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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/usb/gadget/legacy/ether.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/usb/gadget/legacy/ether.c')
-rw-r--r-- | drivers/usb/gadget/legacy/ether.c | 484 |
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, ð_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"); |