| /* |
| * <linux/usb/gadget.h> |
| * |
| * We call the USB code inside a Linux-based peripheral device a "gadget" |
| * driver, except for the hardware-specific bus glue. One USB host can |
| * master many USB gadgets, but the gadgets are only slaved to one host. |
| * |
| * |
| * (C) Copyright 2002-2004 by David Brownell |
| * All Rights Reserved. |
| * |
| * This software is licensed under the GNU GPL version 2. |
| */ |
| |
| #ifndef __LINUX_USB_GADGET_H |
| #define __LINUX_USB_GADGET_H |
| |
| #include <linux/device.h> |
| #include <linux/errno.h> |
| #include <linux/init.h> |
| #include <linux/list.h> |
| #include <linux/slab.h> |
| #include <linux/scatterlist.h> |
| #include <linux/types.h> |
| #include <linux/usb/ch9.h> |
| |
| struct usb_ep; |
| |
| /** |
| * struct usb_request - describes one i/o request |
| * @buf: Buffer used for data. Always provide this; some controllers |
| * only use PIO, or don't use DMA for some endpoints. |
| * @dma: DMA address corresponding to 'buf'. If you don't set this |
| * field, and the usb controller needs one, it is responsible |
| * for mapping and unmapping the buffer. |
| * @sg: a scatterlist for SG-capable controllers. |
| * @num_sgs: number of SG entries |
| * @num_mapped_sgs: number of SG entries mapped to DMA (internal) |
| * @length: Length of that data |
| * @stream_id: The stream id, when USB3.0 bulk streams are being used |
| * @no_interrupt: If true, hints that no completion irq is needed. |
| * Helpful sometimes with deep request queues that are handled |
| * directly by DMA controllers. |
| * @zero: If true, when writing data, makes the last packet be "short" |
| * by adding a zero length packet as needed; |
| * @short_not_ok: When reading data, makes short packets be |
| * treated as errors (queue stops advancing till cleanup). |
| * @complete: Function called when request completes, so this request and |
| * its buffer may be re-used. The function will always be called with |
| * interrupts disabled, and it must not sleep. |
| * Reads terminate with a short packet, or when the buffer fills, |
| * whichever comes first. When writes terminate, some data bytes |
| * will usually still be in flight (often in a hardware fifo). |
| * Errors (for reads or writes) stop the queue from advancing |
| * until the completion function returns, so that any transfers |
| * invalidated by the error may first be dequeued. |
| * @context: For use by the completion callback |
| * @list: For use by the gadget driver. |
| * @status: Reports completion code, zero or a negative errno. |
| * Normally, faults block the transfer queue from advancing until |
| * the completion callback returns. |
| * Code "-ESHUTDOWN" indicates completion caused by device disconnect, |
| * or when the driver disabled the endpoint. |
| * @actual: Reports bytes transferred to/from the buffer. For reads (OUT |
| * transfers) this may be less than the requested length. If the |
| * short_not_ok flag is set, short reads are treated as errors |
| * even when status otherwise indicates successful completion. |
| * Note that for writes (IN transfers) some data bytes may still |
| * reside in a device-side FIFO when the request is reported as |
| * complete. |
| * |
| * These are allocated/freed through the endpoint they're used with. The |
| * hardware's driver can add extra per-request data to the memory it returns, |
| * which often avoids separate memory allocations (potential failures), |
| * later when the request is queued. |
| * |
| * Request flags affect request handling, such as whether a zero length |
| * packet is written (the "zero" flag), whether a short read should be |
| * treated as an error (blocking request queue advance, the "short_not_ok" |
| * flag), or hinting that an interrupt is not required (the "no_interrupt" |
| * flag, for use with deep request queues). |
| * |
| * Bulk endpoints can use any size buffers, and can also be used for interrupt |
| * transfers. interrupt-only endpoints can be much less functional. |
