[PATCH v4 13/16] phy: qcom-qmp-pcie: fix initialisation reset

Johan Hovold johan+linaro at kernel.org
Fri Oct 28 06:36:00 PDT 2022


Add the missing delay after asserting reset. This is specifically needed
for the reset to have any effect on SC8280XP.

The vendor driver uses a 1 ms delay, but that seems a bit excessive.
Instead use a 200 us delay which appears to be more than enough and also
matches the UFS reset delay added by commit 870b1279c7a0 ("scsi:
ufs-qcom: Add reset control support for host controller").

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
Signed-off-by: Johan Hovold <johan+linaro at kernel.org>
---
 drivers/phy/qualcomm/phy-qcom-qmp-pcie.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c b/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
index 2f4bdef73395..9c8e009033f1 100644
--- a/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
+++ b/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
@@ -1866,6 +1866,8 @@ static int qmp_pcie_init(struct phy *phy)
 		goto err_disable_regulators;
 	}
 
+	usleep_range(200, 300);
+
 	ret = reset_control_bulk_deassert(cfg->num_resets, qmp->resets);
 	if (ret) {
 		dev_err(qmp->dev, "reset deassert failed\n");
-- 
2.37.3




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