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Diffstat (limited to 'drivers/usb/wusbcore/wa-hc.h')
| -rw-r--r-- | drivers/usb/wusbcore/wa-hc.h | 417 |
1 files changed, 417 insertions, 0 deletions
diff --git a/drivers/usb/wusbcore/wa-hc.h b/drivers/usb/wusbcore/wa-hc.h new file mode 100644 index 00000000000..586d350cdb4 --- /dev/null +++ b/drivers/usb/wusbcore/wa-hc.h @@ -0,0 +1,417 @@ +/* + * HWA Host Controller Driver + * Wire Adapter Control/Data Streaming Iface (WUSB1.0[8]) + * + * Copyright (C) 2005-2006 Intel Corporation + * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version + * 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + * + * + * This driver implements a USB Host Controller (struct usb_hcd) for a + * Wireless USB Host Controller based on the Wireless USB 1.0 + * Host-Wire-Adapter specification (in layman terms, a USB-dongle that + * implements a Wireless USB host). + * + * Check out the Design-overview.txt file in the source documentation + * for other details on the implementation. + * + * Main blocks: + * + * driver glue with the driver API, workqueue daemon + * + * lc RC instance life cycle management (create, destroy...) + * + * hcd glue with the USB API Host Controller Interface API. + * + * nep Notification EndPoint managent: collect notifications + * and queue them with the workqueue daemon. + * + * Handle notifications as coming from the NEP. Sends them + * off others to their respective modules (eg: connect, + * disconnect and reset go to devconnect). + * + * rpipe Remote Pipe management; rpipe is what we use to write + * to an endpoint on a WUSB device that is connected to a + * HWA RC. + * + * xfer Transfer managment -- this is all the code that gets a + * buffer and pushes it to a device (or viceversa). * + * + * Some day a lot of this code will be shared between this driver and + * the drivers for DWA (xfer, rpipe). + * + * All starts at driver.c:hwahc_probe(), when one of this guys is + * connected. hwahc_disconnect() stops it. + * + * During operation, the main driver is devices connecting or + * disconnecting. They cause the HWA RC to send notifications into + * nep.c:hwahc_nep_cb() that will dispatch them to + * notif.c:wa_notif_dispatch(). From there they will fan to cause + * device connects, disconnects, etc. + * + * Note much of the activity is difficult to follow. For example a + * device connect goes to devconnect, which will cause the "fake" root + * hub port to show a connect and stop there. Then khubd will notice + * and call into the rh.c:hwahc_rc_port_reset() code to authenticate + * the device (and this might require user intervention) and enable + * the port. + * + * We also have a timer workqueue going from devconnect.c that + * schedules in hwahc_devconnect_create(). + * + * The rest of the traffic is in the usual entry points of a USB HCD, + * which are hooked up in driver.c:hwahc_rc_driver, and defined in + * hcd.c. + */ + +#ifndef __HWAHC_INTERNAL_H__ +#define __HWAHC_INTERNAL_H__ + +#include <linux/completion.h> +#include <linux/usb.h> +#include <linux/mutex.h> +#include <linux/spinlock.h> +#include <linux/uwb.h> +#include <linux/usb/wusb.h> +#include <linux/usb/wusb-wa.h> + +struct wusbhc; +struct wahc; +extern void wa_urb_enqueue_run(struct work_struct *ws); + +/** + * RPipe instance + * + * @descr's fields are kept in LE, as we need to send it back and + * forth. + * + * @wa is referenced when set + * + * @segs_available is the number of requests segments that still can + * be submitted to the controller without overloading + * it. It is initialized to descr->wRequests when + * aiming. + * + * A rpipe supports a max of descr->wRequests at the same time; before + * submitting seg_lock has to be taken. If segs_avail > 0, then we can + * submit; if not, we have to queue them. + */ +struct wa_rpipe { + struct kref refcnt; + struct usb_rpipe_descriptor descr; + struct usb_host_endpoint *ep; + struct wahc *wa; + spinlock_t seg_lock; + struct list_head seg_list; + atomic_t segs_available; + u8 buffer[1]; /* For reads/writes on USB */ +}; + + +/** + * Instance of a HWA Host Controller + * + * Except where a more specific lock/mutex applies or atomic, all + * fields protected by @mutex. + * + * @wa_descr Can be accessed without locking because it is in + * the same area where the device descriptors were + * read, so it is guaranteed to exist umodified while + * the device exists. + * + * Endianess has been converted to CPU's. + * + * @nep_* can be accessed without locking as its processing is + * serialized; we submit a NEP URB and it comes to + * hwahc_nep_cb(), which won't issue another URB until it is + * done processing it. + * + * @xfer_list: + * + * List of active transfers to verify existence from a xfer id + * gotten from the xfer result message. Can't use urb->list because + * it goes by endpoint, and we don't know the endpoint at the time + * when we get the xfer result message. We can't really rely on the + * pointer (will have to change for 64 bits) as the xfer id is 32 bits. + * + * @xfer_delayed_list: List of transfers that need to be started + * (with a workqueue, because they were + * submitted from an atomic context). + * + * FIXME: this needs to be layered up: a wusbhc layer (for sharing + * comonalities with WHCI), a wa layer (for sharing + * comonalities with DWA-RC). + */ +struct wahc { + struct usb_device *usb_dev; + struct usb_interface *usb_iface; + + /* HC to deliver notifications */ + union { + struct wusbhc *wusb; + struct dwahc *dwa; + }; + + const struct usb_endpoint_descriptor *dto_epd, *dti_epd; + const struct usb_wa_descriptor *wa_descr; + + struct urb *nep_urb; /* Notification EndPoint [lockless] */ + struct edc nep_edc; + void *nep_buffer; + size_t nep_buffer_size; + + atomic_t notifs_queued; + + u16 rpipes; + unsigned long *rpipe_bm; /* rpipe usage bitmap */ + spinlock_t rpipe_bm_lock; /* protect rpipe_bm */ + struct mutex rpipe_mutex; /* assigning resources to endpoints */ + + struct urb *dti_urb; /* URB for reading xfer results */ + struct urb *buf_in_urb; /* URB for reading data in */ + struct edc dti_edc; /* DTI error density counter */ + struct wa_xfer_result *xfer_result; /* real size = dti_ep maxpktsize */ + size_t xfer_result_size; + + s32 status; /* For reading status */ + + struct list_head xfer_list; + struct list_head xfer_delayed_list; + spinlock_t xfer_list_lock; + struct work_struct xfer_work; + atomic_t xfer_id_count; +}; + + +extern int wa_create(struct wahc *wa, struct usb_interface *iface); +extern void __wa_destroy(struct wahc *wa); +void wa_reset_all(struct wahc *wa); + + +/* Miscellaneous constants */ +enum { + /** Max number of EPROTO errors we tolerate on the NEP in a + * period of time */ + HWAHC_EPROTO_MAX = 16, + /** Period of time for EPROTO errors (in jiffies) */ + HWAHC_EPROTO_PERIOD = 4 * HZ, +}; + + +/* Notification endpoint handling */ +extern int wa_nep_create(struct wahc *, struct usb_interface *); +extern void wa_nep_destroy(struct wahc *); + +static inline int wa_nep_arm(struct wahc *wa, gfp_t gfp_mask) +{ + struct urb *urb = wa->nep_urb; + urb->transfer_buffer = wa->nep_buffer; + urb->transfer_buffer_length = wa->nep_buffer_size; + return usb_submit_urb(urb, gfp_mask); +} + +static inline void wa_nep_disarm(struct wahc *wa) +{ + usb_kill_urb(wa->nep_urb); +} + + +/* RPipes */ +static inline void wa_rpipe_init(struct wahc *wa) +{ + spin_lock_init(&wa->rpipe_bm_lock); + mutex_init(&wa->rpipe_mutex); +} + +static inline void wa_init(struct wahc *wa) +{ + edc_init(&wa->nep_edc); + atomic_set(&wa->notifs_queued, 0); + wa_rpipe_init(wa); + edc_init(&wa->dti_edc); + INIT_LIST_HEAD(&wa->xfer_list); + INIT_LIST_HEAD(&wa->xfer_delayed_list); + spin_lock_init(&wa->xfer_list_lock); + INIT_WORK(&wa->xfer_work, wa_urb_enqueue_run); + atomic_set(&wa->xfer_id_count, 1); +} + +/** + * Destroy a pipe (when refcount drops to zero) + * + * Assumes it has been moved to the "QUIESCING" state. + */ +struct wa_xfer; +extern void rpipe_destroy(struct kref *_rpipe); +static inline +void __rpipe_get(struct wa_rpipe *rpipe) +{ + kref_get(&rpipe->refcnt); +} +extern int rpipe_get_by_ep(struct