wusb: add the Wireless USB include files.

Common header files derived from the WUSB 1.0 specification.
Signed-off-by: David Vrabel <david.vrabel@csr.com>

include/linux/usb/wusb-wa.h

+/*
+ * Wireless USB Wire Adapter constants and structures.
+ *
+ * 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
+ * FIXME: organize properly, group logically
+ *
+ * All the event structures are defined in uwb/spec.h, as they are
+ * common to the WHCI and WUSB radio control interfaces.
+ *
+ * References:
+ *   [WUSB] Wireless Universal Serial Bus Specification, revision 1.0, ch8
+ */
+#ifndef __LINUX_USB_WUSB_WA_H
+#define __LINUX_USB_WUSB_WA_H
+
+/**
+ * Radio Command Request for the Radio Control Interface
+ *
+ * Radio Control Interface command and event codes are the same as
+ * WHCI, and listed in include/linux/uwb.h:UWB_RC_{CMD,EVT}_*
+ */
+enum {
+	WA_EXEC_RC_CMD = 40,	/* Radio Control command Request */
+};
+
+/* Wireless Adapter Requests ([WUSB] table 8-51) */
+enum {
+	WUSB_REQ_ADD_MMC_IE     = 20,
+	WUSB_REQ_REMOVE_MMC_IE  = 21,
+	WUSB_REQ_SET_NUM_DNTS   = 22,
+	WUSB_REQ_SET_CLUSTER_ID = 23,
+	WUSB_REQ_SET_DEV_INFO   = 24,
+	WUSB_REQ_GET_TIME       = 25,
+	WUSB_REQ_SET_STREAM_IDX = 26,
+	WUSB_REQ_SET_WUSB_MAS   = 27,
+};
+
+
+/* Wireless Adapter WUSB Channel Time types ([WUSB] table 8-52) */
+enum {
+	WUSB_TIME_ADJ   = 0,
+	WUSB_TIME_BPST  = 1,
+	WUSB_TIME_WUSB  = 2,
+};
+
+enum {
+	WA_ENABLE = 0x01,
+	WA_RESET = 0x02,
+	RPIPE_PAUSE = 0x1,
+};
+
+/* Responses from Get Status request ([WUSB] section 8.3.1.6) */
+enum {
+	WA_STATUS_ENABLED = 0x01,
+	WA_STATUS_RESETTING = 0x02
+};
+
+enum rpipe_crs {
+	RPIPE_CRS_CTL = 0x01,
+	RPIPE_CRS_ISO = 0x02,
+	RPIPE_CRS_BULK = 0x04,
+	RPIPE_CRS_INTR = 0x08
+};
+
+/**
+ * RPipe descriptor ([WUSB] section 8.5.2.11)
+ *
+ * FIXME: explain rpipes
+ */
+struct usb_rpipe_descriptor {
+	u8 	bLength;
+	u8	bDescriptorType;
+	__le16  wRPipeIndex;
+	__le16	wRequests;
+	__le16	wBlocks;		/* rw if 0 */
+	__le16	wMaxPacketSize;		/* rw? */
+	u8	bHSHubAddress;		/* reserved: 0 */
+	u8	bHSHubPort;		/* ??? FIXME ??? */
+	u8	bSpeed;			/* rw: xfer rate 'enum uwb_phy_rate' */
+	u8	bDeviceAddress;		/* rw: Target device address */
+	u8	bEndpointAddress;	/* rw: Target EP address */
+	u8	bDataSequence;		/* ro: Current Data sequence */
+	__le32	dwCurrentWindow;	/* ro */
+	u8	bMaxDataSequence;	/* ro?: max supported seq */
+	u8	bInterval;		/* rw:  */
+	u8	bOverTheAirInterval;	/* rw:  */
+	u8	bmAttribute;		/* ro?  */
+	u8	bmCharacteristics;	/* ro? enum rpipe_attr, supported xsactions */
+	u8	bmRetryOptions;		/* rw? */
+	__le16	wNumTransactionErrors;	/* rw */
+} __attribute__ ((packed));
+
+/**
+ * Wire Adapter Notification types ([WUSB] sections 8.4.5 & 8.5.4)
+ *
+ * These are the notifications coming on the notification endpoint of
+ * an HWA and a DWA.
