On Tue, 2018-06-26 at 15:30 -0400, Stefan Berger wrote:
> Some subsystems that got a hold of a TPM chip through tpm_default_chip()
> need a way to release the reference to the TPM chip when they shut down.
> The tpm_put_chip() function enables this.
>
> Signed-off-by: Stefan Berger <stefanb@xxxxxxxxxxxxxxxxx>
> ---
> drivers/char/tpm/tpm-chip.c | 10 ++++++++++
> include/linux/tpm.h | 4 ++++
> 2 files changed, 14 insertions(+)
>
> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
> index 46caadca916a..c744289d82e0 100644
> --- a/drivers/char/tpm/tpm-chip.c
> +++ b/drivers/char/tpm/tpm-chip.c
> @@ -80,6 +80,16 @@ void tpm_put_ops(struct tpm_chip *chip)
> }
> EXPORT_SYMBOL_GPL(tpm_put_ops);
>
> +/**
> + * tpm_put_chip() - Releae a ref to the tpm_chip
> + * @chip: Chip to put
> + */
> +void tpm_put_chip(struct tpm_chip *chip)
> +{
> + put_device(&chip->dev);
> +}
> +EXPORT_SYMBOL_GPL(tpm_put_chip);
> +
> /**
> * tpm_default_chip() - find a TPM chip and get a reference to it
> */
> diff --git a/include/linux/tpm.h b/include/linux/tpm.h
> index e0e51c49a0e6..889dafe739e1 100644
> --- a/include/linux/tpm.h
> +++ b/include/linux/tpm.h
> @@ -62,6 +62,7 @@ extern int tpm_unseal_trusted(struct tpm_chip *chip,
> struct trusted_key_payload *payload,
> struct trusted_key_options *options);
> extern struct tpm_chip *tpm_default_chip(void);
> +extern void tpm_put_chip(struct tpm_chip *chip);
> #else
> static inline int tpm_is_tpm2(struct tpm_chip *chip)
> {
> @@ -101,5 +102,8 @@ static inline struct tpm_chip *tpm_default_chip(void)
> {
> return NULL;
> }
> +static inline void tpm_put_chip(struct tpm_chip *chip)
> +{
> +}
> #endif
> #endif
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
/Jarkko
