[PATCH v5 3/7] phy: qcom-qusb2: Fix crash if nvmem cell not specified

From: Manu Gautam
Date: Wed May 02 2018 - 17:08:12 EST


Driver currently crashes due to NULL pointer deference
while updating PHY tune register if nvmem cell is NULL.
Since, fused value for Tune1/2 register is optional,
we'd rather bail out.

Fixes: ca04d9d3e1b1 ("phy: qcom-qusb2: New driver for QUSB2 PHY on Qcom chips")
Reviewed-by: Vivek Gautam <vivek.gautam@xxxxxxxxxxxxxx>
Reviewed-by: Evan Green <evgreen@xxxxxxxxxxxx>
Cc: stable <stable@xxxxxxxxxxxxxxx> # 4.14+
Signed-off-by: Manu Gautam <mgautam@xxxxxxxxxxxxxx>
---
drivers/phy/qualcomm/phy-qcom-qusb2.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/phy/qualcomm/phy-qcom-qusb2.c b/drivers/phy/qualcomm/phy-qcom-qusb2.c
index 94afeac..40fdef8 100644
--- a/drivers/phy/qualcomm/phy-qcom-qusb2.c
+++ b/drivers/phy/qualcomm/phy-qcom-qusb2.c
@@ -315,6 +315,10 @@ static void qusb2_phy_set_tune2_param(struct qusb2_phy *qphy)
const struct qusb2_phy_cfg *cfg = qphy->cfg;
u8 *val;

+ /* efuse register is optional */
+ if (!qphy->cell)
+ return;
+
/*
* Read efuse register having TUNE2/1 parameter's high nibble.
* If efuse register shows value as 0x0, or if we fail to find
--
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