| * |
| * NOTE: this is analogous to 'struct urb' on the host side, except that |
| * it's thinner and promotes more pre-allocation. |
| */ |
| |
| struct usb_request { |
| void *buf; |
| unsigned length; |
| dma_addr_t dma; |
| |
| struct scatterlist *sg; |
| unsigned num_sgs; |
| unsigned num_mapped_sgs; |
| |
| unsigned stream_id:16; |
| unsigned no_interrupt:1; |
| unsigned zero:1; |
| unsigned short_not_ok:1; |
| |
| void (*complete)(struct usb_ep *ep, |
| struct usb_request *req); |
| void *context; |
| struct list_head list; |
| |
| int status; |
| unsigned actual; |
| }; |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* endpoint-specific parts of the api to the usb controller hardware. |
| * unlike the urb model, (de)multiplexing layers are not required. |
| * (so this api could slash overhead if used on the host side...) |
| * |
| * note that device side usb controllers commonly differ in how many |
| * endpoints they support, as well as their capabilities. |
| */ |
| struct usb_ep_ops { |
| int (*enable) (struct usb_ep *ep, |
| const struct usb_endpoint_descriptor *desc); |
| int (*disable) (struct usb_ep *ep); |
| |
| struct usb_request *(*alloc_request) (struct usb_ep *ep, |
| gfp_t gfp_flags); |
| void (*free_request) (struct usb_ep *ep, struct usb_request *req); |
| |
| int (*queue) (struct usb_ep *ep, struct usb_request *req, |
| gfp_t gfp_flags); |
| int (*dequeue) (struct usb_ep *ep, struct usb_request *req); |
| |
| int (*set_halt) (struct usb_ep *ep, int value); |
| int (*set_wedge) (struct usb_ep *ep); |
| |
| int (*fifo_status) (struct usb_ep *ep); |
| void (*fifo_flush) (struct usb_ep *ep); |
| }; |
| |
| /** |
| * struct usb_ep - device side representation of USB endpoint |
| * @name:identifier for the endpoint, such as "ep-a" or "ep9in-bulk" |
| * @ops: Function pointers used to access hardware-specific operations. |
| * @ep_list:the gadget's ep_list holds all of its endpoints |
| * @maxpacket:The maximum packet size used on this endpoint. The initial |
| * value can sometimes be reduced (hardware allowing), according to |
| * the endpoint descriptor used to configure the endpoint. |
| * @max_streams: The maximum number of streams supported |
| * by this EP (0 - 16, actual number is 2^n) |
| * @mult: multiplier, 'mult' value for SS Isoc EPs |
| * @maxburst: the maximum number of bursts supported by this EP (for usb3) |
| * @driver_data:for use by the gadget driver. |
| * @address: used to identify the endpoint when finding descriptor that |
| * matches connection speed |
| * @desc: endpoint descriptor. This pointer is set before the endpoint is |
| * enabled and remains valid until the endpoint is disabled. |
| * @comp_desc: In case of SuperSpeed support, this is the endpoint companion |
| * descriptor that is used to configure the endpoint |
| * |
| * the bus controller driver lists all the general purpose endpoints in |
| * gadget->ep_list. the control endpoint (gadget->ep0) is not in that list, |
| * and is accessed only in response to a driver setup() callback. |
| */ |
| struct usb_ep { |
| void *driver_data; |
| |
| const char *name; |
| const struct usb_ep_ops *ops; |
| struct list_head ep_list; |
| unsigned maxpacket:16; |
| unsigned max_streams:16; |
| unsigned mult:2; |
| unsigned maxburst:5; |
| u8 address; |
| const struct usb_endpoint_descriptor *desc; |
| const struct usb_ss_ep_comp_descriptor *comp_desc; |
| }; |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /** |
| * 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".) |
| * |
| * returns zero, or a negative error code. |
| */ |
| static inline int usb_ep_enable(struct usb_ep *ep) |
| { |
| return ep->ops->enable(ep, ep->desc); |
| } |
| |
| /** |
| * 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. |
| * |
| * returns zero, or a negative error code. |
| */ |
| static inline int usb_ep_disable(struct usb_ep *ep) |
| { |
| return ep->ops->disable(ep); |
| } |
| |
| /** |
