// SPDX-License-Identifier: GPL-2.0
/**
* udc.c - Core UDC Framework
*
* Copyright (C) 2010 Texas Instruments
* Author: Felipe Balbi <balbi@ti.com>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/list.h>
#include <linux/err.h>
#include <linux/dma-mapping.h>
#include <linux/sched/task_stack.h>
#include <linux/workqueue.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
#include <linux/usb.h>
#include "trace.h"
/**
* struct usb_udc - describes one usb device controller
* @driver - the gadget driver pointer. For use by the class code
* @dev - the child device to the actual controller
* @gadget - the gadget. For use by the class code
* @list - for use by the udc class driver
* @vbus - for udcs who care about vbus status, this value is real vbus status;
* for udcs who do not care about vbus status, this value is always true
*
* This represents the internal data structure which is used by the UDC-class
* to hold information about udc driver and gadget together.
*/
struct usb_udc {
struct usb_gadget_driver *driver;
struct usb_gadget *gadget;
struct device dev;
struct list_head list;
bool vbus;
};
static struct class *udc_class;
static LIST_HEAD(udc_list);
static LIST_HEAD(gadget_driver_pending_list);
static DEFINE_MUTEX(udc_lock);
static int udc_bind_to_driver(struct usb_udc *udc,
struct usb_gadget_driver *driver);
/* ------------------------------------------------------------------------- */
/**
* usb_ep_set_maxpacket_limit - set maximum packet size limit for endpoint
* @ep:the endpoint being configured
* @maxpacket_limit:value of maximum packet size limit
*
* This function should be used only in UDC drivers to initialize endpoint
* (usually in probe function).
*/
void usb_ep_set_maxpacket_limit(struct usb_ep *ep,
unsigned maxpacket_limit)
{
ep->maxpacket_limit = maxpacket_limit;
ep->maxpacket = maxpacket_limit;
trace_usb_ep_set_maxpacket_limit(ep, 0);
}
EXPORT_SYMBOL_GPL(usb_ep_set_maxpacket_limit);
/**
* usb_ep_enable - configure endpoint, making it usable
* @ep:the endpoint being configured. may not be the endpoint named "ep0".
* drivers discover endpoints through the ep_list of a usb_gadget.
*
* When configurations are set, or when interface settings change, the driver
* will enable or disable the relevant endpoints. while it is enabled, an
* endpoint may be used for i/o until the driver receives a disconnect() from
* the host or until the endpoint is disabled.
*
* the ep0 implementation (which calls this routine) must ensure that the
* hardware capabilities of each endpoint match the descriptor provided
* for it. for example, an endpoint named "ep2in-bulk" would be usable
* for interrupt transfers as well as bulk, but it likely couldn't be used
* for iso transfers or for endpoint 14. some endpoints are fully
* configurable, with more generic names like "ep-a". (remember that for
* USB, "in" means "towards the USB master".)
*
* This routine must be called in process context.
*
* returns zero, or a negative error code.
*/
int usb_ep_enable(struct usb_ep *ep)
{
int ret = 0;
if (ep->enabled)
goto out;
ret = ep->ops->enable(ep, ep->desc);
if (ret)
goto out;
ep->enabled = true;
out:
trace_usb_ep_enable(ep, ret);
return ret;
}
EXPORT_SYMBOL_GPL(usb_ep_enable);
/**
* usb_ep_disable - endpoint is no longer usable
* @ep:the endpoint being unconfigured. may not be the endpoint named "ep0".
*
* no other task may be using this endpoint when this is called.
* any pending and uncompleted requests will complete with status
* indicating disconnect (-ESHUTDOWN) before this call returns.
* gadget drivers must call usb_ep_enable() again before queueing
* requests to the endpoint.
*
* This routine must be called in process context.
*
* returns zero, or a negative error code.
*/
int usb_ep_disable(struct usb_ep *ep)
{
int ret = 0;
if (!ep->enabled)
goto out;
ret = ep->ops->disable(ep);
if (ret)
goto out;
ep->enabled = false;
out:
trace_usb_ep_disable(ep, ret);
return ret;
}
EXPORT_SYMBOL_GPL(usb_ep_disable);
/**
* usb_ep_alloc_request - allocate a request object to use with this endpoint
* @ep:the endpoint to be used with with the request
* @gfp_flags:GFP_* flags to use
*
* Request objects must be allocated with this call, since they normally
* need controller-specific setup and may even need endpoint-specific
* resources such as allocation of DMA descriptors.
* Requests may be submitted with usb_ep_queue(), and receive a single
* completion callback. Free requests with usb_ep_free_request(), when
* they are no longer needed.
*
* Returns the request, or null if one could not be allocated.
*/
struct usb_request *usb_ep_alloc_request(struct usb_ep *ep,
gfp_t gfp_flags)
{
struct usb_request *req = NULL;
req = ep->ops->alloc_request(ep, gfp_flags);
trace_usb_ep_alloc_request(ep, req, req ? 0 : -ENOMEM);
return req;
}
EXPORT_SYMBOL_GPL(usb_ep_alloc_request);
/**
* usb_ep_free_request - frees a request object
* @ep:the endpoint associated with the request
* @req:the request being freed
*
* Reverses the effect of usb_ep_alloc_request().
* Caller guarantees the request is not queued, and that it will
* no longer be requeued (or otherwise used).
*/
void usb_ep_free_request(struct usb_ep *ep,
struct usb_request *req)
{
trace_usb_ep_free_request(ep, req, 0);
ep->ops->free_request(ep, req);
}
EXPORT_SYMBOL_GPL(usb_ep_free_request);
/**
* usb_ep_queue - queues (submits) an I/O request to an endpoint.
* @ep:the endpoint associated with the request
* @req:the request being submitted
* @gfp_flags: GFP_* flags to use in case the lower level driver couldn't
* pre-allocate all necessary memory with the request.
