// SPDX-License-Identifier: GPL-2.0+ /* * composite.h -- framework for usb gadgets which are composite devices * * Copyright (C) 2006-2008 David Brownell * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef __LINUX_USB_COMPOSITE_H #define __LINUX_USB_COMPOSITE_H /* * This framework is an optional layer on top of the USB Gadget interface, * making it easier to build (a) Composite devices, supporting multiple * functions within any single configuration, and (b) Multi-configuration * devices, also supporting multiple functions but without necessarily * having more than one function per configuration. * * Example: a device with a single configuration supporting both network * link and mass storage functions is a composite device. Those functions * might alternatively be packaged in individual configurations, but in * the composite model the host can use both functions at the same time. */ #include #include #include #include #include #include /* * USB function drivers should return USB_GADGET_DELAYED_STATUS if they * wish to delay the data/status stages of the control transfer till they * are ready. The control transfer will then be kept from completing till * all the function drivers that requested for USB_GADGET_DELAYED_STAUS * invoke usb_composite_setup_continue(). */ #define USB_GADGET_DELAYED_STATUS 0x7fff /* Impossibly large value */ /* big enough to hold our biggest descriptor */ #define USB_COMP_EP0_BUFSIZ 4096 /* OS feature descriptor length <= 4kB */ #define USB_COMP_EP0_OS_DESC_BUFSIZ 4096 #define USB_MS_TO_HS_INTERVAL(x) (ilog2((x * 1000 / 125)) + 1) struct usb_configuration; /** * struct usb_os_desc_ext_prop - describes one "Extended Property" * @entry: used to keep a list of extended properties * @type: Extended Property type * @name_len: Extended Property unicode name length, including terminating '\0' * @name: Extended Property name * @data_len: Length of Extended Property blob (for unicode store double len) * @data: Extended Property blob * @item: Represents this Extended Property in configfs */ struct usb_os_desc_ext_prop { struct list_head entry; u8 type; int name_len; char *name; int data_len; char *data; struct config_item item; }; /** * struct usb_os_desc - describes OS descriptors associated with one interface * @ext_compat_id: 16 bytes of "Compatible ID" and "Subcompatible ID" * @ext_prop: Extended Properties list * @ext_prop_len: Total length of Extended Properties blobs * @ext_prop_count: Number of Extended Properties * @opts_mutex: Optional mutex protecting config data of a usb_function_instance * @group: Represents OS descriptors associated with an interface in configfs * @owner: Module associated with this OS descriptor */ struct usb_os_desc { char *ext_compat_id; struct list_head ext_prop; int ext_prop_len; int ext_prop_count; struct mutex *opts_mutex; struct config_group group; struct module *owner; }; /** * struct usb_os_desc_table - describes OS descriptors associated with one * interface of a usb_function * @if_id: Interface id * @os_desc: "Extended Compatibility ID" and "Extended Properties" of the * interface * * Each interface can have at most one "Extended Compatibility ID" and a * number of "Extended Properties". */ struct usb_os_desc_table { int if_id; struct usb_os_desc *os_desc; }; /** * struct usb_function - describes one function of a configuration * @name: For diagnostics, identifies the function. * @strings: tables of strings, keyed by identifiers assigned during bind() * and by language IDs provided in control requests * @fs_descriptors: Table of full (or low) speed descriptors, using interface and * string identifiers assigned during @bind(). If this pointer is null, * the function will not be available at full speed (or at low speed). * @hs_descriptors: Table of high speed descriptors, using interface and * string identifiers assigned during @bind(). If this pointer is null, * the function will not be available at high speed. * @ss_descriptors: Table of super speed descriptors, using interface and * string identifiers assigned during @bind(). If this * pointer is null after initiation, the function will not * be available at super speed. * @ssp_descriptors: Table of super speed plus descriptors, using * interface and string identifiers assigned during @bind(). If * this pointer is null after initiation, the function will not * be available at super speed plus. * @config: assigned when @usb_add_function() is called; this is the * configuration with which this function is associated. * @os_desc_table: Table of (interface id, os descriptors) pairs. The function * can expose more than one interface. If an interface is a member of * an IAD, only the first interface of IAD has its entry in the table. * @os_desc_n: Number of entries in os_desc_table * @bind: