Re: [PATCH v4 1/2] tpm: Unify the send callback behaviour

[Jerry Snitselaar]

On Fri Feb 08 19, Jarkko Sakkinen wrote:
> The send() callback should never return length as it does not in every
> driver except tpm_crb in the success case. The reason is that the main
> transmit functionality only cares about whether the transmit was
> successful or not and ignores the count completely.
>
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
> ---
> drivers/char/tpm/st33zp24/st33zp24.c | 2 +-
> drivers/char/tpm/tpm_atmel.c         | 2 +-
> drivers/char/tpm/tpm_i2c_atmel.c     | 6 +++++-
> drivers/char/tpm/tpm_i2c_infineon.c  | 2 +-
> drivers/char/tpm/tpm_i2c_nuvoton.c   | 2 +-
> drivers/char/tpm/tpm_ibmvtpm.c       | 8 ++++----
> drivers/char/tpm/tpm_infineon.c      | 2 +-
> drivers/char/tpm/tpm_nsc.c           | 2 +-
> drivers/char/tpm/tpm_tis_core.c      | 2 +-
> drivers/char/tpm/tpm_vtpm_proxy.c    | 3 +--
> drivers/char/tpm/xen-tpmfront.c      | 2 +-
> 11 files changed, 18 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/char/tpm/st33zp24/st33zp24.c b/drivers/char/tpm/st33zp24/st33zp24.c
> index 64dc560859f2..13dc614b7ebc 100644
> --- a/drivers/char/tpm/st33zp24/st33zp24.c
> +++ b/drivers/char/tpm/st33zp24/st33zp24.c
> @@ -436,7 +436,7 @@ static int st33zp24_send(struct tpm_chip *chip, unsigned char *buf,
> 			goto out_err;
> 	}
>
> -	return len;
> +	return 0;
> out_err:
> 	st33zp24_cancel(chip);
> 	release_locality(chip);
> diff --git a/drivers/char/tpm/tpm_atmel.c b/drivers/char/tpm/tpm_atmel.c
> index 66a14526aaf4..a290b30a0c35 100644
> --- a/drivers/char/tpm/tpm_atmel.c
> +++ b/drivers/char/tpm/tpm_atmel.c
> @@ -105,7 +105,7 @@ static int tpm_atml_send(struct tpm_chip *chip, u8 *buf, size_t count)
> 		iowrite8(buf[i], priv->iobase);
> 	}
>
> -	return count;
> +	return 0;
> }
>
> static void tpm_atml_cancel(struct tpm_chip *chip)
> diff --git a/drivers/char/tpm/tpm_i2c_atmel.c b/drivers/char/tpm/tpm_i2c_atmel.c
> index 4720b2442ffe..aa11c8a1df5e 100644
> --- a/drivers/char/tpm/tpm_i2c_atmel.c
> +++ b/drivers/char/tpm/tpm_i2c_atmel.c
> @@ -65,7 +65,11 @@ static int i2c_atmel_send(struct tpm_chip *chip, u8 *buf, size_t len)
> 	dev_dbg(&chip->dev,
> 		"%s(buf=%*ph len=%0zx) -> sts=%d\n", __func__,
> 		(int)min_t(size_t, 64, len), buf, len, status);
> -	return status;
> +
> +	if (status < 0)
> +		return status;
> +
> +	return 0;
> }
>
> static int i2c_atmel_recv(struct tpm_chip *chip, u8 *buf, size_t count)
> diff --git a/drivers/char/tpm/tpm_i2c_infineon.c b/drivers/char/tpm/tpm_i2c_infineon.c
> index 3b490d9d90e7..3b4e9672ff6c 100644
> --- a/drivers/char/tpm/tpm_i2c_infineon.c
> +++ b/drivers/char/tpm/tpm_i2c_infineon.c
> @@ -588,7 +588,7 @@ static int tpm_tis_i2c_send(struct tpm_chip *chip, u8 *buf, size_t len)
> 	/* go and do it */
> 	iic_tpm_write(TPM_STS(tpm_dev.locality), &sts, 1);
>
> -	return len;
> +	return 0;
> out_err:
> 	tpm_tis_i2c_ready(chip);
> 	/* The TPM needs some time to clean up here,
> diff --git a/drivers/char/tpm/tpm_i2c_nuvoton.c b/drivers/char/tpm/tpm_i2c_nuvoton.c
> index 5700cc2ddee1..315a3b4548f7 100644
> --- a/drivers/char/tpm/tpm_i2c_nuvoton.c
> +++ b/drivers/char/tpm/tpm_i2c_nuvoton.c
> @@ -465,7 +465,7 @@ static int i2c_nuvoton_send(struct tpm_chip *chip, u8 *buf, size_t len)
> 	}
>
> 	dev_dbg(dev, "%s() -> %zd\n", __func__, len);
> -	return len;
> +	return 0;
> }
>
> static bool i2c_nuvoton_req_canceled(struct tpm_chip *chip, u8 status)
