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

From: Andy Shevchenko <andriy.shevchenko@intel.com>
To: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: jic23@kernel.org, dlechner@baylibre.com, nuno.sa@analog.com,
	andy@kernel.org, arnd@arndb.de, gregkh@linuxfoundation.org,
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	sre@kernel.org, sboyd@kernel.org, krzk@kernel.org,
	dmitry.baryshkov@oss.qualcomm.com, quic_wcheng@quicinc.com,
	melody.olvera@oss.qualcomm.com, quic_nsekar@quicinc.com,
	ivo.ivanov.ivanov1@gmail.com, abelvesa@kernel.org,
	luca.weiss@fairphone.com, konrad.dybcio@oss.qualcomm.com,
	mitltlatltl@gmail.com, krishna.kurapati@oss.qualcomm.com,
	linux-arm-msm@vger.kernel.org, linux-iio@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-phy@lists.infradead.org,
	linux-pm@vger.kernel.org, kernel@collabora.com
Subject: Re: [PATCH v7 05/10] nvmem: qcom-spmi-sdam: Migrate to devm_spmi_subdevice_alloc_and_add()
Date: Wed, 14 Jan 2026 11:42:17 +0200	[thread overview]
Message-ID: <aWdk-RP-59cJeCBo@smile.fi.intel.com> (raw)
In-Reply-To: <647b4acc-3310-4329-ac7a-77e86bab74a3@collabora.com>

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?

> > > > > > > +		.fast_io = true,
> > > > > > > +	};

-- 
With Best Regards,
Andy Shevchenko