1 files changed, 484 insertions, 0 deletions
diff --git a/drivers/usb/gadget/legacy/ether.c b/drivers/usb/gadget/legacy/ether.c
new file mode 100644
index 000000000..99c7fc0d1
--- /dev/null
+++ b/drivers/usb/gadget/legacy/ether.c
@@ -0,0 +1,484 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * ether.c -- Ethernet gadget driver, with CDC and non-CDC options
+ *
+ * Copyright (C) 2003-2005,2008 David Brownell
+ * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
+ * Copyright (C) 2008 Nokia Corporation
+ */
+
+/* #define VERBOSE_DEBUG */
+
+#include <linux/kernel.h>
+#include <linux/netdevice.h>
+
+#if defined USB_ETH_RNDIS
+#  undef USB_ETH_RNDIS
+#endif
+#ifdef CONFIG_USB_ETH_RNDIS
+#  define USB_ETH_RNDIS y
+#endif
+
+#include "u_ether.h"
+
+
+/*
+ * Ethernet gadget driver -- with CDC and non-CDC options
+ * Builds on hardware support for a full duplex link.
+ *
+ * CDC Ethernet is the standard USB solution for sending Ethernet frames
+ * using USB.  Real hardware tends to use the same framing protocol but look
+ * different for control features.  This driver strongly prefers to use
+ * this USB-IF standard as its open-systems interoperability solution;
+ * most host side USB stacks (except from Microsoft) support it.
+ *
+ * This is sometimes called "CDC ECM" (Ethernet Control Model) to support
+ * TLA-soup.  "CDC ACM" (Abstract Control Model) is for modems, and a new
+ * "CDC EEM" (Ethernet Emulation Model) is starting to spread.
+ *
+ * There's some hardware that can't talk CDC ECM.  We make that hardware
+ * implement a "minimalist" vendor-agnostic CDC core:  same framing, but
+ * link-level setup only requires activating the configuration.  Only the
+ * endpoint descriptors, and product/vendor IDs, are relevant; no control
+ * operations are available.  Linux supports it, but other host operating
+ * systems may not.  (This is a subset of CDC Ethernet.)
+ *
+ * It turns out that if you add a few descriptors to that "CDC Subset",
+ * (Windows) host side drivers from MCCI can treat it as one submode of
+ * a proprietary scheme called "SAFE" ... without needing to know about
+ * specific product/vendor IDs.  So we do that, making it easier to use
+ * those MS-Windows drivers.  Those added descriptors make it resemble a
+ * CDC MDLM device, but they don't change device behavior at all.  (See
+ * MCCI Engineering report 950198 "SAFE Networking Functions".)
+ *
+ * A third option is also in use.  Rather than CDC Ethernet, or something
+ * simpler, Microsoft pushes their own approach: RNDIS.  The published
+ * RNDIS specs are ambiguous and appear to be incomplete, and are also
+ * needlessly complex.  They borrow more from CDC ACM than CDC ECM.
+ */
+
+#define DRIVER_DESC		"Ethernet Gadget"
+#define DRIVER_VERSION		"Memorial Day 2008"
+
+#ifdef USB_ETH_RNDIS
+#define PREFIX			"RNDIS/"
+#else
+#define PREFIX			""
+#endif
+
+/*
+ * This driver aims for interoperability by using CDC ECM unless
+ *
+ *		can_support_ecm()
+ *
+ * returns false, in which case it supports the CDC Subset.  By default,
+ * that returns true; most hardware has no problems with CDC ECM, that's
+ * a good default.  Previous versions of this driver had no default; this
+ * version changes that, removing overhead for new controller support.
+ *
+ *	IF YOUR HARDWARE CAN'T SUPPORT CDC ECM, UPDATE THAT ROUTINE!
+ */
+
+static inline bool has_rndis(void)
+{
+#ifdef	USB_ETH_RNDIS
+	return true;
+#else
+	return false;
+#endif
+}
+
+#include <linux/module.h>
+
+#include "u_ecm.h"
+#include "u_gether.h"
+#ifdef	USB_ETH_RNDIS
+#include "u_rndis.h"
+#include "rndis.h"
+#else
+#define rndis_borrow_net(...) do {} while (0)
+#endif
+#include "u_eem.h"
+
+/*-------------------------------------------------------------------------*/
+USB_GADGET_COMPOSITE_OPTIONS();
+
+USB_ETHERNET_MODULE_PARAMETERS();
+
+/* DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
+ * Instead:  allocate your own, using normal USB-IF procedures.
