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/*
* Intel 1480 Wireless UWB Link USB
* Header formats, constants, general internal interfaces
*
*
* 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 is not an standard interface.
*
* FIXME: docs
*
* i1480u-wlp is pretty simple: two endpoints, one for tx, one for
* rx. rx is polled. Network packets (ethernet, whatever) are wrapped
* in i1480 TX or RX headers (for sending over the air), and these
* packets are wrapped in UNTD headers (for sending to the WLP UWB
* controller).
*
* UNTD packets (UNTD hdr + i1480 hdr + network packet) packets
* cannot be bigger than i1480u_MAX_FRG_SIZE. When this happens, the
* i1480 packet is broken in chunks/packets:
*
* UNTD-1st.hdr + i1480.hdr + payload
* UNTD-next.hdr + payload
* ...
* UNTD-last.hdr + payload
*
* so that each packet is smaller or equal than i1480u_MAX_FRG_SIZE.
*
* All HW structures and bitmaps are little endian, so we need to play
* ugly tricks when defining bitfields. Hoping for the day GCC
* implements __attribute__((endian(1234))).
*
* FIXME: ROADMAP to the whole implementation
*/
#ifndef __i1480u_wlp_h__
#define __i1480u_wlp_h__
#include <linux/usb.h>
#include <linux/netdevice.h>
#include <linux/uwb.h> /* struct uwb_rc, struct uwb_notifs_handler */
#include <linux/wlp.h>
#include "../i1480-wlp.h"
#undef i1480u_FLOW_CONTROL /* Enable flow control code */
/**
* Basic flow control
*/
enum {
i1480u_TX_INFLIGHT_MAX = 1000,
i1480u_TX_INFLIGHT_THRESHOLD = 100,
};
/** Maximum size of a transaction that we can tx/rx */
enum {
/* Maximum packet size computed as follows: max UNTD header (8) +
* i1480 RX header (8) + max Ethernet header and payload (4096) +
* Padding added by skb_reserve (2) to make post Ethernet payload
* start on 16 byte boundary*/
i1480u_MAX_RX_PKT_SIZE = 4114,
i1480u_MAX_FRG_SIZE = 512,
i1480u_RX_BUFS = 9,
};
/**
* UNTD packet type
*
* We need to fragment any payload whose UNTD packet is going to be
* bigger than i1480u_MAX_FRG_SIZE.
*/
enum i1480u_pkt_type {
i1480u_PKT_FRAG_1ST = 0x1,
i1480u_PKT_FRAG_NXT = 0x0,
i1480u_PKT_FRAG_LST = 0x2,
i1480u_PKT_FRAG_CMP = 0x3
};
enum {
i1480u_PKT_NONE = 0x4,
};
/** USB Network Transfer Descriptor - common */
struct untd_hdr {
u8 type;
__le16 len;
} __attribute__((packed));
static inline enum i1480u_pkt_type untd_hdr_type(const struct untd_hdr *hdr)
{
return hdr->type & 0x03;
}
static inline int untd_hdr_rx_tx(const struct untd_hdr *hdr)
{
return (hdr->type >> 2) & 0x01;
}
static inline void untd_hdr_set_type(struct untd_hdr *hdr, enum i1480u_pkt_type type)
{
hdr->type = (hdr->type & ~0x03) | type;
}
static inline void untd_hdr_set_rx_tx(struct untd_hdr *hdr, int rx_tx)
{
hdr->type = (hdr->type & ~0x04) | (rx_tx << 2);
}
/**
* USB Network Transfer Descriptor - Complete Packet
*
* This is for a packet that is smaller (header + payload) than
* i1480u_MAX_FRG_SIZE.
*
* @hdr.total_len is the size of the payload; the payload doesn't
* count this header nor the padding, but includes the size of i1480
* header.
*/
struct untd_hdr_cmp {
struct untd_hdr hdr;
u8 padding;
} __attribute__((packed));
/**
* USB Network Transfer Descriptor - First fragment
*
* @hdr.len is the size of the *whole packet* (excluding UNTD
* headers); @fragment_len is the size of the payload (excluding UNTD
* headers, but including i1480 headers).
*/
struct untd_hdr_1st {
struct untd_hdr hdr;
__le16 fragment_len;
u8 padding[3];
} __attribute__((packed));
/**
* USB Network Transfer Descriptor - Next / Last [Rest]
*
* @hdr.len is the size of the payload, not including headrs.
