Re: [PATCH] mfd: cros ec: spi: Fix "in progress" error signaling

[Jon Hunter <jonathanh@nvidia.com>]

Hi Lee,

On 14/11/17 17:00, Shawn N wrote:
> On Wed, Sep 27, 2017 at 3:19 PM, Brian Norris <briannorris@chromium.org> wrote:
>> On Wed, Sep 27, 2017 at 02:35:27PM -0700, Shawn Nematbakhsh wrote:
>>> For host commands that take a long time to process, cros ec can return
>>> early by signaling a EC_RES_IN_PROGRESS result. The host must then poll
>>> status with EC_CMD_GET_COMMS_STATUS until completion of the command.
>>>
>>> None of the above applies when data link errors are encountered. When
>>> errors such as EC_SPI_PAST_END are encountered during command
>>> transmission, it usually means the command was not received by the EC.
>>> Treating such errors as if they were 'EC_RES_IN_PROGRESS' results is
>>> almost always the wrong decision, and can result in host commands
>>> silently being lost.
>>>
>>> Reported-and-tested-by: Jon Hunter <jonathanh@nvidia.com>
>>> Signed-off-by: Shawn Nematbakhsh <shawnn@chromium.org>
>>> ---
>>>  drivers/mfd/cros_ec_spi.c | 52 ++++++++++++++++++++++-------------------------
>>>  1 file changed, 24 insertions(+), 28 deletions(-)
>>
>> I'm still not sure I understand the full extent of the
>> originally-reported error (it's still likely a SPI transport issue?),
>> but I believe this patch is good anyway:
>>
>> Reviewed-by: Brian Norris <briannorris@chromium.org>
> 
> Jon tracked down the root cause of the originally-reported error, but
> we should still land this patch, as it fixes error signaling that was
> previously broken.

Can you also queue this one as a fix for v4.15?

Cheers
Jon

-- 
nvpublic