+ */
+enum wa_notif_type {
+	DWA_NOTIF_RWAKE = 0x91,
+	DWA_NOTIF_PORTSTATUS = 0x92,
+	WA_NOTIF_TRANSFER = 0x93,
+	HWA_NOTIF_BPST_ADJ = 0x94,
+	HWA_NOTIF_DN = 0x95,
+};
+
+/**
+ * Wire Adapter notification header
+ *
+ * Notifications coming from a wire adapter use a common header
+ * defined in [WUSB] sections 8.4.5 & 8.5.4.
+ */
+struct wa_notif_hdr {
+	u8 bLength;
+	u8 bNotifyType;			/* enum wa_notif_type */
+} __attribute__((packed));
+
+/**
+ * HWA DN Received notification [(WUSB] section 8.5.4.2)
+ *
+ * The DNData is specified in WUSB1.0[7.6]. For each device
+ * notification we received, we just need to dispatch it.
+ *
+ * @dndata:  this is really an array of notifications, but all start
+ *           with the same header.
+ */
+struct hwa_notif_dn {
+	struct wa_notif_hdr hdr;
+	u8 bSourceDeviceAddr;		/* from errata 2005/07 */
+	u8 bmAttributes;
+	struct wusb_dn_hdr dndata[];
+} __attribute__((packed));
+
+/* [WUSB] section 8.3.3 */
+enum wa_xfer_type {
+	WA_XFER_TYPE_CTL = 0x80,
+	WA_XFER_TYPE_BI = 0x81,		/* bulk/interrupt */
+	WA_XFER_TYPE_ISO = 0x82,
+	WA_XFER_RESULT = 0x83,
+	WA_XFER_ABORT = 0x84,
+};
+
+/* [WUSB] section 8.3.3 */
+struct wa_xfer_hdr {
+	u8 bLength;			/* 0x18 */
+	u8 bRequestType;		/* 0x80 WA_REQUEST_TYPE_CTL */
+	__le16 wRPipe;			/* RPipe index */
+	__le32 dwTransferID;		/* Host-assigned ID */
+	__le32 dwTransferLength;	/* Length of data to xfer */
+	u8 bTransferSegment;
+} __attribute__((packed));
+
+struct wa_xfer_ctl {
+	struct wa_xfer_hdr hdr;
+	u8 bmAttribute;
+	__le16 wReserved;
+	struct usb_ctrlrequest baSetupData;
+} __attribute__((packed));
+
+struct wa_xfer_bi {
+	struct wa_xfer_hdr hdr;
+	u8 bReserved;
+	__le16 wReserved;
+} __attribute__((packed));
+
+struct wa_xfer_hwaiso {
+	struct wa_xfer_hdr hdr;
+	u8 bReserved;
+	__le16 wPresentationTime;
+	__le32 dwNumOfPackets;
+	/* FIXME: u8 pktdata[]? */
+} __attribute__((packed));
+
+/* [WUSB] section 8.3.3.5 */
+struct wa_xfer_abort {
+	u8 bLength;
+	u8 bRequestType;
+	__le16 wRPipe;			/* RPipe index */
+	__le32 dwTransferID;		/* Host-assigned ID */
+} __attribute__((packed));
+
+/**
+ * WA Transfer Complete notification ([WUSB] section 8.3.3.3)
+ *
+ */
+struct wa_notif_xfer {
+	struct wa_notif_hdr hdr;
+	u8 bEndpoint;
+	u8 Reserved;
+} __attribute__((packed));
+
+/** Transfer result basic codes [WUSB] table 8-15 */
+enum {
+	WA_XFER_STATUS_SUCCESS,
+	WA_XFER_STATUS_HALTED,
+	WA_XFER_STATUS_DATA_BUFFER_ERROR,
+	WA_XFER_STATUS_BABBLE,
+	WA_XFER_RESERVED,
+	WA_XFER_STATUS_NOT_FOUND,
+	WA_XFER_STATUS_INSUFFICIENT_RESOURCE,
+	WA_XFER_STATUS_TRANSACTION_ERROR,
+	WA_XFER_STATUS_ABORTED,
+	WA_XFER_STATUS_RPIPE_NOT_READY,
+	WA_XFER_INVALID_FORMAT,
+	WA_XFER_UNEXPECTED_SEGMENT_NUMBER,
+	WA_XFER_STATUS_RPIPE_TYPE_MISMATCH,
+};
+
+/** [WUSB] section 8.3.3.4 */
+struct wa_xfer_result {
+	struct wa_notif_hdr hdr;
+	__le32 dwTransferID;
+	__le32 dwTransferLength;
+	u8     bTransferSegment;
+	u8     bTransferStatus;
+	__le32 dwNumOfPackets;
+} __attribute__((packed));
+
+/**
+ * Wire Adapter Class Descriptor ([WUSB] section 8.5.2.7).
