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 <[email protected]> > Signed-off-by: Shawn Nematbakhsh <[email protected]> > --- > 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 <[email protected]> I wonder if we should tone down the BUG_ON()'s in drivers/mfd/cros_ec* and drivers/platform/chrome/* too. That's basically a no-no these days, as all of these type of things should be able to gracefully propagate errors, no matter how "unlikely" it should be to see a crazy protocol version number or a bad message length.