Before the gadget can register, all of its functions bind() to the * available resources including string and interface identifiers used * in interface or class descriptors; endpoints; I/O buffers; and so on. * @unbind: Reverses @bind; called as a side effect of unregistering the * driver which added this function. * @free_func: free the struct usb_function. * @mod: (internal) points to the module that created this structure. * @set_alt: (REQUIRED) Reconfigures altsettings; function drivers may * initialize usb_ep.driver data at this time (when it is used). * Note that setting an interface to its current altsetting resets * interface state, and that all interfaces have a disabled state. * @get_alt: Returns the active altsetting. If this is not provided, * then only altsetting zero is supported. * @disable: (REQUIRED) Indicates the function should be disabled. Reasons * include host resetting or reconfiguring the gadget, and disconnection. * @setup: Used for interface-specific control requests. * @req_match: Tests if a given class request can be handled by this function. * @suspend: Notifies functions when the host stops sending USB traffic. * @resume: Notifies functions when the host restarts USB traffic. * @get_status: Returns function status as a reply to * GetStatus() request when the recipient is Interface. * @func_suspend: callback to be called when * SetFeature(FUNCTION_SUSPEND) is reseived * * A single USB function uses one or more interfaces, and should in most * cases support operation at both full and high speeds. Each function is * associated by @usb_add_function() with a one configuration; that function * causes @bind() to be called so resources can be allocated as part of * setting up a gadget driver. Those resources include endpoints, which * should be allocated using @usb_ep_autoconfig(). * * To support dual speed operation, a function driver provides descriptors * for both high and full speed operation. Except in rare cases that don't * involve bulk endpoints, each speed needs different endpoint descriptors. * * Function drivers choose their own strategies for managing instance data. * The simplest strategy just declares it "static', which means the function * can only be activated once. If the function needs to be exposed in more * than one configuration at a given speed, it needs to support multiple * usb_function structures (one for each configuration). * * A more complex strategy might encapsulate a @usb_function structure inside * a driver-specific instance structure to allows multiple activations. An * example of multiple activations might be a CDC ACM function that supports * two or more distinct instances within the same configuration, providing * several independent logical data links to a USB host. */ struct usb_function { const char *name; struct usb_gadget_strings **strings; struct usb_descriptor_header **fs_descriptors; struct usb_descriptor_header **hs_descriptors; struct usb_descriptor_header **ss_descriptors; struct usb_descriptor_header **ssp_descriptors; struct usb_configuration *config; struct usb_os_desc_table *os_desc_table; unsigned os_desc_n; /* REVISIT: bind() functions can be marked __init, which * makes trouble for section mismatch analysis. See if * we can't restructure things to avoid mismatching. * Related: unbind() may kfree() but bind() won't... */ /* configuration management: bind/unbind */ int (*bind)(struct usb_configuration *, struct usb_function *); void (*unbind)(struct usb_configuration *, struct usb_function *); void (*free_func)(struct usb_function *f); struct module *mod; /* runtime state management */ int (*set_alt)(struct usb_function *, unsigned interface, unsigned alt); int (*get_alt)(struct usb_function *, unsigned interface); void (*disable)(struct usb_function *); int (*setup)(struct usb_function *, const struct usb_ctrlrequest *); bool (*req_match)(struct usb_function *, const struct usb_ctrlrequest *, bool config0); void (*suspend)(struct usb_function *); void (*resume)(struct usb_function *); /* USB 3.0 additions */ int (*get_status)(struct usb_function *); int (*func_suspend)(struct usb_function *, u8 suspend_opt); /* private: */ /* internals */ struct list_head list; DECLARE_BITMAP(endpoints, 32); const struct usb_function_instance *fi; unsigned int bind_deactivated:1; }; int usb_add_function(struct usb_configuration *, struct usb_function *); int usb_function_deactivate(struct usb_function *); int usb_function_activate(struct usb_function *); int usb_interface_id(struct usb_configuration *, struct usb_function *); int config_ep_by_speed(struct usb_gadget *g, struct usb_function *f, struct usb_ep *_ep); #define MAX_CONFIG_INTERFACES 16 /* arbitrary; max 255 */ /** * struct usb_configuration - represents one gadget configuration * @label: For diagnostics, describes the configuration. * @strings: Tables of strings, keyed by identifiers assigned during @bind() * and by language IDs provided in control requests. * @descriptors: Table of descriptors preceding all function descriptors. * Examples include OTG and vendor-specific descriptors. * @unbind: Reverses @bind; called as a side effect of unregistering the * driver which added this configuration. * @setup: Used to delegate control requests that aren't handled by standard * device infrastructure or directed at a specific interface. * @bConfigurationValue: Copied into configuration descriptor. * @iConfiguration: Copied into configuration descriptor. * @bmAttributes: Copied into configuration descriptor. * @MaxPower: Power consumtion in mA. Used to compute bMaxPower in the * configuration descriptor after considering the bus speed. * @cdev: assigned by @usb_add_config() before calling @bind(); this is * the device associated with this configuration. * * Configurations are building blocks for gadget drivers structured around * function drivers. Simple USB gadgets require only one function and one * configuration, and handle dual-speed hardware by always providing the same * functionality. Slightly more complex gadgets may have more than one * single-function configuration at a given speed; or have configurations * that only work at one speed. * * Composite devices are, by definition, ones with configurations which * include more than one function. * * The lifecycle of a usb_configuration includes allocation, initialization * of the fields described above, and calling @usb_add_config() to set up * internal data and bind it to a specific device. The configuration's * @bind() method is then used to initialize all the functions and then * call @usb_add_function() for them. * * Those functions would normally be independent of each other, but that's * not mandatory. CDC WMC devices are an example where functions often * depend on other functions, with some functions subsidiary to others. * Such interdependency may be managed in any way, so long as all of the * descriptors complete by the time the composite driver returns from * its bind() routine. */ struct usb_configuration { const char *label; struct usb_gadget_strings **strings; const struct usb_descriptor_header **descriptors; /* REVISIT: bind() functions can be marked __init, which * makes trouble for section mismatch analysis. See if * we can't restructure things to avoid mismatching... */ /* configuration management: unbind/setup */ void (*unbind)(struct usb_configuration *); int (*setup)(struct usb_configuration *, const struct usb_ctrlrequest *); /* fields in the config descriptor */ u8 bConfigurationValue; u8 iConfiguration; u8 bmAttributes; u16 MaxPower; struct usb_composite_dev *cdev; /* private: */ /* internals */ struct list_head list; struct list_head functions; u8 next_interface_id; unsigned superspeed:1; unsigned highspeed:1; unsigned fullspeed:1; unsigned superspeed_plus:1; struct usb_function *interface[MAX_CONFIG_INTERFACES]; }; int usb_add_config(struct usb_composite_dev *, struct usb_configuration *, int (*)(struct usb_configuration *)); void usb_remove_config(struct usb_composite_dev *, struct usb_configuration *); /* predefined index for usb_composite_driver */ enum { USB_GADGET_MANUFACTURER_IDX = 0, USB_GADGET_PRODUCT_IDX, USB_GADGET_SERIAL_IDX, USB_GADGET_FIRST_AVAIL_IDX, }; /** * struct usb_composite_driver - groups configurations into a gadget * @name: For diagnostics, identifies the driver. * @dev: Template descriptor for the device, including default device * identifiers. * @strings: tables of strings, keyed by identifiers assigned during @bind * and language IDs provided in control requests. Note: The first entries * are predefined. The first entry that may be used is * USB_GADGET_FIRST_AVAIL_IDX * @max_speed: Highest speed the driver supports. * @needs_serial: set to 1 if the gadget needs userspace to provide * a serial number. If one is not provided, warning will be printed. * @bind: (REQUIRED) Used to allocate resources that are shared across the * whole device, such as string IDs, and add its configurations using * @usb_add_config(). This may fail by returning a negative errno * value; it should return zero on successful initialization. * @unbind: Reverses @bind; called as a side effect of unregistering * this driver. * @disconnect: optional driver disconnect method * @suspend: Notifies when the host stops sending USB traffic, * after function notifications * @resume: Notifies configuration when the host restarts USB traffic, * before function notifications * @gadget_driver: Gadget driver controlling this driver * * Devices default to reporting self powered operation. Devices which rely * on