Re: [PATCH v3 3/5] tpm: migrate tpm2_probe() to use struct tpm_buf

[Mimi Zohar <zohar@linux.vnet.ibm.com>]

Hi Jarrko,

On Mon, 2018-03-05 at 18:56 +0200, Jarkko Sakkinen wrote:
> In order to make struct tpm_buf the first class object for constructing TPM
> commands, migrate tpm2_probe() to use it.
> 
> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

With this patch, the Pi doesn't find the TPM.  I'm seeing the
following line in dmesg.

[    1.087414] tpm_tis_spi: probe of spi0.0 failed with error 256

Mimi

> ---
>  drivers/char/tpm/tpm2-cmd.c | 27 +++++++++++++++------------
>  1 file changed, 15 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
> index abe6ef4a7a0b..890d83c5c78b 100644
> --- a/drivers/char/tpm/tpm2-cmd.c
> +++ b/drivers/char/tpm/tpm2-cmd.c
> @@ -851,22 +851,25 @@ static int tpm2_do_selftest(struct tpm_chip *chip)
>   */
>  int tpm2_probe(struct tpm_chip *chip)
>  {
> -	struct tpm2_cmd cmd;
> +	struct tpm_output_header *out;
> +	struct tpm_buf buf;
>  	int rc;
> 
> -	cmd.header.in = tpm2_get_tpm_pt_header;
> -	cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
> -	cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(0x100);
> -	cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
> -
> -	rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, 0, NULL);
> -	if (rc <  0)
> +	rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
> +	if (rc)
>  		return rc;
> -
> -	if (be16_to_cpu(cmd.header.out.tag) == TPM2_ST_NO_SESSIONS)
> +	tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
> +	tpm_buf_append_u32(&buf, TPM_PT_TOTAL_COMMANDS);
> +	tpm_buf_append_u32(&buf, 1);
> +	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0, NULL);
> +	if (rc <  0)
> +		goto out;
> +	out = (struct tpm_output_header *)buf.data;
> +	if (be16_to_cpu(out->tag) == TPM2_ST_NO_SESSIONS)
>  		chip->flags |= TPM_CHIP_FLAG_TPM2;
> -
> -	return 0;
> +out:
> +	tpm_buf_destroy(&buf);
> +	return rc;
>  }
>  EXPORT_SYMBOL_GPL(tpm2_probe);
>