diff options
Diffstat (limited to 'drivers/usb/gadget/composite.c')
| -rw-r--r-- | drivers/usb/gadget/composite.c | 1041 |
1 files changed, 1041 insertions, 0 deletions
diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c new file mode 100644 index 000000000000..85c876c1f150 --- /dev/null +++ b/drivers/usb/gadget/composite.c @@ -0,0 +1,1041 @@ +/* + * composite.c - infrastructure for Composite USB Gadgets + * + * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +/* #define VERBOSE_DEBUG */ + +#include <linux/kallsyms.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/device.h> + +#include <linux/usb/composite.h> + + +/* + * The code in this file is utility code, used to build a gadget driver + * from one or more "function" drivers, one or more "configuration" + * objects, and a "usb_composite_driver" by gluing them together along + * with the relevant device-wide data. + */ + +/* big enough to hold our biggest descriptor */ +#define USB_BUFSIZ 512 + +static struct usb_composite_driver *composite; + +/* Some systems will need runtime overrides for the product identifers + * published in the device descriptor, either numbers or strings or both. + * String parameters are in UTF-8 (superset of ASCII's 7 bit characters). + */ + +static ushort idVendor; +module_param(idVendor, ushort, 0); +MODULE_PARM_DESC(idVendor, "USB Vendor ID"); + +static ushort idProduct; +module_param(idProduct, ushort, 0); +MODULE_PARM_DESC(idProduct, "USB Product ID"); + +static ushort bcdDevice; +module_param(bcdDevice, ushort, 0); +MODULE_PARM_DESC(bcdDevice, "USB Device version (BCD)"); + +static char *iManufacturer; +module_param(iManufacturer, charp, 0); +MODULE_PARM_DESC(iManufacturer, "USB Manufacturer string"); + +static char *iProduct; +module_param(iProduct, charp, 0); +MODULE_PARM_DESC(iProduct, "USB Product string"); + +static char *iSerialNumber; +module_param(iSerialNumber, charp, 0); +MODULE_PARM_DESC(iSerialNumber, "SerialNumber string"); + +/*-------------------------------------------------------------------------*/ + +/** + * usb_add_function() - add a function to a configuration + * @config: the configuration + * @function: the function being added + * Context: single threaded during gadget setup + * + * After initialization, each configuration must have one or more + * functions added to it. Adding a function involves calling its @bind() + * method to allocate resources such as interface and string identifiers + * and endpoints. + * + * This function returns the value of the function's bind(), which is + * zero for success else a negative errno value. + */ +int __init usb_add_function(struct usb_configuration *config, + struct usb_function *function) +{ + int value = -EINVAL; + + DBG(config->cdev, "adding '%s'/%p to config '%s'/%p\n", + function->name, function, + config->label, config); + + if (!function->set_alt || !function->disable) + goto done; + + function->config = config; + list_add_tail(&function->list, &config->functions); + + /* REVISIT *require* function->bind? */ + if (function->bind) { + value = function->bind(config, function); + if (value < 0) { + list_del(&function->list); + function->config = NULL; + } + } else + value = 0; + + /* We allow configurations that don't work at both speeds. + * If we run into a lowspeed Linux system, treat it the same + * as full speed ... it's the function drivers that will need + * to avoid bulk and ISO transfers. + */ + if (!config->fullspeed && function->descriptors) + config->fullspeed = true; + if (!config->highspeed && function->hs_descriptors) + config->highspeed = true; + +done: + if (value) + DBG(config->cdev, "adding '%s'/%p --> %d\n", + function->name, function, value); + return value; +} + +/** + * usb_interface_id() - allocate an unused interface ID + * @config: configuration associated with the interface + * @function: function handling the interface + * Context: single threaded during gadget setup + * + * usb_interface_id() is called from usb_function.bind() callbacks