linux-kernel - Re: [PATCH] NFC: trf7970a: disable all regulators on removal

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Date: Thu, 18 Apr 2024 10:12:16 +0200
From: Paul Geurts <paul_geurts@...e.nl>
To: Krzysztof Kozlowski <krzk@...nel.org>, mgreer@...malcreek.com,
 linux-wireless@...r.kernel.org, netdev@...r.kernel.org,
 linux-kernel@...r.kernel.org
Subject: Re: [PATCH] NFC: trf7970a: disable all regulators on removal

On 17-04-2024 15:15, Krzysztof Kozlowski wrote:
> On 16/04/2024 22:28, Paul Geurts wrote:
>> During module probe, regulator 'vin' and 'vdd-io' are used and enabled,
>> but the vdd-io regulator overwrites the 'vin' regulator pointer. During
>> remove, only the vdd-io is disabled, as the vin regulator pointer is not
>> available anymore. When regulator_put() is called during resource
>> cleanup a kernel warning is given, as the regulator is still enabled.
>>
>> Store the two regulators in separate pointers and disable both the
>> regulators on module remove.
>>
>> Fixes: 49d22c70aaf0 ("NFC: trf7970a: Add device tree option of 1.8 Volt IO voltage")
>>
>> Signed-off-by: Paul Geurts <paul_geurts@...e.nl>
> No blank lines between tags. Please look at existing commits (git log).
Will fix this, thanks
>
>> ---
>>  drivers/nfc/trf7970a.c | 42 +++++++++++++++++++++++-------------------
>>  1 file changed, 23 insertions(+), 19 deletions(-)
>>
>> diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c
>> index 7eb17f46a815..9e1a34e23af2 100644
>> --- a/drivers/nfc/trf7970a.c
>> +++ b/drivers/nfc/trf7970a.c
>> @@ -424,7 +424,8 @@ struct trf7970a {
>>  	enum trf7970a_state		state;
>>  	struct device			*dev;
>>  	struct spi_device		*spi;
>> -	struct regulator		*regulator;
>> +	struct regulator		*vin_regulator;
>> +	struct regulator		*vddio_regulator;
>>  	struct nfc_digital_dev		*ddev;
>>  	u32				quirks;
>>  	bool				is_initiator;
>> @@ -1883,7 +1884,7 @@ static int trf7970a_power_up(struct trf7970a *trf)
>>  	if (trf->state != TRF7970A_ST_PWR_OFF)
>>  		return 0;
>>  
>> -	ret = regulator_enable(trf->regulator);
>> +	ret = regulator_enable(trf->vin_regulator);
> That does not look like equivalent code. Previously this was vddio, right?
This is part of the original issue created by 49d22c70aaf0. This should be the VIN regulator, but the pointer override made it VDD-IO.
>
>
> Best regards,
> Krzysztof
>