From 7e360fa0c0f3e7dd1aa8f2b574d7b461d0caf5e2 Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Wed, 11 Aug 2021 13:36:54 +0200 Subject: [PATCH] media: cec-pin: fix off-by-one SFT check The CEC pin framework has to wait for the CEC bus to be idle for the requested Signal Free Time before it can start a transmit. However, the check for that was off by one, so transmits would start one bit period (2.4ms) too late. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/cec/core/cec-pin.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/media/cec/core/cec-pin.c b/drivers/media/cec/core/cec-pin.c index 8c613aa..a60b6f0 100644 --- a/drivers/media/cec/core/cec-pin.c +++ b/drivers/media/cec/core/cec-pin.c @@ -957,7 +957,7 @@ static enum hrtimer_restart cec_pin_timer(struct hrtimer *timer) * so we can kick off the pending transmit. */ delta = ktime_us_delta(ts, pin->ts); - if (delta / CEC_TIM_DATA_BIT_TOTAL > + if (delta / CEC_TIM_DATA_BIT_TOTAL >= pin->tx_signal_free_time) { pin->tx_nacked = false; if (tx_custom_start(pin)) @@ -968,7 +968,7 @@ static enum hrtimer_restart cec_pin_timer(struct hrtimer *timer) cec_pin_low(pin); break; } - if (delta / CEC_TIM_DATA_BIT_TOTAL > + if (delta / CEC_TIM_DATA_BIT_TOTAL >= pin->tx_signal_free_time - 1) pin->state = CEC_ST_TX_WAIT; break; -- 2.7.4