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-rw-r--r--drivers/usb/gadget/legacy/ether.c484
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");