From: Saranya Gopal <saranya.gopal@xxxxxxxxx>
Enable static DRD mode in Intel platforms which guarantees
successful role switch all the time. This fixes issues like
software role switch failure after cold boot and issue with
role switch when USB 3.0 cable is used. But, do not enable
static DRD mode for Cherrytrail devices which rely on firmware
for role switch.
Signed-off-by: Saranya Gopal <saranya.gopal@xxxxxxxxx>
Signed-off-by: Balaji Manoharan <m.balaji@xxxxxxxxx>
Signed-off-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
---
.../usb/roles/intel-xhci-usb-role-switch.c | 26 ++++++++++++++++++-
1 file changed, 25 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/roles/intel-xhci-usb-role-switch.c b/drivers/usb/roles/intel-xhci-usb-role-switch.c
index 7325a84dd1c8..9101ff94c8d2 100644
--- a/drivers/usb/roles/intel-xhci-usb-role-switch.c
+++ b/drivers/usb/roles/intel-xhci-usb-role-switch.c
@@ -19,6 +19,7 @@
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
+#include <linux/property.h>
#include <linux/usb/role.h>
/* register definition */
@@ -26,6 +27,9 @@
#define SW_VBUS_VALID BIT(24)
#define SW_IDPIN_EN BIT(21)
#define SW_IDPIN BIT(20)
+#define SW_SWITCH_EN_CFG0 BIT(16)
+#define SW_DRD_STATIC_HOST_CFG0 1
+#define SW_DRD_STATIC_DEV_CFG0 2
#define DUAL_ROLE_CFG1 0x6c
#define HOST_MODE BIT(29)
@@ -37,6 +41,7 @@
struct intel_xhci_usb_data {
struct usb_role_switch *role_sw;
void __iomem *base;
+ bool disable_sw_switch;
};
static const struct software_node intel_xhci_usb_node = {
@@ -63,23 +68,39 @@ static int intel_xhci_usb_set_role(struct device *dev, enum usb_role role)
pm_runtime_get_sync(dev);
- /* Set idpin value as requested */
+ /*
+ * Set idpin value as requested.
+ * Since some devices rely on firmware setting DRD_CONFIG and
+ * SW_SWITCH_EN_CFG0 bits to be zero for role switch,
+ * do not set these bits for those devices.
+ */
val = readl(data->base + DUAL_ROLE_CFG0);
switch (role) {
case USB_ROLE_NONE:
val |= SW_IDPIN;
val &= ~SW_VBUS_VALID;
+ val &= ~(SW_DRD_STATIC_DEV_CFG0 | SW_DRD_STATIC_HOST_CFG0);
break;
case USB_ROLE_HOST:
val &= ~SW_IDPIN;
val &= ~SW_VBUS_VALID;
+ if (!data->disable_sw_switch) {
+ val &= ~SW_DRD_STATIC_DEV_CFG0;
+ val |= SW_DRD_STATIC_HOST_CFG0;
+ }
break;
case USB_ROLE_DEVICE:
val |= SW_IDPIN;
val |= SW_VBUS_VALID;
+ if (!data->disable_sw_switch) {
+ val &= ~SW_DRD_STATIC_HOST_CFG0;
+ val |= SW_DRD_STATIC_DEV_CFG0;
+ }
break;
}
val |= SW_IDPIN_EN;
+ if (!data->disable_sw_switch)
+ val |= SW_SWITCH_EN_CFG0;
writel(val, data->base + DUAL_ROLE_CFG0);
@@ -156,6 +177,9 @@ static int intel_xhci_usb_probe(struct platform_device *pdev)
sw_desc.allow_userspace_control = true,
sw_desc.fwnode = software_node_fwnode(&intel_xhci_usb_node);
+ data->disable_sw_switch = device_property_read_bool(dev,
+ "sw_switch_disable");
+
data->role_sw = usb_role_switch_register(dev, &sw_desc);
if (IS_ERR(data->role_sw)) {
fwnode_handle_put(sw_desc.fwnode);
--
2.23.0.rc1