*
* This tells the device controller to perform the specified request through
* that endpoint (reading or writing a buffer). When the request completes,
* including being canceled by usb_ep_dequeue(), the request's completion
* routine is called to return the request to the driver. Any endpoint
* (except control endpoints like ep0) may have more than one transfer
* request queued; they complete in FIFO order. Once a gadget driver
* submits a request, that request may not be examined or modified until it
* is given back to that driver through the completion callback.
*
* Each request is turned into one or more packets. The controller driver
* never merges adjacent requests into the same packet. OUT transfers
* will sometimes use data that's already buffered in the hardware.
* Drivers can rely on the fact that the first byte of the request's buffer
* always corresponds to the first byte of some USB packet, for both
* IN and OUT transfers.
*
* Bulk endpoints can queue any amount of data; the transfer is packetized
* automatically. The last packet will be short if the request doesn't fill it
* out completely. Zero length packets (ZLPs) should be avoided in portable
* protocols since not all usb hardware can successfully handle zero length
* packets. (ZLPs may be explicitly written, and may be implicitly written if
* the request 'zero' flag is set.) Bulk endpoints may also be used
* for interrupt transfers; but the reverse is not true, and some endpoints
* won't support every interrupt transfer. (Such as 768 byte packets.)
*
* Interrupt-only endpoints are less functional than bulk endpoints, for
* example by not supporting queueing or not handling buffers that are
* larger than the endpoint's maxpacket size. They may also treat data
* toggle differently.
*
* Control endpoints ... after getting a setup() callback, the driver queues
* one response (even if it would be zero length). That enables the
* status ack, after transferring data as specified in the response. Setup
* functions may return negative error codes to generate protocol stalls.
* (Note that some USB device controllers disallow protocol stall responses
* in some cases.) When control responses are deferred (the response is
* written after the setup callback returns), then usb_ep_set_halt() may be
* used on ep0 to trigger protocol stalls. Depending on the controller,
* it may not be possible to trigger a status-stage protocol stall when the
* data stage is over, that is, from within the response's completion
* routine.
*
* For periodic endpoints, like interrupt or isochronous ones, the usb host
* arranges to poll once per interval, and the gadget driver usually will
* have queued some data to transfer at that time.
*
* Note that @req's ->complete() callback must never be called from
* within usb_ep_queue() as that can create deadlock situations.
*
* This routine may be called in interrupt context.
*
* Returns zero, or a negative error code. Endpoints that are not enabled
* report errors; errors will also be
* reported when the usb peripheral is disconnected.
*
* If and only if @req is successfully queued (the return value is zero),
* @req->complete() will be called exactly once, when the Gadget core and
* UDC are finished with the request. When the completion function is called,
* control of the request is returned to the device driver which submitted it.
* The completion handler may then immediately free or reuse @req.
*/
int usb_ep_queue(struct usb_ep *ep,
struct usb_request *req, gfp_t gfp_flags)
{
int ret = 0;
if (WARN_ON_ONCE(!ep->enabled && ep->address)) {
ret = -ESHUTDOWN;
goto out;
}
ret = ep->ops->queue(ep, req, gfp_flags);
out:
trace_usb_ep_queue(ep, req, ret);
return ret;
}
EXPORT_SYMBOL_GPL(usb_ep_queue);
/**
* usb_ep_dequeue - dequeues (cancels, unlinks) an I/O request from an endpoint
* @ep:the endpoint associated with the request
* @req:the request being canceled
*
* If the request is still active on the endpoint, it is dequeued and
* eventually its completion routine is called (with status -ECONNRESET);
* else a negative error code is returned. This routine is asynchronous,
* that is, it may return before the completion routine runs.
*
* Note that some hardware can't clear out write fifos (to unlink the request
* at the head of the queue) except as part of disconnecting from usb. Such
* restrictions prevent drivers from supporting configuration changes,
* even to configuration zero (a "chapter 9" requirement).
*
* This routine may be called in interrupt context.
*/
int usb_ep_dequeue(struct usb_ep *ep, struct usb_request *req)
{
int ret;
ret = ep->ops->dequeue(ep, req);
trace_usb_ep_dequeue(ep, req, ret);
return ret;
}
EXPORT_SYMBOL_GPL(usb_ep_dequeue);
/**
* usb_ep_set_halt - sets the endpoint halt feature.
* @ep: the non-isochronous endpoint being stalled
*
* Use this to stall an endpoint, perhaps as an error report.
* Except for control endpoints,
* the endpoint stays halted (will not stream any data) until the host
* clears this feature; drivers may need to empty the endpoint's request
* queue first, to make sure no inappropriate transfers happen.
*
* Note that while an endpoint CLEAR_FEATURE will be invisible to the
* gadget driver, a SET_INTERFACE will not be. To reset endpoints for the
* current altsetting, see usb_ep_clear_halt(). When switching altsettings,
* it's simplest to use usb_ep_enable() or usb_ep_disable() for the endpoints.
*
* This routine may be called in interrupt context.
*
* Returns zero, or a negative error code. On success, this call sets
* underlying hardware state that blocks data transfers.
* Attempts to halt IN endpoints will fail (returning -EAGAIN) if any
* transfer requests are still queued, or if the controller hardware
* (usually a FIFO) still holds bytes that the host hasn't collected.
*/
int usb_ep_set_halt(struct usb_ep *ep)
{
int ret;
ret = ep->ops->set_halt(ep, 1);
trace_usb_ep_set_halt(ep, ret);
return ret;
}
EXPORT_SYMBOL_GPL(usb_ep_set_halt);
/**
* usb_ep_clear_halt - clears endpoint halt, and resets toggle
* @ep:the bulk or interrupt endpoint being reset
*
* Use this when responding to the standard usb "set interface" request,
* for endpoints that aren't reconfigured, after clearing any other state
* in the endpoint's i/o queue.
