[PATCH 3/5] spi: spi-qpic: Add qpic spi nand driver support

Md Sadre Alam quic_mdalam at quicinc.com
Wed Feb 21 02:36:28 PST 2024



On 2/20/2024 9:34 PM, Mark Brown wrote:
> 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.

Ok , will try to maintain CW mechanism uniform and remove from common API
and move to corresponding driver. Will try to fix in next patch.



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