Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / usb / wusbcore / wa-rpipe.c
diff --git a/kernel/drivers/usb/wusbcore/wa-rpipe.c b/kernel/drivers/usb/wusbcore/wa-rpipe.c
new file mode 100644 (file)
index 0000000..c7ecdbe
--- /dev/null
@@ -0,0 +1,554 @@
+/*
+ * WUSB Wire Adapter
+ * rpipe management
+ *
+ * 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.
+ *
+ *
+ * FIXME: docs
+ *
+ * RPIPE
+ *
+ *   Targeted at different downstream endpoints
+ *
+ *   Descriptor: use to config the remote pipe.
+ *
+ *   The number of blocks could be dynamic (wBlocks in descriptor is
+ *   0)--need to schedule them then.
+ *
+ * Each bit in wa->rpipe_bm represents if an rpipe is being used or
+ * not. Rpipes are represented with a 'struct wa_rpipe' that is
+ * attached to the hcpriv member of a 'struct usb_host_endpoint'.
+ *
+ * When you need to xfer data to an endpoint, you get an rpipe for it
+ * with wa_ep_rpipe_get(), which gives you a reference to the rpipe
+ * and keeps a single one (the first one) with the endpoint. When you
+ * are done transferring, you drop that reference. At the end the
+ * rpipe is always allocated and bound to the endpoint. There it might
+ * be recycled when not used.
+ *
+ * Addresses:
+ *
+ *  We use a 1:1 mapping mechanism between port address (0 based
+ *  index, actually) and the address. The USB stack knows about this.
+ *
+ *  USB Stack port number    4 (1 based)
+ *  WUSB code port index     3 (0 based)
+ *  USB Address             5 (2 based -- 0 is for default, 1 for root hub)
+ *
+ *  Now, because we don't use the concept as default address exactly
+ *  like the (wired) USB code does, we need to kind of skip it. So we
+ *  never take addresses from the urb->pipe, but from the
+ *  urb->dev->devnum, to make sure that we always have the right
+ *  destination address.
+ */
+#include <linux/atomic.h>
+#include <linux/bitmap.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+
+#include "wusbhc.h"
+#include "wa-hc.h"
+
+static int __rpipe_get_descr(struct wahc *wa,
+                            struct usb_rpipe_descriptor *descr, u16 index)
+{
+       ssize_t result;
+       struct device *dev = &wa->usb_iface->dev;
+
+       /* Get the RPIPE descriptor -- we cannot use the usb_get_descriptor()
+        * function because the arguments are different.
+        */
+       result = usb_control_msg(
+               wa->usb_dev, usb_rcvctrlpipe(wa->usb_dev, 0),
+               USB_REQ_GET_DESCRIPTOR,
+               USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_RPIPE,
+               USB_DT_RPIPE<<8, index, descr, sizeof(*descr),
+               USB_CTRL_GET_TIMEOUT);
+       if (result < 0) {
+               dev_err(dev, "rpipe %u: get descriptor failed: %d\n",
+                       index, (int)result);
+               goto error;
+       }
+       if (result < sizeof(*descr)) {
+               dev_err(dev, "rpipe %u: got short descriptor "
+                       "(%zd vs %zd bytes needed)\n",
+                       index, result, sizeof(*descr));
+               result = -EINVAL;
+               goto error;
+       }
+       result = 0;
+
+error:
+       return result;
+}
+
+/*
+ *
+ * The descriptor is assumed to be properly initialized (ie: you got
+ * it through __rpipe_get_descr()).
+ */
+static int __rpipe_set_descr(struct wahc *wa,
+                            struct usb_rpipe_descriptor *descr, u16 index)
+{
+       ssize_t result;
+       struct device *dev = &wa->usb_iface->dev;
+
+       /* we cannot use the usb_get_descriptor() function because the
+        * arguments are different.
