Re: [PATCH v7 05/10] nvmem: qcom-spmi-sdam: Migrate to devm_spmi_subdevice_alloc_and_add()

From: Konrad Dybcio

Date: Wed Jan 14 2026 - 04:47:26 EST


On 1/14/26 10:42 AM, Andy Shevchenko wrote:
> On Wed, Jan 14, 2026 at 10:09:45AM +0100, AngeloGioacchino Del Regno wrote:
>> Il 14/01/26 10:07, Andy Shevchenko ha scritto:
>>> On Wed, Jan 14, 2026 at 10:03:57AM +0100, AngeloGioacchino Del Regno wrote:
>>>> Il 14/01/26 10:00, Andy Shevchenko ha scritto:
>>>>> On Wed, Jan 14, 2026 at 09:59:40AM +0100, AngeloGioacchino Del Regno wrote:
>>>>>> Il 14/01/26 09:56, Andy Shevchenko ha scritto:
>>>>>>> On Wed, Jan 14, 2026 at 09:39:52AM +0100, AngeloGioacchino Del Regno wrote:
>
> ...
>
>>>>>>>> + struct regmap_config sdam_regmap_config = {
>>>>>>>> + .reg_bits = 16,
>>>>>>>> + .val_bits = 8,
>>>>>>>
>>>>>>>> + .max_register = 0x100,
>>>>>>>
>>>>>>> Are you sure? This might be a bad naming, but here max == the last accessible.
>>>>>>> I bet it has to be 0xff (but since the address is 16-bit it might be actually
>>>>>>> 257 registers, but sounds very weird).
>>>>>>
>>>>>> Yes, I'm sure.
>>>>>
>>>>> So, what is resided on address 0x100 ?
>>>>
>>>> I don't remember, this is research from around 5 months ago, when I've sent
>>>> the v1 of this.
>>>>
>>>> If you really want though, I can incorrectly set max_register to 0xff.
>>>
>>> Why incorrectly? Can you dig into the datasheet and check, please? We don't
>>> know what is the 0x100 address means.
>>
>> I don't have any datasheets for Qualcomm IPs.
>
> Hmm... Can we have somebody from QC to check on this?
> Perhaps Dmitry?

0xe6 is the last usable register today

But I wouldn't mind either 0xff or 0x100 because I don't want
anyone to pull their hair out if a regmap access is dropped some day..

Konrad