wl12xx: add driver

wl12xx is a driver for TI wl1251 802.11 chipset designed for embedded
devices, supporting both SDIO and SPI busses. Currently the driver
supports only SPI. Adding support 1253 (the 5 GHz version) should be
relatively easy. More information here:

http://focus.ti.com/general/docs/wtbu/wtbuproductcontent.tsp?contentId=4711&navigationId=12494&templateId=6123

(Collapsed original sequence of pre-merge patches into single commit for
initial merge. -- JWL)

Signed-off-by: Kalle Valo <kalle.valo@nokia.com>
Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 215 insertions, 0 deletions

diff --git a/drivers/net/wireless/wl12xx/tx.h b/drivers/net/wireless/wl12xx/tx.h
new file mode 100644
index 00000000000..dc82691f4c1
--- /dev/null
+++ b/drivers/net/wireless/wl12xx/tx.h
@@ -0,0 +1,215 @@
+/*
+ * This file is part of wl12xx
+ *
+ * Copyright (c) 1998-2007 Texas Instruments Incorporated
+ * Copyright (C) 2008 Nokia Corporation
+ *
+ * Contact: Kalle Valo <kalle.valo@nokia.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 St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#ifndef __WL12XX_TX_H__
+#define __WL12XX_TX_H__
+
+#include <linux/bitops.h>
+
+/*
+ *
+ * TX PATH
+ *
+ * The Tx path uses a double buffer and a tx_control structure, each located
+ * at a fixed address in the device's memory. On startup, the host retrieves
+ * the pointers to these addresses. A double buffer allows for continuous data
+ * flow towards the device. The host keeps track of which buffer is available
+ * and alternates between these two buffers on a per packet basis.
+ *
+ * The size of each of the two buffers is large enough to hold the longest
+ * 802.3 packet - maximum size Ethernet packet + header + descriptor.
+ * TX complete indication will be received a-synchronously in a TX done cyclic
+ * buffer which is composed of 16 tx_result descriptors structures and is used
+ * in a cyclic manner.
+ *
+ * The TX (HOST) procedure is as follows:
+ * 1. Read the Tx path status, that will give the data_out_count.
+ * 2. goto 1, if not possible.
+ *    i.e. if data_in_count - data_out_count >= HwBuffer size (2 for double
+ *    buffer).
+ * 3. Copy the packet (preceded by double_buffer_desc), if possible.
+ *    i.e. if data_in_count - data_out_count < HwBuffer size (2 for double
+ *    buffer).
+ * 4. increment data_in_count.
+ * 5. Inform the firmware by generating a firmware internal interrupt.
+ * 6. FW will increment data_out_count after it reads the buffer.
+ *
+ * The TX Complete procedure:
+ * 1. To get a TX complete indication the host enables the tx_complete flag in
+ *    the TX descriptor Structure.
+ * 2. For each packet with a Tx Complete field set, the firmware adds the
+ *    transmit results to the cyclic buffer (txDoneRing) and sets both done_1
+ *    and done_2 to 1 to indicate driver ownership.
+ * 3. The firmware sends a Tx Complete interrupt to the host to trigger the
+ *    host to process the new data. Note: interrupt will be send per packet if
+ *    TX complete indication was requested in tx_control or per crossing
+ *    aggregation threshold.
+ * 4. After receiving the Tx Complete interrupt, the host reads the