+        */
+       result = usb_control_msg(
+               wa->usb_dev, usb_sndctrlpipe(wa->usb_dev, 0),
+               USB_REQ_SET_DESCRIPTOR,
+               USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_RPIPE,
+               USB_DT_RPIPE<<8, index, descr, sizeof(*descr),
+               USB_CTRL_SET_TIMEOUT);
+       if (result < 0) {
+               dev_err(dev, "rpipe %u: set descriptor failed: %d\n",
+                       index, (int)result);
+               goto error;
+       }
+       if (result < sizeof(*descr)) {
+               dev_err(dev, "rpipe %u: sent short descriptor "
+                       "(%zd vs %zd bytes required)\n",
+                       index, result, sizeof(*descr));
+               result = -EINVAL;
+               goto error;
+       }
+       result = 0;
+
+error:
+       return result;
+
+}
+
+static void rpipe_init(struct wa_rpipe *rpipe)
+{
+       kref_init(&rpipe->refcnt);
+       spin_lock_init(&rpipe->seg_lock);
+       INIT_LIST_HEAD(&rpipe->seg_list);
+       INIT_LIST_HEAD(&rpipe->list_node);
+}
+
+static unsigned rpipe_get_idx(struct wahc *wa, unsigned rpipe_idx)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&wa->rpipe_lock, flags);
+       rpipe_idx = find_next_zero_bit(wa->rpipe_bm, wa->rpipes, rpipe_idx);
+       if (rpipe_idx < wa->rpipes)
+               set_bit(rpipe_idx, wa->rpipe_bm);
+       spin_unlock_irqrestore(&wa->rpipe_lock, flags);
+
+       return rpipe_idx;
+}
+
+static void rpipe_put_idx(struct wahc *wa, unsigned rpipe_idx)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&wa->rpipe_lock, flags);
+       clear_bit(rpipe_idx, wa->rpipe_bm);
+       spin_unlock_irqrestore(&wa->rpipe_lock, flags);
+}
+
+void rpipe_destroy(struct kref *_rpipe)
+{
+       struct wa_rpipe *rpipe = container_of(_rpipe, struct wa_rpipe, refcnt);
+       u8 index = le16_to_cpu(rpipe->descr.wRPipeIndex);
+
+       if (rpipe->ep)
+               rpipe->ep->hcpriv = NULL;
+       rpipe_put_idx(rpipe->wa, index);
+       wa_put(rpipe->wa);
+       kfree(rpipe);
+}
+EXPORT_SYMBOL_GPL(rpipe_destroy);
+
+/*
+ * Locate an idle rpipe, create an structure for it and return it
+ *
+ * @wa   is referenced and unlocked
+ * @crs   enum rpipe_attr, required endpoint characteristics
+ *
+ * The rpipe can be used only sequentially (not in parallel).
+ *
+ * The rpipe is moved into the "ready" state.
+ */
+static int rpipe_get_idle(struct wa_rpipe **prpipe, struct wahc *wa, u8 crs,
+                         gfp_t gfp)
+{
+       int result;
+       unsigned rpipe_idx;
+       struct wa_rpipe *rpipe;
+       struct device *dev = &wa->usb_iface->dev;
+
+       rpipe = kzalloc(sizeof(*rpipe), gfp);
+       if (rpipe == NULL)
+               return -ENOMEM;
+       rpipe_init(rpipe);
+
+       /* Look for an idle pipe */
+       for (rpipe_idx = 0; rpipe_idx < wa->rpipes; rpipe_idx++) {
+               rpipe_idx = rpipe_get_idx(wa, rpipe_idx);
+               if (rpipe_idx >= wa->rpipes)    /* no more pipes :( */
+                       break;
+               result =  __rpipe_get_descr(wa, &rpipe->descr, rpipe_idx);
+               if (result < 0)
+                       dev_err(dev, "Can't get descriptor for rpipe %u: %d\n",
+                               rpipe_idx, result);
+               else if ((rpipe->descr.bmCharacteristics & crs) != 0)
+                       goto found;
+               rpipe_put_idx(wa, rpipe_idx);
+       }
+       *prpipe = NULL;
+       kfree(rpipe);
+       return -ENXIO;
+
+found:
+       set_bit(rpipe_idx, wa->rpipe_bm);
+       rpipe->wa = wa_get(wa);
+       *prpipe = rpipe;
+       return 0;
+}
+
+static int __rpipe_reset(struct wahc *wa, unsigned index)
+{
+       int result;
+       struct device *dev = &wa->usb_iface->dev;
+
+       result = usb_control_msg(
+               wa->usb_dev, usb_sndctrlpipe(wa->usb_dev, 0),
+               USB_REQ_RPIPE_RESET,
+               USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_RPIPE,
+               0, index, NULL, 0, USB_CTRL_SET_TIMEOUT);
+       if (result < 0)
+               dev_err(dev, "rpipe %u: reset failed: %d\n",
