diff --git a/drivers/net/wireless/mwl8k.c b/drivers/net/wireless/mwl8k.c
index 7bbdca418314f53f847299d669098eee91e73435..93b92680d070d5a61c412f8460420000e14d02d8 100644
--- a/drivers/net/wireless/mwl8k.c
+++ b/drivers/net/wireless/mwl8k.c
@@ -139,13 +139,18 @@ struct mwl8k_priv {
struct pci_dev *pdev;
u8 name[16];
- /* firmware access lock */
- spinlock_t fw_lock;
/* firmware files and meta data */
struct mwl8k_firmware fw;
u32 part_num;
+ /* firmware access */
+ struct mutex fw_mutex;
+ struct task_struct *fw_mutex_owner;
+ int fw_mutex_depth;
+ struct completion *tx_wait;
+ struct completion *hostcmd_wait;
+
/* lock held over TX and TX reap */
spinlock_t tx_lock;
@@ -179,9 +184,6 @@ struct mwl8k_priv {
bool radio_short_preamble;
bool wmm_enabled;
- /* Set if PHY config is in progress */
- bool inconfig;
-
/* XXX need to convert this to handle multiple interfaces */
bool capture_beacon;
u8 capture_bssid[ETH_ALEN];
@@ -200,8 +202,6 @@ struct mwl8k_priv {
/* Work thread to serialize configuration requests */
struct workqueue_struct *config_wq;
- struct completion *hostcmd_wait;
- struct completion *tx_wait;
};
/* Per interface specific private data */
@@ -1113,6 +1113,9 @@ static int mwl8k_scan_tx_ring(struct mwl8k_priv *priv,
return ndescs;
}
+/*
+ * Must be called with hw->fw_mutex held and tx queues stopped.
+ */
static int mwl8k_tx_wait_empty(struct ieee80211_hw *hw)
{
struct mwl8k_priv *priv = hw->priv;
@@ -1122,9 +1125,6 @@ static int mwl8k_tx_wait_empty(struct ieee80211_hw *hw)
might_sleep();
- if (priv->tx_wait != NULL)
- printk(KERN_ERR "WARNING Previous TXWaitEmpty instance\n");
-
spin_lock_bh(&priv->tx_lock);
count = mwl8k_txq_busy(priv);
if (count) {
@@ -1140,7 +1140,7 @@ static int mwl8k_tx_wait_empty(struct ieee80211_hw *hw)
int newcount;
timeout = wait_for_completion_timeout(&cmd_wait,
- msecs_to_jiffies(1000));
+ msecs_to_jiffies(5000));
if (timeout)
return 0;
@@ -1149,7 +1149,7 @@ static int mwl8k_tx_wait_empty(struct ieee80211_hw *hw)
newcount = mwl8k_txq_busy(priv);
spin_unlock_bh(&priv->tx_lock);
- printk(KERN_ERR "%s(%u) TIMEDOUT:1000ms Pend:%u-->%u\n",
+ printk(KERN_ERR "%s(%u) TIMEDOUT:5000ms Pend:%u-->%u\n",
__func__, __LINE__, count, newcount);
mwl8k_scan_tx_ring(priv, txinfo);
@@ -1228,10 +1228,10 @@ static void mwl8k_txq_reclaim(struct ieee80211_hw *hw, int index, int force)
ieee80211_tx_status_irqsafe(hw, skb);
- wake = !priv->inconfig && priv->radio_on;
+ wake = 1;
}
- if (wake)
+ if (wake && priv->radio_on && !mutex_is_locked(&priv->fw_mutex))
ieee80211_wake_queue(hw, index);
}
@@ -1359,6 +1359,60 @@ mwl8k_txq_xmit(struct ieee80211_hw *hw, int index, struct sk_buff *skb)
}
+/*
+ * Firmware access.
+ *
+ * We have the following requirements for issuing firmware commands:
+ * - Some commands require that the packet transmit path is idle when
+ * the command is issued. (For simplicity, we'll just quiesce the
+ * transmit path for every command.)
+ * - There are certain sequences of commands that need to be issued to
+ * the hardware sequentially, with no other intervening commands.
+ *
+ * This leads to an implementation of a "firmware lock" as a mutex that
+ * can be taken recursively, and which is taken by both the low-level
+ * command submission function (mwl8k_post_cmd) as well as any users of
+ * that function that require issuing of an atomic sequence of commands,
+ * and quiesces the transmit path whenever it's taken.
+ */
+static int mwl8k_fw_lock(struct ieee80211_hw *hw)
+{
+ struct mwl8k_priv *priv = hw->priv;
+
+ if (priv->fw_mutex_owner != current) {
+ int rc;
+
+ mutex_lock(&priv->fw_mutex);
+ ieee80211_stop_queues(hw);
+
+ rc = mwl8k_tx_wait_empty(hw);
+ if (rc) {
+ ieee80211_wake_queues(hw);
+ mutex_unlock(&priv->fw_mutex);
+
+ return rc;
+ }
+
+ priv->fw_mutex_owner = current;
+ }
+
+ priv->fw_mutex_depth++;
+
+ return 0;
+}
+
+static void mwl8k_fw_unlock(struct ieee80211_hw *hw)
+{
+ struct mwl8k_priv *priv = hw->priv;
+
+ if (!--priv->fw_mutex_depth) {
+ ieee80211_wake_queues(hw);
+ priv->fw_mutex_owner = NULL;
+ mutex_unlock(&priv->fw_mutex);
+ }
+}
+
+
/*
* Command processing.