+ *
+ * NOTE: u16 fields are read Little Endian from the hardware.
+ *
+ * @bNumPorts is the original max number of devices that the host can
+ *            connect; we might chop this so the stack can handle
+ *            it. In case you need to access it, use wusbhc->ports_max
+ *            if it is a Wireless USB WA.
+ */
+struct usb_wa_descriptor {
+	u8	bLength;
+	u8	bDescriptorType;
+	u16	bcdWAVersion;
+	u8	bNumPorts;		/* don't use!! */
+	u8	bmAttributes;		/* Reserved == 0 */
+	u16	wNumRPipes;
+	u16	wRPipeMaxBlock;
+	u8	bRPipeBlockSize;
+	u8	bPwrOn2PwrGood;
+	u8	bNumMMCIEs;
+	u8	DeviceRemovable;	/* FIXME: in DWA this is up to 16 bytes */
+} __attribute__((packed));
+
+/**
+ * HWA Device Information Buffer (WUSB1.0[T8.54])
+ */
+struct hwa_dev_info {
+	u8	bmDeviceAvailability[32];       /* FIXME: ignored for now */
+	u8	bDeviceAddress;
+	__le16	wPHYRates;
+	u8	bmDeviceAttribute;
+} __attribute__((packed));
+
+#endif /* #ifndef __LINUX_USB_WUSB_WA_H */

include/linux/usb/wusb.h

+/*
+ * Wireless USB Standard Definitions
+ * Event Size Tables
+ *
+ * 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
+ * FIXME: organize properly, group logically
+ *
+ * All the event structures are defined in uwb/spec.h, as they are
+ * common to the WHCI and WUSB radio control interfaces.
+ */
+
+#ifndef __WUSB_H__
+#define __WUSB_H__
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/uwb/spec.h>
+#include <linux/usb/ch9.h>
+#include <linux/param.h>
+
+/**
+ * WUSB Information Element header
+ *
+ * I don't know why, they decided to make it different to the MBOA MAC
+ * IE Header; beats me.
+ */
+struct wuie_hdr {
+	u8 bLength;
+	u8 bIEIdentifier;
+} __attribute__((packed));
+
+enum {
+	WUIE_ID_WCTA = 0x80,
+	WUIE_ID_CONNECTACK,
+	WUIE_ID_HOST_INFO,
+	WUIE_ID_CHANGE_ANNOUNCE,
+	WUIE_ID_DEVICE_DISCONNECT,
+	WUIE_ID_HOST_DISCONNECT,
+	WUIE_ID_KEEP_ALIVE = 0x89,
+	WUIE_ID_ISOCH_DISCARD,
+	WUIE_ID_RESET_DEVICE,
+};
+
+/**
+ * Maximum number of array elements in a WUSB IE.
+ *
+ * WUSB1.0[7.5 before table 7-38] says that in WUSB IEs that
+ * are "arrays" have to limited to 4 elements. So we define it
+ * like that to ease up and submit only the neeed size.
