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authorPeter Huewe <peterhuewe@gmx.de>2013-03-04 22:17:15 +0100
committerKent Yoder <key@linux.vnet.ibm.com>2013-04-12 12:17:29 -0500
commit6aa4ef4dab92fc8d4f0e5ea735ae3fd520af510b (patch)
tree41649e3734eb73ee10ddda927b4d1afb0b5c17ff /drivers/char/tpm/tpm_i2c_infineon.c
parent21dc02eab989d260fd9e22b72a29ac139a727cdd (diff)
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tpm/tpm_i2c_infineon: Add small comment about return value of __i2c_transfer
Kent Yoder indicated that the code might be a bit clearer with a comment here, so this patch adds a small explanation of the code. Signed-off-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
Diffstat (limited to 'drivers/char/tpm/tpm_i2c_infineon.c')
-rw-r--r--drivers/char/tpm/tpm_i2c_infineon.c9
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/char/tpm/tpm_i2c_infineon.c b/drivers/char/tpm/tpm_i2c_infineon.c
index d83bb8c0217b..37d5dcc10ea7 100644
--- a/drivers/char/tpm/tpm_i2c_infineon.c
+++ b/drivers/char/tpm/tpm_i2c_infineon.c
@@ -162,6 +162,10 @@ out:
/* take care of 'guard time' */
usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI);
+ /* __i2c_transfer returns the number of successfully transferred
+ * messages.
+ * So rc should be greater than 0 here otherwise we have an error.
+ */
if (rc <= 0)
return -EIO;
@@ -208,6 +212,11 @@ static int iic_tpm_write_generic(u8 addr, u8 *buffer, size_t len,
i2c_unlock_adapter(tpm_dev.client->adapter);
/* take care of 'guard time' */
usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI);
+
+ /* __i2c_transfer returns the number of successfully transferred
+ * messages.
+ * So rc should be greater than 0 here otherwise we have an error.
+ */
if (rc <= 0)
return -EIO;