rt2x00: rt2800usb: rework txstatus code

Currently we read tx status register after each urb data transfer. As
callback procedure also trigger reading, that causing we have many
"threads" of reading status. To prevent that introduce TX_STATUS_READING
flags, and check if we are already in process of sequential reading
TX_STA_FIFO, before requesting new reads.

Change timer to hrtimer, that make TX_STA_FIFO overruns less possible.
Use 200 us for initial timeout, and then reschedule in 100 us period,
this values probably have to be tuned.

Make changes on txdone work. Schedule it from
rt2800usb_tx_sta_fifo_read_completed() callback when first valid status
show up. Check in callback if tx status timeout happens, and schedule
work on that condition too. That make possible to remove tx status
timeout from generic watchdog. I moved that to rt2800usb.

Loop in txdone work, that should prevent situation when we queue work,
which is already processed, and after finish work is not rescheduled
again.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 8 insertions, 2 deletions

diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index 65275efcf279..471f87cab4ab 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -38,7 +38,7 @@
 #include <linux/etherdevice.h>
 #include <linux/input-polldev.h>
 #include <linux/kfifo.h>
-#include <linux/timer.h>
+#include <linux/hrtimer.h>
 
 #include <net/mac80211.h>
 
@@ -692,6 +692,12 @@ enum rt2x00_state_flags {
 	 */
 	CONFIG_CHANNEL_HT40,
 	CONFIG_POWERSAVING,
+
+	/*
+	 * Mark we currently are sequentially reading TX_STA_FIFO register
+	 * FIXME: this is for only rt2800usb, should go to private data
+	 */
+	TX_STATUS_READING,
 };
 
 /*
@@ -974,7 +980,7 @@ struct rt2x00_dev {
 	/*
 	 * Timer to ensure tx status reports are read (rt2800usb).
 	 */
-	struct timer_list txstatus_timer;
+	struct hrtimer txstatus_timer;
 
 	/*
 	 * Tasklet for processing tx status reports (rt2800pci).