to + * allocate new interface IDs. The function driver will then store that + * ID in interface, association, CDC union, and other descriptors. It + * will also handle any control requests targetted at that interface, + * particularly changing its altsetting via set_alt(). There may + * also be class-specific or vendor-specific requests to handle. + * + * All interface identifier should be allocated using this routine, to + * ensure that for example different functions don't wrongly assign + * different meanings to the same identifier. Note that since interface + * identifers are configuration-specific, functions used in more than + * one configuration (or more than once in a given configuration) need + * multiple versions of the relevant descriptors. + * + * Returns the interface ID which was allocated; or -ENODEV if no + * more interface IDs can be allocated. + */ +int __init usb_interface_id(struct usb_configuration *config, + struct usb_function *function) +{ + unsigned id = config->next_interface_id; + + if (id < MAX_CONFIG_INTERFACES) { + config->interface[id] = function; + config->next_interface_id = id + 1; + return id; + } + return -ENODEV; +} + +static int config_buf(struct usb_configuration *config, + enum usb_device_speed speed, void *buf, u8 type) +{ + struct usb_config_descriptor *c = buf; + void *next = buf + USB_DT_CONFIG_SIZE; + int len = USB_BUFSIZ - USB_DT_CONFIG_SIZE; + struct usb_function *f; + int status; + + /* write the config descriptor */ + c = buf; + c->bLength = USB_DT_CONFIG_SIZE; + c->bDescriptorType = type; + /* wTotalLength is written later */ + c->bNumInterfaces = config->next_interface_id; + c->bConfigurationValue = config->bConfigurationValue; + c->iConfiguration = config->iConfiguration; + c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes; + c->bMaxPower = config->bMaxPower; + + /* There may be e.g. OTG descriptors */ + if (config->descriptors) { + status = usb_descriptor_fillbuf(next, len, + config->descriptors); + if (status < 0) + return status; + len -= status; + next += status; + } + + /* add each function's descriptors */ + list_for_each_entry(f, &config->functions, list) { + struct usb_descriptor_header **descriptors; + + if (speed == USB_SPEED_HIGH) + descriptors = f->hs_descriptors; + else + descriptors = f->descriptors; + if (!descriptors) + continue; + status = usb_descriptor_fillbuf(next, len, + (const struct usb_descriptor_header **) descriptors); + if (status < 0) + return status; + len -= status; + next += status; + } + + len = next - buf; + c->wTotalLength = cpu_to_le16(len); + return len; +} + +static int config_desc(struct usb_composite_dev *cdev, unsigned w_value) +{ + struct usb_gadget *gadget = cdev->gadget; + struct usb_configuration *c; + u8 type = w_value >> 8; + enum usb_device_speed speed = USB_SPEED_UNKNOWN; + + if (gadget_is_dualspeed(gadget)) { + int hs = 0; + + if (gadget->speed == USB_SPEED_HIGH) + hs = 1; + if (type == USB_DT_OTHER_SPEED_CONFIG) + hs = !hs; + if (hs) + speed = USB_SPEED_HIGH; + + } + + /* This is a lookup by config *INDEX* */ + w_value &= 0xff; + list_for_each_entry(c, &cdev->configs, list) { + /* ignore configs that won't work at this speed */ + if (speed == USB_SPEED_HIGH) { + if (!c->highspeed) + continue; + } else { + if (!c->fullspeed) + continue; + } + if (w_value == 0) + return config_buf(c, speed, cdev->req->buf, type); + w_value--; + } + return -EINVAL; +} + +static int count_configs(struct usb_composite_dev *cdev, unsigned type) +{ + struct usb_gadget *gadget = cdev->gadget; + struct usb_configuration *c; + unsigned count = 0; + int hs = 0; + + if (gadget_is_dualspeed(gadget)) { + if (gadget->speed == USB_SPEED_HIGH) + hs = 1; + if (type == USB_DT_DEVICE_QUALIFIER) + hs = !hs; + } + list_for_each_entry(c, &cdev->configs, list) { + /* ignore configs that won't work at this speed */ + if (hs) { + if (!c->highspeed) + continue; + } else { + if (!c->fullspeed) + continue; + } + count++; + } + return