bus powered operation should report this in their @bind method. * * Before returning from @bind, various fields in the template descriptor * may be overridden. These include the idVendor/idProduct/bcdDevice values * normally to bind the appropriate host side driver, and the three strings * (iManufacturer, iProduct, iSerialNumber) normally used to provide user * meaningful device identifiers. (The strings will not be defined unless * they are defined in @dev and @strings.) The correct ep0 maxpacket size * is also reported, as defined by the underlying controller driver. */ struct usb_composite_driver { const char *name; const struct usb_device_descriptor *dev; struct usb_gadget_strings **strings; enum usb_device_speed max_speed; unsigned needs_serial:1; int (*bind)(struct usb_composite_dev *cdev); int (*unbind)(struct usb_composite_dev *); void (*disconnect)(struct usb_composite_dev *); /* global suspend hooks */ void (*suspend)(struct usb_composite_dev *); void (*resume)(struct usb_composite_dev *); struct usb_gadget_driver gadget_driver; }; extern int usb_composite_probe(struct usb_composite_driver *driver); extern void usb_composite_unregister(struct usb_composite_driver *driver); /** * module_usb_composite_driver() - Helper macro for registering a USB gadget * composite driver * @__usb_composite_driver: usb_composite_driver struct * * Helper macro for USB gadget composite drivers which do not do anything * special in module init/exit. This eliminates a lot of boilerplate. Each * module may only use this macro once, and calling it replaces module_init() * and module_exit() */ #define module_usb_composite_driver(__usb_composite_driver) \ module_driver(__usb_composite_driver, usb_composite_probe, \ usb_composite_unregister) extern void usb_composite_setup_continue(struct usb_composite_dev *cdev); extern int composite_dev_prepare(struct usb_composite_driver *composite, struct usb_composite_dev *cdev); extern int composite_os_desc_req_prepare(struct usb_composite_dev *cdev, struct usb_ep *ep0); void composite_dev_cleanup(struct usb_composite_dev *cdev); static inline struct usb_composite_driver *to_cdriver( struct usb_gadget_driver *gdrv) { return container_of(gdrv, struct usb_composite_driver, gadget_driver); } #define OS_STRING_QW_SIGN_LEN 14 #define OS_STRING_IDX 0xEE /** * struct usb_composite_device - represents one composite usb gadget * @gadget: read-only, abstracts the gadget's usb peripheral controller * @req: used for control responses; buffer is pre-allocated * @os_desc_req: used for OS descriptors responses; buffer is pre-allocated * @config: the currently active configuration * @qw_sign: qwSignature part of the OS string * @b_vendor_code: bMS_VendorCode part of the OS string * @use_os_string: false by default, interested gadgets set it * @os_desc_config: the configuration to be used with OS descriptors * @setup_pending: true when setup request is queued but not completed * @os_desc_pending: true when os_desc request is queued but not completed * * One of these devices is allocated and initialized before the * associated device driver's bind() is called. * * OPEN ISSUE: it appears that some WUSB devices will need to be * built by combining a normal (wired) gadget with a wireless one. * This revision of the gadget framework should probably try to make * sure doing that won't hurt too much. * * One notion for how to handle Wireless USB devices involves: * * (a) a second gadget here, discovery mechanism TBD, but likely * needing separate "register/unregister WUSB gadget" calls; * (b) updates to usb_gadget to include flags "is it wireless", * "is it wired", plus (presumably in a wrapper structure) * bandgroup and PHY info; * (c) presumably a wireless_ep wrapping a usb_ep, and reporting * wireless-specific parameters like maxburst and maxsequence; * (d) configurations that are specific to wireless links; * (e) function drivers that understand wireless configs and will * support wireless for (additional) function instances; * (f) a function to support association setup (like CBAF), not * necessarily requiring a wireless adapter; * (g) composite device setup that can create one or more wireless * configs, including appropriate association setup support; * (h) more, TBD. */ struct usb_composite_dev { struct usb_gadget *gadget; struct usb_request *req; struct usb_request *os_desc_req; struct usb_configuration *config; /* OS String is a custom (yet popular) extension to the USB standard. */ u8 qw_sign[OS_STRING_QW_SIGN_LEN]; u8 b_vendor_code; struct usb_configuration *os_desc_config; unsigned int use_os_string:1; /* private: */ /* internals */ unsigned int suspended:1; struct usb_device_descriptor desc; struct list_head configs; struct list_head gstrings; struct usb_composite_driver *driver; u8 