Re: [PATCH 2/5] tpm_tis_spi: Abort transfer when too many wait states are signaled

From: Jarkko Sakkinen
Date: Fri Feb 24 2017 - 07:58:42 EST


On Thu, Feb 16, 2017 at 04:08:23PM +0000, Peter Huewe wrote:
> Abort the transfer with ETIMEDOUT when the TPM signals more than
> TPM_RETRY wait states. Continuing with the transfer in this state
> will only lead to arbitrary failures in other parts of the code.
>
> Cc: <stable@xxxxxxxxxxxxxxx>
> Fixes: 0edbfea537d1 ("tpm/tpm_tis_spi: Add support for spi phy")
> Signed-off-by: Alexander Steffen <Alexander.Steffen@xxxxxxxxxxxx>
> Signed-off-by: Peter Huewe <peter.huewe@xxxxxxxxxxxx>

Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>

/Jarkko

> ---
> drivers/char/tpm/tpm_tis_spi.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/drivers/char/tpm/tpm_tis_spi.c b/drivers/char/tpm/tpm_tis_spi.c
> index 6e1a3c43f621..d782b9974c14 100644
> --- a/drivers/char/tpm/tpm_tis_spi.c
> +++ b/drivers/char/tpm/tpm_tis_spi.c
> @@ -101,6 +101,11 @@ static int tpm_tis_spi_transfer(struct tpm_tis_data *data, u32 addr, u8 len,
> goto exit;
> }
>
> + if (i == TPM_RETRY) {
> + ret = -ETIMEDOUT;
> + goto exit;
> + }
> +
> spi_xfer.cs_change = 0;
> spi_xfer.len = len;
>
> --
> 2.7.4
>