*
* This routine may be called in interrupt context.
*
* Returns zero, or a negative error code. On success, this call clears
* the underlying hardware state reflecting endpoint halt and data toggle.
* Note that some hardware can't support this request (like pxa2xx_udc),
* and accordingly can't correctly implement interface altsettings.
*/
int usb_ep_clear_halt(struct usb_ep *ep)
{
int ret;
ret = ep->ops->set_halt(ep, 0);
trace_usb_ep_clear_halt(ep, ret);
return ret;
}
EXPORT_SYMBOL_GPL(usb_ep_clear_halt);
/**
* usb_ep_set_wedge - sets the halt feature and ignores clear requests
* @ep: the endpoint being wedged
*
* Use this to stall an endpoint and ignore CLEAR_FEATURE(HALT_ENDPOINT)
* requests. If the gadget driver clears the halt status, it will
* automatically unwedge the endpoint.
*
* This routine may be called in interrupt context.
*
* Returns zero on success, else negative errno.
*/
int usb_ep_set_wedge(struct usb_ep *ep)
{
int ret;
if (ep->ops->set_wedge)
ret = ep->ops->set_wedge(ep);
else
ret = ep->ops->set_halt(ep, 1);
trace_usb_ep_set_wedge(ep, ret);
return ret;
}
EXPORT_SYMBOL_GPL(usb_ep_set_wedge);
/**
* usb_ep_fifo_status - returns number of bytes in fifo, or error
* @ep: the endpoint whose fifo status is being checked.
*
* FIFO endpoints may have "unclaimed data" in them in certain cases,
* such as after aborted transfers. Hosts may not have collected all
* the IN data written by the gadget driver (and reported by a request
* completion). The gadget driver may not have collected all the data
* written OUT to it by the host. Drivers that need precise handling for
* fault reporting or recovery may need to use this call.
*
* This routine may be called in interrupt context.
*
* This returns the number of such bytes in the fifo, or a negative
* errno if the endpoint doesn't use a FIFO or doesn't support such
* precise handling.
*/
int usb_ep_fifo_status(struct usb_ep *ep)
{
int ret;
if (ep->ops->fifo_status)
ret = ep->ops->fifo_status(ep);
else
ret = -EOPNOTSUPP;
trace_usb_ep_fifo_status(ep, ret);
return ret;
}
EXPORT_SYMBOL_GPL(usb_ep_fifo_status);
/**
* usb_ep_fifo_flush - flushes contents of a fifo
* @ep: the endpoint whose fifo is being flushed.
*
* This call may be used to flush the "unclaimed data" that may exist in
* an endpoint fifo after abnormal transaction terminations. The call
* must never be used except when endpoint is not being used for any
* protocol translation.
*
* This routine may be called in interrupt context.
*/
void usb_ep_fifo_flush(struct usb_ep *ep)
{
if (ep->ops->fifo_flush)
ep->ops->fifo_flush(ep);
trace_usb_ep_fifo_flush(ep, 0);
}
EXPORT_SYMBOL_GPL(usb_ep_fifo_flush);
/* ------------------------------------------------------------------------- */
/**
* usb_gadget_frame_number - returns the current frame number
* @gadget: controller that reports the frame number
*
* Returns the usb frame number, normally eleven bits from a SOF packet,
* or negative errno if this device doesn't support this capability.
*/
int usb_gadget_frame_number(struct usb_gadget *gadget)
{
int ret;
ret = gadget->ops->get_frame(gadget);
trace_usb_gadget_frame_number(gadget, ret);
return ret;
}
EXPORT_SYMBOL_GPL(usb_gadget_frame_number);
/**
* usb_gadget_wakeup - tries to wake up the host connected to this gadget
* @gadget: controller used to wake up the host
*
* Returns zero on success, else negative error code if the hardware
* doesn't support such attempts, or its support has not been enabled
* by the usb host. Drivers must return device descriptors that report
* their ability to support this, or hosts won't enable it.
*
* This may also try to use SRP to wake the host and start enumeration,
* even if OTG isn't otherwise in use. OTG devices may also start
* remote wakeup even when hosts don't explicitly enable it.
*/
int usb_gadget_wakeup(struct usb_gadget *gadget)
{
int ret = 0;
if (!gadget->ops->wakeup) {
ret = -EOPNOTSUPP;
goto out;
}
ret = gadget->ops->wakeup(gadget);
out:
trace_usb_gadget_wakeup(gadget, ret);
return ret;
}
EXPORT_SYMBOL_GPL(usb_gadget_wakeup);
/**
* usb_gadget_set_selfpowered - sets the device selfpowered feature.
* @gadget:the device being declared as self-powered
*
* this affects the device status reported by the hardware driver
* to reflect that it now has a local power supply.
*
* returns zero on success, else negative errno.
*/
int usb_gadget_set_selfpowered(struct usb_gadget *gadget)
{
int ret = 0;
if (!gadget->ops->set_selfpowered) {
ret = -EOPNOTSUPP;
goto out;
}
ret = gadget->ops->set_selfpowered(gadget, 1);
out:
trace_usb_gadget_set_selfpowered(gadget, ret);
return ret;
}
EXPORT_SYMBOL_GPL(usb_gadget_set_selfpowered);
/**
* usb_gadget_clear_selfpowered - clear the device selfpowered feature.
* @gadget:the device being declared as bus-powered
*
* this affects the device status reported by the hardware driver.
* some hardware may not support bus-powered operation, in which
* case this feature's value can never change.
*
* returns zero on success, else negative errno.