+                       index, result);
+       return result;
+}
+
+/*
+ * Fake companion descriptor for ep0
+ *
+ * See WUSB1.0[7.4.4], most of this is zero for bulk/int/ctl
+ */
+static struct usb_wireless_ep_comp_descriptor epc0 = {
+       .bLength = sizeof(epc0),
+       .bDescriptorType = USB_DT_WIRELESS_ENDPOINT_COMP,
+       .bMaxBurst = 1,
+       .bMaxSequence = 2,
+};
+
+/*
+ * Look for EP companion descriptor
+ *
+ * Get there, look for Inara in the endpoint's extra descriptors
+ */
+static struct usb_wireless_ep_comp_descriptor *rpipe_epc_find(
+               struct device *dev, struct usb_host_endpoint *ep)
+{
+       void *itr;
+       size_t itr_size;
+       struct usb_descriptor_header *hdr;
+       struct usb_wireless_ep_comp_descriptor *epcd;
+
+       if (ep->desc.bEndpointAddress == 0) {
+               epcd = &epc0;
+               goto out;
+       }
+       itr = ep->extra;
+       itr_size = ep->extralen;
+       epcd = NULL;
+       while (itr_size > 0) {
+               if (itr_size < sizeof(*hdr)) {
+                       dev_err(dev, "HW Bug? ep 0x%02x: extra descriptors "
+                               "at offset %zu: only %zu bytes left\n",
+                               ep->desc.bEndpointAddress,
+                               itr - (void *) ep->extra, itr_size);
+                       break;
+               }
+               hdr = itr;
+               if (hdr->bDescriptorType == USB_DT_WIRELESS_ENDPOINT_COMP) {
+                       epcd = itr;
+                       break;
+               }
+               if (hdr->bLength > itr_size) {
+                       dev_err(dev, "HW Bug? ep 0x%02x: extra descriptor "
+                               "at offset %zu (type 0x%02x) "
+                               "length %d but only %zu bytes left\n",
+                               ep->desc.bEndpointAddress,
+                               itr - (void *) ep->extra, hdr->bDescriptorType,
+                               hdr->bLength, itr_size);
+                       break;
+               }
+               itr += hdr->bLength;
+               itr_size -= hdr->bLength;
+       }
+out:
+       return epcd;
+}
+
+/*
+ * Aim an rpipe to its device & endpoint destination
+ *
+ * Make sure we change the address to unauthenticated if the device
+ * is WUSB and it is not authenticated.
+ */
+static int rpipe_aim(struct wa_rpipe *rpipe, struct wahc *wa,
+                    struct usb_host_endpoint *ep, struct urb *urb, gfp_t gfp)
+{
+       int result = -ENOMSG;   /* better code for lack of companion? */
+       struct device *dev = &wa->usb_iface->dev;
+       struct usb_device *usb_dev = urb->dev;
+       struct usb_wireless_ep_comp_descriptor *epcd;
+       u32 ack_window, epcd_max_sequence;
+       u8 unauth;
+
+       epcd = rpipe_epc_find(dev, ep);
+       if (epcd == NULL) {
+               dev_err(dev, "ep 0x%02x: can't find companion descriptor\n",
+                       ep->desc.bEndpointAddress);
+               goto error;
+       }
+       unauth = usb_dev->wusb && !usb_dev->authenticated ? 0x80 : 0;
+       __rpipe_reset(wa, le16_to_cpu(rpipe->descr.wRPipeIndex));
+       atomic_set(&rpipe->segs_available,
+               le16_to_cpu(rpipe->descr.wRequests));
+       /* FIXME: block allocation system; request with queuing and timeout */
+       /* FIXME: compute so seg_size > ep->maxpktsize */
+       rpipe->descr.wBlocks = cpu_to_le16(16);         /* given */
+       /* ep0 maxpktsize is 0x200 (WUSB1.0[4.8.1]) */
+       if (usb_endpoint_xfer_isoc(&ep->desc))
+               rpipe->descr.wMaxPacketSize = epcd->wOverTheAirPacketSize;
+       else
+               rpipe->descr.wMaxPacketSize = ep->desc.wMaxPacketSize;
+
+       rpipe->descr.hwa_bMaxBurst = max(min_t(unsigned int,
+                               epcd->bMaxBurst, 16U), 1U);
+       rpipe->descr.hwa_bDeviceInfoIndex =
+                       wusb_port_no_to_idx(urb->dev->portnum);
+       /* FIXME: use maximum speed as supported or recommended by device */
+       rpipe->descr.bSpeed = usb_pipeendpoint(urb->pipe) == 0 ?
