[PATCH v3 1/2] can: m_can: Move mram init to mcan device setup

[Vivek Yadav]

> -----Original Message-----
> From: Marc Kleine-Budde <mkl at pengutronix.de>
> Sent: 24 November 2022 04:12
> To: Vivek Yadav <vivek.2311 at samsung.com>
> Cc: rcsekar at samsung.com; krzysztof.kozlowski+dt at linaro.org;
> wg at grandegger.com; davem at davemloft.net; edumazet at google.com;
> kuba at kernel.org; pabeni at redhat.com; pankaj.dubey at samsung.com;
> ravi.patel at samsung.com; alim.akhtar at samsung.com; linux-fsd at tesla.com;
> robh+dt at kernel.org; linux-can at vger.kernel.org; netdev at vger.kernel.org;
> linux-kernel at vger.kernel.org; linux-arm-kernel at lists.infradead.org; linux-
> samsung-soc at vger.kernel.org; devicetree at vger.kernel.org;
> aswani.reddy at samsung.com; sriranjani.p at samsung.com
> Subject: Re: [PATCH v3 1/2] can: m_can: Move mram init to mcan device
> setup
> 
> 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.
> 
> Why not call the RAM init directly from m_can_chip_config()?
> 
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 think only once during the probe is enough. 

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

From my understanding it's better to keep RAM init inside the probe and if there is a failure happened goes to CAN probe failure.
> Marc
Thanks for reviewing the patch.
> 
> --
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