*/
int usb_gadget_clear_selfpowered(struct usb_gadget *gadget)
{
int ret = 0;
if (!gadget->ops->set_selfpowered) {
ret = -EOPNOTSUPP;
goto out;
}
ret = gadget->ops->set_selfpowered(gadget, 0);
out:
trace_usb_gadget_clear_selfpowered(gadget, ret);
return ret;
}
EXPORT_SYMBOL_GPL(usb_gadget_clear_selfpowered);
/**
* usb_gadget_vbus_connect - Notify controller that VBUS is powered
* @gadget:The device which now has VBUS power.
* Context: can sleep
*
* This call is used by a driver for an external transceiver (or GPIO)
* that detects a VBUS power session starting. Common responses include
* resuming the controller, activating the D+ (or D-) pullup to let the
* host detect that a USB device is attached, and starting to draw power
* (8mA or possibly more, especially after SET_CONFIGURATION).
*
* Returns zero on success, else negative errno.
*/
int usb_gadget_vbus_connect(struct usb_gadget *gadget)
{
int ret = 0;
if (!gadget->ops->vbus_session) {
ret = -EOPNOTSUPP;
goto out;
}
ret = gadget->ops->vbus_session(gadget, 1);
out:
trace_usb_gadget_vbus_connect(gadget, ret);
return ret;
}
EXPORT_SYMBOL_GPL(usb_gadget_vbus_connect);
/**
* usb_gadget_vbus_draw - constrain controller's VBUS power usage
* @gadget:The device whose VBUS usage is being described
* @mA:How much current to draw, in milliAmperes. This should be twice
* the value listed in the configuration descriptor bMaxPower field.
*
* This call is used by gadget drivers during SET_CONFIGURATION calls,
* reporting how much power the device may consume. For example, this
* could affect how quickly batteries are recharged.
*
* Returns zero on success, else negative errno.
*/
int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA)
{
int ret = 0;
if (!gadget->ops->vbus_draw) {
ret = -EOPNOTSUPP;
goto out;
}
ret = gadget->ops->vbus_draw(gadget, mA);
if (!ret)
gadget->mA = mA;
out:
trace_usb_gadget_vbus_draw(gadget, ret);
return ret;
}
EXPORT_SYMBOL_GPL(usb_gadget_vbus_draw);
/**
* usb_gadget_vbus_disconnect - notify controller about VBUS session end
* @gadget:the device whose VBUS supply is being described
* Context: can sleep
*
* This call is used by a driver for an external transceiver (or GPIO)
* that detects a VBUS power session ending. Common responses include
* reversing everything done in usb_gadget_vbus_connect().
*
* Returns zero on success, else negative errno.
*/
int usb_gadget_vbus_disconnect(struct usb_gadget *gadget)
{
int ret = 0;
if (!gadget->ops->vbus_session) {
ret = -EOPNOTSUPP;
goto out;
}
ret = gadget->ops->vbus_session(gadget, 0);
out:
trace_usb_gadget_vbus_disconnect(gadget, ret);
return ret;
}
EXPORT_SYMBOL_GPL(usb_gadget_vbus_disconnect);
/**
* usb_gadget_connect - software-controlled connect to USB host
* @gadget:the peripheral being connected
*
* Enables the D+ (or potentially D-) pullup. The host will start
* enumerating this gadget when the pullup is active and a VBUS session
* is active (the link is powered). This pullup is always enabled unless
* usb_gadget_disconnect() has been used to disable it.
*
* Returns zero on success, else negative errno.
*/
int usb_gadget_connect(struct usb_gadget *gadget)
{
int ret = 0;
if (!gadget->ops->pullup) {
ret = -EOPNOTSUPP;
goto out;
}
if (gadget->deactivated) {
/*
* If gadget is deactivated we only save new state.
* Gadget will be connected automatically after activation.
*/
gadget->connected = true;
goto out;
}
ret = gadget->ops->pullup(gadget, 1);
if (!ret)
gadget->connected = 1;
out:
trace_usb_gadget_connect(gadget, ret);
return ret;
}
EXPORT_SYMBOL_GPL(usb_gadget_connect);
/**
* usb_gadget_disconnect - software-controlled disconnect from USB host
* @gadget:the peripheral being disconnected
*
* Disables the D+ (or potentially D-) pullup, which the host may see
* as a disconnect (when a VBUS session is active). Not all systems
* support software pullup controls.
*
* Following a successful disconnect, invoke the ->disconnect() callback
* for the current gadget driver so that UDC drivers don't need to.
*
* Returns zero on success, else negative errno.
*/
int usb_gadget_disconnect(struct usb_gadget *gadget)
{
int ret = 0;
if (!gadget->ops->pullup) {
ret = -EOPNOTSUPP;
goto out;
}
if (gadget->deactivated) {
/*
* If gadget is deactivated we only save new state.
* Gadget will stay disconnected after activation.
*/
gadget->connected = false;
goto out;
}
ret = gadget->ops->pullup(gadget, 0);
if (!ret) {
gadget->connected = 0;
gadget->udc->driver->disconnect(gadget);
}
out:
trace_usb_gadget_disconnect(gadget, ret);
return ret;
}
EXPORT_SYMBOL_GPL(usb_gadget_disconnect);
/**
* usb_gadget_deactivate - deactivate function which is not ready to work
* @gadget: the peripheral being deactivated
*
* This routine may be used during the gadget driver bind() call to prevent
* the peripheral from ever being visible to the USB host, unless later
* usb_gadget_activate() is called. For example, user mode components may
* need to be activated before the system can talk to hosts.
*
* Returns zero on success, else negative errno.
*/
int usb_gadget_deactivate(struct usb_gadget *gadget)
{
int ret = 0;
if (gadget->deactivated)
goto out;
if (gadget->connected) {
ret = usb_gadget_disconnect(gadget);
if (ret)
goto out;
/*
* If gadget was being connected before deactivation, we want
* to reconnect it in usb_gadget_activate().
