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path: root/drivers/staging/wusbcore/wa-nep.c
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Diffstat (limited to 'drivers/staging/wusbcore/wa-nep.c')
-rw-r--r--drivers/staging/wusbcore/wa-nep.c289
1 files changed, 0 insertions, 289 deletions
diff --git a/drivers/staging/wusbcore/wa-nep.c b/drivers/staging/wusbcore/wa-nep.c
deleted file mode 100644
index 5f0656db5482..000000000000
--- a/drivers/staging/wusbcore/wa-nep.c
+++ /dev/null
@@ -1,289 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * WUSB Wire Adapter: Control/Data Streaming Interface (WUSB[8])
- * Notification EndPoint support
- *
- * Copyright (C) 2006 Intel Corporation
- * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
- *
- * This part takes care of getting the notification from the hw
- * only and dispatching through wusbwad into
- * wa_notif_dispatch. Handling is done there.
- *
- * WA notifications are limited in size; most of them are three or
- * four bytes long, and the longest is the HWA Device Notification,
- * which would not exceed 38 bytes (DNs are limited in payload to 32
- * bytes plus 3 bytes header (WUSB1.0[7.6p2]), plus 3 bytes HWA
- * header (WUSB1.0[8.5.4.2]).
- *
- * It is not clear if more than one Device Notification can be packed
- * in a HWA Notification, I assume no because of the wording in
- * WUSB1.0[8.5.4.2]. In any case, the bigger any notification could
- * get is 256 bytes (as the bLength field is a byte).
- *
- * So what we do is we have this buffer and read into it; when a
- * notification arrives we schedule work to a specific, single thread
- * workqueue (so notifications are serialized) and copy the
- * notification data. After scheduling the work, we rearm the read from
- * the notification endpoint.
- *
- * Entry points here are:
- *
- * wa_nep_[create|destroy]() To initialize/release this subsystem
- *
- * wa_nep_cb() Callback for the notification
- * endpoint; when data is ready, this
- * does the dispatching.
- */
-#include <linux/workqueue.h>
-#include <linux/ctype.h>
-#include <linux/slab.h>
-
-#include "wa-hc.h"
-#include "wusbhc.h"
-
-/* Structure for queueing notifications to the workqueue */
-struct wa_notif_work {
- struct work_struct work;
- struct wahc *wa;
- size_t size;
- u8 data[];
-};
-
-/*
- * Process incoming notifications from the WA's Notification EndPoint
- * [the wuswad daemon, basically]
- *
- * @_nw: Pointer to a descriptor which has the pointer to the
- * @wa, the size of the buffer and the work queue
- * structure (so we can free all when done).
- * @returns 0 if ok, < 0 errno code on error.
- *
- * All notifications follow the same format; they need to start with a
- * 'struct wa_notif_hdr' header, so it is easy to parse through
- * them. We just break the buffer in individual notifications (the
- * standard doesn't say if it can be done or is forbidden, so we are
- * cautious) and dispatch each.
- *
- * So the handling layers are is:
- *
- * WA specific notification (from NEP)
- * Device Notification Received -> wa_handle_notif_dn()
- * WUSB Device notification generic handling
- * BPST Adjustment -> wa_handle_notif_bpst_adj()
- * ... -> ...
- *
- * @wa has to be referenced
- */
-static void wa_notif_dispatch(struct work_struct *ws)
-{
- void *itr;
- u8 missing = 0;
- struct wa_notif_work *nw = container_of(ws, struct wa_notif_work,
- work);
- struct wahc *wa = nw->wa;
- struct wa_notif_hdr *notif_hdr;
- size_t size;
-
- struct device *dev = &wa->usb_iface->dev;
-
-#if 0
- /* FIXME: need to check for this??? */
- if (usb_hcd->state == HC_STATE_QUIESCING) /* Going down? */
- goto out; /* screw it */
-#endif
- atomic_dec(&wa->notifs_queued); /* Throttling ctl */
- size = nw->size;
- itr = nw->data;
-
- while (size) {
- if (size < sizeof(*notif_hdr)) {
- missing = sizeof(*notif_hdr) - size;
- goto exhausted_buffer;
- }
- notif_hdr = itr;
- if (size < notif_hdr->bLength)
- goto exhausted_buffer;
- itr += notif_hdr->bLength;
- size -= notif_hdr->bLength;
- /* Dispatch the notification [don't use itr or size!] */
- switch (notif_hdr->bNotifyType) {
- case HWA_NOTIF_DN: {
- struct hwa_notif_dn *hwa_dn;
- hwa_dn = container_of(notif_hdr, struct hwa_notif_dn,
- hdr);
- wusbhc_handle_dn(wa->wusb, hwa_dn->bSourceDeviceAddr,
- hwa_dn->dndata,
- notif_hdr->bLength - sizeof(*hwa_dn));
- break;
- }
- case WA_NOTIF_TRANSFER:
- wa_handle_notif_xfer(wa, notif_hdr);
- break;
- case HWA_NOTIF_BPST_ADJ:
- break; /* no action needed for BPST ADJ. */
- case DWA_NOTIF_RWAKE:
- case DWA_NOTIF_PORTSTATUS:
- /* FIXME: unimplemented WA NOTIFs */
- /* fallthru */
- default:
- dev_err(dev, "HWA: unknown notification 0x%x, "
- "%zu bytes; discarding\n",
- notif_hdr->bNotifyType,
- (size_t)notif_hdr->bLength);
- break;
- }
- }
-out:
- wa_put(wa);
- kfree(nw);
- return;
-
- /* THIS SHOULD NOT HAPPEN
- *
- * Buffer exahusted with partial data remaining; just warn and
- * discard the data, as this should not happen.
