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Date: Tue, 20 Feb 2024 16:04:40 +0000
From: Mark Brown <broonie@kernel.org>
To: Md Sadre Alam <quic_mdalam@quicinc.com>
Cc: andersson@kernel.org, konrad.dybcio@linaro.org, robh@kernel.org,
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Subject: Re: [PATCH 3/5] spi: spi-qpic: Add qpic spi nand driver support
Message-ID: <8422fb6a-edd4-4911-89b7-2974c197981b@sirena.org.uk>
References: <20240215134856.1313239-1-quic_mdalam@quicinc.com>
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 <21dde665-54b4-48e4-b963-1008ac890df3@sirena.org.uk>
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On Tue, Feb 20, 2024 at 05:24:43PM +0530, Md Sadre Alam wrote:
> On 2/15/2024 7:44 PM, Mark Brown wrote:
> > On Thu, Feb 15, 2024 at 07:18:54PM +0530, Md Sadre Alam wrote:

> > > +	if (op->cmd.opcode == SPINAND_READID) {
> > > +		snandc->buf_count = 4;
> > > +		read_reg_dma(snandc, NAND_READ_ID, 1, NAND_BAM_NEXT_SGL);
> > > +
> > > +		ret = submit_descs(snandc);
> > > +		if (ret)
> > > +			dev_err(snandc->dev, "failure in submitting descriptor for readid\n");
> > > +
> > > +		nandc_read_buffer_sync(snandc, true);
> > > +		memcpy(op->data.buf.in, snandc->reg_read_buf, snandc->buf_count);

> > These memcpy()s don't seem great, why aren't we just reading directly
> > into the output buffer?

>   This reg_read_buf is being used in common API so that it will be used by both
>   serial nand as well raw nand, so I can't directly use the output buffer since
>   internally CW mechanism I have to maintain in common API.

We have control over all the source code in the kernel so if there's
problems with the internal interfaces we can improve them.

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