1 files changed, 303 insertions, 0 deletions
diff --git a/drivers/staging/wusbcore/mmc.c b/drivers/staging/wusbcore/mmc.c
new file mode 100644
index 000000000000..881e1f20d718
--- /dev/null
+++ b/drivers/staging/wusbcore/mmc.c
@@ -0,0 +1,303 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * WUSB Wire Adapter: Control/Data Streaming Interface (WUSB[8])
+ * MMC (Microscheduled Management Command) handling
+ *
+ * Copyright (C) 2005-2006 Intel Corporation
+ * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
+ *
+ * WUIEs and MMC IEs...well, they are almost the same at the end. MMC
+ * IEs are Wireless USB IEs that go into the MMC period...[what is
+ * that? look in Design-overview.txt].
+ *
+ *
+ * This is a simple subsystem to keep track of which IEs are being
+ * sent by the host in the MMC period.
+ *
+ * For each WUIE we ask to send, we keep it in an array, so we can
+ * request its removal later, or replace the content. They are tracked
+ * by pointer, so be sure to use the same pointer if you want to
+ * remove it or update the contents.
+ *
+ * FIXME:
+ *  - add timers that autoremove intervalled IEs?
+ */
+#include <linux/slab.h>
+#include <linux/export.h>
+#include "include/wusb.h"
+#include "wusbhc.h"
+
+/* Initialize the MMCIEs handling mechanism */
+int wusbhc_mmcie_create(struct wusbhc *wusbhc)
+{
+	u8 mmcies = wusbhc->mmcies_max;
+	wusbhc->mmcie = kcalloc(mmcies, sizeof(wusbhc->mmcie[0]), GFP_KERNEL);
+	if (wusbhc->mmcie == NULL)
+		return -ENOMEM;
+	mutex_init(&wusbhc->mmcie_mutex);
+	return 0;
+}
+
+/* Release resources used by the MMCIEs handling mechanism */
+void wusbhc_mmcie_destroy(struct wusbhc *wusbhc)
+{
+	kfree(wusbhc->mmcie);
+}
+
+/*
+ * Add or replace an MMC Wireless USB IE.
+ *
+ * @interval:    See WUSB1.0[8.5.3.1]
+ * @repeat_cnt:  See WUSB1.0[8.5.3.1]
+ * @handle:      See WUSB1.0[8.5.3.1]
+ * @wuie:        Pointer to the header of the WUSB IE data to add.
+ *               MUST BE allocated in a kmalloc buffer (no stack or
+ *               vmalloc).
+ *               THE CALLER ALWAYS OWNS THE POINTER (we don't free it
+ *               on remove, we just forget about it).
+ * @returns:     0 if ok, < 0 errno code on error.
+ *
+ * Goes over the *whole* @wusbhc->mmcie array looking for (a) the
+ * first free spot and (b) if @wuie is already in the array (aka:
+ * transmitted in the MMCs) the spot were it is.
+ *
+ * If present, we "overwrite it" (update).
+ *
+ *
+ * NOTE: Need special ordering rules -- see below WUSB1.0 Table 7-38.
+ *       The host uses the handle as the 'sort' index. We
+ *       allocate the last one always for the WUIE_ID_HOST_INFO, and
+ *       the rest, first come first serve in inverse order.
+ *
+ *       Host software must make sure that it adds the other IEs in
+ *       the right order... the host hardware is responsible for
+ *       placing the WCTA IEs in the right place with the other IEs
+ *       set by host software.
+ *
+ * NOTE: we can access wusbhc->wa_descr without locking because it is
+ *       read only.
+ */
+int wusbhc_mmcie_set(struct wusbhc *wusbhc, u8 interval, u8 repeat_cnt,
+		     struct wuie_hdr *wuie)
+{
+	int result = -ENOBUFS;
+	unsigned handle, itr;
+
+	/* Search a handle, taking into account the ordering */
+	mutex_lock(&wusbhc->mmcie_mutex);
+	switch (wuie->bIEIdentifier) {
+	case WUIE_ID_HOST_INFO:
+		/* Always last */
+		handle = wusbhc->mmcies_max - 1;
+		break;
+	case WUIE_ID_ISOCH_DISCARD:
+		dev_err(wusbhc->dev, "Special ordering case for WUIE ID 0x%x "
+			"unimplemented\n", wuie->bIEIdentifier);
+		result = -ENOSYS;
+		goto error_unlock;
+	default:
+		/* search for it or find the last empty slot */
+		handle = ~0;
+		for (itr = 0; itr < wusbhc->mmcies_max - 1; itr++) {
+			if (wusbhc->mmcie[itr] == wuie) {
+				handle = itr;
+				break;
+			}
+			if (wusbhc->mmcie[itr] == NULL)
+				handle = itr;
+		}
+		if (handle == ~0)
+			goto error_unlock;
+	}
+	result = (wusbhc->mmcie_add)(wusbhc, interval, repeat_cnt, handle,
+				     wuie);
+	if (result >= 0)
+		wusbhc->mmcie[handle] = wuie;
+error_unlock:
+	mutex_unlock(&wusbhc->mmcie_mutex);
+	return result;
+}
+EXPORT_SYMBOL_GPL(wusbhc_mmcie_set);
+
+/*
+ * Remove an MMC IE previously added with wusbhc_mmcie_set()
+ *
+ * @wuie	Pointer used to add the WUIE
+ */
+void wusbhc_mmcie_rm(struct wusbhc *wusbhc, struct wuie_hdr *wuie)
+{
+	int result;
+	unsigned handle, itr;
+
+	mutex_lock(&wusbhc->mmcie_mutex);
+	for (itr = 0; itr < wusbhc->mmcies_max; itr++) {
+		if (wusbhc->mmcie[itr] == wuie) {
+			handle = itr;
+			goto found;
+		}
+	}
+	mutex_unlock(&wusbhc->mmcie_mutex);
+	return;
+
+found:
+	result = (wusbhc->mmcie_rm)(wusbhc, handle);
+	if (result == 0)
+		wusbhc->mmcie[itr] = NULL;
+	mutex_unlock(&wusbhc->mmcie_mutex);
+}
+EXPORT_SYMBOL_GPL(wusbhc_mmcie_rm);
+
+static int wusbhc_mmc_start(struct wusbhc *wusbhc)
+{
+	int ret;
+
+	mutex_lock(&wusbhc->mutex);
+	ret = wusbhc->start(wusbhc);
+	if (ret >= 0)
+		wusbhc->active = 1;
+	mutex_unlock(&wusbhc->mutex);
+
+	return ret;
+}
+
+static void wusbhc_mmc_stop(struct wusbhc *wusbhc)
+{
+	mutex_lock(&wusbhc->mutex);
+	wusbhc->active = 0;
+	wusbhc->stop(wusbhc, WUSB_CHANNEL_STOP_DELAY_MS);
+	mutex_unlock(&wusbhc->mutex);
+}
+
+/*
+ * wusbhc_start - start transmitting MMCs and accepting connections
+ * @wusbhc: the HC to start
+ *
+ * Establishes a cluster reservation, enables device connections, and
+ * starts MMCs with appropriate DNTS parameters.
