uwb: add the i1480 WLP driver

Add the driver for the WLP capability of the Intel i1480 device.

Signed-off-by: David Vrabel <david.vrabel@csr.com>

1 files changed, 284 insertions, 0 deletions

diff --git a/drivers/uwb/i1480/i1480u-wlp/i1480u-wlp.h b/drivers/uwb/i1480/i1480u-wlp/i1480u-wlp.h
new file mode 100644
index 00000000000..5f1b2951bb8
--- /dev/null
+++ b/drivers/uwb/i1480/i1480u-wlp/i1480u-wlp.h
@@ -0,0 +1,284 @@
+/*
+ * 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;
+	struct net_device_stats stats;
+
+	/* 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 int 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 struct net_device_stats *i1480u_get_stats(struct net_device *);
+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__ */