phy: usb: Toggle the PHY power during init

When bringing up the PHY, it might be in a bad state if left powered.
One case is we lose the PLL lock if the PLL is gated while the PHY
is powered. Toggle the PHY power so we can start from a known state.

Fixes: 4e5b9c9a73b3 ("phy: usb: Add support for new Synopsys USB controller on the 7216")
Signed-off-by: Justin Chen <justin.chen@broadcom.com>
Acked-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://lore.kernel.org/r/20241024213540.1059412-1-justin.chen@broadcom.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/drivers/phy/broadcom/phy-brcm-usb-init-synopsys.c b/drivers/phy/broadcom/phy-brcm-usb-init-synopsys.c
index 950b7ae1d1a838874564390c9f7b85600b05e87e..dc452610934add4825e044d1141b9fbe1b79a97a 100644 (file)
--- a/drivers/phy/broadcom/phy-brcm-usb-init-synopsys.c
+++ b/drivers/phy/broadcom/phy-brcm-usb-init-synopsys.c
@@ -325,6 +325,12 @@ static void usb_init_common_7216(struct brcm_usb_init_params *params)
        void __iomem *ctrl = params->regs[BRCM_REGS_CTRL];
 
        USB_CTRL_UNSET(ctrl, USB_PM, XHC_S2_CLK_SWITCH_EN);
+
+       /*
+        * The PHY might be in a bad state if it is already powered
+        * up. Toggle the power just in case.
+        */
+       USB_CTRL_SET(ctrl, USB_PM, USB_PWRDN);
        USB_CTRL_UNSET(ctrl, USB_PM, USB_PWRDN);
 
        /* 1 millisecond - for USB clocks to settle down */