next_string_id; char *def_manufacturer; /* the gadget driver won't enable the data pullup * while the deactivation count is nonzero. */ unsigned deactivations; /* the composite driver won't complete the control transfer's * data/status stages till delayed_status is zero. */ int delayed_status; /* protects deactivations and delayed_status counts*/ spinlock_t lock; /* public: */ unsigned int setup_pending:1; unsigned int os_desc_pending:1; }; extern int usb_string_id(struct usb_composite_dev *c); extern int usb_string_ids_tab(struct usb_composite_dev *c, struct usb_string *str); extern struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev, struct usb_gadget_strings **sp, unsigned n_strings); extern int usb_string_ids_n(struct usb_composite_dev *c, unsigned n); extern void composite_disconnect(struct usb_gadget *gadget); extern int composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl); extern void composite_suspend(struct usb_gadget *gadget); extern void composite_resume(struct usb_gadget *gadget); /* * Some systems will need runtime overrides for the product identifiers * published in the device descriptor, either numbers or strings or both. * String parameters are in UTF-8 (superset of ASCII's 7 bit characters). */ struct usb_composite_overwrite { u16 idVendor; u16 idProduct; u16 bcdDevice; char *serial_number; char *manufacturer; char *product; }; #define USB_GADGET_COMPOSITE_OPTIONS() \ static struct usb_composite_overwrite coverwrite; \ \ module_param_named(idVendor, coverwrite.idVendor, ushort, S_IRUGO); \ MODULE_PARM_DESC(idVendor, "USB Vendor ID"); \ \ module_param_named(idProduct, coverwrite.idProduct, ushort, S_IRUGO); \ MODULE_PARM_DESC(idProduct, "USB Product ID"); \ \ module_param_named(bcdDevice, coverwrite.bcdDevice, ushort, S_IRUGO); \ MODULE_PARM_DESC(bcdDevice, "USB Device version (BCD)"); \ \ module_param_named(iSerialNumber, coverwrite.serial_number, charp, \ S_IRUGO); \ MODULE_PARM_DESC(iSerialNumber, "SerialNumber string"); \ \ module_param_named(iManufacturer, coverwrite.manufacturer, charp, \ S_IRUGO); \ MODULE_PARM_DESC(iManufacturer, "USB Manufacturer string"); \ \ module_param_named(iProduct, coverwrite.product, charp, S_IRUGO); \ MODULE_PARM_DESC(iProduct, "USB Product string") void usb_composite_overwrite_options(struct usb_composite_dev *cdev, struct usb_composite_overwrite *covr); static inline u16 get_default_bcdDevice(void) { u16 bcdDevice; bcdDevice = bin2bcd((LINUX_VERSION_CODE >> 16 & 0xff)) << 8; bcdDevice |= bin2bcd((LINUX_VERSION_CODE >> 8 & 0xff)); return bcdDevice; } struct usb_function_driver { const char *name; struct module *mod; struct list_head list; struct usb_function_instance *(*alloc_inst)(void); struct usb_function *(*alloc_func)(struct usb_function_instance *inst); }; struct usb_function_instance { struct config_group group; struct list_head cfs_list; struct usb_function_driver *fd; int (*set_inst_name)(struct usb_function_instance *inst, const char *name); void (*free_func_inst)(struct usb_function_instance *inst); }; void usb_function_unregister(struct usb_function_driver *f); int usb_function_register(struct usb_function_driver *newf); void usb_put_function_instance(struct usb_function_instance *fi); void usb_put_function(struct usb_function *f); struct usb_function_instance *usb_get_function_instance(const char *name); struct usb_function *usb_get_function(struct usb_function_instance *fi); struct usb_configuration *usb_get_config(struct usb_composite_dev *cdev, int val); int usb_add_config_only(struct usb_composite_dev *cdev, struct usb_configuration *config); void usb_remove_function(struct usb_configuration *c, struct usb_function *f); #define DECLARE_USB_FUNCTION(_name, _inst_alloc, _func_alloc) \ static struct usb_function_driver _name ## usb_func = { \ .name = __stringify(_name), \ .mod = THIS_MODULE, \ .alloc_inst = _inst_alloc, \ .alloc_func = _func_alloc, \ }; \ MODULE_ALIAS("usbfunc:"__stringify(_name)); #define DECLARE_USB_FUNCTION_INIT(_name, _inst_alloc, _func_alloc) \ DECLARE_USB_FUNCTION(_name, _inst_alloc, _func_alloc) \ static int __init _name ## mod_init(void) \ { \ return usb_function_register(&_name ## usb_func); \ } \ static void __exit _name ## mod_exit(void) \ { \ usb_function_unregister(&_name ## usb_func); \ } \ module_init(_name ## mod_init); \ module_exit(_name ## mod_exit) /* messaging utils */ #define DBG(d, fmt, args...) \ dev_dbg(&(d)->gadget->dev , fmt , ## args) #define VDBG(d, fmt, args...) \ dev_vdbg(&(d)->gadget->dev , fmt , ## args) #define ERROR(d, fmt, args...) \ dev_err(&(d)->gadget->dev , fmt , ## args) #define WARNING(d, fmt, args...) \ dev_warn(&(d)->gadget->dev , fmt , ## args) #define INFO(d, fmt, args...) \ dev_info(&(d)->gadget->dev , fmt , ## args) #endif /* __LINUX_USB_COMPOSITE_H */