+ */
+#define WUIE_ELT_MAX 4
+
+/**
+ * Wrapper for the data that defines a CHID, a CDID or a CK
+ *
+ * WUSB defines that CHIDs, CDIDs and CKs are a 16 byte string of
+ * data. In order to avoid confusion and enforce types, we wrap it.
+ *
+ * Make it packed, as we use it in some hw defintions.
+ */
+struct wusb_ckhdid {
+	u8 data[16];
+} __attribute__((packed));
+
+const static
+struct wusb_ckhdid wusb_ckhdid_zero = { .data = { 0 } };
+
+#define WUSB_CKHDID_STRSIZE (3 * sizeof(struct wusb_ckhdid) + 1)
+
+/**
+ * WUSB IE: Host Information (WUSB1.0[7.5.2])
+ *
+ * Used to provide information about the host to the Wireless USB
+ * devices in range (CHID can be used as an ASCII string).
+ */
+struct wuie_host_info {
+	struct wuie_hdr hdr;
+	__le16 attributes;
+	struct wusb_ckhdid CHID;
+} __attribute__((packed));
+
+/**
+ * WUSB IE: Connect Ack (WUSB1.0[7.5.1])
+ *
+ * Used to acknowledge device connect requests. See note for
+ * WUIE_ELT_MAX.
+ */
+struct wuie_connect_ack {
+	struct wuie_hdr hdr;
+	struct {
+		struct wusb_ckhdid CDID;
+		u8 bDeviceAddress;	/* 0 means unused */
+		u8 bReserved;
+	} blk[WUIE_ELT_MAX];
+} __attribute__((packed));
+
+/**
+ * WUSB IE Host Information Element, Connect Availability
+ *
+ * WUSB1.0[7.5.2], bmAttributes description
+ */
+enum {
+	WUIE_HI_CAP_RECONNECT = 0,
+	WUIE_HI_CAP_LIMITED,
+	WUIE_HI_CAP_RESERVED,
+	WUIE_HI_CAP_ALL,
+};
+
+/**
+ * WUSB IE: Channel Stop (WUSB1.0[7.5.8])
+ *
+ * Tells devices the host is going to stop sending MMCs and will dissapear.
+ */
+struct wuie_channel_stop {
+	struct wuie_hdr hdr;
+	u8 attributes;
+	u8 timestamp[3];
+} __attribute__((packed));
+
+/**
+ * WUSB IE: Keepalive (WUSB1.0[7.5.9])
+ *
+ * Ask device(s) to send keepalives.
+ */
+struct wuie_keep_alive {
+	struct wuie_hdr hdr;
+	u8 bDeviceAddress[WUIE_ELT_MAX];
+} __attribute__((packed));
+
+/**
+ * WUSB IE: Reset device (WUSB1.0[7.5.11])
+ *
+ * Tell device to reset; in all truth, we can fit 4 CDIDs, but we only
+ * use it for one at the time...
+ *
+ * In any case, this request is a wee bit silly: why don't they target
+ * by address??
+ */
+struct wuie_reset {
+	struct wuie_hdr hdr;
+	struct wusb_ckhdid CDID;
+} __attribute__((packed));
+
+/**
+ * WUSB IE: Disconnect device (WUSB1.0[7.5.11])
+ *
+ * Tell device to disconnect; we can fit 4 addresses, but we only use
+ * it for one at the time...
+ */
+struct wuie_disconnect {
+	struct wuie_hdr hdr;
+	u8 bDeviceAddress;
+	u8 padding;
+} __attribute__((packed));
+
+/**
+ * WUSB IE: Host disconnect ([WUSB] section 7.5.5)
+ *
+ * Tells all connected devices to disconnect.
