[PATCH] mdio_bus: don't use managed reset-controller

[PATCH] mdio_bus: don't use managed reset-controller

[David Bauer]

Geert Uytterhoeven reported that using devm_reset_controller_get leads
to a WARNING when probing a reset-controlled PHY. This is because the
device devm_reset_controller_get gets supplied is not actually the
one being probed.

Acquire an unmanaged reset-control as well as free the reset_control on
unregister to fix this.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
CC: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David Bauer <mail@david-bauer.net>
---
 drivers/net/phy/mdio_bus.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
index dbacb0031877..229e480179ff 100644
--- a/drivers/net/phy/mdio_bus.c
+++ b/drivers/net/phy/mdio_bus.c
@@ -62,8 +62,8 @@ static int mdiobus_register_reset(struct mdio_device *mdiodev)
 	struct reset_control *reset = NULL;
 
 	if (mdiodev->dev.of_node)
-		reset = devm_reset_control_get_exclusive(&mdiodev->dev,
-							 "phy");
+		reset = of_reset_control_get_exclusive(mdiodev->dev.of_node,
+						       "phy");
 	if (IS_ERR(reset)) {
 		if (PTR_ERR(reset) == -ENOENT || PTR_ERR(reset) == -ENOTSUPP)
 			reset = NULL;
@@ -107,6 +107,8 @@ int mdiobus_unregister_device(struct mdio_device *mdiodev)
 	if (mdiodev->bus->mdio_map[mdiodev->addr] != mdiodev)
 		return -EINVAL;
 
+	reset_control_put(mdiodev->reset_ctrl);
+
 	mdiodev->bus->mdio_map[mdiodev->addr] = NULL;
 
 	return 0;
-- 
2.24.0

Re: [PATCH] mdio_bus: don't use managed reset-controller

[Andrew Lunn]

On Fri, Nov 22, 2019 at 10:44:51PM +0100, David Bauer wrote:
> Geert Uytterhoeven reported that using devm_reset_controller_get leads
> to a WARNING when probing a reset-controlled PHY. This is because the
> device devm_reset_controller_get gets supplied is not actually the
> one being probed.
> 
> Acquire an unmanaged reset-control as well as free the reset_control on
> unregister to fix this.
> 
> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
> CC: Andrew Lunn <andrew@lunn.ch>
> Signed-off-by: David Bauer <mail@david-bauer.net>

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

    Andrew

Re: [PATCH] mdio_bus: don't use managed reset-controller

[David Miller]

From: David Bauer <mail@david-bauer.net>
Date: Fri, 22 Nov 2019 22:44:51 +0100

> Geert Uytterhoeven reported that using devm_reset_controller_get leads
> to a WARNING when probing a reset-controlled PHY. This is because the
> device devm_reset_controller_get gets supplied is not actually the
> one being probed.
> 
> Acquire an unmanaged reset-control as well as free the reset_control on
> unregister to fix this.
> 
> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
> CC: Andrew Lunn <andrew@lunn.ch>
> Signed-off-by: David Bauer <mail@david-bauer.net>

Applied and queued up for -stable, thanks.