+ */
+int wusbhc_start(struct wusbhc *wusbhc)
+{
+	int result;
+	struct device *dev = wusbhc->dev;
+
+	WARN_ON(wusbhc->wuie_host_info != NULL);
+	BUG_ON(wusbhc->uwb_rc == NULL);
+
+	result = wusbhc_rsv_establish(wusbhc);
+	if (result < 0) {
+		dev_err(dev, "cannot establish cluster reservation: %d\n",
+			result);
+		goto error_rsv_establish;
+	}
+
+	result = wusbhc_devconnect_start(wusbhc);
+	if (result < 0) {
+		dev_err(dev, "error enabling device connections: %d\n",
+			result);
+		goto error_devconnect_start;
+	}
+
+	result = wusbhc_sec_start(wusbhc);
+	if (result < 0) {
+		dev_err(dev, "error starting security in the HC: %d\n",
+			result);
+		goto error_sec_start;
+	}
+
+	result = wusbhc->set_num_dnts(wusbhc, wusbhc->dnts_interval,
+		wusbhc->dnts_num_slots);
+	if (result < 0) {
+		dev_err(dev, "Cannot set DNTS parameters: %d\n", result);
+		goto error_set_num_dnts;
+	}
+	result = wusbhc_mmc_start(wusbhc);
+	if (result < 0) {
+		dev_err(dev, "error starting wusbch: %d\n", result);
+		goto error_wusbhc_start;
+	}
+
+	return 0;
+
+error_wusbhc_start:
+	wusbhc_sec_stop(wusbhc);
+error_set_num_dnts:
+error_sec_start:
+	wusbhc_devconnect_stop(wusbhc);
+error_devconnect_start:
+	wusbhc_rsv_terminate(wusbhc);
+error_rsv_establish:
+	return result;
+}
+
+/*
+ * wusbhc_stop - stop transmitting MMCs
+ * @wusbhc: the HC to stop
+ *
+ * Stops the WUSB channel and removes the cluster reservation.
+ */
+void wusbhc_stop(struct wusbhc *wusbhc)
+{
+	wusbhc_mmc_stop(wusbhc);
+	wusbhc_sec_stop(wusbhc);
+	wusbhc_devconnect_stop(wusbhc);
+	wusbhc_rsv_terminate(wusbhc);
+}
+
+/*
+ * Set/reset/update a new CHID
+ *
+ * Depending on the previous state of the MMCs, start, stop or change
+ * the sent MMC. This effectively switches the host controller on and
+ * off (radio wise).
+ */
+int wusbhc_chid_set(struct wusbhc *wusbhc, const struct wusb_ckhdid *chid)
+{
+	int result = 0;
+
+	if (memcmp(chid, &wusb_ckhdid_zero, sizeof(*chid)) == 0)
+		chid = NULL;
+
+	mutex_lock(&wusbhc->mutex);
+	if (chid) {
+		if (wusbhc->active) {
+			mutex_unlock(&wusbhc->mutex);
+			return -EBUSY;
+		}
+		wusbhc->chid = *chid;
+	}
+
+	/* register with UWB if we haven't already since we are about to start
+	    the radio. */
+	if ((chid) && (wusbhc->uwb_rc == NULL)) {
+		wusbhc->uwb_rc = uwb_rc_get_by_grandpa(wusbhc->dev->parent);
+		if (wusbhc->uwb_rc == NULL) {
+			result = -ENODEV;
+			dev_err(wusbhc->dev,
+				"Cannot get associated UWB Host Controller\n");
+			goto error_rc_get;
+		}
+
+		result = wusbhc_pal_register(wusbhc);
+		if (result < 0) {
+			dev_err(wusbhc->dev, "Cannot register as a UWB PAL\n");
+			goto error_pal_register;
+		}
+	}
+	mutex_unlock(&wusbhc->mutex);
+
+	if (chid)
+		result = uwb_radio_start(&wusbhc->pal);
+	else if (wusbhc->uwb_rc)
+		uwb_radio_stop(&wusbhc->pal);
+
+	return result;
+
+error_pal_register:
+	uwb_rc_put(wusbhc->uwb_rc);
+	wusbhc->uwb_rc = NULL;
+error_rc_get:
+	mutex_unlock(&wusbhc->mutex);
+
+	return result;
+}
+EXPORT_SYMBOL_GPL(wusbhc_chid_set);