diff options
Diffstat (limited to 'drivers/usb/gadget')
| -rw-r--r-- | drivers/usb/gadget/ether.c | 142 |
1 files changed, 103 insertions, 39 deletions
diff --git a/drivers/usb/gadget/ether.c b/drivers/usb/gadget/ether.c index ca8e0ebc79e..72e2b65293c 100644 --- a/drivers/usb/gadget/ether.c +++ b/drivers/usb/gadget/ether.c @@ -72,9 +72,18 @@ * * There's some hardware that can't talk CDC. We make that hardware * implement a "minimalist" vendor-agnostic CDC core: same framing, but - * link-level setup only requires activating the configuration. - * Linux supports it, but other host operating systems may not. - * (This is a subset of CDC Ethernet.) + * 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 @@ -254,6 +263,10 @@ MODULE_PARM_DESC(host_addr, "Host Ethernet Address"); #define DEV_CONFIG_CDC #endif +#ifdef CONFIG_USB_GADGET_S3C2410 +#define DEV_CONFIG_CDC +#endif + #ifdef CONFIG_USB_GADGET_AT91 #define DEV_CONFIG_CDC #endif @@ -283,9 +296,6 @@ MODULE_PARM_DESC(host_addr, "Host Ethernet Address"); #define DEV_CONFIG_SUBSET #endif -#ifdef CONFIG_USB_GADGET_S3C2410 -#define DEV_CONFIG_CDC -#endif /*-------------------------------------------------------------------------*/ @@ -487,8 +497,17 @@ rndis_config = { * endpoint. Both have a "data" interface and two bulk endpoints. * There are also differences in how control requests are handled. * - * RNDIS shares a lot with CDC-Ethernet, since it's a variant of - * the CDC-ACM (modem) spec. + * RNDIS shares a lot with CDC-Ethernet, since it's a variant of the + * CDC-ACM (modem) spec. Unfortunately MSFT's RNDIS driver is buggy; it + * may hang or oops. Since bugfixes (or accurate specs, letting Linux + * work around those bugs) are unlikely to ever come from MSFT, you may + * wish to avoid using RNDIS. + * + * MCCI offers an alternative to RNDIS if you need to connect to Windows + * but have hardware that can't support CDC Ethernet. We add descriptors + * to present the CDC Subset as a (nonconformant) CDC MDLM variant called + * "SAFE". That borrows from both CDC Ethernet and CDC MDLM. You can + * get those drivers from MCCI, or bundled with various products. */ #ifdef DEV_CONFIG_CDC @@ -522,8 +541,6 @@ rndis_control_intf = { }; #endif -#if defined(DEV_CONFIG_CDC) || defined(CONFIG_USB_ETH_RNDIS) - static const struct usb_cdc_header_desc header_desc = { .bLength = sizeof header_desc, .bDescriptorType = USB_DT_CS_INTERFACE, @@ -532,6 +549,8 @@ static const struct usb_cdc_header_desc header_desc = { .bcdCDC = __constant_cpu_to_le16 (0x0110), }; +#if defined(DEV_CONFIG_CDC) || defined(CONFIG_USB_ETH_RNDIS) + static const struct usb_cdc_union_desc union_desc = { .bLength = sizeof union_desc, .bDescriptorType = USB_DT_CS_INTERFACE, @@ -564,7 +583,40 @@ static const struct usb_cdc_acm_descriptor acm_descriptor = { #endif -#ifdef DEV_CONFIG_CDC +#ifndef DEV_CONFIG_CDC + +/* "SAFE" loosely follows CDC WMC MDLM, violating the spec in various + * ways: data endpoints live in the control interface, there's no data + * interface, and it's not used to talk to a cell phone radio. + */ + +static const struct usb_cdc_mdlm_desc mdlm_desc = { + .bLength = sizeof mdlm_desc, + .bDescriptorType = USB_DT_CS_INTERFACE, + .bDescriptorSubType = USB_CDC_MDLM_TYPE, + + .bcdVersion = __constant_cpu_to_le16(0x0100), + .bGUID = { + 0x5d, 0x34, 