[PATCH v4 2/7] phy: qcom-qmp: Enable pipe_clk before PHY initialization

From: Manu Gautam
Date: Thu Mar 29 2018 - 07:06:15 EST


QMP PHY for USB/PCIE requires pipe_clk for locking of
retime buffers at the pipe interface. Driver checks for
PHY_STATUS without enabling pipe_clk due to which
phy_init() fails with initialization timeout.
Though pipe_clk is output from PHY (after PLL is programmed
during initialization sequence) to GCC clock_ctl and then fed
back to PHY but for PHY_STATUS register to reflect successful
initialization pipe_clk from GCC must be present.
Since, clock driver now ignores status_check for pipe_clk on
clk_enable/disable, driver can safely enable/disable pipe_clk
from phy_init/exit.

Signed-off-by: Manu Gautam <mgautam@xxxxxxxxxxxxxx>
---
drivers/phy/qualcomm/phy-qcom-qmp.c | 22 ++++++++--------------
1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/drivers/phy/qualcomm/phy-qcom-qmp.c b/drivers/phy/qualcomm/phy-qcom-qmp.c
index 6470c5d..fddb1c9 100644
--- a/drivers/phy/qualcomm/phy-qcom-qmp.c
+++ b/drivers/phy/qualcomm/phy-qcom-qmp.c
@@ -793,19 +793,6 @@ static void qcom_qmp_phy_configure(void __iomem *base,
}
}

-static int qcom_qmp_phy_poweron(struct phy *phy)
-{
- struct qmp_phy *qphy = phy_get_drvdata(phy);
- struct qcom_qmp *qmp = qphy->qmp;
- int ret;
-
- ret = clk_prepare_enable(qphy->pipe_clk);
- if (ret)
- dev_err(qmp->dev, "pipe_clk enable failed, err=%d\n", ret);
-
- return ret;
-}
-
static int qcom_qmp_phy_com_init(struct qcom_qmp *qmp)
{
const struct qmp_phy_cfg *cfg = qmp->cfg;
@@ -974,6 +961,12 @@ static int qcom_qmp_phy_init(struct phy *phy)
}
}

+ ret = clk_prepare_enable(qphy->pipe_clk);
+ if (ret) {
+ dev_err(qmp->dev, "pipe_clk enable failed err=%d\n", ret);
+ goto err_clk_enable;
+ }
+
/* Tx, Rx, and PCS configurations */
qcom_qmp_phy_configure(tx, cfg->regs, cfg->tx_tbl, cfg->tx_tbl_num);
/* Configuration for other LANE for USB-DP combo PHY */
@@ -1019,6 +1012,8 @@ static int qcom_qmp_phy_init(struct phy *phy)
return ret;

err_pcs_ready:
+ clk_disable_unprepare(qphy->pipe_clk);
+err_clk_enable:
if (cfg->has_lane_rst)
reset_control_assert(qphy->lane_rst);
err_lane_rst:
@@ -1283,7 +1278,6 @@ static int phy_pipe_clk_register(struct qcom_qmp *qmp, struct device_node *np)
static const struct phy_ops qcom_qmp_phy_gen_ops = {
.init = qcom_qmp_phy_init,
.exit = qcom_qmp_phy_exit,
- .power_on = qcom_qmp_phy_poweron,
.set_mode = qcom_qmp_phy_set_mode,
.owner = THIS_MODULE,
};
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project