[PATCH v2 1/3] spi: spi-mem: add automatic poll status functions
Patrice CHOTARD
patrice.chotard at foss.st.com
Mon May 17 00:29:24 PDT 2021
Hi Boris
On 5/10/21 11:22 AM, Boris Brezillon wrote:
> On Mon, 10 May 2021 10:46:48 +0200
> Patrice CHOTARD <patrice.chotard at foss.st.com> wrote:
>
>>>
>>>> +
>>>> + if (ctlr->mem_ops && ctlr->mem_ops->poll_status) {
>>>> + ret = spi_mem_access_start(mem);
>>>> + if (ret)
>>>> + return ret;
>>>> +
>>>> + reinit_completion(&ctlr->xfer_completion);
>>>> +
>>>> + ret = ctlr->mem_ops->poll_status(mem, op, mask, match,
>>>> + timeout_ms);
>>>> +
>>>> + ms = wait_for_completion_timeout(&ctlr->xfer_completion,
>>>> + msecs_to_jiffies(timeout_ms));
>>>
>>> Why do you need to wait here? I'd expect the poll_status to take care
>>> of this wait.
>>
>> It was a request from Mark Brown [1]. The idea is to implement
>> similar mechanism already used in SPI framework.
>
> Well, you have to choose, either you pass a timeout to ->poll_status()
> and let the driver wait for the status change (and return -ETIMEDOUT if
> it didn't happen in time), or you do it here and the driver only has to
> signal the core completion object. I think it's preferable to let the
> driver handle the timeout though, because you don't know how the
> status check will be implemented, and it's not like the
> reinit_completion()+wait_for_completion_timeout() done here would
> greatly simplify the drivers wait logic anyway.
>
Ok i will remove the reinit/wait_completion() as you suggested.
Thanks
Patrice
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