wahc *, struct usb_host_endpoint *, + struct urb *, gfp_t); +static inline void rpipe_put(struct wa_rpipe *rpipe) +{ + kref_put(&rpipe->refcnt, rpipe_destroy); + +} +extern void rpipe_ep_disable(struct wahc *, struct usb_host_endpoint *); +extern int wa_rpipes_create(struct wahc *); +extern void wa_rpipes_destroy(struct wahc *); +static inline void rpipe_avail_dec(struct wa_rpipe *rpipe) +{ + atomic_dec(&rpipe->segs_available); +} + +/** + * Returns true if the rpipe is ready to submit more segments. + */ +static inline int rpipe_avail_inc(struct wa_rpipe *rpipe) +{ + return atomic_inc_return(&rpipe->segs_available) > 0 + && !list_empty(&rpipe->seg_list); +} + + +/* Transferring data */ +extern int wa_urb_enqueue(struct wahc *, struct usb_host_endpoint *, + struct urb *, gfp_t); +extern int wa_urb_dequeue(struct wahc *, struct urb *); +extern void wa_handle_notif_xfer(struct wahc *, struct wa_notif_hdr *); + + +/* Misc + * + * FIXME: Refcounting for the actual @hwahc object is not correct; I + * mean, this should be refcounting on the HCD underneath, but + * it is not. In any case, the semantics for HCD refcounting + * are *weird*...on refcount reaching zero it just frees + * it...no RC specific function is called...unless I miss + * something. + * + * FIXME: has to go away in favour of an 'struct' hcd based sollution + */ +static inline struct wahc *wa_get(struct wahc *wa) +{ + usb_get_intf(wa->usb_iface); + return wa; +} + +static inline void wa_put(struct wahc *wa) +{ + usb_put_intf(wa->usb_iface); +} + + +static inline int __wa_feature(struct wahc *wa, unsigned op, u16 feature) +{ + return usb_control_msg(wa->usb_dev, usb_sndctrlpipe(wa->usb_dev, 0), + op ? USB_REQ_SET_FEATURE : USB_REQ_CLEAR_FEATURE, + USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE, + feature, + wa->usb_iface->cur_altsetting->desc.bInterfaceNumber, + NULL, 0, 1000 /* FIXME: arbitrary */); +} + + +static inline int __wa_set_feature(struct wahc *wa, u16 feature) +{ + return __wa_feature(wa, 1, feature); +} + + +static inline int __wa_clear_feature(struct wahc *wa, u16 feature) +{ + return __wa_feature(wa, 0, feature); +} + + +/** + * Return the status of a Wire Adapter + * + * @wa: Wire Adapter instance + * @returns < 0 errno code on error, or status bitmap as described + * in WUSB1.0[8.3.1.6]. + * + * NOTE: need malloc, some arches don't take USB from the stack + */ +static inline +s32 __wa_get_status(struct wahc *wa) +{ + s32 result; + result = usb_control_msg( + wa->usb_dev, usb_rcvctrlpipe(wa->usb_dev, 0), + USB_REQ_GET_STATUS, + USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE, + 0, wa->usb_iface->cur_altsetting->desc.bInterfaceNumber, + &wa->status, sizeof(wa->status), + 1000 /* FIXME: arbitrary */); + if (result >= 0) + result = wa->status; + return result; +} + + +/** + * Waits until the Wire Adapter's status matches @mask/@value + * + * @wa: Wire Adapter instance. + * @returns < 0 errno code on error, otherwise status. + * + * Loop until the WAs status matches the mask and value (status & mask + * == value). Timeout if it doesn't happen. + * + * FIXME: is there an official specification on how long status + * changes can take? + */ +static inline s32 __wa_wait_status(struct wahc *wa, u32 mask, u32 value) +{ + s32 result; + unsigned loops = 10; + do { + msleep(50); + result = __wa_get_status(wa); + if ((result & mask) == value) + break; + if (loops-- == 0) { + result = -ETIMEDOUT; + break; + } + } while (result >= 0); + return result; +} + + +/** Command @hwahc to stop, @returns 0 if ok, < 0 errno code on error */ +static inline int __wa_stop(struct wahc *wa) +{ + int result; + struct device *dev = &wa->usb_iface->dev; + + result = __wa_clear_feature(wa, WA_ENABLE); + if (result < 0 && result != -ENODEV) { + dev_err(dev, "error commanding HC to stop: %d\n", result); + goto out; + } + result = __wa_wait_status(wa, WA_ENABLE, 0); + if (result < 0 && result != -ENODEV) + dev_err(dev, "error waiting for HC to stop: %d\n", result); +out: + return 0; +} + + +#endif /* #ifndef __HWAHC_INTERNAL_H__ */ |