blob: 5106cc56cb6f59b76835fee903fd0cc32109e14a [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* composite.c - infrastructure for Composite USB Gadgets
*
* Copyright (C) 2006-2008 David Brownell
* U-Boot porting: Lukasz Majewski <l.majewski@samsung.com>
*/
#undef DEBUG
#include <linux/bitops.h>
#include <linux/usb/composite.h>
#define USB_BUFSIZ 4096
static struct usb_composite_driver *composite;
/**
* 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 usb_add_function(struct usb_configuration *config,
struct usb_function *function)
{
int value = -EINVAL;
debug("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);
if (function->bind) {
value = function->bind(config, function);
if (value < 0) {
list_del(&function->list);
function->config = NULL;
}
} else
value = 0;
if (!config->fullspeed && function->descriptors)
config->fullspeed = 1;
if (!config->highspeed && function->hs_descriptors)
config->highspeed = 1;
done:
if (value)
debug("adding '%s'/%p --> %d\n",
function->name, function, value);
return value;
}
/**
* usb_function_deactivate - prevent function and gadget enumeration
* @function: the function that isn't yet ready to respond
*
* Blocks response of the gadget driver to host enumeration by
* preventing the data line pullup from being activated. This is
* normally called during @bind() processing to change from the
* initial "ready to respond" state, or when a required resource
* becomes available.
*
* For example, drivers that serve as a passthrough to a userspace
* daemon can block enumeration unless that daemon (such as an OBEX,
* MTP, or print server) is ready to handle host requests.
*
* Not all systems support software control of their USB peripheral
* data pullups.
*
* Returns zero on success, else negative errno.
*/
int usb_function_deactivate(struct usb_function *function)
{
struct usb_composite_dev *cdev = function->config->cdev;
int status = 0;
if (cdev->deactivations == 0)
status = usb_gadget_disconnect(cdev->gadget);
if (status == 0)
cdev->deactivations++;
return status;
}
/**
* usb_function_activate - allow function and gadget enumeration
* @function: function on which usb_function_activate() was called
*
* Reverses effect of usb_function_deactivate(). If no more functions
* are delaying their activation, the gadget driver will respond to
* host enumeration procedures.
*
* Returns zero on success, else negative errno.
*/
int usb_function_activate(struct usb_function *function)
{
struct usb_composite_dev *cdev = function->config->cdev;
int status = 0;
if (cdev->deactivations == 0)
status = -EINVAL;
else {
cdev->deactivations--;
if (cdev->deactivations == 0)
status = usb_gadget_connect(cdev->gadget);
}
return status;
}
/**
* 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 usb_interface_id(struct usb_configuration *config,
struct usb_function *function)
{
unsigned char 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)
{
int len = USB_BUFSIZ - USB_DT_CONFIG_SIZE;
void *next = buf + USB_DT_CONFIG_SIZE;
struct usb_descriptor_header **descriptors;
struct usb_config_descriptor *c;
int status;
struct usb_function *f;
/* write the config descriptor */
c = buf;
c->bLength = USB_DT_CONFIG_SIZE;
c->bDescriptorType = type;
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 ? : (CONFIG_USB_GADGET_VBUS_DRAW / 2);
/* 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) {
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)
{
enum usb_device_speed speed = USB_SPEED_UNKNOWN;
struct usb_gadget *gadget = cdev->gadget;
u8 type = w_value >> 8;
int hs = 0;
struct usb_configuration *c;
if (gadget_is_dualspeed(gadget)) {
if (gadget->speed == USB_SPEED_HIGH)
hs = 1;
if (type == USB_DT_OTHER_SPEED_CONFIG)
hs = !hs;
if (hs)
speed = USB_SPEED_HIGH;
}
w_value &= 0xff;
list_for_each_entry(c, &cdev->configs, list) {
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;
unsigned count = 0;
int hs = 0;
struct usb_configuration *c;
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->gadget->ep0->maxpacket;
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;
debug("%s:\n", __func__);
list_for_each_entry(f, &cdev->config->functions, list) {
if (f->disable)
f->disable(f);
bitmap_zero(f->endpoints, 32);
}
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;
unsigned power = gadget_is_otg(gadget) ? 8 : 100;
struct usb_descriptor_header **descriptors;
int result = -EINVAL;
struct usb_endpoint_descriptor *ep;
struct usb_configuration *c = NULL;
int addr;
int tmp;
struct usb_function *f;
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;
debug("%s: %s speed config #%d: %s\n", __func__,
({ 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++) {
f = c->interface[tmp];
if (!f)
break;
/*
* Record which endpoints are used by the function. This is used
* to dispatch control requests targeted at that endpoint to the
* function's setup callback instead of the current
* configuration's setup callback.