+ */
+struct wuie_host_disconnect {
+	struct wuie_hdr hdr;
+} __attribute__((packed));
+
+/**
+ * WUSB Device Notification header (WUSB1.0[7.6])
+ */
+struct wusb_dn_hdr {
+	u8 bType;
+	u8 notifdata[];
+} __attribute__((packed));
+
+/** Device Notification codes (WUSB1.0[Table 7-54]) */
+enum WUSB_DN {
+	WUSB_DN_CONNECT = 0x01,
+	WUSB_DN_DISCONNECT = 0x02,
+	WUSB_DN_EPRDY = 0x03,
+	WUSB_DN_MASAVAILCHANGED = 0x04,
+	WUSB_DN_RWAKE = 0x05,
+	WUSB_DN_SLEEP = 0x06,
+	WUSB_DN_ALIVE = 0x07,
+};
+
+/** WUSB Device Notification Connect */
+struct wusb_dn_connect {
+	struct wusb_dn_hdr hdr;
+	__le16 attributes;
+	struct wusb_ckhdid CDID;
+} __attribute__((packed));
+
+static inline int wusb_dn_connect_prev_dev_addr(const struct wusb_dn_connect *dn)
+{
+	return le16_to_cpu(dn->attributes) & 0xff;
+}
+
+static inline int wusb_dn_connect_new_connection(const struct wusb_dn_connect *dn)
+{
+	return (le16_to_cpu(dn->attributes) >> 8) & 0x1;
+}
+
+static inline int wusb_dn_connect_beacon_behavior(const struct wusb_dn_connect *dn)
+{
+	return (le16_to_cpu(dn->attributes) >> 9) & 0x03;
+}
+
+/** Device is alive (aka: pong) (WUSB1.0[7.6.7]) */
+struct wusb_dn_alive {
+	struct wusb_dn_hdr hdr;
+} __attribute__((packed));
+
+/** Device is disconnecting (WUSB1.0[7.6.2]) */
+struct wusb_dn_disconnect {
+	struct wusb_dn_hdr hdr;
+} __attribute__((packed));
+
+/* General constants */
+enum {
+	WUSB_TRUST_TIMEOUT_MS = 4000,	/* [WUSB] section 4.15.1 */
+};
+
+static inline size_t ckhdid_printf(char *pr_ckhdid, size_t size,
+				   const struct wusb_ckhdid *ckhdid)
+{
+	return scnprintf(pr_ckhdid, size,
+			 "%02hx %02hx %02hx %02hx %02hx %02hx %02hx %02hx "
+			 "%02hx %02hx %02hx %02hx %02hx %02hx %02hx %02hx",
+			 ckhdid->data[0],  ckhdid->data[1],
+			 ckhdid->data[2],  ckhdid->data[3],
+			 ckhdid->data[4],  ckhdid->data[5],
+			 ckhdid->data[6],  ckhdid->data[7],
+			 ckhdid->data[8],  ckhdid->data[9],
+			 ckhdid->data[10], ckhdid->data[11],
+			 ckhdid->data[12], ckhdid->data[13],
+			 ckhdid->data[14], ckhdid->data[15]);
+}
+
+/*
+ * WUSB Crypto stuff (WUSB1.0[6])
+ */
+
+extern const char *wusb_et_name(u8);
+
+/**
+ * WUSB key index WUSB1.0[7.3.2.4], for usage when setting keys for
+ * the host or the device.
+ */
+static inline u8 wusb_key_index(int index, int type, int originator)
+{
+	return (originator << 6) | (type << 4) | index;
+}
+
+#define WUSB_KEY_INDEX_TYPE_PTK			0 /* for HWA only */
+#define WUSB_KEY_INDEX_TYPE_ASSOC		1
+#define WUSB_KEY_INDEX_TYPE_GTK			2
+#define WUSB_KEY_INDEX_ORIGINATOR_HOST		0
+#define WUSB_KEY_INDEX_ORIGINATOR_DEVICE	1
+
+/* A CCM Nonce, defined in WUSB1.0[6.4.1] */
+struct aes_ccm_nonce {
+	u8 sfn[6];              /* Little Endian */
+	u8 tkid[3];             /* LE */
+	struct uwb_dev_addr dest_addr;
+	struct uwb_dev_addr src_addr;
+} __attribute__((packed));
+
+/* A CCM operation label, defined on WUSB1.0[6.5.x] */
+struct aes_ccm_label {
+	u8 data[14];
+} __attribute__((packed));
+
+/*
+ * Input to the key derivation sequence defined in
+ * WUSB1.0[6.5.1]. Rest of the data is in the CCM Nonce passed to the
+ * PRF function.
