Re: [PATCH 0/2] tpm: add driver for cr50 on SPI

From: Jason Gunthorpe
Date: Thu Jul 14 2016 - 23:28:25 EST


On Thu, Jul 14, 2016 at 07:50:26PM -0700, Andrey Pronin wrote:
> Yes, it has a TCG-compliant interface, however, there are several things
> specific to this device:
> - need to ensure a certain delay between spi transactions, or else
> the chip can miss several first bytes.
> - if there is no spi activity for this chip, it may go to sleep, and
> needs to be waken up before sending further commands.
> - it has some vendor-specific registers accessible from spi bus.

This all needs to be commented clearly in the driver..

The chip sounds pretty broken...

Jason