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From: Kamal Dasu <kdasu.kdev@gmail.com>
Date: Mon, 23 Jan 2017 18:41:03 -0500
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Subject: Re: [PATCH,
 1/2] mtd: m25p80: Let m25p80_read() fallback to spi transfer
To: Marek Vasut <marex@denx.de>
Cc: Michal Suchanek <hramrach@gmail.com>,
 Cyrille Pitchen <cyrille.pitchen@atmel.com>,
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"ret can never be > 0 , it is only 0 or negative "

I can fix this.

>>> This looks really fragile and special-casing EINVAL here doesn't scale.
>>> But still, if your controller driver is buggy, fix the driver, do not
>>> pollute core code with workarounds. If you do support this sort of
>>> accelerated read and it fails, it means something is seriously wrong.
>>> If you need to invoke regular SPI reads to complete under some obscure
>>> circumstances, do it from the driver, not here.
>>
>> I guess the other half of m25p80_read can be factored out and used as
>> fallback from either m25p80_read or the controller driver.
>
> I think I see what you mean, but care to show an RFC patch ?
>
> --

Its not the controller driver, but he hardware limitation with older
controller version. I have tried to see how I can do this better,
however when spi_flash_read() is called  cannot handle it within my
driver without returning from the function. I went over this with Mark
previously and this current solution seemed reasonable. Any other
solution outside of the generic driver would replicate a lot of code
unnecessarily.

> Best regards,
> Marek Vasut


Thanks
Kamal