*/
@@ -1384,28 +1438,28 @@ static int mwl8k_post_cmd(struct ieee80211_hw *hw, struct mwl8k_cmd_pkt *cmd)
if (pci_dma_mapping_error(priv->pdev, dma_addr))
return -ENOMEM;
- if (priv->hostcmd_wait != NULL)
- printk(KERN_ERR "WARNING host command in progress\n");
+ rc = mwl8k_fw_lock(hw);
+ if (rc)
+ return rc;
- spin_lock_irq(&priv->fw_lock);
priv->hostcmd_wait = &cmd_wait;
iowrite32(dma_addr, regs + MWL8K_HIU_GEN_PTR);
iowrite32(MWL8K_H2A_INT_DOORBELL,
regs + MWL8K_HIU_H2A_INTERRUPT_EVENTS);
iowrite32(MWL8K_H2A_INT_DUMMY,
regs + MWL8K_HIU_H2A_INTERRUPT_EVENTS);
- spin_unlock_irq(&priv->fw_lock);
timeout = wait_for_completion_timeout(&cmd_wait,
msecs_to_jiffies(MWL8K_CMD_TIMEOUT_MS));
+ priv->hostcmd_wait = NULL;
+
+ mwl8k_fw_unlock(hw);
+
pci_unmap_single(priv->pdev, dma_addr, dma_size,
PCI_DMA_BIDIRECTIONAL);
if (!timeout) {
- spin_lock_irq(&priv->fw_lock);
- priv->hostcmd_wait = NULL;
- spin_unlock_irq(&priv->fw_lock);
printk(KERN_ERR "%s: Command %s timeout after %u ms\n",
priv->name,
mwl8k_cmd_name(cmd->code, buf, sizeof(buf)),
@@ -2336,17 +2390,14 @@ static irqreturn_t mwl8k_interrupt(int irq, void *dev_id)
}
if (status & MWL8K_A2H_INT_OPC_DONE) {
- if (priv->hostcmd_wait != NULL) {
+ if (priv->hostcmd_wait != NULL)
complete(priv->hostcmd_wait);
- priv->hostcmd_wait = NULL;
- }
}
if (status & MWL8K_A2H_INT_QUEUE_EMPTY) {
- if (!priv->inconfig &&
- priv->radio_on &&
- mwl8k_txq_busy(priv))
- mwl8k_tx_start(priv);
+ if (!mutex_is_locked(&priv->fw_mutex) &&
+ priv->radio_on && mwl8k_txq_busy(priv))
+ mwl8k_tx_start(priv);
}
return IRQ_HANDLED;
@@ -2395,41 +2446,13 @@ static void mwl8k_config_thread(struct work_struct *wt)
{
struct mwl8k_work_struct *worker = (struct mwl8k_work_struct *)wt;
struct ieee80211_hw *hw = worker->hw;
- struct mwl8k_priv *priv = hw->priv;
int rc = 0;
- int iter;
- spin_lock_irq(&priv->tx_lock);
- priv->inconfig = true;
- spin_unlock_irq(&priv->tx_lock);
-
- ieee80211_stop_queues(hw);
-
- /*
- * Wait for host queues to drain before doing PHY
- * reconfiguration. This avoids interrupting any in-flight
- * DMA transfers to the hardware.
- */
- iter = 4;
- do {
- rc = mwl8k_tx_wait_empty(hw);
- if (rc)
- printk(KERN_ERR "%s() txwait timeout=1000ms "
- "Retry:%u/%u\n", __func__, 4 - iter + 1, 4);
- } while (rc && --iter);
-
- rc = iter ? 0 : -ETIMEDOUT;
-
- if (!rc)
+ rc = mwl8k_fw_lock(hw);
+ if (!rc) {
rc = worker->wfunc(wt);
-
- spin_lock_irq(&priv->tx_lock);
- priv->inconfig = false;
- if (priv->pending_tx_pkts && priv->radio_on)
- mwl8k_tx_start(priv);
- spin_unlock_irq(&priv->tx_lock);
-
- ieee80211_wake_queues(hw);
+ mwl8k_fw_unlock(hw);
+ }
worker->rc = rc;
complete(worker->cmd_wait);
@@ -3145,15 +3168,10 @@ static int __devinit mwl8k_probe(struct pci_dev *pdev,
priv = hw->priv;
priv->hw = hw;
priv->pdev = pdev;
- priv->hostcmd_wait = NULL;
- priv->tx_wait = NULL;
- priv->inconfig = false;
priv->wmm_enabled = false;
priv->pending_tx_pkts = 0;
strncpy(priv->name, MWL8K_NAME, sizeof(priv->name));
- spin_lock_init(&priv->fw_lock);
-
SET_IEEE80211_DEV(hw, &pdev->dev);
pci_set_drvdata(pdev, hw);
@@ -3219,6 +3237,12 @@ static int __devinit mwl8k_probe(struct pci_dev *pdev,
goto err_iounmap;
rxq_refill(hw, 0, INT_MAX);
+ mutex_init(&priv->fw_mutex);
+ priv->fw_mutex_owner = NULL;
+ priv->fw_mutex_depth = 0;
+ priv->tx_wait = NULL;
+ priv->hostcmd_wait = NULL;
+
spin_lock_init(&priv->tx_lock);
for (i = 0; i < MWL8K_TX_QUEUES; i++) {