| * 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. |
| */ |
| static inline struct usb_request *usb_ep_alloc_request(struct usb_ep *ep, |
| gfp_t gfp_flags) |
| { |
| return ep->ops->alloc_request(ep, gfp_flags); |
| } |
| |
| /** |
| * 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). |
| */ |
| static inline void usb_ep_free_request(struct usb_ep *ep, |
| struct usb_request *req) |
| { |
| ep->ops->free_request(ep, req); |
| } |
| |
| /** |
| * 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. |
| * |
| * 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. |
| */ |
| static inline int usb_ep_queue(struct usb_ep *ep, |
| struct usb_request *req, gfp_t gfp_flags) |
| { |
| return ep->ops->queue(ep, req, gfp_flags); |
| } |
| |
| /** |
| * 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 its |
| * completion routine is called (with status -ECONNRESET); else a negative |
| * error code is returned. |
| * |
| * 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). |
| */ |
| static inline int usb_ep_dequeue(struct usb_ep *ep, struct usb_request *req) |
| { |
| return ep->ops->dequeue(ep, req); |
| } |
| |
| /** |
| * 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. |
| * |
| * 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. |
| */ |
| static inline int usb_ep_set_halt(struct usb_ep *ep) |
| { |
| return ep->ops->set_halt(ep, 1); |
| } |
| |
| /** |
| * 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. |
| * |
| * 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. |
| */ |
| static inline int usb_ep_clear_halt(struct usb_ep *ep) |
| { |
| return ep->ops->set_halt(ep, 0); |
| } |
| |
| /** |
| * 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. |
| * |
| * Returns zero on success, else negative errno. |
| */ |
| static inline int |
| usb_ep_set_wedge(struct usb_ep *ep) |
| { |
| if (ep->ops->set_wedge) |
| return ep->ops->set_wedge(ep); |
| else |
| return ep->ops->set_halt(ep, 1); |
| } |
| |
| /** |
| * 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 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. |
| */ |
| static inline int usb_ep_fifo_status(struct usb_ep *ep) |
| { |
| if (ep->ops->fifo_status) |
| return ep->ops->fifo_status(ep); |
| else |
| return -EOPNOTSUPP; |
| } |
| |
| /** |
| * 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. |
| */ |
| static inline void usb_ep_fifo_flush(struct usb_ep *ep) |
| { |
| if (ep->ops->fifo_flush) |
| ep->ops->fifo_flush(ep); |
| } |
| |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| struct usb_dcd_config_params { |
| __u8 bU1devExitLat; /* U1 Device exit Latency */ |
| #define USB_DEFAULT_U1_DEV_EXIT_LAT 0x01 /* Less then 1 microsec */ |
| __le16 bU2DevExitLat; /* U2 Device exit Latency */ |
| #define USB_DEFAULT_U2_DEV_EXIT_LAT 0x1F4 /* Less then 500 microsec */ |
| }; |
| |
| |
| struct usb_gadget; |
| struct usb_gadget_driver; |
| |
| /* the rest of the api to the controller hardware: device operations, |
| * which don't involve endpoints (or i/o). |
| */ |
| struct usb_gadget_ops { |
| int (*get_frame)(struct usb_gadget *); |
| int (*wakeup)(struct usb_gadget *); |
| int (*set_selfpowered) (struct usb_gadget *, int is_selfpowered); |
| int (*vbus_session) (struct usb_gadget *, int is_active); |
| int (*vbus_draw) (struct usb_gadget *, unsigned mA); |
| int (*pullup) (struct usb_gadget *, int is_on); |
| int (*ioctl)(struct usb_gadget *, |
| unsigned code, unsigned long param); |
| void (*get_config_params)(struct usb_dcd_config_params *); |
| int (*udc_start)(struct usb_gadget *, |
| struct usb_gadget_driver *); |
| int (*udc_stop)(struct usb_gadget *, |
| struct usb_gadget_driver *); |
| }; |
| |
| /** |
| * struct usb_gadget - represents a usb slave device |
| * @ops: Function pointers used to access hardware-specific operations. |
| * @ep0: Endpoint zero, used when reading or writing responses to |
| * driver setup() requests |
| * @ep_list: List of other endpoints supported by the device. |