count; +} + +static void device_qual(struct usb_composite_dev *cdev) +{ + struct usb_qualifier_descriptor *qual = cdev->req->buf; + + qual->bLength = sizeof(*qual); + qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER; + /* POLICY: same bcdUSB and device type info at both speeds */ + qual->bcdUSB = cdev->desc.bcdUSB; + qual->bDeviceClass = cdev->desc.bDeviceClass; + qual->bDeviceSubClass = cdev->desc.bDeviceSubClass; + qual->bDeviceProtocol = cdev->desc.bDeviceProtocol; + /* ASSUME same EP0 fifo size at both speeds */ + qual->bMaxPacketSize0 = cdev->desc.bMaxPacketSize0; + qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER); + qual->bRESERVED = 0; +} + +/*-------------------------------------------------------------------------*/ + +static void reset_config(struct usb_composite_dev *cdev) +{ + struct usb_function *f; + + DBG(cdev, "reset config\n"); + + list_for_each_entry(f, &cdev->config->functions, list) { + if (f->disable) + f->disable(f); + } + cdev->config = NULL; +} + +static int set_config(struct usb_composite_dev *cdev, + const struct usb_ctrlrequest *ctrl, unsigned number) +{ + struct usb_gadget *gadget = cdev->gadget; + struct usb_configuration *c = NULL; + int result = -EINVAL; + unsigned power = gadget_is_otg(gadget) ? 8 : 100; + int tmp; + + if (cdev->config) + reset_config(cdev); + + if (number) { + list_for_each_entry(c, &cdev->configs, list) { + if (c->bConfigurationValue == number) { + result = 0; + break; + } + } + if (result < 0) + goto done; + } else + result = 0; + + INFO(cdev, "%s speed config #%d: %s\n", + ({ char *speed; + switch (gadget->speed) { + case USB_SPEED_LOW: speed = "low"; break; + case USB_SPEED_FULL: speed = "full"; break; + case USB_SPEED_HIGH: speed = "high"; break; + default: speed = "?"; break; + } ; speed; }), number, c ? c->label : "unconfigured"); + + if (!c) + goto done; + + cdev->config = c; + + /* Initialize all interfaces by setting them to altsetting zero. */ + for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) { + struct usb_function *f = c->interface[tmp]; + + if (!f) + break; + + result = f->set_alt(f, tmp, 0); + if (result < 0) { + DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n", + tmp, f->name, f, result); + + reset_config(cdev); + goto done; + } + } + + /* when we return, be sure our power usage is valid */ + power = 2 * c->bMaxPower; +done: + usb_gadget_vbus_draw(gadget, power); + return result; +} + +/** + * usb_add_config() - add a configuration to a device. + * @cdev: wraps the USB gadget + * @config: the configuration, with bConfigurationValue assigned + * Context: single threaded during gadget setup + * + * One of the main tasks of a composite driver's bind() routine is to + * add each of the configurations it supports, using this routine. + * + * This function returns the value of the configuration's bind(), which + * is zero for success else a negative errno value. Binding configurations + * assigns global resources including string IDs, and per-configuration + * resources such as interface IDs and endpoints. + */ +int __init usb_add_config(struct usb_composite_dev *cdev, + struct usb_configuration *config) +{ + int status = -EINVAL; + struct usb_configuration *c; + + DBG(cdev, "adding config #%u '%s'/%p\n", + config->bConfigurationValue, + config->label, config); + + if (!config->bConfigurationValue || !config->bind) + goto done; + + /* Prevent duplicate configuration identifiers */ + list_for_each_entry(c, &cdev->configs, list) { + if (c->bConfigurationValue == config->bConfigurationValue) { + status = -EBUSY; + goto done; + } + } + + config->cdev = cdev; + list_add_tail(&config->list, &cdev->configs); + + INIT_LIST_HEAD(&config->functions); + config->next_interface_id = 0; + + status = config->bind(config); + if (status < 0) { + list_del(&config->list); + config->cdev = NULL; + } else { + unsigned i; + + DBG(cdev, "cfg %d/%p speeds:%s%s\n", + config->bConfigurationValue, config, + config->highspeed ? " high" : "", + config->fullspeed + ? (gadget_is_dualspeed(cdev->gadget) + ? " full" + : " full/low") + : ""); + + for (i = 0; i < MAX_CONFIG_INTERFACES; i++) { + struct usb_function *f = config->interface[i]; + + if (!f) + continue; + DBG(cdev, " interface %d = %s/%p\n", + i, f->name, f); + } + } + + /* set_alt(), or next config->bind(), sets up + * ep->driver_data as needed. + */ + usb_ep_autoconfig_reset(cdev->gadget); + +done: + if (status) + DBG(cdev, "added config '%s'/%u --> %d\n", config->label, + config->bConfigurationValue, status); + return status; +} + +/*-------------------------------------------------------------------------*/ + +/* We support strings in multiple languages ... string descriptor zero + * says which languages are supported. The typical case will be that + * only one language (probably English) is used, with I18N handled on + * the host side. + */ + +static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf) +{ + const struct usb_gadget_strings *s; + u16 language; + __le16 *tmp; + + while (*sp) { + s = *sp; + language = cpu_to_le16(s->language); + for (tmp = buf; *tmp && tmp < &buf[126]; tmp++) { + if (*tmp == language) + goto repeat; + } + *tmp++ = language; +repeat: + sp++; + } +} + +static int lookup_string( + struct usb_gadget_strings **sp, + void *buf, + u16 language, + int id +) +{ + struct usb_gadget_strings *s; + int value; + + while (*sp) { + s = *sp++; + if (s->language != language) + continue; + value = usb_gadget_get_string(s, id, buf); + if (value > 0) + return value; + } + return -EINVAL; +} + +static int get_string(struct usb_composite_dev *cdev, + void *buf, u16 language, int id) +{ + struct usb_configuration *c; + struct usb_function *f; + int len; + + /* Yes, not only is USB's I18N support probably more than most + * folk will ever care about ... also, it's all supported here. + * (Except for UTF8 support for Unicode's "Astral Planes".) + */ + + /* 0 == report all available language codes */ + if (id == 0) { + struct usb_string_descriptor *s = buf; + struct usb_gadget_strings **sp; + + memset(s, 0, 256); + s->bDescriptorType = USB_DT_STRING; + + sp = composite->strings; + if (sp) + collect_langs(sp, s->wData); + + list_for_each_entry(c, &cdev->configs, list) { + sp = c->strings; + if (sp) + collect_langs(sp, s->wData); + + list_for_each_entry(f, &c->functions, list) { + sp = f->strings; + if (sp) + collect_langs(sp, s->wData); + } + } + + for (len = 0; s->wData[len] && len <= 126; len++) + continue; + if (!len) + return -EINVAL; + + s->bLength = 2 * (len + 1); + return s->bLength; + } + + /* Otherwise, look up and return a specified string. String IDs + * are device-scoped, so we look up each string table we're told + * about. These lookups are infrequent; simpler-is-better here. + */ + if (composite->strings) { + len = lookup_string(composite->strings, buf, language, id); + if (len > 0) + return len; + } + list_for_each_entry(c, &cdev->configs, list) { + if (c->strings) { + len = lookup_string(c->strings, buf, language, id); + if (len > 0) + return len; + } + list_for_each_entry(f, &c->functions, list) { + if (!f->strings) + continue; + len = lookup_string(f->strings, buf, language, id); + if (len > 0) + return len; + } + } + return -EINVAL; +} + +/** + * usb_string_id() - allocate an unused string ID + * @cdev: the device whose string descriptor IDs are being allocated + * Context: single threaded during gadget setup + * + * @usb_string_id() is called from bind() callbacks to allocate + * string IDs. Drivers for functions, configurations, or gadgets will + * then store that ID in the appropriate descriptors and string table. + * + * All string identifier should be allocated using this routine, to + * ensure that for example different functions don't wrongly assign + * different meanings to the same identifier. + */ +int __init usb_string_id(struct usb_composite_dev *cdev) +{ + if (cdev->next_string_id < 254) { + /* string id 0 is reserved */ + cdev->next_string_id++; + return