libertas: convert libertas driver to use an event/cmdresp queue

This patch (co-developed by Dan Williams and Holger Schurig) uses a kfifo
object for events and a swapping buffer scheme for the command response to
preserve the zero-copy semantics of the CF driver and keep memory usage low.
The main thread should only ever touch the buffer indexed by priv->resp_idx,
while the interface code is free to write to the second buffer, then swap
priv->resp_idx under the driver spinlock.  The firmware specs only permit
one in-flight command, so there will only ever be one command response to
process at a time.

Signed-off-by: Holger Schurig <hs4233@mail.mn-solutions.de>
Signed-off-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 10 insertions, 17 deletions

diff --git a/drivers/net/wireless/libertas/dev.h b/drivers/net/wireless/libertas/dev.h
index 1e6bae80396b..0d9edb9b11f5 100644
--- a/drivers/net/wireless/libertas/dev.h
+++ b/drivers/net/wireless/libertas/dev.h
@@ -129,10 +129,6 @@ struct lbs_private {
 	u32 bbp_offset;
 	u32 rf_offset;
 
-	/** Upload length */
-	u32 upld_len;
-	/* Upload buffer */
-	u8 upld_buf[LBS_UPLD_SIZE];
 	/* Download sent:
 	   bit0 1/0=data_sent/data_tx_done,
 	   bit1 1/0=cmd_sent/cmd_tx_done,
@@ -155,21 +151,16 @@ struct lbs_private {
 
 	/** Hardware access */
 	int (*hw_host_to_card) (struct lbs_private *priv, u8 type, u8 *payload, u16 nb);
-	int (*hw_get_int_status) (struct lbs_private *priv, u8 *);
-	int (*hw_read_event_cause) (struct lbs_private *);
 
 	/* Wake On LAN */
 	uint32_t wol_criteria;
 	uint8_t wol_gpio;
 	uint8_t wol_gap;
 
-	/* was struct lbs_adapter from here... */
-
 	/** Wlan adapter data structure*/
 	/** STATUS variables */
 	u32 fwrelease;
 	u32 fwcapinfo;
-	/* protected with big lock */
 
 	struct mutex lock;
 
@@ -181,7 +172,6 @@ struct lbs_private {
 
 	/** command-related variables */
 	u16 seqnum;
-	/* protected by big lock */
 
 	struct cmd_ctrl_node *cmd_array;
 	/** Current command */
@@ -194,12 +184,17 @@ struct lbs_private {
 	struct list_head cmdpendingq;
 
 	wait_queue_head_t cmd_pending;
-	/* command related variables protected by priv->driver_lock */
 
-	/** Async and Sync Event variables */
-	u32 intcounter;
-	u32 eventcause;
-	u8 nodename[16];	/* nickname */
+	/* Command responses sent from the hardware to the driver */
+	u8 resp_idx;
+	u8 resp_buf[2][LBS_UPLD_SIZE];
+	u32 resp_len[2];
+
+	/* Events sent from hardware to driver */
+	struct kfifo *event_fifo;
+
+	/* nickname */
+	u8 nodename[16];
 
 	/** spin locks */
 	spinlock_t driver_lock;
@@ -209,8 +204,6 @@ struct lbs_private {
 	int nr_retries;
 	int cmd_timed_out;
 
-	u8 hisregcpy;
-
 	/** current ssid/bssid related parameters*/
 	struct current_bss_params curbssparams;