diff options
Diffstat (limited to 'drivers/usb/dwc2/drd.c')
| -rw-r--r-- | drivers/usb/dwc2/drd.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/drivers/usb/dwc2/drd.c b/drivers/usb/dwc2/drd.c index 80eae88d76dd..99672360f34b 100644 --- a/drivers/usb/dwc2/drd.c +++ b/drivers/usb/dwc2/drd.c @@ -7,6 +7,7 @@ * Author(s): Amelie Delaunay <amelie.delaunay@st.com> */ +#include <linux/clk.h> #include <linux/iopoll.h> #include <linux/platform_device.h> #include <linux/usb/role.h> @@ -86,6 +87,20 @@ static int dwc2_drd_role_sw_set(struct usb_role_switch *sw, enum usb_role role) } #endif + /* + * In case of USB_DR_MODE_PERIPHERAL, clock is disabled at the end of + * the probe and enabled on udc_start. + * If role-switch set is called before the udc_start, we need to enable + * the clock to read/write GOTGCTL and GUSBCFG registers to override + * mode and sessions. It is the case if cable is plugged at boot. + */ + if (!hsotg->ll_hw_enabled && hsotg->clk) { + int ret = clk_prepare_enable(hsotg->clk); + + if (ret) + return ret; + } + spin_lock_irqsave(&hsotg->lock, flags); if (role == USB_ROLE_HOST) { @@ -110,6 +125,9 @@ static int dwc2_drd_role_sw_set(struct usb_role_switch *sw, enum usb_role role) /* This will raise a Connector ID Status Change Interrupt */ dwc2_force_mode(hsotg, role == USB_ROLE_HOST); + if (!hsotg->ll_hw_enabled && hsotg->clk) + clk_disable_unprepare(hsotg->clk); + dev_dbg(hsotg->dev, "%s-session valid\n", role == USB_ROLE_NONE ? "No" : role == USB_ROLE_HOST ? "A" : "B"); |