+ */
+
+/* Thanks to NetChip Technologies for donating this product ID.
+ * It's for devices with only CDC Ethernet configurations.
+ */
+#define CDC_VENDOR_NUM		0x0525	/* NetChip */
+#define CDC_PRODUCT_NUM		0xa4a1	/* Linux-USB Ethernet Gadget */
+
+/* For hardware that can't talk CDC, we use the same vendor ID that
+ * ARM Linux has used for ethernet-over-usb, both with sa1100 and
+ * with pxa250.  We're protocol-compatible, if the host-side drivers
+ * use the endpoint descriptors.  bcdDevice (version) is nonzero, so
+ * drivers that need to hard-wire endpoint numbers have a hook.
+ *
+ * The protocol is a minimal subset of CDC Ether, which works on any bulk
+ * hardware that's not deeply broken ... even on hardware that can't talk
+ * RNDIS (like SA-1100, with no interrupt endpoint, or anything that
+ * doesn't handle control-OUT).
+ */
+#define	SIMPLE_VENDOR_NUM	0x049f
+#define	SIMPLE_PRODUCT_NUM	0x505a
+
+/* For hardware that can talk RNDIS and either of the above protocols,
+ * use this ID ... the windows INF files will know it.  Unless it's
+ * used with CDC Ethernet, Linux 2.4 hosts will need updates to choose
+ * the non-RNDIS configuration.
+ */
+#define RNDIS_VENDOR_NUM	0x0525	/* NetChip */
+#define RNDIS_PRODUCT_NUM	0xa4a2	/* Ethernet/RNDIS Gadget */
+
+/* For EEM gadgets */
+#define EEM_VENDOR_NUM		0x1d6b	/* Linux Foundation */
+#define EEM_PRODUCT_NUM		0x0102	/* EEM Gadget */
+
+/*-------------------------------------------------------------------------*/
+
+static struct usb_device_descriptor device_desc = {
+	.bLength =		sizeof device_desc,
+	.bDescriptorType =	USB_DT_DEVICE,
+
+	/* .bcdUSB = DYNAMIC */
+
+	.bDeviceClass =		USB_CLASS_COMM,
+	.bDeviceSubClass =	0,
+	.bDeviceProtocol =	0,
+	/* .bMaxPacketSize0 = f(hardware) */
+
+	/* Vendor and product id defaults change according to what configs
+	 * we support.  (As does bNumConfigurations.)  These values can
+	 * also be overridden by module parameters.
+	 */
+	.idVendor =		cpu_to_le16 (CDC_VENDOR_NUM),
+	.idProduct =		cpu_to_le16 (CDC_PRODUCT_NUM),
+	/* .bcdDevice = f(hardware) */
+	/* .iManufacturer = DYNAMIC */
+	/* .iProduct = DYNAMIC */
+	/* NO SERIAL NUMBER */
+	.bNumConfigurations =	1,
+};
+
+static const struct usb_descriptor_header *otg_desc[2];
+
+static struct usb_string strings_dev[] = {
+	[USB_GADGET_MANUFACTURER_IDX].s = "",
+	[USB_GADGET_PRODUCT_IDX].s = PREFIX DRIVER_DESC,
+	[USB_GADGET_SERIAL_IDX].s = "",
+	{  } /* end of list */
+};
+
+static struct usb_gadget_strings stringtab_dev = {
+	.language	= 0x0409,	/* en-us */
+	.strings	= strings_dev,
+};
+
+static struct usb_gadget_strings *dev_strings[] = {
+	&stringtab_dev,
+	NULL,
+};
+
+static struct usb_function_instance *fi_ecm;
+static struct usb_function *f_ecm;
+
+static struct usb_function_instance *fi_eem;
+static struct usb_function *f_eem;
+
+static struct usb_function_instance *fi_geth;
+static struct usb_function *f_geth;
+
+static struct usb_function_instance *fi_rndis;
+static struct usb_function *f_rndis;
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * We may not have an RNDIS configuration, but if we do it needs to be
+ * the first one present.  That's to make Microsoft's drivers happy,
+ * and to follow DOCSIS 1.0 (cable modem standard).
