[PATCH net v3 14/14] net: pse-pd: pd692x0: defer probe while a manager supply is unresolved

[Carlo Szelinsky <github@szelinsky.de>]

pd692x0_req_managers_pw_budget() uses each manager regulator's supply
without a NULL check. The supply is NULL while the vmain regulator is
described but not registered yet, because regulator_register() does not
wait for its supply. Probe then crashes.

Return -EPROBE_DEFER in that case.

Found by code inspection. Not reproduced.

Fixes: 359754013e6a ("net: pse-pd: pd692x0: Add support for PSE PI priority feature")
Reviewed-by: Kory Maincent <kory.maincent@bootlin.com>
Signed-off-by: Carlo Szelinsky <github@szelinsky.de>
---
 drivers/net/pse-pd/pd692x0.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/net/pse-pd/pd692x0.c b/drivers/net/pse-pd/pd692x0.c
index 34f0dfbccd06..568789bd912f 100644
--- a/drivers/net/pse-pd/pd692x0.c
+++ b/drivers/net/pse-pd/pd692x0.c
@@ -1056,6 +1056,15 @@ pd692x0_req_managers_pw_budget(struct pd692x0_priv *priv)
 		struct regulator *supply = priv->manager_reg[i]->supply;
 		int pw_budget;
 
+		/* The regulator core registers the manager regulator even
+		 * when its vmain supply cannot be resolved yet and retries
+		 * later, leaving ->supply NULL until then.
+		 */
+		if (!supply)
+			return dev_err_probe(&priv->client->dev, -EPROBE_DEFER,
+					     "manager %d: vmain supply not resolved\n",
+					     i);
+
 		pw_budget = regulator_get_unclaimed_power_budget(supply);
 		if (!pw_budget)
 			/* Do nothing if no power budget */
-- 
2.43.0