| * @speed: Speed of current connection to USB host. |
| * @max_speed: Maximal speed the UDC can handle. UDC must support this |
| * and all slower speeds. |
| * @sg_supported: true if we can handle scatter-gather |
| * @is_otg: True if the USB device port uses a Mini-AB jack, so that the |
| * gadget driver must provide a USB OTG descriptor. |
| * @is_a_peripheral: False unless is_otg, the "A" end of a USB cable |
| * is in the Mini-AB jack, and HNP has been used to switch roles |
| * so that the "A" device currently acts as A-Peripheral, not A-Host. |
| * @a_hnp_support: OTG device feature flag, indicating that the A-Host |
| * supports HNP at this port. |
| * @a_alt_hnp_support: OTG device feature flag, indicating that the A-Host |
| * only supports HNP on a different root port. |
| * @b_hnp_enable: OTG device feature flag, indicating that the A-Host |
| * enabled HNP support. |
| * @name: Identifies the controller hardware type. Used in diagnostics |
| * and sometimes configuration. |
| * @dev: Driver model state for this abstract device. |
| * @out_epnum: last used out ep number |
| * @in_epnum: last used in ep number |
| * |
| * Gadgets have a mostly-portable "gadget driver" implementing device |
| * functions, handling all usb configurations and interfaces. Gadget |
| * drivers talk to hardware-specific code indirectly, through ops vectors. |
| * That insulates the gadget driver from hardware details, and packages |
| * the hardware endpoints through generic i/o queues. The "usb_gadget" |
| * and "usb_ep" interfaces provide that insulation from the hardware. |
| * |
| * Except for the driver data, all fields in this structure are |
| * read-only to the gadget driver. That driver data is part of the |
| * "driver model" infrastructure in 2.6 (and later) kernels, and for |
| * earlier systems is grouped in a similar structure that's not known |
| * to the rest of the kernel. |
| * |
| * Values of the three OTG device feature flags are updated before the |
| * setup() call corresponding to USB_REQ_SET_CONFIGURATION, and before |
| * driver suspend() calls. They are valid only when is_otg, and when the |
| * device is acting as a B-Peripheral (so is_a_peripheral is false). |
| */ |
| struct usb_gadget { |
| /* readonly to gadget driver */ |
| const struct usb_gadget_ops *ops; |
| struct usb_ep *ep0; |
| struct list_head ep_list; /* of usb_ep */ |
| enum usb_device_speed speed; |
| enum usb_device_speed max_speed; |
| unsigned sg_supported:1; |
| unsigned is_otg:1; |
| unsigned is_a_peripheral:1; |
| unsigned b_hnp_enable:1; |
| unsigned a_hnp_support:1; |
| unsigned a_alt_hnp_support:1; |
| const char *name; |
| struct device dev; |
| unsigned out_epnum; |
| unsigned in_epnum; |
| }; |
| |
| static inline void set_gadget_data(struct usb_gadget *gadget, void *data) |
| { dev_set_drvdata(&gadget->dev, data); } |
| static inline void *get_gadget_data(struct usb_gadget *gadget) |
| { return dev_get_drvdata(&gadget->dev); } |
| static inline struct usb_gadget *dev_to_usb_gadget(struct device *dev) |
| { |
| return container_of(dev, struct usb_gadget, dev); |
| } |
| |
| /* iterates the non-control endpoints; 'tmp' is a struct usb_ep pointer */ |
| #define gadget_for_each_ep(tmp, gadget) \ |
| list_for_each_entry(tmp, &(gadget)->ep_list, ep_list) |
| |
| |
| /** |
| * gadget_is_dualspeed - return true iff the hardware handles high speed |
| * @g: controller that might support both high and full speeds |
| */ |
| static inline int gadget_is_dualspeed(struct usb_gadget *g) |
| { |
| return g->max_speed >= USB_SPEED_HIGH; |
| } |
| |
| /** |
| * gadget_is_superspeed() - return true if the hardware handles |
| * supperspeed |
| * @g: controller that might support supper speed |
| */ |
| static inline int gadget_is_superspeed(struct usb_gadget *g) |
| { |
| return g->max_speed >= USB_SPEED_SUPER; |
| } |
| |
| /** |
| * gadget_is_otg - return true iff the hardware is OTG-ready |
| * @g: controller that might have a Mini-AB connector |
| * |