cdev->next_string_id; + } + return -ENODEV; +} + +/*-------------------------------------------------------------------------*/ + +static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req) +{ + if (req->status || req->actual != req->length) + DBG((struct usb_composite_dev *) ep->driver_data, + "setup complete --> %d, %d/%d\n", + req->status, req->actual, req->length); +} + +/* + * The setup() callback implements all the ep0 functionality that's + * not handled lower down, in hardware or the hardware driver(like + * device and endpoint feature flags, and their status). It's all + * housekeeping for the gadget function we're implementing. Most of + * the work is in config and function specific setup. + */ +static int +composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl) +{ + struct usb_composite_dev *cdev = get_gadget_data(gadget); + struct usb_request *req = cdev->req; + int value = -EOPNOTSUPP; + u16 w_index = le16_to_cpu(ctrl->wIndex); + u16 w_value = le16_to_cpu(ctrl->wValue); + u16 w_length = le16_to_cpu(ctrl->wLength); + struct usb_function *f = NULL; + + /* partial re-init of the response message; the function or the + * gadget might need to intercept e.g. a control-OUT completion + * when we delegate to it. + */ + req->zero = 0; + req->complete = composite_setup_complete; + req->length = USB_BUFSIZ; + gadget->ep0->driver_data = cdev; + + switch (ctrl->bRequest) { + + /* we handle all standard USB descriptors */ + case USB_REQ_GET_DESCRIPTOR: + if (ctrl->bRequestType != USB_DIR_IN) + goto unknown; + switch (w_value >> 8) { + + case USB_DT_DEVICE: + cdev->desc.bNumConfigurations = + count_configs(cdev, USB_DT_DEVICE); + value = min(w_length, (u16) sizeof cdev->desc); + memcpy(req->buf, &cdev->desc, value); + break; + case USB_DT_DEVICE_QUALIFIER: + if (!gadget_is_dualspeed(gadget)) + break; + device_qual(cdev); + value = min_t(int, w_length, + sizeof(struct usb_qualifier_descriptor)); + break; + case USB_DT_OTHER_SPEED_CONFIG: + if (!gadget_is_dualspeed(gadget)) + break; + /* FALLTHROUGH */ + case USB_DT_CONFIG: + value = config_desc(cdev, w_value); + if (value >= 0) + value = min(w_length, (u16) value); + break; + case USB_DT_STRING: + value = get_string(cdev, req->buf, + w_index, w_value & 0xff); + if (value >= 0) + value = min(w_length, (u16) value); + break; + } + break; + + /* any number of configs can work */ + case USB_REQ_SET_CONFIGURATION: + if (ctrl->bRequestType != 0) + goto unknown; + if (gadget_is_otg(gadget)) { + if (gadget->a_hnp_support) + DBG(cdev, "HNP available\n"); + else if (gadget->a_alt_hnp_support) + DBG(cdev, "HNP on another port\n"); + else + VDBG(cdev, "HNP inactive\n"); + } + spin_lock(&cdev->lock); + value = set_config(cdev, ctrl, w_value); + spin_unlock(&cdev->lock); + break; + case USB_REQ_GET_CONFIGURATION: + if (ctrl->bRequestType != USB_DIR_IN) + goto unknown; + if (cdev->config) + *(u8 *)req->buf = cdev->config->bConfigurationValue; + else + *(u8 *)req->buf = 0; + value = min(w_length, (u16) 1); + break; + + /* function drivers must handle get/set altsetting; if there's + * no get() method, we know only altsetting zero works. + */ + case USB_REQ_SET_INTERFACE: + if (ctrl->bRequestType != USB_RECIP_INTERFACE) + goto unknown; + if (!cdev->config || w_index >= MAX_CONFIG_INTERFACES) + break; + f = cdev->config->interface[w_index]; + if (!f) + break; + if (w_value && !f->get_alt) + break; + value = f->set_alt(f, w_index, w_value); + break; + case USB_REQ_GET_INTERFACE: + if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE)) + goto unknown; + if (!cdev->config || w_index >= MAX_CONFIG_INTERFACES) + break; + f = cdev->config->interface[w_index]; + if (!f) + break; + /* lots of interfaces only need altsetting zero... */ + value = f->get_alt ? f->get_alt(f, w_index) : 0; + if (value < 0) + break; + *((u8 *)req->buf) = value; + value = min(w_length, (u16) 1); + break; + default: +unknown: + VDBG(cdev, + "non-core control req%02x.