diff options
Diffstat (limited to 'drivers/staging/cw1200/wsm.c')
| -rw-r--r-- | drivers/staging/cw1200/wsm.c | 67 |
1 files changed, 49 insertions, 18 deletions
diff --git a/drivers/staging/cw1200/wsm.c b/drivers/staging/cw1200/wsm.c index 21df2bf0bfe..d1ea95c28e4 100644 --- a/drivers/staging/cw1200/wsm.c +++ b/drivers/staging/cw1200/wsm.c @@ -33,7 +33,7 @@ #define WSM_CMD_JOIN_TIMEOUT (7 * HZ) /* Join timeout is 5 sec. in FW */ #define WSM_CMD_START_TIMEOUT (7 * HZ) #define WSM_CMD_RESET_TIMEOUT (3 * HZ) /* 2 sec. timeout was observed. */ -#define WSM_CMD_LAST_CHANCE_TIMEOUT (10 * HZ) +#define WSM_CMD_LAST_CHANCE_TIMEOUT (HZ * 3 / 2) #define WSM_SKIP(buf, size) \ do { \ @@ -1082,6 +1082,10 @@ int wsm_cmd_send(struct cw1200_common *priv, priv->wsm_cmd_wq, priv->wsm_cmd.done, WSM_CMD_LAST_CHANCE_TIMEOUT) <= 0); } + + /* Kill BH thread to report the error to the top layer. */ + priv->bh_error = 1; + wake_up(&priv->bh_wq); ret = -ETIMEDOUT; } else { spin_lock(&priv->wsm_cmd.lock); @@ -1100,15 +1104,8 @@ void wsm_lock_tx(struct cw1200_common *priv) { wsm_cmd_lock(priv); if (atomic_add_return(1, &priv->tx_lock) == 1) { - if (priv->bh_error) { - wsm_printk(KERN_ERR "fatal error occured, " - "could not take lock\n"); - } else { - WARN_ON(wait_event_timeout(priv->bh_evt_wq, - !priv->hw_bufs_used, - WSM_CMD_LAST_CHANCE_TIMEOUT) <= 0); + if (wsm_flush_tx(priv)) wsm_printk(KERN_DEBUG "[WSM] TX is locked.\n"); - } } wsm_cmd_unlock(priv); } @@ -1116,18 +1113,52 @@ void wsm_lock_tx(struct cw1200_common *priv) void wsm_lock_tx_async(struct cw1200_common *priv) { if (atomic_add_return(1, &priv->tx_lock) == 1) - wsm_printk(KERN_DEBUG "[WSM] TX is locked.\n"); + wsm_printk(KERN_DEBUG "[WSM] TX is locked (async).\n"); } -void wsm_flush_tx(struct cw1200_common *priv) +bool wsm_flush_tx(struct cw1200_common *priv) { - if (priv->bh_error) - wsm_printk(KERN_ERR "fatal error occured, will not flush\n"); - else { - BUG_ON(!atomic_read(&priv->tx_lock)); - WARN_ON(wait_event_timeout(priv->bh_evt_wq, - !priv->hw_bufs_used, - WSM_CMD_LAST_CHANCE_TIMEOUT) <= 0); + unsigned long timestamp = jiffies; + bool pending = false; + long timeout; + int i; + + /* Flush must be called with TX lock held. */ + BUG_ON(!atomic_read(&priv->tx_lock)); + + /* First check if we really need to do something. + * It is safe to use unprotected access, as hw_bufs_used + * can only decrements. */ + if (!priv->hw_bufs_used) + return true; + + if (priv->bh_error) { + /* In case of failure do not wait for magic. */ + wsm_printk(KERN_ERR "[WSM] Fatal error occured, " + "will not flush TX.\n"); + return false; + } else { + /* Get a timestamp of "oldest" frame */ + for (i = 0; i < 4; ++i) + pending |= cw1200_queue_get_xmit_timestamp( + &priv->tx_queue[i], + ×tamp); + /* It is allowed to lock TX with only a command in the pipe. */ + if (!pending) + return true; + + timeout = timestamp + WSM_CMD_LAST_CHANCE_TIMEOUT - jiffies; + if (timeout < 0 || wait_event_timeout(priv->bh_evt_wq, + !priv->hw_bufs_used, + timeout) <= 0) { + /* Hmmm... Not good. Frame had stuck in firmware. */ + priv->bh_error = 1; + wake_up(&priv->bh_wq); + return false; + } + + /* Ok, everything is flushed. */ + return true; } } |