@@ -43,6 +43,7 @@ int dwc2_backup_global_registers(struct dwc2_hsotg *hsotg)
/* Backup global regs */
gr = &hsotg->gr_backup;
+ gr->gintsts = dwc2_readl(hsotg, GINTSTS);
gr->gotgctl = dwc2_readl(hsotg, GOTGCTL);
gr->gintmsk = dwc2_readl(hsotg, GINTMSK);
gr->gahbcfg = dwc2_readl(hsotg, GAHBCFG);
@@ -667,6 +667,7 @@ struct dwc2_hw_params {
/**
* struct dwc2_gregs_backup - Holds global registers state before
* entering partial power down
+ * @gintsts: Backup of GINTSTS register
* @gotgctl: Backup of GOTGCTL register
* @gintmsk: Backup of GINTMSK register
* @gahbcfg: Backup of GAHBCFG register
@@ -683,6 +684,7 @@ struct dwc2_hw_params {
* @valid: True if registers values backuped.
*/
struct dwc2_gregs_backup {
+ u32 gintsts;
u32 gotgctl;
u32 gintmsk;
u32 gahbcfg;
@@ -685,6 +685,14 @@ static int __maybe_unused dwc2_suspend(struct device *dev)
regulator_disable(dwc2->usb33d);
}
+ if (is_device_mode)
+ ret = dwc2_gadget_backup_critical_registers(dwc2);
+ else
+ ret = dwc2_host_backup_critical_registers(dwc2);
+
+ if (ret)
+ return ret;
+
if (dwc2->ll_hw_enabled &&
(is_device_mode || dwc2_host_can_poweroff_phy(dwc2))) {
ret = __dwc2_lowlevel_hw_disable(dwc2);
@@ -694,6 +702,24 @@ static int __maybe_unused dwc2_suspend(struct device *dev)
return ret;
}
+static int dwc2_restore_critical_registers(struct dwc2_hsotg *hsotg)
+{
+ struct dwc2_gregs_backup *gr;
+
+ gr = &hsotg->gr_backup;
+
+ if (!gr->valid) {
+ dev_err(hsotg->dev, "No valid register backup, failed to restore\n");
+ return -EINVAL;
+ }
+
+ if (gr->gintsts & GINTSTS_CURMODE_HOST)
+ return dwc2_host_restore_critical_registers(hsotg);
+
+ return dwc2_gadget_restore_critical_registers(hsotg, DWC2_RESTORE_DCTL |
+ DWC2_RESTORE_DCFG);
+}
+
static int __maybe_unused dwc2_resume(struct device *dev)
{
struct dwc2_hsotg *dwc2 = dev_get_drvdata(dev);
@@ -706,6 +732,18 @@ static int __maybe_unused dwc2_resume(struct device *dev)
}
dwc2->phy_off_for_suspend = false;
+ /*
+ * During suspend it's possible that the power domain for the
+ * DWC2 controller is disabled and all register values get lost.
+ * In case the GUSBCFG register is not initialized, it's clear the
+ * registers must be restored.
+ */
+ if (!(dwc2_readl(dwc2, GUSBCFG) & GUSBCFG_TOUTCAL_MASK)) {
+ ret = dwc2_restore_critical_registers(dwc2);
+ if (ret)
+ return ret;
+ }
+
if (dwc2->params.activate_stm_id_vb_detection) {
unsigned long flags;
u32 ggpio, gotgctl;