| * This is a runtime test, since kernels with a USB-OTG stack sometimes |
| * run on boards which only have a Mini-B (or Mini-A) connector. |
| */ |
| static inline int gadget_is_otg(struct usb_gadget *g) |
| { |
| #ifdef CONFIG_USB_OTG |
| return g->is_otg; |
| #else |
| return 0; |
| #endif |
| } |
| |
| /** |
| * 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. |
| */ |
| static inline int usb_gadget_frame_number(struct usb_gadget *gadget) |
| { |
| return gadget->ops->get_frame(gadget); |
| } |
| |
| /** |
| * 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. |
| */ |
| static inline int usb_gadget_wakeup(struct usb_gadget *gadget) |
| { |
| if (!gadget->ops->wakeup) |
| return -EOPNOTSUPP; |
| return gadget->ops->wakeup(gadget); |
| } |
| |
| /** |
| * 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. |
| */ |
| static inline int usb_gadget_set_selfpowered(struct usb_gadget *gadget) |
| { |
| if (!gadget->ops->set_selfpowered) |
| return -EOPNOTSUPP; |
| return gadget->ops->set_selfpowered(gadget, 1); |
| } |
| |
| /** |
| * 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. |
| */ |
| static inline int usb_gadget_clear_selfpowered(struct usb_gadget *gadget) |
| { |
| if (!gadget->ops->set_selfpowered) |
| return -EOPNOTSUPP; |
| return gadget->ops->set_selfpowered(gadget, 0); |
| } |
| |
| /** |
| * 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. |
| */ |
| static inline int usb_gadget_vbus_connect(struct usb_gadget *gadget) |
| { |
| if (!gadget->ops->vbus_session) |
| return -EOPNOTSUPP; |
| return gadget->ops->vbus_session(gadget, 1); |
| } |
| |
| /** |
| * 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. |
| */ |
| static inline int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA) |
| { |
| if (!gadget->ops->vbus_draw) |
| return -EOPNOTSUPP; |
| return gadget->ops->vbus_draw(gadget, mA); |
| } |
| |
| /** |
| * 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. |
| */ |
| static inline int usb_gadget_vbus_disconnect(struct usb_gadget *gadget) |
| { |
| if (!gadget->ops->vbus_session) |
| return -EOPNOTSUPP; |
| return gadget->ops->vbus_session(gadget, 0); |
| } |
| |
| /** |
| * 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. |
| */ |
| static inline int usb_gadget_connect(struct usb_gadget *gadget) |
| { |
| if (!gadget->ops->pullup) |
| return -EOPNOTSUPP; |
| return gadget->ops->pullup(gadget, 1); |
| } |
| |
| /** |
| * 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. |
| * |
| * 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_connect() 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. |
| */ |
| static inline int usb_gadget_disconnect(struct usb_gadget *gadget) |
| { |
| if (!gadget->ops->pullup) |
| return -EOPNOTSUPP; |
| return gadget->ops->pullup(gadget, 0); |
| } |
| |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /** |
| * struct usb_gadget_driver - driver for usb 'slave' devices |
| * @function: String describing the gadget's function |
| * @max_speed: Highest speed the driver handles. |
| * @setup: Invoked for ep0 control requests that aren't handled by |
| * the hardware level driver. Most calls must be handled by |
| * the gadget driver, including descriptor and configuration |
| * management. The 16 bit members of the setup data are in |
| * USB byte order. Called in_interrupt; this may not sleep. Driver |
| * queues a response to ep0, or returns negative to stall. |
| * @disconnect: Invoked after all transfers have been stopped, |
| * when the host is disconnected. May be called in_interrupt; this |
| * may not sleep. Some devices can't detect disconnect, so this might |
| * not be called except as part of controller shutdown. |
| * @bind: the driver's bind callback |
| * @unbind: Invoked when the driver is unbound from a gadget, |
| * usually from rmmod (after a disconnect is reported). |
| * Called in a context that permits sleeping. |
| * @suspend: Invoked on USB suspend. May be called in_interrupt. |
