ath5k: Add new function to stop rx/tx DMA
* Add a new function to stop rx/tx dma and use in when reset starts
Signed-off-by: Nick Kossifidis <mickflemm@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath5k/dma.c b/drivers/net/wireless/ath/ath5k/dma.c
index b991b05..ca0467e 100644
--- a/drivers/net/wireless/ath/ath5k/dma.c
+++ b/drivers/net/wireless/ath/ath5k/dma.c
@@ -126,7 +126,7 @@
/* Return if queue is declared inactive */
if (ah->ah_txq[queue].tqi_type == AR5K_TX_QUEUE_INACTIVE)
- return -EIO;
+ return -EINVAL;
if (ah->ah_version == AR5K_AR5210) {
tx_queue = ath5k_hw_reg_read(ah, AR5K_CR);
@@ -174,7 +174,7 @@
*
* Stop DMA transmit on a specific hw queue and drain queue so we don't
* have any pending frames. Returns -EBUSY if we still have pending frames,
- * -EINVAL if queue number is out of range.
+ * -EINVAL if queue number is out of range or inactive.
*
*/
int ath5k_hw_stop_tx_dma(struct ath5k_hw *ah, unsigned int queue)
@@ -186,7 +186,7 @@
/* Return if queue is declared inactive */
if (ah->ah_txq[queue].tqi_type == AR5K_TX_QUEUE_INACTIVE)
- return -EIO;
+ return -EINVAL;
if (ah->ah_version == AR5K_AR5210) {
tx_queue = ath5k_hw_reg_read(ah, AR5K_CR);
@@ -733,3 +733,49 @@
ath5k_hw_set_imr(ah, ah->ah_imr);
}
+
+/**
+ * ath5k_hw_dma_stop - stop DMA unit
+ *
+ * @ah: The &struct ath5k_hw
+ *
+ * Stop tx/rx DMA and interrupts. Returns
+ * -EBUSY if tx or rx dma failed to stop.
+ *
+ * XXX: Sometimes DMA unit hangs and we have
+ * stuck frames on tx queues, only a reset
+ * can fix that.
+ */
+int ath5k_hw_dma_stop(struct ath5k_hw *ah)
+{
+ int i, qmax, err;
+ err = 0;
+
+ /* Disable interrupts */
+ ath5k_hw_set_imr(ah, 0);
+
+ /* Stop rx dma */
+ err = ath5k_hw_stop_rx_dma(ah);
+ if (err)
+ return err;
+
+ /* Clear any pending interrupts
+ * and disable tx dma */
+ if (ah->ah_version != AR5K_AR5210) {
+ ath5k_hw_reg_write(ah, 0xffffffff, AR5K_PISR);
+ qmax = AR5K_NUM_TX_QUEUES;
+ } else {
+ /* PISR/SISR Not available on 5210 */
+ ath5k_hw_reg_read(ah, AR5K_ISR);
+ qmax = AR5K_NUM_TX_QUEUES_NOQCU;
+ }
+
+ for (i = 0; i < qmax; i++) {
+ err = ath5k_hw_stop_tx_dma(ah, i);
+ /* -EINVAL -> queue inactive */
+ if (err != -EINVAL)
+ return err;
+ }
+
+ return err;
+}