*/
gadget->connected = true;
}
gadget->deactivated = true;
out:
trace_usb_gadget_deactivate(gadget, ret);
return ret;
}
EXPORT_SYMBOL_GPL(usb_gadget_deactivate);
/**
* usb_gadget_activate - activate function which is not ready to work
* @gadget: the peripheral being activated
*
* This routine activates gadget which was previously deactivated with
* usb_gadget_deactivate() call. It calls usb_gadget_connect() if needed.
*
* Returns zero on success, else negative errno.
*/
int usb_gadget_activate(struct usb_gadget *gadget)
{
int ret = 0;
if (!gadget->deactivated)
goto out;
gadget->deactivated = false;
/*
* If gadget has been connected before deactivation, or became connected
* while it was being deactivated, we call usb_gadget_connect().
*/
if (gadget->connected)
ret = usb_gadget_connect(gadget);
out:
trace_usb_gadget_activate(gadget, ret);
return ret;
}
EXPORT_SYMBOL_GPL(usb_gadget_activate);
/* ------------------------------------------------------------------------- */
#ifdef CONFIG_HAS_DMA
int usb_gadget_map_request_by_dev(struct device *dev,
struct usb_request *req, int is_in)
{
if (req->length == 0)
return 0;
if (req->num_sgs) {
int mapped;
mapped = dma_map_sg(dev, req->sg, req->num_sgs,
is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
if (mapped == 0) {
dev_err(dev, "failed to map SGs\n");
return -EFAULT;
}
req->num_mapped_sgs = mapped;
} else {
if (is_vmalloc_addr(req->buf)) {
dev_err(dev, "buffer is not dma capable\n");
return -EFAULT;
} else if (object_is_on_stack(req->buf)) {
dev_err(dev, "buffer is on stack\n");
return -EFAULT;
}
req->dma = dma_map_single(dev, req->buf, req->length,
is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
if (dma_mapping_error(dev, req->dma)) {
dev_err(dev, "failed to map buffer\n");
return -EFAULT;
}
req->dma_mapped = 1;
}
return 0;
}
EXPORT_SYMBOL_GPL(usb_gadget_map_request_by_dev);
int usb_gadget_map_request(struct usb_gadget *gadget,
struct usb_request *req, int is_in)
{
return usb_gadget_map_request_by_dev(gadget->dev.parent, req, is_in);
}
EXPORT_SYMBOL_GPL(usb_gadget_map_request);
void usb_gadget_unmap_request_by_dev(struct device *dev,
struct usb_request *req, int is_in)
{
if (req->length == 0)
return;
if (req->num_mapped_sgs) {
dma_unmap_sg(dev, req->sg, req->num_sgs,
is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
req->num_mapped_sgs = 0;
} else if (req->dma_mapped) {
dma_unmap_single(dev, req->dma, req->length,
is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
req->dma_mapped = 0;
}
}
EXPORT_SYMBOL_GPL(usb_gadget_unmap_request_by_dev);
void usb_gadget_unmap_request(struct usb_gadget *gadget,
struct usb_request *req, int is_in)
{
usb_gadget_unmap_request_by_dev(gadget->dev.parent, req, is_in);
}
EXPORT_SYMBOL_GPL(usb_gadget_unmap_request);
#endif /* CONFIG_HAS_DMA */
/* ------------------------------------------------------------------------- */
/**
* usb_gadget_giveback_request - give the request back to the gadget layer
* Context: in_interrupt()
*
* This is called by device controller drivers in order to return the
* completed request back to the gadget layer.
*/
void usb_gadget_giveback_request(struct usb_ep *ep,
struct usb_request *req)
{
if (likely(req->status == 0))
usb_led_activity(USB_LED_EVENT_GADGET);
trace_usb_gadget_giveback_request(ep, req, 0);
req->complete(ep, req);
}
EXPORT_SYMBOL_GPL(usb_gadget_giveback_request);
/* ------------------------------------------------------------------------- */
/**
* gadget_find_ep_by_name - returns ep whose name is the same as sting passed
* in second parameter or NULL if searched endpoint not found
* @g: controller to check for quirk
* @name: name of searched endpoint
*/
struct usb_ep *gadget_find_ep_by_name(struct usb_gadget *g, const char *name)
{
struct usb_ep *ep;
gadget_for_each_ep(ep, g) {
if (!strcmp(ep->name, name))
return ep;
}
return NULL;
}
EXPORT_SYMBOL_GPL(gadget_find_ep_by_name);
/* ------------------------------------------------------------------------- */
int usb_gadget_ep_match_desc(struct usb_gadget *gadget,
struct usb_ep *ep, struct usb_endpoint_descriptor *desc,
struct usb_ss_ep_comp_descriptor *ep_comp)
{
u8 type;
u16 max;
int num_req_streams = 0;
/* endpoint already claimed? */
if (ep->claimed)
return 0;
type = usb_endpoint_type(desc);
max = usb_endpoint_maxp(desc);
if (usb_endpoint_dir_in(desc) && !ep->caps.dir_in)
return 0;
if (usb_endpoint_dir_out(desc) && !ep->caps.dir_out)
return 0;
if (max > ep->maxpacket_limit)
return 0;
/* "high bandwidth" works only at high speed */
if (!gadget_is_dualspeed(gadget) && usb_endpoint_maxp_mult(desc) > 1)
return 0;
switch (type) {
case USB_ENDPOINT_XFER_CONTROL:
/* only support ep0 for portable CONTROL traffic */
return 0;
case USB_ENDPOINT_XFER_ISOC:
if (!ep->caps.type_iso)
return 0;
/* ISO: limit 1023 bytes full speed, 1024 high/super speed */
if (!gadget_is_dualspeed(gadget) && max > 1023)
return 0;
break;
case USB_ENDPOINT_XFER_BULK:
if (!ep->caps.type_bulk)
return 0;
if (ep_comp && gadget_is_superspeed(gadget)) {
/* Get the number of required streams from the
* EP companion descriptor and see if the EP
* matches it
*/
num_req_streams = ep_comp->bmAttributes & 0x1f;
if (num_req_streams > ep->max_streams)
return 0;
}
break;
case USB_ENDPOINT_XFER_INT:
/* Bulk endpoints handle interrupt transfers,
* except the toggle-quirky iso-synch kind
*/
if (!ep->caps.type_int && !ep->caps.type_bulk)
return 0;
/* INT: limit 64 bytes full speed, 1024 high/super speed */
if (!gadget_is_dualspeed(gadget) && max > 64)
return 0;
break;
}
return 1;
}
EXPORT_SYMBOL_GPL(usb_gadget_ep_match_desc);
/* ------------------------------------------------------------------------- */
static void usb_gadget_state_work(struct work_struct *work)
{
struct usb_gadget *gadget = work_to_gadget(work);
struct usb_udc *udc = gadget->udc;
if (udc)
sysfs_notify(&udc->dev.kobj, NULL, "state");
}
void usb_gadget_set_state(struct usb_gadget *gadget,
enum usb_device_state state)
{
gadget->state = state;
schedule_work(&gadget->work);
}
EXPORT_SYMBOL_GPL(usb_gadget_set_state);
/* ------------------------------------------------------------------------- */
static void usb_udc_connect_control(struct usb_udc *udc)
{
if (udc->vbus)
usb_gadget_connect(udc->gadget);
else
usb_gadget_disconnect(udc->gadget);
}
/**
* usb_udc_vbus_handler - updates the udc core vbus status, and try to
* connect or disconnect gadget
* @gadget: The gadget which vbus change occurs
* @status: The vbus status
*
* The udc driver calls it when it wants to connect or disconnect gadget
* according to vbus status.