0xcf, 0x66, 0x11, 0x18, 0x11, 0xd6, + 0xa2, 0x1a, 0x00, 0x01, 0x02, 0xca, 0x9a, 0x7f, + }, +}; + +/* since "usb_cdc_mdlm_detail_desc" is a variable length structure, we + * can't really use its struct. All we do here is say that we're using + * the submode of "SAFE" which directly matches the CDC Subset. + */ +static const u8 mdlm_detail_desc[] = { + 6, + USB_DT_CS_INTERFACE, + USB_CDC_MDLM_DETAIL_TYPE, + + 0, /* "SAFE" */ + 0, /* network control capabilities (none) */ + 0, /* network data capabilities ("raw" encapsulation) */ +}; + +#endif static const struct usb_cdc_ether_desc ether_desc = { .bLength = sizeof ether_desc, @@ -579,7 +631,6 @@ static const struct usb_cdc_ether_desc ether_desc = { .bNumberPowerFilters = 0, }; -#endif #if defined(DEV_CONFIG_CDC) || defined(CONFIG_USB_ETH_RNDIS) @@ -672,6 +723,9 @@ rndis_data_intf = { /* * "Simple" CDC-subset option is a simple vendor-neutral model that most * full speed controllers can handle: one interface, two bulk endpoints. + * + * To assist host side drivers, we fancy it up a bit, and add descriptors + * so some host side drivers will understand it as a "SAFE" variant. */ static const struct usb_interface_descriptor @@ -682,8 +736,8 @@ subset_data_intf = { .bInterfaceNumber = 0, .bAlternateSetting = 0, .bNumEndpoints = 2, - .bInterfaceClass = USB_CLASS_VENDOR_SPEC, - .bInterfaceSubClass = 0, + .bInterfaceClass = USB_CLASS_COMM, + .bInterfaceSubClass = USB_CDC_SUBCLASS_MDLM, .bInterfaceProtocol = 0, .iInterface = STRING_DATA, }; @@ -731,10 +785,15 @@ static const struct usb_descriptor_header *fs_eth_function [11] = { static inline void __init fs_subset_descriptors(void) { #ifdef DEV_CONFIG_SUBSET + /* behavior is "CDC Subset"; extra descriptors say "SAFE" */ fs_eth_function[1] = (struct usb_descriptor_header *) &subset_data_intf; - fs_eth_function[2] = (struct usb_descriptor_header *) &fs_source_desc; - fs_eth_function[3] = (struct usb_descriptor_header *) &fs_sink_desc; - fs_eth_function[4] = NULL; + fs_eth_function[2] = (struct usb_descriptor_header *) &header_desc; + fs_eth_function[3] = (struct usb_descriptor_header *) &mdlm_desc; + fs_eth_function[4] = (struct usb_descriptor_header *) &mdlm_detail_desc; + fs_eth_function[5] = (struct usb_descriptor_header *) ðer_desc; + fs_eth_function[6] = (struct usb_descriptor_header *) &fs_source_desc; + fs_eth_function[7] = (struct usb_descriptor_header *) &fs_sink_desc; + fs_eth_function[8] = NULL; #else fs_eth_function[1] = NULL; #endif @@ -828,10 +887,15 @@ static const struct usb_descriptor_header *hs_eth_function [11] = { static inline void __init hs_subset_descriptors(void) { #ifdef DEV_CONFIG_SUBSET + /* behavior is "CDC Subset"; extra descriptors say "SAFE" */ hs_eth_function[1] = (struct usb_descriptor_header *) &subset_data_intf; - hs_eth_function[2] = (struct usb_descriptor_header *) &fs_source_desc; - hs_eth_function[3] = (struct usb_descriptor_header *) &fs_sink_desc; - hs_eth_function[4] = NULL; + hs_eth_function[2] = (struct usb_descriptor_header *) &header_desc; + hs_eth_function[3] = (struct usb_descriptor_header *) &mdlm_desc; + hs_eth_function[4] = (struct usb_descriptor_header *) &mdlm_detail_desc; + hs_eth_function[5] = (struct usb_descriptor_header *) ðer_desc; + hs_eth_function[6] = (struct usb_descriptor_header *) &hs_source_desc; + hs_eth_function[7] = (struct