+               UWB_PHY_RATE_53 : UWB_PHY_RATE_200;
+
+       dev_dbg(dev, "addr %u (0x%02x) rpipe #%u ep# %u speed %d\n",
+               urb->dev->devnum, urb->dev->devnum | unauth,
+               le16_to_cpu(rpipe->descr.wRPipeIndex),
+               usb_pipeendpoint(urb->pipe), rpipe->descr.bSpeed);
+
+       rpipe->descr.hwa_reserved = 0;
+
+       rpipe->descr.bEndpointAddress = ep->desc.bEndpointAddress;
+       /* FIXME: bDataSequence */
+       rpipe->descr.bDataSequence = 0;
+
+       /* start with base window of hwa_bMaxBurst bits starting at 0. */
+       ack_window = 0xFFFFFFFF >> (32 - rpipe->descr.hwa_bMaxBurst);
+       rpipe->descr.dwCurrentWindow = cpu_to_le32(ack_window);
+       epcd_max_sequence = max(min_t(unsigned int,
+                       epcd->bMaxSequence, 32U), 2U);
+       rpipe->descr.bMaxDataSequence = epcd_max_sequence - 1;
+       rpipe->descr.bInterval = ep->desc.bInterval;
+       if (usb_endpoint_xfer_isoc(&ep->desc))
+               rpipe->descr.bOverTheAirInterval = epcd->bOverTheAirInterval;
+       else
+               rpipe->descr.bOverTheAirInterval = 0;   /* 0 if not isoc */
+       /* FIXME: xmit power & preamble blah blah */
+       rpipe->descr.bmAttribute = (ep->desc.bmAttributes &
+                                       USB_ENDPOINT_XFERTYPE_MASK);
+       /* rpipe->descr.bmCharacteristics RO */
+       rpipe->descr.bmRetryOptions = (wa->wusb->retry_count & 0xF);
+       /* FIXME: use for assessing link quality? */
+       rpipe->descr.wNumTransactionErrors = 0;
+       result = __rpipe_set_descr(wa, &rpipe->descr,
+                                  le16_to_cpu(rpipe->descr.wRPipeIndex));
+       if (result < 0) {
+               dev_err(dev, "Cannot aim rpipe: %d\n", result);
+               goto error;
+       }
+       result = 0;
+error:
+       return result;
+}
+
+/*
+ * Check an aimed rpipe to make sure it points to where we want
+ *
+ * We use bit 19 of the Linux USB pipe bitmap for unauth vs auth
+ * space; when it is like that, we or 0x80 to make an unauth address.
+ */
+static int rpipe_check_aim(const struct wa_rpipe *rpipe, const struct wahc *wa,
+                          const struct usb_host_endpoint *ep,
+                          const struct urb *urb, gfp_t gfp)
+{
+       int result = 0;
+       struct device *dev = &wa->usb_iface->dev;
+       u8 portnum = wusb_port_no_to_idx(urb->dev->portnum);
+
+#define AIM_CHECK(rdf, val, text)                                      \
+       do {                                                            \
+               if (rpipe->descr.rdf != (val)) {                        \
+                       dev_err(dev,                                    \
+                               "rpipe aim discrepancy: " #rdf " " text "\n", \
+                               rpipe->descr.rdf, (val));               \
+                       result = -EINVAL;                               \
+                       WARN_ON(1);                                     \
+               }                                                       \
+       } while (0)
+       AIM_CHECK(hwa_bDeviceInfoIndex, portnum, "(%u vs %u)");
+       AIM_CHECK(bSpeed, usb_pipeendpoint(urb->pipe) == 0 ?
+                       UWB_PHY_RATE_53 : UWB_PHY_RATE_200,
+                 "(%u vs %u)");
+       AIM_CHECK(bEndpointAddress, ep->desc.bEndpointAddress, "(%u vs %u)");
+       AIM_CHECK(bInterval, ep->desc.bInterval, "(%u vs %u)");
+       AIM_CHECK(bmAttribute, ep->desc.bmAttributes & 0x03, "(%u vs %u)");
+#undef AIM_CHECK
+       return result;
+}
+
+#ifndef CONFIG_BUG
+#define CONFIG_BUG 0
+#endif
+
+/*
+ * Make sure there is an rpipe allocated for an endpoint
+ *
+ * If already allocated, we just refcount it; if not, we get an
+ * idle one, aim it to the right location and take it.
+ *
+ * Attaches to ep->hcpriv and rpipe->ep to ep.
