arc_emac: add clock handling
This adds ability for the arc_emac to really handle its supplying clock.
To get the needed clock-frequency either a real clock or the previous
clock-frequency property must be provided.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Max Schwarz <max.schwarz@online.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/arc/emac_main.c b/drivers/net/ethernet/arc/emac_main.c
index 9747dda..d647a7d 100644
--- a/drivers/net/ethernet/arc/emac_main.c
+++ b/drivers/net/ethernet/arc/emac_main.c
@@ -649,13 +649,6 @@
return -ENODEV;
}
- /* Get CPU clock frequency from device tree */
- if (of_property_read_u32(pdev->dev.of_node, "clock-frequency",
- &clock_frequency)) {
- dev_err(&pdev->dev, "failed to retrieve <clock-frequency> from device tree\n");
- return -EINVAL;
- }
-
/* Get IRQ from device tree */
irq = irq_of_parse_and_map(pdev->dev.of_node, 0);
if (!irq) {
@@ -687,13 +680,32 @@
}
dev_dbg(&pdev->dev, "Registers base address is 0x%p\n", priv->regs);
+ priv->clk = of_clk_get(pdev->dev.of_node, 0);
+ if (IS_ERR(priv->clk)) {
+ /* Get CPU clock frequency from device tree */
+ if (of_property_read_u32(pdev->dev.of_node, "clock-frequency",
+ &clock_frequency)) {
+ dev_err(&pdev->dev, "failed to retrieve <clock-frequency> from device tree\n");
+ err = -EINVAL;
+ goto out_netdev;
+ }
+ } else {
+ err = clk_prepare_enable(priv->clk);
+ if (err) {
+ dev_err(&pdev->dev, "failed to enable clock\n");
+ goto out_clkget;
+ }
+
+ clock_frequency = clk_get_rate(priv->clk);
+ }
+
id = arc_reg_get(priv, R_ID);
/* Check for EMAC revision 5 or 7, magic number */
if (!(id == 0x0005fd02 || id == 0x0007fd02)) {
dev_err(&pdev->dev, "ARC EMAC not detected, id=0x%x\n", id);
err = -ENODEV;
- goto out_netdev;
+ goto out_clken;
}
dev_info(&pdev->dev, "ARC EMAC detected with id: 0x%x\n", id);
@@ -708,7 +720,7 @@
ndev->name, ndev);
if (err) {
dev_err(&pdev->dev, "could not allocate IRQ\n");
- goto out_netdev;
+ goto out_clken;
}
/* Get MAC address from device tree */
@@ -729,7 +741,7 @@
if (!priv->rxbd) {
dev_err(&pdev->dev, "failed to allocate data buffers\n");
err = -ENOMEM;
- goto out_netdev;
+ goto out_clken;
}
priv->txbd = priv->rxbd + RX_BD_NUM;
@@ -741,7 +753,7 @@
err = arc_mdio_probe(pdev, priv);
if (err) {
dev_err(&pdev->dev, "failed to probe MII bus\n");
- goto out_netdev;
+ goto out_clken;
}
priv->phy_dev = of_phy_connect(ndev, phy_node, arc_emac_adjust_link, 0,
@@ -771,6 +783,12 @@
priv->phy_dev = NULL;
out_mdio:
arc_mdio_remove(priv);
+out_clken:
+ if (!IS_ERR(priv->clk))
+ clk_disable_unprepare(priv->clk);
+out_clkget:
+ if (!IS_ERR(priv->clk))
+ clk_put(priv->clk);
out_netdev:
free_netdev(ndev);
return err;
@@ -786,6 +804,12 @@
arc_mdio_remove(priv);
unregister_netdev(ndev);
netif_napi_del(&priv->napi);
+
+ if (!IS_ERR(priv->clk)) {
+ clk_disable_unprepare(priv->clk);
+ clk_put(priv->clk);
+ }
+
free_netdev(ndev);
return 0;