+ */
+struct wusb_keydvt_in {
+	u8 hnonce[16];
+	u8 dnonce[16];
+} __attribute__((packed));
+
+/*
+ * Output from the key derivation sequence defined in
+ * WUSB1.0[6.5.1].
+ */
+struct wusb_keydvt_out {
+	u8 kck[16];
+	u8 ptk[16];
+} __attribute__((packed));
+
+/* Pseudo Random Function WUSB1.0[6.5] */
+extern int wusb_crypto_init(void);
+extern void wusb_crypto_exit(void);
+extern ssize_t wusb_prf(void *out, size_t out_size,
+			const u8 key[16], const struct aes_ccm_nonce *_n,
+			const struct aes_ccm_label *a,
+			const void *b, size_t blen, size_t len);
+
+static inline int wusb_prf_64(void *out, size_t out_size, const u8 key[16],
+			      const struct aes_ccm_nonce *n,
+			      const struct aes_ccm_label *a,
+			      const void *b, size_t blen)
+{
+	return wusb_prf(out, out_size, key, n, a, b, blen, 64);
+}
+
+static inline int wusb_prf_128(void *out, size_t out_size, const u8 key[16],
+			       const struct aes_ccm_nonce *n,
+			       const struct aes_ccm_label *a,
+			       const void *b, size_t blen)
+{
+	return wusb_prf(out, out_size, key, n, a, b, blen, 128);
+}
+
+static inline int wusb_prf_256(void *out, size_t out_size, const u8 key[16],
+			       const struct aes_ccm_nonce *n,
+			       const struct aes_ccm_label *a,
+			       const void *b, size_t blen)
+{
+	return wusb_prf(out, out_size, key, n, a, b, blen, 256);
+}
+
+/* Key derivation WUSB1.0[6.5.1] */
+static inline int wusb_key_derive(struct wusb_keydvt_out *keydvt_out,
+				  const u8 key[16],
+				  const struct aes_ccm_nonce *n,
+				  const struct wusb_keydvt_in *keydvt_in)
+{
+	const struct aes_ccm_label a = { .data = "Pair-wise keys" };
+	return wusb_prf_256(keydvt_out, sizeof(*keydvt_out), key, n, &a,
+			    keydvt_in, sizeof(*keydvt_in));
+}
+
+/*
+ * Out-of-band MIC Generation WUSB1.0[6.5.2]
+ *
+ * Compute the MIC over @key, @n and @hs and place it in @mic_out.
+ *
+ * @mic_out:  Where to place the 8 byte MIC tag
+ * @key:      KCK from the derivation process
+ * @n:        CCM nonce, n->sfn == 0, TKID as established in the
+ *            process.
+ * @hs:       Handshake struct for phase 2 of the 4-way.
+ *            hs->bStatus and hs->bReserved are zero.
+ *            hs->bMessageNumber is 2 (WUSB1.0[7.3.2.5.2]
+ *            hs->dest_addr is the device's USB address padded with 0
+ *            hs->src_addr is the hosts's UWB device address
+ *            hs->mic is ignored (as we compute that value).
+ */
+static inline int wusb_oob_mic(u8 mic_out[8], const u8 key[16],
+			       const struct aes_ccm_nonce *n,
+			       const struct usb_handshake *hs)
+{
+	const struct aes_ccm_label a = { .data = "out-of-bandMIC" };
+	return wusb_prf_64(mic_out, 8, key, n, &a,
+			   hs, sizeof(*hs) - sizeof(hs->MIC));
+}
+
+#endif /* #ifndef __WUSB_H__ */