+ */
+static int rndis_do_config(struct usb_configuration *c)
+{
+	int status;
+
+	/* FIXME alloc iConfiguration string, set it in c->strings */
+
+	if (gadget_is_otg(c->cdev->gadget)) {
+		c->descriptors = otg_desc;
+		c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
+	}
+
+	f_rndis = usb_get_function(fi_rndis);
+	if (IS_ERR(f_rndis))
+		return PTR_ERR(f_rndis);
+
+	status = usb_add_function(c, f_rndis);
+	if (status < 0)
+		usb_put_function(f_rndis);
+
+	return status;
+}
+
+static struct usb_configuration rndis_config_driver = {
+	.label			= "RNDIS",
+	.bConfigurationValue	= 2,
+	/* .iConfiguration = DYNAMIC */
+	.bmAttributes		= USB_CONFIG_ATT_SELFPOWER,
+};
+
+/*-------------------------------------------------------------------------*/
+
+#ifdef CONFIG_USB_ETH_EEM
+static bool use_eem = 1;
+#else
+static bool use_eem;
+#endif
+module_param(use_eem, bool, 0);
+MODULE_PARM_DESC(use_eem, "use CDC EEM mode");
+
+/*
+ * We _always_ have an ECM, CDC Subset, or EEM configuration.
+ */
+static int eth_do_config(struct usb_configuration *c)
+{
+	int status = 0;
+
+	/* FIXME alloc iConfiguration string, set it in c->strings */
+
+	if (gadget_is_otg(c->cdev->gadget)) {
+		c->descriptors = otg_desc;
+		c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
+	}
+
+	if (use_eem) {
+		f_eem = usb_get_function(fi_eem);
+		if (IS_ERR(f_eem))
+			return PTR_ERR(f_eem);
+
+		status = usb_add_function(c, f_eem);
+		if (status < 0)
+			usb_put_function(f_eem);
+
+		return status;
+	} else if (can_support_ecm(c->cdev->gadget)) {
+		f_ecm = usb_get_function(fi_ecm);
+		if (IS_ERR(f_ecm))
+			return PTR_ERR(f_ecm);
+
+		status = usb_add_function(c, f_ecm);
+		if (status < 0)
+			usb_put_function(f_ecm);
+
+		return status;
+	} else {
+		f_geth = usb_get_function(fi_geth);
+		if (IS_ERR(f_geth))
+			return PTR_ERR(f_geth);
+
+		status = usb_add_function(c, f_geth);
+		if (status < 0)
+			usb_put_function(f_geth);
+
+		return status;
+	}
+
+}
+
+static struct usb_configuration eth_config_driver = {
+	/* .label = f(hardware) */
+	.bConfigurationValue	= 1,
+	/* .iConfiguration = DYNAMIC */
+	.bmAttributes		= USB_CONFIG_ATT_SELFPOWER,
+};
+
+/*-------------------------------------------------------------------------*/
+
+static int eth_bind(struct usb_composite_dev *cdev)
+{
+	struct usb_gadget	*gadget = cdev->gadget;
+	struct f_eem_opts	*eem_opts = NULL;
+	struct f_ecm_opts	*ecm_opts = NULL;
+	struct f_gether_opts	*geth_opts = NULL;
+	struct net_device	*net;
+	int			status;
+
+	/* set up main config label and device descriptor */
+	if (use_eem) {
+		/* EEM */
+		fi_eem = usb_get_function_instance("eem");
+		if (IS_ERR(fi_eem))
+			return PTR_ERR(fi_eem);
+
+		eem_opts = container_of(fi_eem, struct f_eem_opts, func_inst);
+
+		net = eem_opts->net;
+
+		eth_config_driver.label = "CDC Ethernet (EEM)";
+		device_desc.idVendor = cpu_to_le16(EEM_VENDOR_NUM);
+		device_desc.idProduct = cpu_to_le16(EEM_PRODUCT_NUM);
+	} else if (can_support_ecm(gadget)) {
+		/* ECM */
+
+		fi_ecm = usb_get_function_instance("ecm");
+		if (IS_ERR(fi_ecm))
+			return PTR_ERR(fi_ecm);
+
+		ecm_opts = container_of(fi_ecm, struct f_ecm_opts, func_inst);
+
+		net = ecm_opts->net;
+
+		eth_config_driver.label = "CDC Ethernet (ECM)";
+	} else {
+		/* CDC Subset */
+
+		fi_geth = usb_get_function_instance("geth");
+		if (IS_ERR(fi_geth))
+			return PTR_ERR(fi_geth);
+
+		geth_opts = container_of(fi_geth, struct f_gether_opts,
+					 func_inst);