| * @resume: Invoked on USB resume. May be called in_interrupt. |
| * @driver: Driver model state for this driver. |
| * |
| * Devices are disabled till a gadget driver successfully bind()s, which |
| * means the driver will handle setup() requests needed to enumerate (and |
| * meet "chapter 9" requirements) then do some useful work. |
| * |
| * If gadget->is_otg is true, the gadget driver must provide an OTG |
| * descriptor during enumeration, or else fail the bind() call. In such |
| * cases, no USB traffic may flow until both bind() returns without |
| * having called usb_gadget_disconnect(), and the USB host stack has |
| * initialized. |
| * |
| * Drivers use hardware-specific knowledge to configure the usb hardware. |
| * endpoint addressing is only one of several hardware characteristics that |
| * are in descriptors the ep0 implementation returns from setup() calls. |
| * |
| * Except for ep0 implementation, most driver code shouldn't need change to |
| * run on top of different usb controllers. It'll use endpoints set up by |
| * that ep0 implementation. |
| * |
| * The usb controller driver handles a few standard usb requests. Those |
| * include set_address, and feature flags for devices, interfaces, and |
| * endpoints (the get_status, set_feature, and clear_feature requests). |
| * |
| * Accordingly, the driver's setup() callback must always implement all |
| * get_descriptor requests, returning at least a device descriptor and |
| * a configuration descriptor. Drivers must make sure the endpoint |
| * descriptors match any hardware constraints. Some hardware also constrains |
| * other descriptors. (The pxa250 allows only configurations 1, 2, or 3). |
| * |
| * The driver's setup() callback must also implement set_configuration, |
| * and should also implement set_interface, get_configuration, and |
| * get_interface. Setting a configuration (or interface) is where |
| * endpoints should be activated or (config 0) shut down. |
| * |
| * (Note that only the default control endpoint is supported. Neither |
| * hosts nor devices generally support control traffic except to ep0.) |
| * |
| * Most devices will ignore USB suspend/resume operations, and so will |
| * not provide those callbacks. However, some may need to change modes |
| * when the host is not longer directing those activities. For example, |
| * local controls (buttons, dials, etc) may need to be re-enabled since |
| * the (remote) host can't do that any longer; or an error state might |
| * be cleared, to make the device behave identically whether or not |
| * power is maintained. |
| */ |
| struct usb_gadget_driver { |
| char *function; |
| enum usb_device_speed max_speed; |
| int (*bind)(struct usb_gadget *gadget, |
| struct usb_gadget_driver *driver); |
| void (*unbind)(struct usb_gadget *); |
| int (*setup)(struct usb_gadget *, |
| const struct usb_ctrlrequest *); |
| void (*disconnect)(struct usb_gadget *); |
| void (*suspend)(struct usb_gadget *); |
| void (*resume)(struct usb_gadget *); |
| |
| /* FIXME support safe rmmod */ |
| struct device_driver driver; |
| }; |
| |
| |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* driver modules register and unregister, as usual. |
| * these calls must be made in a context that can sleep. |
| * |
| * these will usually be implemented directly by the hardware-dependent |
| * usb bus interface driver, which will only support a single driver. |
| */ |
| |
| /** |
| * usb_gadget_probe_driver - probe a gadget driver |
| * @driver: the driver being registered |
| * Context: can sleep |
| * |
| * Call this in your gadget driver's module initialization function, |
| * to tell the underlying usb controller driver about your driver. |
| * The @bind() function will be called to bind it to a gadget before this |
| * registration call returns. It's expected that the @bind() function will |
| * be in init sections. |
| */ |
| int usb_gadget_probe_driver(struct usb_gadget_driver *driver); |
| |
| /** |