%02x v%04x i%04x l%d\n", + ctrl->bRequestType, ctrl->bRequest, + w_value, w_index, w_length); + + /* functions always handle their interfaces ... punt other + * recipients (endpoint, other, WUSB, ...) to the current + * configuration code. + * + * REVISIT it could make sense to let the composite device + * take such requests too, if that's ever needed: to work + * in config 0, etc. + */ + if ((ctrl->bRequestType & USB_RECIP_MASK) + == USB_RECIP_INTERFACE) { + f = cdev->config->interface[w_index]; + if (f && f->setup) + value = f->setup(f, ctrl); + else + f = NULL; + } + if (value < 0 && !f) { + struct usb_configuration *c; + + c = cdev->config; + if (c && c->setup) + value = c->setup(c, ctrl); + } + + goto done; + } + + /* respond with data transfer before status phase? */ + if (value >= 0) { + req->length = value; + req->zero = value < w_length; + value = usb_ep_queue(gadget->ep0, req, GFP_ATOMIC); + if (value < 0) { + DBG(cdev, "ep_queue --> %d\n", value); + req->status = 0; + composite_setup_complete(gadget->ep0, req); + } + } + +done: + /* device either stalls (value < 0) or reports success */ + return value; +} + +static void composite_disconnect(struct usb_gadget *gadget) +{ + struct usb_composite_dev *cdev = get_gadget_data(gadget); + unsigned long flags; + + /* REVISIT: should we have config and device level + * disconnect callbacks? + */ + spin_lock_irqsave(&cdev->lock, flags); + if (cdev->config) + reset_config(cdev); + spin_unlock_irqrestore(&cdev->lock, flags); +} + +/*-------------------------------------------------------------------------*/ + +static void /* __init_or_exit */ +composite_unbind(struct usb_gadget *gadget) +{ + struct usb_composite_dev *cdev = get_gadget_data(gadget); + + /* composite_disconnect() must already have been called + * by the underlying peripheral controller driver! + * so there's no i/o concurrency that could affect the + * state protected by cdev->lock. + */ + WARN_ON(cdev->config); + + while (!list_empty(&cdev->configs)) { + struct usb_configuration *c; + + c = list_first_entry(&cdev->configs, + struct usb_configuration, list); + while (!list_empty(&c->functions)) { + struct usb_function *f; + + f = list_first_entry(&c->functions, + struct usb_function, list); + list_del(&f->list); + if (f->unbind) { + DBG(cdev, "unbind function '%s'/%p\n", + f->name, f); + f->unbind(c, f); + /* may free memory for "f" */ + } + } + list_del(&c->list); + if (c->unbind) { + DBG(cdev, "unbind config '%s'/%p\n", c->label, c); + c->unbind(c); + /* may free memory for "c" */ + } + } + if (composite->unbind) + composite->unbind(cdev); + + if (cdev->req) { + kfree(cdev->req->buf); + usb_ep_free_request(gadget->ep0, cdev->req); + } + kfree(cdev); + set_gadget_data(gadget, NULL); + composite = NULL; +} + +static void __init +string_override_one(struct usb_gadget_strings *tab, u8 id, const char *s) +{ + struct usb_string *str = tab->strings; + + for (str = tab->strings; str->s; str++) { + if (str->id == id) { + str->s = s; + return; + } + } +} + +static void __init +string_override(struct usb_gadget_strings **tab, u8 id, const char *s) +{ + while (*tab) { + string_override_one(*tab, id, s); + tab++; + } +} + +static int __init composite_bind(struct usb_gadget *gadget) +{ + struct usb_composite_dev *cdev; + int status = -ENOMEM; + + cdev = kzalloc(sizeof *cdev, GFP_KERNEL); + if (!cdev) + return status; + + spin_lock_init(&cdev->lock); + cdev->gadget = gadget; + set_gadget_data(gadget, cdev); + INIT_LIST_HEAD(&cdev->configs); + + /* preallocate control response and buffer */ + cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL); + if (!cdev->req) + goto fail; + cdev->req->buf = kmalloc(USB_BUFSIZ, GFP_KERNEL); + if (!cdev->req->buf) + goto fail; + cdev->req->complete = composite_setup_complete; + gadget->ep0->driver_data = cdev; + + cdev->bufsiz = USB_BUFSIZ; + cdev->driver = composite; + + usb_gadget_set_selfpowered(gadget); + + /* interface and string IDs start at zero via kzalloc. + * we force endpoints to start unassigned; few controller + * drivers