Re: [PATCH 2/2] spi: bcm-mspi: Add support for Broadcom MSPI driver.

From: Jonathan Richardson
Date: Thu May 14 2015 - 15:55:48 EST

On 15-05-14 12:08 PM, Mark Brown wrote:
> On Thu, May 14, 2015 at 11:19:01AM -0700, Scott Branden wrote:
>> On 15-05-14 03:31 AM, Mark Brown wrote:
>>> Chip vendors often say this sort of thing and then get surprised by what
>>> their users choose to do, and even if it only ever gets used with flash
>>> all it would take is some new flash command which can use full duplex
>>> for something. Please write the code so it at least tries to handle
>>> full duplex operation, if you can't test it fully that's not the end of
>>> the world. It doesn't look like it should be particularly difficult.
>> Yes, there is always room for improvements in code. In this case - it
>> really is not worth our time to add code we can't test. We try to deliver
>> code that we can test and actually works. Yes, if anyone needs to use the
> While I try to not apply code that has obvious problems with silent data
> corruption in it which is what we have just now.
>> mspi for full duplex operation code can be added in the future - it is
>> software. This block has gone through many generations of our SoCs and has
>> only been used for this purpose - the bootROM boots from this SPI only. It
>> is dedicated for this purpose.
> All it takes is one hardware engineer who sees a SPI controller and a
> GPIO they can use for chip select; I wouldn't be so sure that nobody
> ever fixed this up locally (or happened to use a device that only needed
> single duplex).

Hi Mark. Would it help if we just set the flags to half duplex using
SPI_MASTER_HALF_DUPLEX when we register the master?
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