*/
if (gadget->speed == USB_SPEED_HIGH)
descriptors = f->hs_descriptors;
else
descriptors = f->descriptors;
for (; *descriptors; ++descriptors) {
if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
continue;
ep = (struct usb_endpoint_descriptor *)*descriptors;
addr = ((ep->bEndpointAddress & 0x80) >> 3)
| (ep->bEndpointAddress & 0x0f);
generic_set_bit(addr, f->endpoints);
}
result = f->set_alt(f, tmp, 0);
if (result < 0) {
debug("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 = c->bMaxPower ? (2 * c->bMaxPower) : CONFIG_USB_GADGET_VBUS_DRAW;
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 usb_add_config(struct usb_composite_dev *cdev,
struct usb_configuration *config)
{
int status = -EINVAL;
struct usb_configuration *c;
struct usb_function *f;
unsigned int i;
debug("%s: adding config #%u '%s'/%p\n", __func__,
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 {
debug("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++) {
f = config->interface[i];
if (!f)
continue;
debug("%s: interface %d = %s/%p\n",
__func__, i, f->name, f);
}
}
usb_ep_autoconfig_reset(cdev->gadget);
done:
if (status)
debug("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
)
{
int value;
struct usb_gadget_strings *s;
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_string_descriptor *s = buf;
struct usb_gadget_strings **sp;
int len;
struct usb_configuration *c;
struct usb_function *f;
/*
* 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) {
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; len <= 126 && s->wData[len]; 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,
* @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
* that for example different functions don't wrongly assign different
* meanings to the same identifier.
*/
int usb_string_id(struct usb_composite_dev *cdev)
{
if (cdev->next_string_id < 254) {
/*
* string id 0 is reserved by USB spec for list of
* supported languages
* 255 reserved as well? -- mina86
*/
cdev->next_string_id++;
return cdev->next_string_id;
}
return -ENODEV;
}
/**
* usb_string_ids() - allocate unused string IDs in batch
* @cdev: the device whose string descriptor IDs are being allocated
* @str: an array of usb_string objects to assign numbers to
* Context: single threaded during gadget setup
*
* @usb_string_ids() is called from bind() callbacks to allocate
* string IDs. Drivers for functions, configurations, or gadgets will
* then copy IDs from the string table to the appropriate descriptors
* and string table for other languages.
*
* All string identifier should be allocated using this,
* @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
* example different functions don't wrongly assign different meanings
* to the same identifier.
*/
int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
{
u8 next = cdev->next_string_id;
for (; str->s; ++str) {
if (next >= 254)
return -ENODEV;
str->id = ++next;
}
cdev->next_string_id = next;
return 0;
}
/**
* usb_string_ids_n() - allocate unused string IDs in batch
* @c: the device whose string descriptor IDs are being allocated
* @n: number of string IDs to allocate
* Context: single threaded during gadget setup
*
* Returns the first requested ID. This ID and next @n-1 IDs are now
* valid IDs. At least provided that @n is non-zero because if it
* is, returns last requested ID which is now very useful information.
*
* @usb_string_ids_n() 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,
* @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
* example different functions don't wrongly assign different meanings
* to the same identifier.
*/
int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
{
u8 next = c->next_string_id;
if (n > 254 || next + n > 254)
return -ENODEV;
c->next_string_id += n;
return next + 1;
}
static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
{
if (req->status || req->actual != req->length)
debug("%s: setup complete --> %d, %d/%d\n", __func__,
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)
{
u16 w_length = le16_to_cpu(ctrl->wLength);
u16 w_index = le16_to_cpu(ctrl->wIndex);
u16 w_value = le16_to_cpu(ctrl->wValue);
struct usb_composite_dev *cdev = get_gadget_data(gadget);
u8 intf = w_index & 0xFF;
int value = -EOPNOTSUPP;
struct usb_request *req = cdev->req;
struct usb_function *f = NULL;
int standard;
u8 endp;
struct usb_configuration *c;
/*
* 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;
standard = (ctrl->bRequestType & USB_TYPE_MASK)
== USB_TYPE_STANDARD;
if (!standard)
goto unknown;
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);
cdev->desc.bMaxPacketSize0 =
cdev->gadget->ep0->maxpacket;
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;
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;
case USB_DT_BOS:
/*
* The USB compliance test (USB 2.0 Command Verifier)
* issues this request. We should not run into the
* default path here. But return for now until
* the superspeed support is added.
*/
break;
default:
goto unknown;
}
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)
debug("HNP available\n");
else if (gadget->a_alt_hnp_support)
debug("HNP on another port\n");
else
debug("HNP inactive\n");
}
value = set_config(cdev, ctrl, w_value);
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[intf];
if (!f)
break;
if (w_value && !f->set_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[intf];
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:
debug("non-core control req%02x.%02x v%04x i%04x l%d\n",
ctrl->bRequestType, ctrl->bRequest,
w_value, w_index, w_length);
if (!cdev->config)
goto done;
/*
* functions always handle their interfaces and endpoints...