usb_descriptor_header *) &hs_sink_desc; + hs_eth_function[8] = NULL; #else hs_eth_function[1] = NULL; #endif @@ -878,10 +942,8 @@ static char manufacturer [50]; static char product_desc [40] = DRIVER_DESC; static char serial_number [20]; -#ifdef DEV_CONFIG_CDC /* address that the host will use ... usually assigned at random */ static char ethaddr [2 * ETH_ALEN + 1]; -#endif /* static strings, in UTF-8 */ static struct usb_string strings [] = { @@ -889,9 +951,9 @@ static struct usb_string strings [] = { { STRING_PRODUCT, product_desc, }, { STRING_SERIALNUMBER, serial_number, }, { STRING_DATA, "Ethernet Data", }, + { STRING_ETHADDR, ethaddr, }, #ifdef DEV_CONFIG_CDC { STRING_CDC, "CDC Ethernet", }, - { STRING_ETHADDR, ethaddr, }, { STRING_CONTROL, "CDC Communications Control", }, #endif #ifdef DEV_CONFIG_SUBSET @@ -986,10 +1048,10 @@ set_ether_config (struct eth_dev *dev, gfp_t gfp_flags) } #endif - dev->in = ep_desc (dev->gadget, &hs_source_desc, &fs_source_desc); + dev->in = ep_desc(gadget, &hs_source_desc, &fs_source_desc); dev->in_ep->driver_data = dev; - dev->out = ep_desc (dev->gadget, &hs_sink_desc, &fs_sink_desc); + dev->out = ep_desc(gadget, &hs_sink_desc, &fs_sink_desc); dev->out_ep->driver_data = dev; /* With CDC, the host isn't allowed to use these two data @@ -2278,10 +2340,10 @@ eth_bind (struct usb_gadget *gadget) "RNDIS/%s", driver_desc); /* CDC subset ... recognized by Linux since 2.4.10, but Windows - * drivers aren't widely available. + * drivers aren't widely available. (That may be improved by + * supporting one submode of the "SAFE" variant of MDLM.) */ } else if (!cdc) { - device_desc.bDeviceClass = USB_CLASS_VENDOR_SPEC; device_desc.idVendor = __constant_cpu_to_le16(SIMPLE_VENDOR_NUM); device_desc.idProduct = @@ -2352,6 +2414,10 @@ autoconf_fail: if (!cdc) { eth_config.bNumInterfaces = 1; eth_config.iConfiguration = STRING_SUBSET; + + /* use functions to set these up, in case we're built to work + * with multiple controllers and must override CDC Ethernet. + */ fs_subset_descriptors(); hs_subset_descriptors(); } @@ -2415,22 +2481,20 @@ autoconf_fail: /* Module params for these addresses should come from ID proms. * The host side address is used with CDC and RNDIS, and commonly - * ends up in a persistent config database. + * ends up in a persistent config database. It's not clear if + * host side code for the SAFE thing cares -- its original BLAN + * thing didn't, Sharp never assigned those addresses on Zaurii. */ if (get_ether_addr(dev_addr, net->dev_addr)) dev_warn(&gadget->dev, "using random %s ethernet address\n", "self"); - if (cdc || rndis) { - if (get_ether_addr(host_addr, dev->host_mac)) - dev_warn(&gadget->dev, - "using random %s ethernet address\n", "host"); -#ifdef DEV_CONFIG_CDC - snprintf (ethaddr, sizeof ethaddr, "%02X%02X%02X%02X%02X%02X", - dev->host_mac [0], dev->host_mac [1], - dev->host_mac [2], dev->host_mac [3], - dev->host_mac [4], dev->host_mac [5]); -#endif - } + if (get_ether_addr(host_addr, dev->host_mac)) + dev_warn(&gadget->dev, + "using random %s ethernet address\n", "host"); + snprintf (ethaddr, sizeof ethaddr, "%02X%02X%02X%02X%02X%02X", + dev->host_mac [0], dev->host_mac [1], + dev->host_mac [2], dev->host_mac [3], + dev->host_mac [4], dev->host_mac [5]); if (rndis) { status = rndis_init(); |