Re: [PATCH v2 1/1] media: i2c: ov02c10: Keep power on and use reset for power management

[Hans de Goede <hansg@kernel.org>]

Hi,

On 26-Jan-26 13:48, Saikiran B wrote:
> I used a 2ms delay for the initial reset assertion.

I think that what Bryan means is you need a 5ms delay between
asserting reset/xshutdown and enabling the regulators to make
sure that the sensor sees the reset signal high before
the regulators are enabled.

Regards,

Hans




> On Mon, Jan 26, 2026 at 6:11 PM Bryan O'Donoghue
> <bryan.odonoghue@linaro.org> wrote:
>>
>> On 26/01/2026 12:24, Saikiran B wrote:
>>> Yes, I implemented your suggested sequence in power_on():
>>>
>>> Assert XSHUTDOWN (Reset GPIO = 1)
>>
>> +5 milliseconds
>>
>>> Enable Regulators
>>> Enable Clock
>>> Wait 2ms+
>>> Release XSHUTDOWN (Reset GPIO = 0)
>>>
>>> Even with this sequence, the brownout prevents detection if the
>>> off-time was ~2.3s (I got this 2.3s number by conducting extensive
>>> stress tests on the platform starting from 50ms to 3s. At 2.3s the
>>> success rate was 100%. Anything below 2.3s, the sensor entered a
>>> brownout state atleast once.)
>>>
>>> Thanks & Regards,
>>> Saikiran
>>
>> ?
>>
>> ---
>> bod