[PATCH 1/1] scsi: ufs: make UFS Tx lane1 clock optional

From: Can Guo
Date: Mon Oct 08 2018 - 00:34:52 EST


From: Venkat Gopalakrishnan <venkatg@xxxxxxxxxxxxxx>

The UFS Tx lane1 clock could be muxed, hence keep it optional by ignoring
it if it is not provided in device tree.

Signed-off-by: Venkat Gopalakrishnan <venkatg@xxxxxxxxxxxxxx>
Signed-off-by: Subhash Jadavani <subhashj@xxxxxxxxxxxxxx>
Signed-off-by: Can Guo <cang@xxxxxxxxxxxxxx>
---
drivers/scsi/ufs/ufs-qcom.c | 46 ++++++++++++++++++++++++---------------------
1 file changed, 25 insertions(+), 21 deletions(-)

diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
index 2b38db2..a6e2ed3 100644
--- a/drivers/scsi/ufs/ufs-qcom.c
+++ b/drivers/scsi/ufs/ufs-qcom.c
@@ -85,13 +85,10 @@ static int ufs_qcom_host_clk_get(struct device *dev,
int err = 0;

clk = devm_clk_get(dev, name);
- if (IS_ERR(clk)) {
+ if (IS_ERR(clk))
err = PTR_ERR(clk);
- dev_err(dev, "%s: failed to get %s err %d",
- __func__, name, err);
- } else {
+ else
*clk_out = clk;
- }

return err;
}
@@ -113,10 +110,10 @@ static void ufs_qcom_disable_lane_clks(struct ufs_qcom_host *host)
if (!host->is_lane_clks_enabled)
return;

- if (host->hba->lanes_per_direction > 1)
+ if (host->tx_l1_sync_clk)
clk_disable_unprepare(host->tx_l1_sync_clk);
clk_disable_unprepare(host->tx_l0_sync_clk);
- if (host->hba->lanes_per_direction > 1)
+ if (host->rx_l1_sync_clk)
clk_disable_unprepare(host->rx_l1_sync_clk);
clk_disable_unprepare(host->rx_l0_sync_clk);

@@ -141,24 +138,21 @@ static int ufs_qcom_enable_lane_clks(struct ufs_qcom_host *host)
if (err)
goto disable_rx_l0;

- if (host->hba->lanes_per_direction > 1) {
+ if (host->rx_l1_sync_clk) {
err = ufs_qcom_host_clk_enable(dev, "rx_lane1_sync_clk",
host->rx_l1_sync_clk);
if (err)
goto disable_tx_l0;
-
- err = ufs_qcom_host_clk_enable(dev, "tx_lane1_sync_clk",
- host->tx_l1_sync_clk);
- if (err)
- goto disable_rx_l1;
}

+ /* The tx lane1 clk could be muxed, hence keep this optional */
+ if (host->tx_l1_sync_clk)
+ ufs_qcom_host_clk_enable(dev, "tx_lane1_sync_clk",
+ host->tx_l1_sync_clk);
+
host->is_lane_clks_enabled = true;
goto out;

-disable_rx_l1:
- if (host->hba->lanes_per_direction > 1)
- clk_disable_unprepare(host->rx_l1_sync_clk);
disable_tx_l0:
clk_disable_unprepare(host->tx_l0_sync_clk);
disable_rx_l0:
@@ -174,23 +168,33 @@ static int ufs_qcom_init_lane_clks(struct ufs_qcom_host *host)

err = ufs_qcom_host_clk_get(dev,
"rx_lane0_sync_clk", &host->rx_l0_sync_clk);
- if (err)
+ if (err) {
+ dev_err(dev, "%s: failed to get rx_lane0_sync_clk, err %d",
+ __func__, err);
goto out;
+ }

err = ufs_qcom_host_clk_get(dev,
"tx_lane0_sync_clk", &host->tx_l0_sync_clk);
- if (err)
+ if (err) {
+ dev_err(dev, "%s: failed to get tx_lane0_sync_clk, err %d",
+ __func__, err);
goto out;
+ }

/* In case of single lane per direction, don't read lane1 clocks */
if (host->hba->lanes_per_direction > 1) {
err = ufs_qcom_host_clk_get(dev, "rx_lane1_sync_clk",
&host->rx_l1_sync_clk);
- if (err)
+ if (err) {
+ dev_err(dev, "%s: failed to get rx_lane1_sync_clk, err %d",
+ __func__, err);
goto out;
+ }

- err = ufs_qcom_host_clk_get(dev, "tx_lane1_sync_clk",
- &host->tx_l1_sync_clk);
+ /* The tx lane1 clk could be muxed, hence keep this optional */
+ ufs_qcom_host_clk_get(dev, "tx_lane1_sync_clk",
+ &host->tx_l1_sync_clk);
}
out:
return err;
--
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