From: Roger Quadros <rogerq@xxxxxx> [ Upstream commit ad7a7acaedcf45071c822b6c983f9c1e084041c9 ] AM654x PG1.0 has a silicon bug that D+ is pulled high after POR, which could cause enumeration failure with some USB hubs. Disabling the USB2_PHY Charger Detect function will put D+ into the normal state. This addresses Silicon Errata: i2075 - "USB2PHY: USB2PHY Charger Detect is Enabled by Default Without VBUS Presence" Signed-off-by: Roger Quadros <rogerq@xxxxxx> Tested-by: Jan Kiszka <jan.kiszka@xxxxxxxxxxx> Link: https://lore.kernel.org/r/20200824075127.14902-2-rogerq@xxxxxx Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/phy/ti/phy-omap-usb2.c | 47 +++++++++++++++++++++++++++++----- 1 file changed, 40 insertions(+), 7 deletions(-) diff --git a/drivers/phy/ti/phy-omap-usb2.c b/drivers/phy/ti/phy-omap-usb2.c index cb2dd3230fa76..507f79d14adb8 100644 --- a/drivers/phy/ti/phy-omap-usb2.c +++ b/drivers/phy/ti/phy-omap-usb2.c @@ -22,10 +22,15 @@ #include <linux/mfd/syscon.h> #include <linux/regmap.h> #include <linux/of_platform.h> +#include <linux/sys_soc.h> #define USB2PHY_ANA_CONFIG1 0x4c #define USB2PHY_DISCON_BYP_LATCH BIT(31) +#define USB2PHY_CHRG_DET 0x14 +#define USB2PHY_CHRG_DET_USE_CHG_DET_REG BIT(29) +#define USB2PHY_CHRG_DET_DIS_CHG_DET BIT(28) + /* SoC Specific USB2_OTG register definitions */ #define AM654_USB2_OTG_PD BIT(8) #define AM654_USB2_VBUS_DET_EN BIT(5) @@ -43,6 +48,7 @@ #define OMAP_USB2_HAS_START_SRP BIT(0) #define OMAP_USB2_HAS_SET_VBUS BIT(1) #define OMAP_USB2_CALIBRATE_FALSE_DISCONNECT BIT(2) +#define OMAP_USB2_DISABLE_CHRG_DET BIT(3) struct omap_usb { struct usb_phy phy; @@ -236,6 +242,13 @@ static int omap_usb_init(struct phy *x) omap_usb_writel(phy->phy_base, USB2PHY_ANA_CONFIG1, val); } + if (phy->flags & OMAP_USB2_DISABLE_CHRG_DET) { + val = omap_usb_readl(phy->phy_base, USB2PHY_CHRG_DET); + val |= USB2PHY_CHRG_DET_USE_CHG_DET_REG | + USB2PHY_CHRG_DET_DIS_CHG_DET; + omap_usb_writel(phy->phy_base, USB2PHY_CHRG_DET, val); + } + return 0; } @@ -329,6 +342,26 @@ static const struct of_device_id omap_usb2_id_table[] = { }; MODULE_DEVICE_TABLE(of, omap_usb2_id_table); +static void omap_usb2_init_errata(struct omap_usb *phy) +{ + static const struct soc_device_attribute am65x_sr10_soc_devices[] = { + { .family = "AM65X", .revision = "SR1.0" }, + { /* sentinel */ } + }; + + /* + * Errata i2075: USB2PHY: USB2PHY Charger Detect is Enabled by + * Default Without VBUS Presence. + * + * AM654x SR1.0 has a silicon bug due to which D+ is pulled high after + * POR, which could cause enumeration failure with some USB hubs. + * Disabling the USB2_PHY Charger Detect function will put D+ + * into the normal state. + */ + if (soc_device_match(am65x_sr10_soc_devices)) + phy->flags |= OMAP_USB2_DISABLE_CHRG_DET; +} + static int omap_usb2_probe(struct platform_device *pdev) { struct omap_usb *phy; @@ -366,14 +399,14 @@ static int omap_usb2_probe(struct platform_device *pdev) phy->mask = phy_data->mask; phy->power_on = phy_data->power_on; phy->power_off = phy_data->power_off; + phy->flags = phy_data->flags; - if (phy_data->flags & OMAP_USB2_CALIBRATE_FALSE_DISCONNECT) { - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - phy->phy_base = devm_ioremap_resource(&pdev->dev, res); - if (IS_ERR(phy->phy_base)) - return PTR_ERR(phy->phy_base); - phy->flags |= OMAP_USB2_CALIBRATE_FALSE_DISCONNECT; - } + omap_usb2_init_errata(phy); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + phy->phy_base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(phy->phy_base)) + return PTR_ERR(phy->phy_base); phy->syscon_phy_power = syscon_regmap_lookup_by_phandle(node, "syscon-phy-power"); -- 2.25.1
