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

On Sat, Feb 9, 2019 at 11:20 AM Jerry Snitselaar [off-list ref] wrote:

On Fri Feb 08 19, Jarkko Sakkinen wrote:

quoted

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@vger.kernel.org
Signed-off-by: Jarkko Sakkinen <redacted>
---
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()'.

Disregard this question. It is st33zp24_send that would be the one to
change, and you already dealt with that.