*/
void usb_udc_vbus_handler(struct usb_gadget *gadget, bool status)
{
struct usb_udc *udc = gadget->udc;
if (udc) {
udc->vbus = status;
usb_udc_connect_control(udc);
}
}
EXPORT_SYMBOL_GPL(usb_udc_vbus_handler);
/**
* usb_gadget_udc_reset - notifies the udc core that bus reset occurs
* @gadget: The gadget which bus reset occurs
* @driver: The gadget driver we want to notify
*
* If the udc driver has bus reset handler, it needs to call this when the bus
* reset occurs, it notifies the gadget driver that the bus reset occurs as
* well as updates gadget state.
*/
void usb_gadget_udc_reset(struct usb_gadget *gadget,
struct usb_gadget_driver *driver)
{
driver->reset(gadget);
usb_gadget_set_state(gadget, USB_STATE_DEFAULT);
}
EXPORT_SYMBOL_GPL(usb_gadget_udc_reset);
/**
* usb_gadget_udc_start - tells usb device controller to start up
* @udc: The UDC to be started
*
* This call is issued by the UDC Class driver when it's about
* to register a gadget driver to the device controller, before
* calling gadget driver's bind() method.
*
* It allows the controller to be powered off until strictly
* necessary to have it powered on.
*
* Returns zero on success, else negative errno.
*/
static inline int usb_gadget_udc_start(struct usb_udc *udc)
{
return udc->gadget->ops->udc_start(udc->gadget, udc->driver);
}
/**
* usb_gadget_udc_stop - tells usb device controller we don't need it anymore
* @gadget: The device we want to stop activity
* @driver: The driver to unbind from @gadget
*
* This call is issued by the UDC Class driver after calling
* gadget driver's unbind() method.
*
* The details are implementation specific, but it can go as
* far as powering off UDC completely and disable its data
* line pullups.
*/
static inline void usb_gadget_udc_stop(struct usb_udc *udc)
{
udc->gadget->ops->udc_stop(udc->gadget);
}
/**
* usb_gadget_udc_set_speed - tells usb device controller speed supported by
* current driver
* @udc: The device we want to set maximum speed
* @speed: The maximum speed to allowed to run
*
* This call is issued by the UDC Class driver before calling
* usb_gadget_udc_start() in order to make sure that we don't try to
* connect on speeds the gadget driver doesn't support.
*/
static inline void usb_gadget_udc_set_speed(struct usb_udc *udc,
enum usb_device_speed speed)
{
if (udc->gadget->ops->udc_set_speed) {
enum usb_device_speed s;
s = min(speed, udc->gadget->max_speed);
udc->gadget->ops->udc_set_speed(udc->gadget, s);
}
}
/**
* usb_udc_release - release the usb_udc struct
* @dev: the dev member within usb_udc
*
* This is called by driver's core in order to free memory once the last
* reference is released.
*/
static void usb_udc_release(struct device *dev)
{
struct usb_udc *udc;
udc = container_of(dev, struct usb_udc, dev);
dev_dbg(dev, "releasing '%s'\n", dev_name(dev));
kfree(udc);
}
static const struct attribute_group *usb_udc_attr_groups[];
static void usb_udc_nop_release(struct device *dev)
{
dev_vdbg(dev, "%s\n", __func__);
}
/* should be called with udc_lock held */
static int check_pending_gadget_drivers(struct usb_udc *udc)
{
struct usb_gadget_driver *driver;
int ret = 0;
list_for_each_entry(driver, &gadget_driver_pending_list, pending)
if (!driver->udc_name || strcmp(driver->udc_name,
dev_name(&udc->dev)) == 0) {
ret = udc_bind_to_driver(udc, driver);
if (ret != -EPROBE_DEFER)
list_del(&driver->pending);
break;
}
return ret;
}
/**
* usb_add_gadget_udc_release - adds a new gadget to the udc class driver list
* @parent: the parent device to this udc. Usually the controller driver's
* device.
* @gadget: the gadget to be added to the list.
* @release: a gadget release function.
*
* Returns zero on success, negative errno otherwise.
* Calls the gadget release function in the latter case.