> diff --git a/drivers/char/tpm/tpm_ibmvtpm.c b/drivers/char/tpm/tpm_ibmvtpm.c
> index 07b5a487d0c8..757ca45b39b8 100644
> --- a/drivers/char/tpm/tpm_ibmvtpm.c
> +++ b/drivers/char/tpm/tpm_ibmvtpm.c
> @@ -139,14 +139,14 @@ static int tpm_ibmvtpm_recv(struct tpm_chip *chip, u8 *buf, size_t count)
> }
>
> /**
> - * tpm_ibmvtpm_send - Send tpm request
> - *
> + * tpm_ibmvtpm_send() - Send a TPM command
>  * @chip:	tpm chip struct
>  * @buf:	buffer contains data to send
>  * @count:	size of buffer
>  *
>  * Return:
> - *	Number of bytes sent or < 0 on error.
> + *   0 on success,
> + *   -errno on error
>  */
> static int tpm_ibmvtpm_send(struct tpm_chip *chip, u8 *buf, size_t count)
> {
> @@ -192,7 +192,7 @@ static int tpm_ibmvtpm_send(struct tpm_chip *chip, u8 *buf, size_t count)
> 		rc = 0;
> 		ibmvtpm->tpm_processing_cmd = false;
> 	} else
> -		rc = count;
> +		rc = 0;
>
> 	spin_unlock(&ibmvtpm->rtce_lock);
> 	return rc;
> diff --git a/drivers/char/tpm/tpm_infineon.c b/drivers/char/tpm/tpm_infineon.c
> index d8f10047fbba..97f6d4fe0aee 100644
> --- a/drivers/char/tpm/tpm_infineon.c
> +++ b/drivers/char/tpm/tpm_infineon.c
> @@ -354,7 +354,7 @@ static int tpm_inf_send(struct tpm_chip *chip, u8 * buf, size_t count)
> 	for (i = 0; i < count; i++) {
> 		wait_and_send(chip, buf[i]);
> 	}
> -	return count;
> +	return 0;
> }
>
> static void tpm_inf_cancel(struct tpm_chip *chip)
> diff --git a/drivers/char/tpm/tpm_nsc.c b/drivers/char/tpm/tpm_nsc.c
> index 5d6cce74cd3f..9bee3c5eb4bf 100644
> --- a/drivers/char/tpm/tpm_nsc.c
> +++ b/drivers/char/tpm/tpm_nsc.c
> @@ -226,7 +226,7 @@ static int tpm_nsc_send(struct tpm_chip *chip, u8 * buf, size_t count)
> 	}
> 	outb(NSC_COMMAND_EOC, priv->base + NSC_COMMAND);
>
> -	return count;
> +	return 0;
> }
>
> static void tpm_nsc_cancel(struct tpm_chip *chip)
> diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
> index 60e2038652b8..b9f64684c3fb 100644
> --- a/drivers/char/tpm/tpm_tis_core.c
> +++ b/drivers/char/tpm/tpm_tis_core.c
> @@ -481,7 +481,7 @@ static int tpm_tis_send_main(struct tpm_chip *chip, const u8 *buf, size_t len)
> 			goto out_err;
> 		}
> 	}
> -	return len;
> +	return 0;
> out_err:
> 	tpm_tis_ready(chip);
> 	return rc;
> diff --git a/drivers/char/tpm/tpm_vtpm_proxy.c b/drivers/char/tpm/tpm_vtpm_proxy.c
> index 26a2be555288..d74f3de74ae6 100644
> --- a/drivers/char/tpm/tpm_vtpm_proxy.c
> +++ b/drivers/char/tpm/tpm_vtpm_proxy.c
> @@ -335,7 +335,6 @@ static int vtpm_proxy_is_driver_command(struct tpm_chip *chip,
> static int vtpm_proxy_tpm_op_send(struct tpm_chip *chip, u8 *buf, size_t count)
> {
> 	struct proxy_dev *proxy_dev = dev_get_drvdata(&chip->dev);
> -	int rc = 0;
>
> 	if (count > sizeof(proxy_dev->buffer)) {
> 		dev_err(&chip->dev,
> @@ -366,7 +365,7 @@ static int vtpm_proxy_tpm_op_send(struct tpm_chip *chip, u8 *buf, size_t count)
>
> 	wake_up_interruptible(&proxy_dev->wq);
>
> -	return rc;
> +	return 0;
> }
>
> static void vtpm_proxy_tpm_op_cancel(struct tpm_chip *chip)
> diff --git a/drivers/char/tpm/xen-tpmfront.c b/drivers/char/tpm/xen-tpmfront.c
> index 1259e935fd58..4e2d00cb0d81 100644
> --- a/drivers/char/tpm/xen-tpmfront.c
> +++ b/drivers/char/tpm/xen-tpmfront.c
> @@ -173,7 +173,7 @@ static int vtpm_send(struct tpm_chip *chip, u8 *buf, size_t count)
> 		return -ETIME;
> 	}
>
> -	return count;
> +	return 0;
> }
>
> static int vtpm_recv(struct tpm_chip *chip, u8 *buf, size_t count)
> --
> 2.19.1

Does st33zp24_i2c_send need an update as well? It does 'return write8_reg()'.