+ */
+int rpipe_get_by_ep(struct wahc *wa, struct usb_host_endpoint *ep,
+                   struct urb *urb, gfp_t gfp)
+{
+       int result = 0;
+       struct device *dev = &wa->usb_iface->dev;
+       struct wa_rpipe *rpipe;
+       u8 eptype;
+
+       mutex_lock(&wa->rpipe_mutex);
+       rpipe = ep->hcpriv;
+       if (rpipe != NULL) {
+               if (CONFIG_BUG == 1) {
+                       result = rpipe_check_aim(rpipe, wa, ep, urb, gfp);
+                       if (result < 0)
+                               goto error;
+               }
+               __rpipe_get(rpipe);
+               dev_dbg(dev, "ep 0x%02x: reusing rpipe %u\n",
+                       ep->desc.bEndpointAddress,
+                       le16_to_cpu(rpipe->descr.wRPipeIndex));
+       } else {
+               /* hmm, assign idle rpipe, aim it */
+               result = -ENOBUFS;
+               eptype = ep->desc.bmAttributes & 0x03;
+               result = rpipe_get_idle(&rpipe, wa, 1 << eptype, gfp);
+               if (result < 0)
+                       goto error;
+               result = rpipe_aim(rpipe, wa, ep, urb, gfp);
+               if (result < 0) {
+                       rpipe_put(rpipe);
+                       goto error;
+               }
+               ep->hcpriv = rpipe;
+               rpipe->ep = ep;
+               __rpipe_get(rpipe);     /* for caching into ep->hcpriv */
+               dev_dbg(dev, "ep 0x%02x: using rpipe %u\n",
+                       ep->desc.bEndpointAddress,
+                       le16_to_cpu(rpipe->descr.wRPipeIndex));
+       }
+error:
+       mutex_unlock(&wa->rpipe_mutex);
+       return result;
+}
+
+/*
+ * Allocate the bitmap for each rpipe.
+ */
+int wa_rpipes_create(struct wahc *wa)
+{
+       wa->rpipes = le16_to_cpu(wa->wa_descr->wNumRPipes);
+       wa->rpipe_bm = kzalloc(BITS_TO_LONGS(wa->rpipes)*sizeof(unsigned long),
+                              GFP_KERNEL);
+       if (wa->rpipe_bm == NULL)
+               return -ENOMEM;
+       return 0;
+}
+
+void wa_rpipes_destroy(struct wahc *wa)
+{
+       struct device *dev = &wa->usb_iface->dev;
+
+       if (!bitmap_empty(wa->rpipe_bm, wa->rpipes)) {
+               WARN_ON(1);
+               dev_err(dev, "BUG: pipes not released on exit: %*pb\n",
+                       wa->rpipes, wa->rpipe_bm);
+       }
+       kfree(wa->rpipe_bm);
+}
+
+/*
+ * Release resources allocated for an endpoint
+ *
+ * If there is an associated rpipe to this endpoint, Abort any pending
+ * transfers and put it. If the rpipe ends up being destroyed,
+ * __rpipe_destroy() will cleanup ep->hcpriv.
+ *
+ * This is called before calling hcd->stop(), so you don't need to do
+ * anything else in there.
+ */
+void rpipe_ep_disable(struct wahc *wa, struct usb_host_endpoint *ep)
+{
+       struct wa_rpipe *rpipe;
+
+       mutex_lock(&wa->rpipe_mutex);
+       rpipe = ep->hcpriv;
+       if (rpipe != NULL) {
+               u16 index = le16_to_cpu(rpipe->descr.wRPipeIndex);
+
+               usb_control_msg(
+                       wa->usb_dev, usb_sndctrlpipe(wa->usb_dev, 0),
+                       USB_REQ_RPIPE_ABORT,
+                       USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_RPIPE,
+                       0, index, NULL, 0, USB_CTRL_SET_TIMEOUT);
+               rpipe_put(rpipe);
+       }
+       mutex_unlock(&wa->rpipe_mutex);
+}
+EXPORT_SYMBOL_GPL(rpipe_ep_disable);
+
+/* Clear the stalled status of an RPIPE. */
+void rpipe_clear_feature_stalled(struct wahc *wa, struct usb_host_endpoint *ep)
+{
+       struct wa_rpipe *rpipe;
+
+       mutex_lock(&wa->rpipe_mutex);
+       rpipe = ep->hcpriv;
+       if (rpipe != NULL) {
+               u16 index = le16_to_cpu(rpipe->descr.wRPipeIndex);
+
+               usb_control_msg(
+                       wa->usb_dev, usb_sndctrlpipe(wa->usb_dev, 0),
+                       USB_REQ_CLEAR_FEATURE,
+                       USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_RPIPE,
+                       RPIPE_STALL, index, NULL, 0, USB_CTRL_SET_TIMEOUT);
+       }
+       mutex_unlock(&wa->rpipe_mutex);
+}
+EXPORT_SYMBOL_GPL(rpipe_clear_feature_stalled);