- */
-exhausted_buffer:
- dev_warn(dev, "HWA: device sent short notification, "
- "%d bytes missing; discarding %d bytes.\n",
- missing, (int)size);
- goto out;
-}
-
-/*
- * Deliver incoming WA notifications to the wusbwa workqueue
- *
- * @wa: Pointer the Wire Adapter Controller Data Streaming
- * instance (part of an 'struct usb_hcd').
- * @size: Size of the received buffer
- * @returns 0 if ok, < 0 errno code on error.
- *
- * The input buffer is @wa->nep_buffer, with @size bytes
- * (guaranteed to fit in the allocated space,
- * @wa->nep_buffer_size).
- */
-static int wa_nep_queue(struct wahc *wa, size_t size)
-{
- int result = 0;
- struct device *dev = &wa->usb_iface->dev;
- struct wa_notif_work *nw;
-
- /* dev_fnstart(dev, "(wa %p, size %zu)\n", wa, size); */
- BUG_ON(size > wa->nep_buffer_size);
- if (size == 0)
- goto out;
- if (atomic_read(&wa->notifs_queued) > 200) {
- if (printk_ratelimit())
- dev_err(dev, "Too many notifications queued, "
- "throttling back\n");
- goto out;
- }
- nw = kzalloc(sizeof(*nw) + size, GFP_ATOMIC);
- if (nw == NULL) {
- if (printk_ratelimit())
- dev_err(dev, "No memory to queue notification\n");
- result = -ENOMEM;
- goto out;
- }
- INIT_WORK(&nw->work, wa_notif_dispatch);
- nw->wa = wa_get(wa);
- nw->size = size;
- memcpy(nw->data, wa->nep_buffer, size);
- atomic_inc(&wa->notifs_queued); /* Throttling ctl */
- queue_work(wusbd, &nw->work);
-out:
- /* dev_fnend(dev, "(wa %p, size %zu) = result\n", wa, size, result); */
- return result;
-}
-
-/*
- * Callback for the notification event endpoint
- *
- * Check's that everything is fine and then passes the data to be
- * queued to the workqueue.
- */
-static void wa_nep_cb(struct urb *urb)
-{
- int result;
- struct wahc *wa = urb->context;
- struct device *dev = &wa->usb_iface->dev;
-
- switch (result = urb->status) {
- case 0:
- result = wa_nep_queue(wa, urb->actual_length);
- if (result < 0)
- dev_err(dev, "NEP: unable to process notification(s): "
- "%d\n", result);
- break;
- case -ECONNRESET: /* Not an error, but a controlled situation; */
- case -ENOENT: /* (we killed the URB)...so, no broadcast */
- case -ESHUTDOWN:
- dev_dbg(dev, "NEP: going down %d\n", urb->status);
- goto out;
- default: /* On general errors, we retry unless it gets ugly */
- if (edc_inc(&wa->nep_edc, EDC_MAX_ERRORS,
- EDC_ERROR_TIMEFRAME)) {
- dev_err(dev, "NEP: URB max acceptable errors "
- "exceeded, resetting device\n");
- wa_reset_all(wa);
- goto out;
- }
- dev_err(dev, "NEP: URB error %d\n", urb->status);
- }
- result = wa_nep_arm(wa, GFP_ATOMIC);
- if (result < 0) {
- dev_err(dev, "NEP: cannot submit URB: %d\n", result);
- wa_reset_all(wa);
- }
-out:
- return;
-}
-
-/*
- * Initialize @wa's notification and event's endpoint stuff
- *
- * This includes the allocating the read buffer, the context ID
- * allocation bitmap, the URB and submitting the URB.
- */
-int wa_nep_create(struct wahc *wa, struct usb_interface *iface)
-{
- int result;
- struct usb_endpoint_descriptor *epd;
- struct usb_device *usb_dev = interface_to_usbdev(iface);
- struct device *dev = &iface->dev;
-
- edc_init(&wa->nep_edc);
- epd = &iface->cur_altsetting->endpoint[0].desc;
- wa->nep_buffer_size = 1024;
- wa->nep_buffer = kmalloc(wa->nep_buffer_size, GFP_KERNEL);
- if (!wa->nep_buffer)
- goto error_nep_buffer;
- wa->nep_urb = usb_alloc_urb(0, GFP_KERNEL);
- if (wa->nep_urb == NULL)
- goto error_urb_alloc;
- usb_fill_int_urb(wa->nep_urb, usb_dev,
- usb_rcvintpipe(usb_dev, epd->bEndpointAddress),
- wa->nep_buffer, wa->nep_buffer_size,
- wa_nep_cb, wa, epd->bInterval);
- result = wa_nep_arm(wa, GFP_KERNEL);
- if (result < 0) {
- dev_err(dev, "Cannot submit notification URB: %d\n", result);
- goto error_nep_arm;
- }
- return 0;
-
-error_nep_arm:
- usb_free_urb(wa->nep_urb);
-error_urb_alloc:
- kfree(wa->nep_buffer);
-error_nep_buffer:
- return -ENOMEM;
-}
-
-void wa_nep_destroy(struct wahc *wa)
-{
- wa_nep_disarm(wa);
- usb_free_urb(wa->nep_urb);
- kfree(wa->nep_buffer);
-}