[PATCH v3] i2c: npcm7xx: Fix timeout calculation

From: Tali Perry
Date: Sun Aug 30 2020 - 17:36:04 EST


timeout_usec value calculation was wrong, the calculated value
was in msec instead of usec.

Signed-off-by: Tali Perry <tali.perry1@xxxxxxxxx>
Reviewed-by: Avi Fishman <avifishman70@xxxxxxxxx>
---
drivers/i2c/busses/i2c-npcm7xx.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 75f07138a6fa..dfcf04e1967f 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -2093,8 +2093,12 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
}
}

- /* Adaptive TimeOut: astimated time in usec + 100% margin */
- timeout_usec = (2 * 10000 / bus->bus_freq) * (2 + nread + nwrite);
+ /*
+ * Adaptive TimeOut: estimated time in usec + 100% margin:
+ * 2: double the timeout for clock stretching case
+ * 9: bits per transaction (including the ack/nack)
+ */
+ timeout_usec = (2 * 9 * USEC_PER_SEC / bus->bus_freq) * (2 + nread + nwrite);
timeout = max(msecs_to_jiffies(35), usecs_to_jiffies(timeout_usec));
if (nwrite >= 32 * 1024 || nread >= 32 * 1024) {
dev_err(bus->dev, "i2c%d buffer too big\n", bus->num);

base-commit: d012a7190fc1fd72ed48911e77ca97ba4521bccd
--
2.22.0