net: ethernet: ti: davinci_cpdma: allow desc split while down

That's possible to set ring params while interfaces are down. When
interface gets up it uses number of descs to fill rx queue and on
later on changes to create rx pools. Usually, this resplit can happen
after phy is up, but it can be needed before this, so allow it to
happen while setting number of rx descs, when interfaces are down.
Also, if no dependency on intf state, move it to cpdma layer, where
it should be.

Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 11 insertions, 6 deletions

diff --git a/drivers/net/ethernet/ti/cpsw_ethtool.c b/drivers/net/ethernet/ti/cpsw_ethtool.c
index f60dc1dfc443..c477e6b620d6 100644
--- a/drivers/net/ethernet/ti/cpsw_ethtool.c
+++ b/drivers/net/ethernet/ti/cpsw_ethtool.c
@@ -650,7 +650,7 @@ int cpsw_set_ringparam(struct net_device *ndev,
 {
 	struct cpsw_priv *priv = netdev_priv(ndev);
 	struct cpsw_common *cpsw = priv->cpsw;
-	int ret;
+	int descs_num, ret;
 
 	/* ignore ering->tx_pending - only rx_pending adjustment is supported */
 
@@ -659,20 +659,25 @@ int cpsw_set_ringparam(struct net_device *ndev,
 	    ering->rx_pending > (cpsw->descs_pool_size - CPSW_MAX_QUEUES))
 		return -EINVAL;
 
-	if (ering->rx_pending == cpdma_get_num_rx_descs(cpsw->dma))
+	descs_num = cpdma_get_num_rx_descs(cpsw->dma);
+	if (ering->rx_pending == descs_num)
 		return 0;
 
 	cpsw_suspend_data_pass(ndev);
 
-	cpdma_set_num_rx_descs(cpsw->dma, ering->rx_pending);
+	ret = cpdma_set_num_rx_descs(cpsw->dma, ering->rx_pending);
+	if (ret) {
+		if (cpsw_resume_data_pass(ndev))
+			goto err;
 
-	if (cpsw->usage_count)
-		cpdma_chan_split_pool(cpsw->dma);
+		return ret;
+	}
 
 	ret = cpsw_resume_data_pass(ndev);
 	if (!ret)
 		return 0;
-
+err:
+	cpdma_set_num_rx_descs(cpsw->dma, descs_num);
 	dev_err(cpsw->dev, "cannot set ring params, closing device\n");
 	dev_close(ndev);
 	return ret;