*/
struct untd_hdr_rst {
struct untd_hdr hdr;
u8 padding;
} __attribute__((packed));
/**
* Transmission context
*
* Wraps all the stuff needed to track a pending/active tx
* operation.
*/
struct i1480u_tx {
struct list_head list_node;
struct i1480u *i1480u;
struct urb *urb;
struct sk_buff *skb;
struct wlp_tx_hdr *wlp_tx_hdr;
void *buf; /* if NULL, no new buf was used */
size_t buf_size;
};
/**
* Basic flow control
*
* We maintain a basic flow control counter. "count" how many TX URBs are
* outstanding. Only allow "max"
* TX URBs to be outstanding. If this value is reached the queue will be
* stopped. The queue will be restarted when there are
* "threshold" URBs outstanding.
* Maintain a counter of how many time the TX queue needed to be restarted
* due to the "max" being exceeded and the "threshold" reached again. The
* timestamp "restart_ts" is to keep track from when the counter was last
* queried (see sysfs handling of file wlp_tx_inflight).
*/
struct i1480u_tx_inflight {
atomic_t count;
unsigned long max;
unsigned long threshold;
unsigned long restart_ts;
atomic_t restart_count;
};
/**
* Instance of a i1480u WLP interface
*
* Keeps references to the USB device that wraps it, as well as it's
* interface and associated UWB host controller. As well, it also
* keeps a link to the netdevice for integration into the networking
* stack.
* We maintian separate error history for the tx and rx endpoints because
* the implementation does not rely on locking - having one shared
* structure between endpoints may cause problems. Adding locking to the
* implementation will have higher cost than adding a separate structure.
*/
struct i1480u {
struct usb_device *usb_dev;
struct usb_interface *usb_iface;
struct net_device *net_dev;
spinlock_t lock;
/* RX context handling */
struct sk_buff *rx_skb;
struct uwb_dev_addr rx_srcaddr;
size_t rx_untd_pkt_size;
struct i1480u_rx_buf {
struct i1480u *i1480u; /* back pointer */
struct urb *urb;
struct sk_buff *data; /* i1480u_MAX_RX_PKT_SIZE each */
} rx_buf[i1480u_RX_BUFS]; /* N bufs */
spinlock_t tx_list_lock; /* TX context */
struct list_head tx_list;
u8 tx_stream;
struct stats lqe_stats, rssi_stats; /* radio statistics */
/* Options we can set from sysfs */
struct wlp_options options;
struct uwb_notifs_handler uwb_notifs_handler;
struct edc tx_errors;
struct edc rx_errors;
struct wlp wlp;
#ifdef i1480u_FLOW_CONTROL
struct urb *notif_urb;
struct edc notif_edc; /* error density counter */
u8 notif_buffer[1];
#endif
struct i1480u_tx_inflight tx_inflight;
};
/* Internal interfaces */
extern void i1480u_rx_cb(struct urb *urb);
extern int i1480u_rx_setup(struct i1480u *);
extern void i1480u_rx_release(struct i1480u *);
extern void i1480u_tx_release(struct i1480u *);
extern int i1480u_xmit_frame(struct wlp *, struct sk_buff *,
struct uwb_dev_addr *);
extern void i1480u_stop_queue(struct wlp *);
extern void i1480u_start_queue(struct wlp *);
extern int i1480u_sysfs_setup(struct i1480u *);
extern void i1480u_sysfs_release(struct i1480u *);
/* netdev interface */
extern int i1480u_open(struct net_device *);
extern int i1480u_stop(struct net_device *);
extern netdev_tx_t i1480u_hard_start_xmit(struct sk_buff *,
struct net_device *);
extern void i1480u_tx_timeout(struct net_device *);
extern int i1480u_set_config(struct net_device *, struct ifmap *);
extern int i1480u_change_mtu(struct net_device *, int);
extern void i1480u_uwb_notifs_cb(void *, struct uwb_dev *, enum uwb_notifs);
/* bandwidth allocation callback */
extern void i1480u_bw_alloc_cb(struct uwb_rsv *);
/* Sys FS */
extern struct attribute_group i1480u_wlp_attr_group;
#endif /* #ifndef __i1480u_wlp_h__ */
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