*/
int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
void (*release)(struct device *dev))
{
struct usb_udc *udc;
int ret = -ENOMEM;
dev_set_name(&gadget->dev, "gadget");
INIT_WORK(&gadget->work, usb_gadget_state_work);
gadget->dev.parent = parent;
if (release)
gadget->dev.release = release;
else
gadget->dev.release = usb_udc_nop_release;
device_initialize(&gadget->dev);
udc = kzalloc(sizeof(*udc), GFP_KERNEL);
if (!udc)
goto err_put_gadget;
device_initialize(&udc->dev);
udc->dev.release = usb_udc_release;
udc->dev.class = udc_class;
udc->dev.groups = usb_udc_attr_groups;
udc->dev.parent = parent;
ret = dev_set_name(&udc->dev, "%s", kobject_name(&parent->kobj));
if (ret)
goto err_put_udc;
ret = device_add(&gadget->dev);
if (ret)
goto err_put_udc;
udc->gadget = gadget;
gadget->udc = udc;
mutex_lock(&udc_lock);
list_add_tail(&udc->list, &udc_list);
ret = device_add(&udc->dev);
if (ret)
goto err_unlist_udc;
usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);
udc->vbus = true;
/* pick up one of pending gadget drivers */
ret = check_pending_gadget_drivers(udc);
if (ret)
goto err_del_udc;
mutex_unlock(&udc_lock);
return 0;
err_del_udc:
device_del(&udc->dev);
err_unlist_udc:
list_del(&udc->list);
mutex_unlock(&udc_lock);
device_del(&gadget->dev);
err_put_udc:
put_device(&udc->dev);
err_put_gadget:
put_device(&gadget->dev);
return ret;
}
EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release);
/**
* usb_get_gadget_udc_name - get the name of the first UDC controller
* This functions returns the name of the first UDC controller in the system.
* Please note that this interface is usefull only for legacy drivers which
* assume that there is only one UDC controller in the system and they need to
* get its name before initialization. There is no guarantee that the UDC
* of the returned name will be still available, when gadget driver registers
* itself.
*
* Returns pointer to string with UDC controller name on success, NULL
* otherwise. Caller should kfree() returned string.
*/
char *usb_get_gadget_udc_name(void)
{
struct usb_udc *udc;
char *name = NULL;
/* For now we take the first available UDC */
mutex_lock(&udc_lock);
list_for_each_entry(udc, &udc_list, list) {
if (!udc->driver) {
name = kstrdup(udc->gadget->name, GFP_KERNEL);
break;
}
}
mutex_unlock(&udc_lock);
return name;
}
EXPORT_SYMBOL_GPL(usb_get_gadget_udc_name);
/**
* usb_add_gadget_udc - adds a new gadget to the udc class driver list
* @parent: the parent device to this udc. Usually the controller
* driver's device.
* @gadget: the gadget to be added to the list
*
* Returns zero on success, negative errno otherwise.
*/
int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget)
{
return usb_add_gadget_udc_release(parent, gadget, NULL);
}
EXPORT_SYMBOL_GPL(usb_add_gadget_udc);
static void usb_gadget_remove_driver(struct usb_udc *udc)
{
dev_dbg(&udc->dev, "unregistering UDC driver [%s]\n",
udc->driver->function);
kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
usb_gadget_disconnect(udc->gadget);
udc->driver->unbind(udc->gadget);
usb_gadget_udc_stop(udc);
udc->driver = NULL;
udc->dev.driver = NULL;
udc->gadget->dev.driver = NULL;
}
/**
* usb_del_gadget_udc - deletes @udc from udc_list
* @gadget: the gadget to be removed.
*
* This, will call usb_gadget_unregister_driver() if
* the @udc is still busy.
*/
void usb_del_gadget_udc(struct usb_gadget *gadget)
{
struct usb_udc *udc = gadget->udc;
if (!udc)
return;
dev_vdbg(gadget->dev.parent, "unregistering gadget\n");
mutex_lock(&udc_lock);
list_del(&udc->list);
if (udc->driver) {
struct usb_gadget_driver *driver = udc->driver;
usb_gadget_remove_driver(udc);
list_add(&driver->pending, &gadget_driver_pending_list);
}
mutex_unlock(&udc_lock);
kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
flush_work(&gadget->work);
device_unregister(&udc->dev);
device_unregister(&gadget->dev);
memset(&gadget->dev, 0x00, sizeof(gadget->dev));
}
EXPORT_SYMBOL_GPL(usb_del_gadget_udc);
/* ------------------------------------------------------------------------- */
static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver)
{
int ret;
dev_dbg(&udc->dev, "registering UDC driver [%s]\n",
driver->function);
udc->driver = driver;
udc->dev.driver = &driver->driver;
udc->gadget->dev.driver = &driver->driver;
usb_gadget_udc_set_speed(udc, driver->max_speed);
ret = driver->bind(udc->gadget, driver);
if (ret)
goto err1;
ret = usb_gadget_udc_start(udc);
if (ret) {
driver->unbind(udc->gadget);
goto err1;
}
usb_udc_connect_control(udc);
kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
return 0;
err1:
if (ret != -EISNAM)
dev_err(&udc->dev, "failed to start %s: %d\n",
udc->driver->function, ret);
udc->driver = NULL;
udc->dev.driver = NULL;
udc->gadget->dev.driver = NULL;
return ret;
}
int usb_gadget_probe_driver(struct usb_gadget_driver *driver)
{
struct usb_udc *udc = NULL;
int ret = -ENODEV;
if (!driver || !driver->bind || !driver->setup)
return -EINVAL;
mutex_lock(&udc_lock);
if (driver->udc_name) {
list_for_each_entry(udc, &udc_list, list) {
ret = strcmp(driver->udc_name, dev_name(&udc->dev));
if (!ret)
