Re: [PATCH v11 04/14] tpm, tpm_tis: Do not skip reset of original interrupt vector

Jarkko Sakkinen
2022-11-28T01:26:21Z

On Thu, Nov 24, 2022 at 02:55:28PM +0100, Lino Sanfilippo wrote:
> From: Lino Sanfilippo <l.sanfilippo@kunbus.com>
>
> If in tpm_tis_probe_irq_single() an error occurs after the original
> interrupt vector has been read, restore the interrupts before the error is
> returned.
>
> Since the caller does not check the error value, return -1 in any case that
> the TPM_CHIP_FLAG_IRQ flag is not set. Since the return value of function
> tpm_tis_gen_interrupt() is not longer used, make it a void function.
>
> Fixes: 1107d065fdf1 ("tpm_tis: Introduce intermediate layer for TPM access")
> Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
> ---
> drivers/char/tpm/tpm_tis_core.c | 29 +++++++++++------------------
> 1 file changed, 11 insertions(+), 18 deletions(-)
>
> diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
> index 603b82ca56da..81b9726d3ed2 100644
> --- a/drivers/char/tpm/tpm_tis_core.c
> +++ b/drivers/char/tpm/tpm_tis_core.c
> @@ -729,7 +729,7 @@ static irqreturn_t tis_int_handler(int dummy, void *dev_id)
> return IRQ_HANDLED;
> }
>
> -static int tpm_tis_gen_interrupt(struct tpm_chip *chip)
> +static void tpm_tis_gen_interrupt(struct tpm_chip *chip)
> {
> const char *desc = "attempting to generate an interrupt";
> u32 cap2;
> @@ -738,7 +738,7 @@ static int tpm_tis_gen_interrupt(struct tpm_chip *chip)
>
> ret = request_locality(chip, 0);
> if (ret < 0)
> - return ret;
> + return;
>
> if (chip->flags & TPM_CHIP_FLAG_TPM2)
> ret = tpm2_get_tpm_pt(chip, 0x100, &cap2, desc);
> @@ -746,8 +746,6 @@ static int tpm_tis_gen_interrupt(struct tpm_chip *chip)
> ret = tpm1_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, desc, 0);
>
> release_locality(chip, 0);
> -
> - return ret;
> }
>
> /* Register the IRQ and issue a command that will cause an interrupt. If an
> @@ -777,42 +775,37 @@ static int tpm_tis_probe_irq_single(struct tpm_chip *chip, u32 intmask,
>
> rc = tpm_tis_write8(priv, TPM_INT_VECTOR(priv->locality), irq);
> if (rc < 0)
> - return rc;
> + goto restore_irqs;
>
> rc = tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &int_status);
> if (rc < 0)
> - return rc;
> + goto restore_irqs;
>
> /* Clear all existing */
> rc = tpm_tis_write32(priv, TPM_INT_STATUS(priv->locality), int_status);
> if (rc < 0)
> - return rc;
> -
> + goto restore_irqs;
> /* Turn on */
> rc = tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality),
> intmask | TPM_GLOBAL_INT_ENABLE);
> if (rc < 0)
> - return rc;
> + goto restore_irqs;
>
> clear_bit(TPM_TIS_IRQ_TESTED, &priv->flags);
>
> /* Generate an interrupt by having the core call through to
> * tpm_tis_send
> */
> - rc = tpm_tis_gen_interrupt(chip);
> - if (rc < 0)
> - return rc;
> + tpm_tis_gen_interrupt(chip);
>
> +restore_irqs:
> /* tpm_tis_send will either confirm the interrupt is working or it
> * will call disable_irq which undoes all of the above.
> */
> if (!(chip->flags & TPM_CHIP_FLAG_IRQ)) {
> - rc = tpm_tis_write8(priv, original_int_vec,
> - TPM_INT_VECTOR(priv->locality));
> - if (rc < 0)
> - return rc;
> -
> - return 1;
> + tpm_tis_write8(priv, original_int_vec,
> + TPM_INT_VECTOR(priv->locality));
> + return -1;
> }
>
> return 0;
> --
> 2.36.1
>

Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>

BR, Jarkko