[PATCH] i2c: test off by one in {piix4,vt596}_transaction()

[Roel Kluin]

With `while (timeout++ < MAX_TIMEOUT)' timeout reaches MAX_TIMEOUT + 1 after the loop
This is probably unlikely to produce a problem.

Signed-off-by: Roel Kluin <roel....@gmail.com>
---
drivers/i2c/busses/i2c-piix4.c | 2 +-
drivers/i2c/busses/i2c-viapro.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c
index 1e245e9..d8e0df0 100644
--- a/drivers/i2c/busses/i2c-piix4.c
+++ b/drivers/i2c/busses/i2c-piix4.c
@@ -329,7 +329,7 @@ static int piix4_transaction(void)
msleep(1);

/* If the SMBus is still busy, we give up */
- if (timeout >= MAX_TIMEOUT) {
+ if (timeout > MAX_TIMEOUT) {
dev_err(&piix4_adapter.dev, "SMBus Timeout!\n");
result = -ETIMEDOUT;
}
diff --git a/drivers/i2c/busses/i2c-viapro.c b/drivers/i2c/busses/i2c-viapro.c
index e4b1543..8a2e0d5 100644
--- a/drivers/i2c/busses/i2c-viapro.c
+++ b/drivers/i2c/busses/i2c-viapro.c
@@ -168,7 +168,7 @@ static int vt596_transaction(u8 size)
} while ((temp & 0x01) && (timeout++ < MAX_TIMEOUT));

/* If the SMBus is still busy, we give up */
- if (timeout >= MAX_TIMEOUT) {
+ if (timeout > MAX_TIMEOUT) {
result = -ETIMEDOUT;
dev_err(&vt596_adapter.dev, "SMBus timeout!\n");
}
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[Jean Delvare]

That's right... but I'd rather change the loops to use "++timeout" and
leave the conditions as is (or maybe change it to "=="). I think it's
easier to read that way. Would that be OK with you?

--
Jean Delvare

[Roel Kluin]

With `while (timeout++ < MAX_TIMEOUT)' timeout reaches MAX_TIMEOUT + 1 after the loop
This is probably unlikely to produce a problem.

Signed-off-by: Roel Kluin <roel....@gmail.com>
---

> That's right... but I'd rather change the loops to use "++timeout" and
> leave the conditions as is (or maybe change it to "=="). I think it's
> easier to read that way. Would that be OK with you?

Ok,

drivers/i2c/busses/i2c-piix4.c | 4 ++--
drivers/i2c/busses/i2c-viapro.c | 4 ++--
2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c
index 1e245e9..e56e4b6 100644
--- a/drivers/i2c/busses/i2c-piix4.c
+++ b/drivers/i2c/busses/i2c-piix4.c
@@ -324,12 +324,12 @@ static int piix4_transaction(void)
else
msleep(1);

- while ((timeout++ < MAX_TIMEOUT) &&
+ while ((++timeout < MAX_TIMEOUT) &&
((temp = inb_p(SMBHSTSTS)) & 0x01))

msleep(1);

/* If the SMBus is still busy, we give up */
- if (timeout >= MAX_TIMEOUT) {

+ if (timeout == MAX_TIMEOUT) {

dev_err(&piix4_adapter.dev, "SMBus Timeout!\n");
result = -ETIMEDOUT;
}
diff --git a/drivers/i2c/busses/i2c-viapro.c b/drivers/i2c/busses/i2c-viapro.c

index e4b1543..a84a909 100644
--- a/drivers/i2c/busses/i2c-viapro.c
+++ b/drivers/i2c/busses/i2c-viapro.c
@@ -165,10 +165,10 @@ static int vt596_transaction(u8 size)
do {
msleep(1);
temp = inb_p(SMBHSTSTS);
- } while ((temp & 0x01) && (timeout++ < MAX_TIMEOUT));
+ } while ((temp & 0x01) && (++timeout < MAX_TIMEOUT));

/* If the SMBus is still busy, we give up */
- if (timeout >= MAX_TIMEOUT) {

+ if (timeout == MAX_TIMEOUT) {

result = -ETIMEDOUT;
dev_err(&vt596_adapter.dev, "SMBus timeout!\n");
}

[Jean Delvare]

Applied, thanks.

--
Jean Delvare