[PATCH 5.8 011/118] phy: omap-usb2-phy: disable PHY charger detect

Greg Kroah-Hartman
2020-09-21T16:44:31Z

From: Roger Quadros <rogerq@ti.com>

[ 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@ti.com>
Tested-by: Jan Kiszka <jan.kiszka@siemens.com>
Link: https://lore.kernel.org/r/20200824075127.14902-2-rogerq@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
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