From mboxrd@z Thu Jan 1 00:00:00 1970 From: dkos@cadence.com (Damian Kos) Date: Tue, 3 Jul 2018 11:02:18 +0100 Subject: [PATCH 07/12] drm/dp: fix drm_dp_link_train_clock_recovery_delay for DP 1.4 In-Reply-To: <1530612152-27555-1-git-send-email-dkos@cadence.com> References: <1530612152-27555-1-git-send-email-dkos@cadence.com> Message-ID: <1530612152-27555-8-git-send-email-dkos@cadence.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org From: Quentin Schulz In DP 1.4, interval between link status and adjust request read for the clock recovery phase is fixed to 100us whatever the value of the register is. Signed-off-by: Quentin Schulz Signed-off-by: Damian Kos --- drivers/gpu/drm/drm_dp_helper.c | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-) diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index b6a27ab..92f3880 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -152,6 +152,11 @@ void drm_dp_link_train_clock_recovery_delay(const u8 dpcd[DP_RECEIVER_CAP_SIZE]) unsigned int training_interval = dpcd[DP_TRAINING_AUX_RD_INTERVAL] & DP_TRAINING_AUX_RD_INTERVAL_MASK; + if (dpcd[DP_DPCD_REV] == 0x14) { + udelay(100); + return; + } + if (training_interval == 0) udelay(100); else -- 1.7.1