From cf27020d2f253bac6457d6833b97141030f0122a Mon Sep 17 00:00:00 2001 From: Alexandru M Stan Date: Wed, 1 Oct 2014 10:40:41 -0700 Subject: [PATCH] i2c: rk3x: fix 0 length write transfers i2cdetect -q was broken (everything was a false positive, and no transfers were actually being sent over i2c). The way it works is by sending a 0 length write request and checking for NACK. This patch fixes the 0 length writes and actually sends them. Reported-by: Doug Anderson Signed-off-by: Alexandru M Stan Tested-by: Doug Anderson Tested-by: Max Schwarz Signed-off-by: Wolfram Sang Cc: stable@kernel.org --- drivers/i2c/busses/i2c-rk3x.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-rk3x.c b/drivers/i2c/busses/i2c-rk3x.c index 93cfc837200b..b38b0529946a 100644 --- a/drivers/i2c/busses/i2c-rk3x.c +++ b/drivers/i2c/busses/i2c-rk3x.c @@ -238,7 +238,7 @@ static void rk3x_i2c_fill_transmit_buf(struct rk3x_i2c *i2c) for (i = 0; i < 8; ++i) { val = 0; for (j = 0; j < 4; ++j) { - if (i2c->processed == i2c->msg->len) + if ((i2c->processed == i2c->msg->len) && (cnt != 0)) break; if (i2c->processed == 0 && cnt == 0) -- GitLab