will zero ep->driver_data. + */ + usb_ep_autoconfig_reset(cdev->gadget); + + /* composite gadget needs to assign strings for whole device (like + * serial number), register function drivers, potentially update + * power state and consumption, etc + */ + status = composite->bind(cdev); + if (status < 0) + goto fail; + + cdev->desc = *composite->dev; + cdev->desc.bMaxPacketSize0 = gadget->ep0->maxpacket; + + /* standardized runtime overrides for device ID data */ + if (idVendor) + cdev->desc.idVendor = cpu_to_le16(idVendor); + if (idProduct) + cdev->desc.idProduct = cpu_to_le16(idProduct); + if (bcdDevice) + cdev->desc.bcdDevice = cpu_to_le16(bcdDevice); + + /* strings can't be assigned before bind() allocates the + * releavnt identifiers + */ + if (cdev->desc.iManufacturer && iManufacturer) + string_override(composite->strings, + cdev->desc.iManufacturer, iManufacturer); + if (cdev->desc.iProduct && iProduct) + string_override(composite->strings, + cdev->desc.iProduct, iProduct); + if (cdev->desc.iSerialNumber && iSerialNumber) + string_override(composite->strings, + cdev->desc.iSerialNumber, iSerialNumber); + + INFO(cdev, "%s ready\n", composite->name); + return 0; + +fail: + composite_unbind(gadget); + return status; +} + +/*-------------------------------------------------------------------------*/ + +static void +composite_suspend(struct usb_gadget *gadget) +{ + struct usb_composite_dev *cdev = get_gadget_data(gadget); + struct usb_function *f; + + /* REVISIT: should we have config and device level + * suspend/resume callbacks? + */ + DBG(cdev, "suspend\n"); + if (cdev->config) { + list_for_each_entry(f, &cdev->config->functions, list) { + if (f->suspend) + f->suspend(f); + } + } +} + +static void +composite_resume(struct usb_gadget *gadget) +{ + struct usb_composite_dev *cdev = get_gadget_data(gadget); + struct usb_function *f; + + /* REVISIT: should we have config and device level + * suspend/resume callbacks? + */ + DBG(cdev, "resume\n"); + if (cdev->config) { + list_for_each_entry(f, &cdev->config->functions, list) { + if (f->resume) + f->resume(f); + } + } +} + +/*-------------------------------------------------------------------------*/ + +static struct usb_gadget_driver composite_driver = { + .speed = USB_SPEED_HIGH, + + .bind = composite_bind, + .unbind = __exit_p(composite_unbind), + + .setup = composite_setup, + .disconnect = composite_disconnect, + + .suspend = composite_suspend, + .resume = composite_resume, + + .driver = { + .owner = THIS_MODULE, + }, +}; + +/** + * usb_composite_register() - register a composite driver + * @driver: the driver to register + * Context: single threaded during gadget setup + * + * This function is used to register drivers using the composite driver + * framework. The return value is zero, or a negative errno value. + * Those values normally come from the driver's @bind method, which does + * all the work of setting up the driver to match the hardware. + * + * On successful return, the gadget is ready to respond to requests from + * the host, unless one of its components invokes usb_gadget_disconnect() + * while it was binding. That would usually be done in order to wait for + * some userspace participation. + */ +int __init usb_composite_register(struct usb_composite_driver *driver) +{ + if (!driver || !driver->dev || !driver->bind || composite) + return -EINVAL; + + if (!driver->name) + driver->name = "composite"; + composite_driver.function = (char *) driver->name; + composite_driver.driver.name = driver->name; + composite = driver; + + return usb_gadget_register_driver(&composite_driver); +} + +/** + * usb_composite_unregister() - unregister a composite driver + * @driver: the driver to unregister + * + * This function is used to unregister drivers using the composite + * driver framework. + */ +void __exit usb_composite_unregister(struct usb_composite_driver *driver) +{ + if (composite != driver) + return; + usb_gadget_unregister_driver(&composite_driver); +} |