[PATCH AUTOSEL 4.19 158/158] net: mvmdio: defer probe of orion-mdio if a clock is not ready

[Sasha Levin]

From: Josua Mayer <josua@xxxxxxxxxxxxx>

[ Upstream commit 433a06d7d74e677c40b1148c70c48677ff62fb6b ]

Defer probing of the orion-mdio interface when getting a clock returns
EPROBE_DEFER. This avoids locking up the Armada 8k SoC when mdio is used
before all clocks have been enabled.

Signed-off-by: Josua Mayer <josua@xxxxxxxxxxxxx>
Reviewed-by: Andrew Lunn <andrew@xxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/ethernet/marvell/mvmdio.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/net/ethernet/marvell/mvmdio.c b/drivers/net/ethernet/marvell/mvmdio.c
index c5dac6bd2be4..903836e334d8 100644
--- a/drivers/net/ethernet/marvell/mvmdio.c
+++ b/drivers/net/ethernet/marvell/mvmdio.c
@@ -321,6 +321,10 @@ static int orion_mdio_probe(struct platform_device *pdev)
 
 	for (i = 0; i < ARRAY_SIZE(dev->clk); i++) {
 		dev->clk[i] = of_clk_get(pdev->dev.of_node, i);
+		if (PTR_ERR(dev->clk[i]) == -EPROBE_DEFER) {
+			ret = -EPROBE_DEFER;
+			goto out_clk;
+		}
 		if (IS_ERR(dev->clk[i]))
 			break;
 		clk_prepare_enable(dev->clk[i]);
@@ -362,6 +366,7 @@ static int orion_mdio_probe(struct platform_device *pdev)
 	if (dev->err_interrupt > 0)
 		writel(0, dev->regs + MVMDIO_ERR_INT_MASK);
 
+out_clk:
 	for (i = 0; i < ARRAY_SIZE(dev->clk); i++) {
 		if (IS_ERR(dev->clk[i]))
 			break;
-- 
2.20.1