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From:   "Vivek Yadav" <vivek.2311@samsung.com>
To:     "'Marc Kleine-Budde'" <mkl@pengutronix.de>
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In-Reply-To: <20221123224146.iic52cuhhnwqk2te@pengutronix.de>
Subject: RE: [PATCH v3 1/2] can: m_can: Move mram init to mcan device setup
Date:   Thu, 24 Nov 2022 14:36:48 +0530
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> -----Original Message-----
> From: Marc Kleine-Budde <mkl=40pengutronix.de>
> Sent: 24 November 2022 04:12
> To: Vivek Yadav <vivek.2311=40samsung.com>
> Cc: rcsekar=40samsung.com; krzysztof.kozlowski+dt=40linaro.org;
> wg=40grandegger.com; davem=40davemloft.net; edumazet=40google.com;
> kuba=40kernel.org; pabeni=40redhat.com; pankaj.dubey=40samsung.com;
> ravi.patel=40samsung.com; alim.akhtar=40samsung.com; linux-fsd=40tesla.co=
m;
> robh+dt=40kernel.org; linux-can=40vger.kernel.org; netdev=40vger.kernel.o=
rg;
> linux-kernel=40vger.kernel.org; linux-arm-kernel=40lists.infradead.org; l=
inux-
> samsung-soc=40vger.kernel.org; devicetree=40vger.kernel.org;
> aswani.reddy=40samsung.com; sriranjani.p=40samsung.com
> Subject: Re: =5BPATCH v3 1/2=5D can: m_can: Move mram init to mcan device
> setup
>=20
> On 22.11.2022 16:24:54, Vivek Yadav wrote:
> > When we try to access the mcan message ram addresses, hclk is gated by
> > any other drivers or disabled, because of that probe gets failed.
> >
> > Move the mram init functionality to mcan device setup called by mcan
> > class register from mcan probe function, by that time clocks are
> > enabled.
>=20
> Why not call the RAM init directly from m_can_chip_config()?
>=20
m_can_chip_config function is called from m_can open.

Configuring RAM init every time we open the CAN instance is not needed, I t=
hink only once during the probe is enough.=20

If message RAM init failed then fifo Transmit and receive will fail and the=
re will be no communication. So there is no point to =22open and Configure =
CAN chip=22.

=46rom my understanding it's better to keep RAM init inside the probe and i=
f there is a failure happened goes to CAN probe failure.
> Marc
Thanks for reviewing the patch.
>=20
> --
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