", __func__);
+		return -ENODEV;
+	}
+
+	return drv->resume(intf);
+}
+
+static int picogw_reset_resume(struct usb_interface *intf)
+{
+	struct usb_driver *drv = picogw_get_acm_driver(intf);
+
+	if (!drv) {
+		dev_err(&intf->dev, "%s: failed to get cdc_acm driver\n", __func__);
+		return -ENODEV;
+	}
+
+	return drv->reset_resume(intf);
+}
+
+static int picogw_pre_reset(struct usb_interface *intf)
+{
+	struct usb_driver *drv = picogw_get_acm_driver(intf);
+
+	if (!drv) {
+		dev_err(&intf->dev, "%s: failed to get cdc_acm driver\n", __func__);
+		return -ENODEV;
+	}
+
+	return drv->pre_reset(intf);
+}
+
+static const struct usb_device_id picogw_usb_id_table[] = {
+	{ USB_DEVICE_AND_INTERFACE_INFO(PICO_VID, PICO_PID,
+	  USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM, USB_CDC_ACM_PROTO_AT_V25TER) },
+	{}
+};
+MODULE_DEVICE_TABLE(usb, picogw_usb_id_table);
+
+static struct usb_driver picogw_usb_driver = {
+	.name = "lora-picogw-usb",
+	.probe = picogw_probe,
+	.disconnect = picogw_disconnect,
+	.suspend = picogw_suspend,
+	.resume = picogw_resume,
+	.reset_resume = picogw_reset_resume,
+	.pre_reset = picogw_pre_reset,
+	.id_table = picogw_usb_id_table,
+	.supports_autosuspend = 1,
+	.disable_hub_initiated_lpm = 1,
+};
+
+static int __init picogw_init(void)
+{
+	int ret;
+
+	ret = usb_register(&picogw_usb_driver);
+	if (ret < 0){
+		pr_err("usb_register failed (%d)\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+module_init(picogw_init);
+
+static void __exit picogw_exit(void)
+{
+	usb_deregister(&picogw_usb_driver);
+}
+module_exit(picogw_exit);
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index c225a586c524..541c23b4fbfe 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -1865,6 +1865,10 @@  static const struct usb_device_id acm_ids[] = {
 	.driver_info = IGNORE_DEVICE,
 	},
 
+	{ USB_DEVICE_AND_INTERFACE_INFO(0x0483, 0x5740,
+		USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM, USB_CDC_ACM_PROTO_AT_V25TER),
+	.driver_info = IGNORE_DEVICE },
+
 	/* control interfaces without any protocol set */
 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
 		USB_CDC_PROTO_NONE) },