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References: <20240207-spmi-multi-master-support-v1-0-ce57f301c7fd@linaro.org> <20240207-spmi-multi-master-support-v1-1-ce57f301c7fd@linaro.org>
In-Reply-To: <20240207-spmi-multi-master-support-v1-1-ce57f301c7fd@linaro.org>
From: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Date: Wed, 7 Feb 2024 01:55:39 +0200
Message-ID: <CAA8EJpqsJmv36=o1aTjVH6eMHXMg8BHNpiDvs+Q8YB23ezVGtQ@mail.gmail.com>
Subject: Re: [PATCH RFC 1/2] spmi: Add support for multi-master
To: Abel Vesa <abel.vesa@linaro.org>
Cc: Stephen Boyd <sboyd@kernel.org>, Matthias Brugger <matthias.bgg@gmail.com>, 
	Bjorn Andersson <andersson@kernel.org>, Konrad Dybcio <konrad.dybcio@linaro.org>, 
	AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>, linux-kernel@vger.kernel.org, 
	linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, 
	linux-mediatek@lists.infradead.org
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On Wed, 7 Feb 2024 at 01:34, Abel Vesa <abel.vesa@linaro.org> wrote:
>
> Some newer SPMI controllers support multiple bus masters.
> Such a master can control multiple slave devices. The generic
> framework needs to be able to pass on the master id to the
> controller-specific driver. So do that. The framework will
> check if the devicetree child nodes are actually bus masters
> and will register the devices for each master. The legacy
> approach will still be supported for backwards compatibility.

Please remind me, are those two actual bus musters driving a single
bus in parallel or two SPMI buses being handled by a single device? In
the latter case this implementation is incorrect. There should be
multiple spmi_controller instances, one for each bus. Allocate them in
a loop and set ctrl->dev.of_node after allocating.

>
> Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
> ---
>  drivers/spmi/spmi-mtk-pmif.c |  6 ++--
>  drivers/spmi/spmi-pmic-arb.c | 10 +++---
>  drivers/spmi/spmi.c          | 76 ++++++++++++++++++++++++++++++--------------
>  include/linux/spmi.h         | 10 +++---
>  4 files changed, 67 insertions(+), 35 deletions(-)

-- 
With best wishes
Dmitry