+
+		net = geth_opts->net;
+
+		eth_config_driver.label = "CDC Subset/SAFE";
+
+		device_desc.idVendor = cpu_to_le16(SIMPLE_VENDOR_NUM);
+		device_desc.idProduct = cpu_to_le16(SIMPLE_PRODUCT_NUM);
+		if (!has_rndis())
+			device_desc.bDeviceClass = USB_CLASS_VENDOR_SPEC;
+	}
+
+	gether_set_qmult(net, qmult);
+	if (!gether_set_host_addr(net, host_addr))
+		pr_info("using host ethernet address: %s", host_addr);
+	if (!gether_set_dev_addr(net, dev_addr))
+		pr_info("using self ethernet address: %s", dev_addr);
+
+	if (has_rndis()) {
+		/* RNDIS plus ECM-or-Subset */
+		gether_set_gadget(net, cdev->gadget);
+		status = gether_register_netdev(net);
+		if (status)
+			goto fail;
+
+		if (use_eem)
+			eem_opts->bound = true;
+		else if (can_support_ecm(gadget))
+			ecm_opts->bound = true;
+		else
+			geth_opts->bound = true;
+
+		fi_rndis = usb_get_function_instance("rndis");
+		if (IS_ERR(fi_rndis)) {
+			status = PTR_ERR(fi_rndis);
+			goto fail;
+		}
+
+		rndis_borrow_net(fi_rndis, net);
+
+		device_desc.idVendor = cpu_to_le16(RNDIS_VENDOR_NUM);
+		device_desc.idProduct = cpu_to_le16(RNDIS_PRODUCT_NUM);
+		device_desc.bNumConfigurations = 2;
+	}
+
+	/* Allocate string descriptor numbers ... note that string
+	 * contents can be overridden by the composite_dev glue.
+	 */
+
+	status = usb_string_ids_tab(cdev, strings_dev);
+	if (status < 0)
+		goto fail1;
+	device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
+	device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
+
+	if (gadget_is_otg(gadget) && !otg_desc[0]) {
+		struct usb_descriptor_header *usb_desc;
+
+		usb_desc = usb_otg_descriptor_alloc(gadget);
+		if (!usb_desc) {
+			status = -ENOMEM;
+			goto fail1;
+		}
+		usb_otg_descriptor_init(gadget, usb_desc);
+		otg_desc[0] = usb_desc;
+		otg_desc[1] = NULL;
+	}
+
+	/* register our configuration(s); RNDIS first, if it's used */
+	if (has_rndis()) {
+		status = usb_add_config(cdev, &rndis_config_driver,
+				rndis_do_config);
+		if (status < 0)
+			goto fail2;
+	}
+
+	status = usb_add_config(cdev, &eth_config_driver, eth_do_config);
+	if (status < 0)
+		goto fail2;
+
+	usb_composite_overwrite_options(cdev, &coverwrite);
+	dev_info(&gadget->dev, "%s, version: " DRIVER_VERSION "\n",
+			DRIVER_DESC);
+
+	return 0;
+
+fail2:
+	kfree(otg_desc[0]);
+	otg_desc[0] = NULL;
+fail1:
+	if (has_rndis())
+		usb_put_function_instance(fi_rndis);
+fail:
+	if (use_eem)
+		usb_put_function_instance(fi_eem);
+	else if (can_support_ecm(gadget))
+		usb_put_function_instance(fi_ecm);
+	else
+		usb_put_function_instance(fi_geth);
+	return status;
+}
+
+static int eth_unbind(struct usb_composite_dev *cdev)
+{
+	if (has_rndis()) {
+		usb_put_function(f_rndis);
+		usb_put_function_instance(fi_rndis);
+	}
+	if (use_eem) {
+		usb_put_function(f_eem);
+		usb_put_function_instance(fi_eem);
+	} else if (can_support_ecm(cdev->gadget)) {
+		usb_put_function(f_ecm);
+		usb_put_function_instance(fi_ecm);
+	} else {
+		usb_put_function(f_geth);
+		usb_put_function_instance(fi_geth);
+	}
+	kfree(otg_desc[0]);
+	otg_desc[0] = NULL;
+
+	return 0;
+}
+
+static struct usb_composite_driver eth_driver = {
+	.name		= "g_ether",
+	.dev		= &device_desc,
+	.strings	= dev_strings,
+	.max_speed	= USB_SPEED_SUPER,
+	.bind		= eth_bind,
+	.unbind		= eth_unbind,
+};
+
+module_usb_composite_driver(eth_driver);
+
+MODULE_DESCRIPTION(PREFIX DRIVER_DESC);
+MODULE_AUTHOR("David Brownell, Benedikt Spanger");
+MODULE_LICENSE("GPL");