+ *    TxDescriptorDone information in a cyclic manner and clears both done_1
+ *    and done_2 fields.
+ *
+ */
+
+#define TX_COMPLETE_REQUIRED_BIT	0x80
+#define TX_STATUS_DATA_OUT_COUNT_MASK   0xf
+#define WL12XX_TX_ALIGN_TO 4
+#define WL12XX_TX_ALIGN(len) (((len) + WL12XX_TX_ALIGN_TO - 1) & \
+			     ~(WL12XX_TX_ALIGN_TO - 1))
+#define WL12XX_TKIP_IV_SPACE 4
+
+struct tx_control {
+	/* Rate Policy (class) index */
+	unsigned rate_policy:3;
+
+	/* When set, no ack policy is expected */
+	unsigned ack_policy:1;
+
+	/*
+	 * Packet type:
+	 * 0 -> 802.11
+	 * 1 -> 802.3
+	 * 2 -> IP
+	 * 3 -> raw codec
+	 */
+	unsigned packet_type:2;
+
+	/* If set, this is a QoS-Null or QoS-Data frame */
+	unsigned qos:1;
+
+	/*
+	 * If set, the target triggers the tx complete INT
+	 * upon frame sending completion.
+	 */
+	unsigned tx_complete:1;
+
+	/* 2 bytes padding before packet header */
+	unsigned xfer_pad:1;
+
+	unsigned reserved:7;
+} __attribute__ ((packed));
+
+
+struct tx_double_buffer_desc {
+	/* Length of payload, including headers. */
+	u16 length;
+
+	/*
+	 * A bit mask that specifies the initial rate to be used
+	 * Possible values are:
+	 * 0x0001 - 1Mbits
+	 * 0x0002 - 2Mbits
+	 * 0x0004 - 5.5Mbits
+	 * 0x0008 - 6Mbits
+	 * 0x0010 - 9Mbits
+	 * 0x0020 - 11Mbits
+	 * 0x0040 - 12Mbits
+	 * 0x0080 - 18Mbits
+	 * 0x0100 - 22Mbits
+	 * 0x0200 - 24Mbits
+	 * 0x0400 - 36Mbits
+	 * 0x0800 - 48Mbits
+	 * 0x1000 - 54Mbits
+	 */
+	u16 rate;
+
+	/* Time in us that a packet can spend in the target */
+	u32 expiry_time;
+
+	/* index of the TX queue used for this packet */
+	u8 xmit_queue;
+
+	/* Used to identify a packet */
+	u8 id;
+
+	struct tx_control control;
+
+	/*
+	 * The FW should cut the packet into fragments
+	 * of this size.
+	 */
+	u16 frag_threshold;
+
+	/* Numbers of HW queue blocks to be allocated */
+	u8 num_mem_blocks;
+
+	u8 reserved;
+} __attribute__ ((packed));
+
+enum {
+	TX_SUCCESS              = 0,
+	TX_DMA_ERROR            = BIT(7),
+	TX_DISABLED             = BIT(6),
+	TX_RETRY_EXCEEDED       = BIT(5),
+	TX_TIMEOUT              = BIT(4),
+	TX_KEY_NOT_FOUND        = BIT(3),
+	TX_ENCRYPT_FAIL         = BIT(2),
+	TX_UNAVAILABLE_PRIORITY = BIT(1),
+};
+
+struct tx_result {
+	/*
+	 * Ownership synchronization between the host and
+	 * the firmware. If done_1 and done_2 are cleared,
+	 * owned by the FW (no info ready).
+	 */
+	u8 done_1;
+
+	/* same as double_buffer_desc->id */
+	u8 id;
+
+	/*
+	 * Total air access duration consumed by this
+	 * packet, including all retries and overheads.
+	 */
+	u16 medium_usage;
+
+	/* Total media delay (from 1st EDCA AIFS counter until TX Complete). */
+	u32 medium_delay;
+
+	/* Time between host xfer and tx complete */
+	u32 fw_hnadling_time;
+
+	/* The LS-byte of the last TKIP sequence number. */
+	u8 lsb_seq_num;
+
+	/* Retry count */
+	u8 ack_failures;
+
+	/* At which rate we got a ACK */
+	u16 rate;
+
+	u16 reserved;
+
+	/* TX_* */
+	u8 status;
+
+	/* See done_1 */
+	u8 done_2;
+} __attribute__ ((packed));
+
+void wl12xx_tx_work(struct work_struct *work);
+void wl12xx_tx_complete(struct wl12xx *wl);
+void wl12xx_tx_flush(struct wl12xx *wl);
+
+#endif