break;
}
if (ret)
ret = -ENODEV;
else if (udc->driver)
ret = -EBUSY;
else
goto found;
} else {
list_for_each_entry(udc, &udc_list, list) {
/* For now we take the first one */
if (!udc->driver)
goto found;
}
}
if (!driver->match_existing_only) {
list_add_tail(&driver->pending, &gadget_driver_pending_list);
pr_info("udc-core: couldn't find an available UDC - added [%s] to list of pending drivers\n",
driver->function);
ret = 0;
}
mutex_unlock(&udc_lock);
return ret;
found:
ret = udc_bind_to_driver(udc, driver);
mutex_unlock(&udc_lock);
return ret;
}
EXPORT_SYMBOL_GPL(usb_gadget_probe_driver);
int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
{
struct usb_udc *udc = NULL;
int ret = -ENODEV;
if (!driver || !driver->unbind)
return -EINVAL;
mutex_lock(&udc_lock);
list_for_each_entry(udc, &udc_list, list) {
if (udc->driver == driver) {
usb_gadget_remove_driver(udc);
usb_gadget_set_state(udc->gadget,
USB_STATE_NOTATTACHED);
/* Maybe there is someone waiting for this UDC? */
check_pending_gadget_drivers(udc);
/*
* For now we ignore bind errors as probably it's
* not a valid reason to fail other's gadget unbind
*/
ret = 0;
break;
}
}
if (ret) {
list_del(&driver->pending);
ret = 0;
}
mutex_unlock(&udc_lock);
return ret;
}
EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver);
/* ------------------------------------------------------------------------- */
static ssize_t srp_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t n)
{
struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
if (sysfs_streq(buf, "1"))
usb_gadget_wakeup(udc->gadget);
return n;
}
static DEVICE_ATTR_WO(srp);
static ssize_t soft_connect_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t n)
{
struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
if (!udc->driver) {
dev_err(dev, "soft-connect without a gadget driver\n");
return -EOPNOTSUPP;
}
if (sysfs_streq(buf, "connect")) {
usb_gadget_udc_start(udc);
usb_gadget_connect(udc->gadget);
} else if (sysfs_streq(buf, "disconnect")) {
usb_gadget_disconnect(udc->gadget);
usb_gadget_udc_stop(udc);
} else {
dev_err(dev, "unsupported command '%s'\n", buf);
return -EINVAL;
}
return n;
}
static DEVICE_ATTR_WO(soft_connect);
static ssize_t state_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
struct usb_gadget *gadget = udc->gadget;
return sprintf(buf, "%s\n", usb_state_string(gadget->state));
}
static DEVICE_ATTR_RO(state);
static ssize_t function_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
struct usb_gadget_driver *drv = udc->driver;
if (!drv || !drv->function)
return 0;
return scnprintf(buf, PAGE_SIZE, "%s\n", drv->function);
}
static DEVICE_ATTR_RO(function);
#define USB_UDC_SPEED_ATTR(name, param) \
ssize_t name##_show(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ \
struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
return scnprintf(buf, PAGE_SIZE, "%s\n", \
usb_speed_string(udc->gadget->param)); \
} \
static DEVICE_ATTR_RO(name)
static USB_UDC_SPEED_ATTR(current_speed, speed);
static USB_UDC_SPEED_ATTR(maximum_speed, max_speed);
#define USB_UDC_ATTR(name) \
ssize_t name##_show(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ \
struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
struct usb_gadget *gadget = udc->gadget; \
\
return scnprintf(buf, PAGE_SIZE, "%d\n", gadget->name); \
} \
static DEVICE_ATTR_RO(name)
static USB_UDC_ATTR(is_otg);
static USB_UDC_ATTR(is_a_peripheral);
static USB_UDC_ATTR(b_hnp_enable);
static USB_UDC_ATTR(a_hnp_support);
static USB_UDC_ATTR(a_alt_hnp_support);
static USB_UDC_ATTR(is_selfpowered);
static struct attribute *usb_udc_attrs[] = {
&dev_attr_srp.attr,
&dev_attr_soft_connect.attr,
&dev_attr_state.attr,
&dev_attr_function.attr,
&dev_attr_current_speed.attr,
&dev_attr_maximum_speed.attr,
&dev_attr_is_otg.attr,
&dev_attr_is_a_peripheral.attr,
&dev_attr_b_hnp_enable.attr,
&dev_attr_a_hnp_support.attr,
&dev_attr_a_alt_hnp_support.attr,
&dev_attr_is_selfpowered.attr,
NULL,
};
static const struct attribute_group usb_udc_attr_group = {
.attrs = usb_udc_attrs,
};
static const struct attribute_group *usb_udc_attr_groups[] = {
&usb_udc_attr_group,
NULL,
};
static int usb_udc_uevent(struct device *dev, struct kobj_uevent_env *env)
{
struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
int ret;
ret = add_uevent_var(env, "USB_UDC_NAME=%s", udc->gadget->name);
if (ret) {
dev_err(dev, "failed to add uevent USB_UDC_NAME\n");
return ret;
}
if (udc->driver) {
ret = add_uevent_var(env, "USB_UDC_DRIVER=%s",
udc->driver->function);
if (ret) {
dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n");
return ret;
}
}
return 0;
}
static int __init usb_udc_init(void)
{
udc_class = class_create(THIS_MODULE, "udc");
if (IS_ERR(udc_class)) {
pr_err("failed to create udc class --> %ld\n",
PTR_ERR(udc_class));
return PTR_ERR(udc_class);
}
udc_class->dev_uevent = usb_udc_uevent;
return 0;
}
subsys_initcall(usb_udc_init);
static void __exit usb_udc_exit(void)
{
class_destroy(udc_class);
}
module_exit(usb_udc_exit);
MODULE_DESCRIPTION("UDC Framework");
MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
MODULE_LICENSE("GPL v2");
