From 82d16c23518f9c3c275bf2557cd057b0e3f14ce1 Mon Sep 17 00:00:00 2001 From: Jonathan Bakker Date: Sat, 25 Apr 2020 10:36:33 -0700 Subject: phy: samsung: s5pv210-usb2: Add delay after reset [ Upstream commit 05942b8c36c7eb5d3fc5e375d4b0d0c49562e85d ] The USB phy takes some time to reset, so make sure we give it to it. The delay length was taken from the 4x12 phy driver. This manifested in issues with the DWC2 driver since commit fe369e1826b3 ("usb: dwc2: Make dwc2_readl/writel functions endianness-agnostic.") where the endianness check would read the DWC ID as 0 due to the phy still resetting, resulting in the wrong endian mode being chosen. Signed-off-by: Jonathan Bakker Link: https://lore.kernel.org/r/BN6PR04MB06605D52502816E500683553A3D10@BN6PR04MB0660.namprd04.prod.outlook.com Signed-off-by: Kishon Vijay Abraham I Signed-off-by: Sasha Levin --- drivers/phy/samsung/phy-s5pv210-usb2.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/phy/samsung/phy-s5pv210-usb2.c b/drivers/phy/samsung/phy-s5pv210-usb2.c index f6f72339bbc3..bb7fdf491c1c 100644 --- a/drivers/phy/samsung/phy-s5pv210-usb2.c +++ b/drivers/phy/samsung/phy-s5pv210-usb2.c @@ -142,6 +142,10 @@ static void s5pv210_phy_pwr(struct samsung_usb2_phy_instance *inst, bool on) udelay(10); rst &= ~rstbits; writel(rst, drv->reg_phy + S5PV210_UPHYRST); + /* The following delay is necessary for the reset sequence to be + * completed + */ + udelay(80); } else { pwr = readl(drv->reg_phy + S5PV210_UPHYPWR); pwr |= phypwr; -- cgit v1.2.3