| * usb_gadget_unregister_driver - unregister a gadget driver |
| * @driver:the driver being unregistered |
| * Context: can sleep |
| * |
| * Call this in your gadget driver's module cleanup function, |
| * to tell the underlying usb controller that your driver is |
| * going away. If the controller is connected to a USB host, |
| * it will first disconnect(). The driver is also requested |
| * to unbind() and clean up any device state, before this procedure |
| * finally returns. It's expected that the unbind() functions |
| * will in in exit sections, so may not be linked in some kernels. |
| */ |
| int usb_gadget_unregister_driver(struct usb_gadget_driver *driver); |
| |
| extern int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget); |
| extern void usb_del_gadget_udc(struct usb_gadget *gadget); |
| extern int udc_attach_driver(const char *name, |
| struct usb_gadget_driver *driver); |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* utility to simplify dealing with string descriptors */ |
| |
| /** |
| * struct usb_string - wraps a C string and its USB id |
| * @id:the (nonzero) ID for this string |
| * @s:the string, in UTF-8 encoding |
| * |
| * If you're using usb_gadget_get_string(), use this to wrap a string |
| * together with its ID. |
| */ |
| struct usb_string { |
| u8 id; |
| const char *s; |
| }; |
| |
| /** |
| * struct usb_gadget_strings - a set of USB strings in a given language |
| * @language:identifies the strings' language (0x0409 for en-us) |
| * @strings:array of strings with their ids |
| * |
| * If you're using usb_gadget_get_string(), use this to wrap all the |
| * strings for a given language. |
| */ |
| struct usb_gadget_strings { |
| u16 language; /* 0x0409 for en-us */ |
| struct usb_string *strings; |
| }; |
| |
| struct usb_gadget_string_container { |
| struct list_head list; |
| u8 *stash[0]; |
| }; |
| |
| /* put descriptor for string with that id into buf (buflen >= 256) */ |
| int usb_gadget_get_string(struct usb_gadget_strings *table, int id, u8 *buf); |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* utility to simplify managing config descriptors */ |
| |
| /* write vector of descriptors into buffer */ |
| int usb_descriptor_fillbuf(void *, unsigned, |
| const struct usb_descriptor_header **); |
| |
| /* build config descriptor from single descriptor vector */ |
| int usb_gadget_config_buf(const struct usb_config_descriptor *config, |
| void *buf, unsigned buflen, const struct usb_descriptor_header **desc); |
| |
| /* copy a NULL-terminated vector of descriptors */ |
| struct usb_descriptor_header **usb_copy_descriptors( |
| struct usb_descriptor_header **); |
| |
| /** |
| * usb_free_descriptors - free descriptors returned by usb_copy_descriptors() |
| * @v: vector of descriptors |
| */ |
| static inline void usb_free_descriptors(struct usb_descriptor_header **v) |
| { |
| kfree(v); |
| } |
| |
| struct usb_function; |
| int usb_assign_descriptors(struct usb_function *f, |
| struct usb_descriptor_header **fs, |
| struct usb_descriptor_header **hs, |
| struct usb_descriptor_header **ss); |
| void usb_free_all_descriptors(struct usb_function *f); |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* utility to simplify map/unmap of usb_requests to/from DMA */ |
| |
| extern int usb_gadget_map_request(struct usb_gadget *gadget, |
| struct usb_request *req, int is_in); |
| |
| extern void usb_gadget_unmap_request(struct usb_gadget *gadget, |
| struct usb_request *req, int is_in); |
| |
| /*-------------------------------------------------------------------------*/ |
| |
| /* utility wrapping a simple endpoint selection policy */ |
| |
| extern struct usb_ep *usb_ep_autoconfig(struct usb_gadget *, |
| struct usb_endpoint_descriptor *); |
| |
| |
| extern struct usb_ep *usb_ep_autoconfig_ss(struct usb_gadget *, |
| struct usb_endpoint_descriptor *, |
| struct usb_ss_ep_comp_descriptor *); |
| |
| extern void usb_ep_autoconfig_reset(struct usb_gadget *); |
| |
| #endif /* __LINUX_USB_GADGET_H */ |