On Fri, 13 Mar 2026 17:24:31 +0000
Conor Dooley [off-list ref] wrote:

On Fri, Mar 13, 2026 at 09:31:02PM +0800, Robby Cai wrote:

quoted

The FP9931 requires a mandatory "vin" power supply to operate.
Replace devm_regulator_get_optional() with devm_regulator_get() to
enforce this mandatory dependency.

Fixes: 12d821bd13d42 ("regulator: Add FP9931/JD9930 driver")
Signed-off-by: Robby Cai <redacted>
---
 drivers/regulator/fp9931.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/regulator/fp9931.c b/drivers/regulator/fp9931.c
index 69b3c712e5d58..d4ba818ec2c15 100644
--- a/drivers/regulator/fp9931.c
+++ b/drivers/regulator/fp9931.c

@@ -444,7 +444,7 @@ static int fp9931_probe(struct i2c_client *client)
 		return dev_err_probe(&client->dev, PTR_ERR(data->regmap),
 				     "failed to allocate regmap!\n");
 
-	data->vin_reg = devm_regulator_get_optional(&client->dev, "vin");
+	data->vin_reg = devm_regulator_get(&client->dev, "vin");  

And this isn't an ABI break because the regulator core will invent a
dummy regulator?

On most devices I see a dummy regulator somewhere.

What IMHO itches more is that one has to invent a regulator in devicetree
if the property is mandatory and the supply is not known, you have to add
a dummy regulator in the devicetree to make dtbs_check happy.

Regards,
Andreas