* punt other recipients (other, WUSB, ...) to the current
* configuration code.
*/
switch (ctrl->bRequestType & USB_RECIP_MASK) {
case USB_RECIP_INTERFACE:
f = cdev->config->interface[intf];
break;
case USB_RECIP_ENDPOINT:
endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
list_for_each_entry(f, &cdev->config->functions, list) {
if (test_bit(endp, f->endpoints))
break;
}
if (&f->list == &cdev->config->functions)
f = NULL;
break;
/*
* dfu-util (version 0.5) sets bmRequestType.Receipent = Device
* for non-standard request (w_value = 0x21,
* bRequest = GET_DESCRIPTOR in this case).
* When only one interface is registered (as it is done now),
* then this request shall be handled as it was requested for
* interface.
*
* In the below code it is checked if only one interface is
* present and proper function for it is extracted. Due to that
* function's setup (f->setup) is called to handle this
* special non-standard request.
*/
case USB_RECIP_DEVICE:
debug("cdev->config->next_interface_id: %d intf: %d\n",
cdev->config->next_interface_id, intf);
if (cdev->config->next_interface_id == 1)
f = cdev->config->interface[intf];
break;
}
if (f && f->setup)
value = f->setup(f, ctrl);
else {
c = cdev->config;
if (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_KERNEL);
if (value < 0) {
debug("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);
if (cdev->config)
reset_config(cdev);
if (composite->disconnect)
composite->disconnect(cdev);
}
static void composite_unbind(struct usb_gadget *gadget)
{
struct usb_composite_dev *cdev = get_gadget_data(gadget);
struct usb_configuration *c;
struct usb_function *f;
/*
* 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.
*/
BUG_ON(cdev->config);
while (!list_empty(&cdev->configs)) {
c = list_first_entry(&cdev->configs,
struct usb_configuration, list);
while (!list_empty(&c->functions)) {
f = list_first_entry(&c->functions,
struct usb_function, list);
list_del(&f->list);
if (f->unbind) {
debug("unbind function '%s'/%p\n",
f->name, f);
f->unbind(c, f);
}
}
list_del(&c->list);
if (c->unbind) {
debug("unbind config '%s'/%p\n", c->label, c);
c->unbind(c);
}
free(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 int composite_bind(struct usb_gadget *gadget)
{
int status = -ENOMEM;
struct usb_composite_dev *cdev;
cdev = calloc(sizeof *cdev, 1);
if (!cdev)
return status;
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 = memalign(CONFIG_SYS_CACHELINE_SIZE, USB_BUFSIZ);
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);
usb_ep_autoconfig_reset(cdev->gadget);
status = composite->bind(cdev);
if (status < 0)
goto fail;
memcpy(&cdev->desc, composite->dev,
sizeof(struct usb_device_descriptor));
cdev->desc.bMaxPacketSize0 = gadget->ep0->maxpacket;
debug("%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;
debug("%s: suspend\n", __func__);
if (cdev->config) {
list_for_each_entry(f, &cdev->config->functions, list) {
if (f->suspend)
f->suspend(f);
}
}
if (composite->suspend)
composite->suspend(cdev);
cdev->suspended = 1;
}
static void
composite_resume(struct usb_gadget *gadget)
{
struct usb_composite_dev *cdev = get_gadget_data(gadget);
struct usb_function *f;
debug("%s: resume\n", __func__);
if (composite->resume)
composite->resume(cdev);
if (cdev->config) {
list_for_each_entry(f, &cdev->config->functions, list) {
if (f->resume)
f->resume(f);
}
}
cdev->suspended = 0;
}
static struct usb_gadget_driver composite_driver = {
.speed = USB_SPEED_HIGH,
.bind = composite_bind,
.unbind = composite_unbind,
.setup = composite_setup,
.reset = composite_disconnect,
.disconnect = composite_disconnect,
.suspend = composite_suspend,
.resume = composite_resume,
};
/**
* 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 usb_composite_register(struct usb_composite_driver *driver)
{
int res;
if (!driver || !driver->dev || !driver->bind || composite)
return -EINVAL;
if (!driver->name)
driver->name = "composite";
composite = driver;
res = usb_gadget_register_driver(&composite_driver);
if (res != 0)
composite = NULL;
return res;
}
/**
* 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 usb_composite_unregister(struct usb_composite_driver *driver)
{
if (composite != driver)
return;
usb_gadget_unregister_driver(&composite_driver);
composite = NULL;
}