Re: TPM driver breaks S3 suspend

[Jarkko Sakkinen]

On Thu, Mar 15, 2018 at 06:11:19PM +0800, Daniel Drake wrote:
> Hi,
> 
> Sorry for the delayed response.
> 
> Unfortunately we had to return the affected machine to the vendor
> (Acer Veriton X4110G) although given we have a fairly complete
> understanding of the problem, perhaps we can find and push a fix
> anyway.
> 
> Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx> wrote:
> > Can you try it on git://git.infradead.org/users/jjs/linux-tpmdd.git ?
> > Maybe it is related to the LPC #CLKRUN issues we've had.
> 
> I don't see anything relevant in that git tree, and it seems like
> a distant issue from the CLKRUN changes that have been made.
> 
> To recap, the first suspend works OK, and then the TPM shows shows the
> following message on the first resume:
>   tpm tpm0: A TPM error(38) occured continue selftest
> And error(38) is TPM_ERR_INVALID_POSTINIT which means the TPM is
> not in the correct state. Then the following suspend will always
> fail with the following messages.
>   tpm tpm0: Error (38) sending savestate before suspend
>   PM: Device 00:0b failed to suspend: error 38
> 
> tpm_crb is the driver here (not tpm2).
> 
> This exact problem was also discussed in depth years ago at
> https://lists.gt.net/linux/kernel/1358716
> 
> The patch that we used to avoid the issue is below. What do you think?

I think this would work for me.

/Jarkko

> 
> Thanks
> Daniel
> 
> 
> ---
>  drivers/char/tpm/tpm-interface.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
> index 1d6729be4cd6..444ae2df4a06 100644
> --- a/drivers/char/tpm/tpm-interface.c
> +++ b/drivers/char/tpm/tpm-interface.c
> @@ -953,6 +953,10 @@ int tpm_do_selftest(struct tpm_chip *chip)
>  	loops = jiffies_to_msecs(duration) / delay_msec;
>  
>  	rc = tpm_continue_selftest(chip);
> +	if (rc == TPM_ERR_INVALID_POSTINIT) {
> +		chip->flags |= TPM_CHIP_FLAG_ALWAYS_POWERED;
> +		dev_info(&chip->dev, "TPM not ready (%d)\n", rc);
> +	}
>  	/* This may fail if there was no TPM driver during a suspend/resume
>  	 * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
>  	 */
> -- 
> 2.14.1
>