[PATCH v3] phy: fsl-imx8mq-usb: Clear the PCS_TX_SWING_FULL field before using it

[Stefano Radaelli]

Clear the PCS_TX_SWING_FULL field mask before setting the new value
in PHY_CTRL5 register. Without clearing the mask first, the OR operation
could leave previously set bits, resulting in incorrect register
configuration.

Fixes: 63c85ad0cd81 ("phy: fsl-imx8mp-usb: add support for phy tuning")
Suggested-by: Leonid Segal <leonids@xxxxxxxxxxxxx>
Acked-by: Pierluigi Passaro <pierluigi.p@xxxxxxxxxxxxx>
Signed-off-by: Stefano Radaelli <stefano.r@xxxxxxxxxxxxx>
Reviewed-by: Xu Yang <xu.yang_2@xxxxxxx>
Reviewed-by: Frank Li <Frank.Li@xxxxxxx>
---
v3:
- Fixed commit message line wrapping (75 chars)
v2:
- Improved commit subject as suggested by Fabio Estevam

 drivers/phy/freescale/phy-fsl-imx8mq-usb.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
index ad8a55012e42..9458b6e5fcf4 100644
--- a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
+++ b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
@@ -504,6 +504,7 @@ static void imx8m_phy_tune(struct imx8mq_usb_phy *imx_phy)
 
 	if (imx_phy->pcs_tx_swing_full != PHY_TUNE_DEFAULT) {
 		value = readl(imx_phy->base + PHY_CTRL5);
+		value &= ~PHY_CTRL5_PCS_TX_SWING_FULL_MASK;
 		value |= FIELD_PREP(PHY_CTRL5_PCS_TX_SWING_FULL_MASK,
 				   imx_phy->pcs_tx_swing_full);
 		writel(value, imx_phy->base + PHY_CTRL5);

base-commit: ea1013c1539270e372fc99854bc6e4d94eaeff66
-- 
2.47.3