usb: dwc2: gadget: LPM flow fix

Added functionality to exit from L1 state by device initiation
using remote wakeup signaling, in case when function driver queuing
request while core in L1 state.

Fixes: 273d576c4d41 ("usb: dwc2: gadget: Add functionality to exit from LPM L1 state")
Fixes: 88b02f2cb1e1 ("usb: dwc2: Add core state checking")
CC: stable@vger.kernel.org
Signed-off-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Link: https://lore.kernel.org/r/b4d9de5382375dddbf7ef6049d9a82066ad87d5d.1710166393.git.Minas.Harutyunyan@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
index 5568448a977b1fd00b3a63d48bf57100c664295e..a141f83aba0ccefed100e62332cbd5c7134fbe63 100644 (file)
--- a/drivers/usb/dwc2/core.h
+++ b/drivers/usb/dwc2/core.h
@@ -1336,6 +1336,7 @@ int dwc2_backup_global_registers(struct dwc2_hsotg *hsotg);
 int dwc2_restore_global_registers(struct dwc2_hsotg *hsotg);
 
 void dwc2_enable_acg(struct dwc2_hsotg *hsotg);
+void dwc2_wakeup_from_lpm_l1(struct dwc2_hsotg *hsotg, bool remotewakeup);
 
 /* This function should be called on every hardware interrupt. */
 irqreturn_t dwc2_handle_common_intr(int irq, void *dev);

diff --git a/drivers/usb/dwc2/core_intr.c b/drivers/usb/dwc2/core_intr.c
index f8426e3d2b19bc9742e46f66b7c7c9bd6af33a69..26d752a4c3ca956c7f7bd7c5dbb4a38f6670b03d 100644 (file)
--- a/drivers/usb/dwc2/core_intr.c
+++ b/drivers/usb/dwc2/core_intr.c
@@ -323,10 +323,11 @@ static void dwc2_handle_session_req_intr(struct dwc2_hsotg *hsotg)
  * @hsotg: Programming view of DWC_otg controller
  *
  */
-static void dwc2_wakeup_from_lpm_l1(struct dwc2_hsotg *hsotg)
+void dwc2_wakeup_from_lpm_l1(struct dwc2_hsotg *hsotg, bool remotewakeup)
 {
        u32 glpmcfg;
-       u32 i = 0;
+       u32 pcgctl;
+       u32 dctl;
 
        if (hsotg->lx_state != DWC2_L1) {
                dev_err(hsotg->dev, "Core isn't in DWC2_L1 state\n");
@@ -335,37 +336,57 @@ static void dwc2_wakeup_from_lpm_l1(struct dwc2_hsotg *hsotg)
 
        glpmcfg = dwc2_readl(hsotg, GLPMCFG);
        if (dwc2_is_device_mode(hsotg)) {
-               dev_dbg(hsotg->dev, "Exit from L1 state\n");
+               dev_dbg(hsotg->dev, "Exit from L1 state, remotewakeup=%d\n", remotewakeup);
                glpmcfg &= ~GLPMCFG_ENBLSLPM;
-               glpmcfg &= ~GLPMCFG_HIRD_THRES_EN;
+               glpmcfg &= ~GLPMCFG_HIRD_THRES_MASK;
                dwc2_writel(hsotg, glpmcfg, GLPMCFG);
 
-               do {
-                       glpmcfg = dwc2_readl(hsotg, GLPMCFG);
+               pcgctl = dwc2_readl(hsotg, PCGCTL);
+               pcgctl &= ~PCGCTL_ENBL_SLEEP_GATING;
+               dwc2_writel(hsotg, pcgctl, PCGCTL);
 
-                       if (!(glpmcfg & (GLPMCFG_COREL1RES_MASK |
-                                        GLPMCFG_L1RESUMEOK | GLPMCFG_SLPSTS)))
-                               break;
+               glpmcfg = dwc2_readl(hsotg, GLPMCFG);
+               if (glpmcfg & GLPMCFG_ENBESL) {
+                       glpmcfg |= GLPMCFG_RSTRSLPSTS;
+                       dwc2_writel(hsotg, glpmcfg, GLPMCFG);
+               }
+
+               if (remotewakeup) {
+                       if (dwc2_hsotg_wait_bit_set(hsotg, GLPMCFG, GLPMCFG_L1RESUMEOK, 1000)) {
+                               dev_warn(hsotg->dev, "%s: timeout GLPMCFG_L1RESUMEOK\n", __func__);
+                               goto fail;
+                               return;
+                       }
+
+                       dctl = dwc2_readl(hsotg, DCTL);
+                       dctl |= DCTL_RMTWKUPSIG;
+                       dwc2_writel(hsotg, dctl, DCTL);
 
-                       udelay(1);
-               } while (++i < 200);
+                       if (dwc2_hsotg_wait_bit_set(hsotg, GINTSTS, GINTSTS_WKUPINT, 1000)) {
+                               dev_warn(hsotg->dev, "%s: timeout GINTSTS_WKUPINT\n", __func__);
+                               goto fail;
+                               return;
+                       }
+               }
 
-               if (i == 200) {
-                       dev_err(hsotg->dev, "Failed to exit L1 sleep state in 200us.\n");
+               glpmcfg = dwc2_readl(hsotg, GLPMCFG);
+               if (glpmcfg & GLPMCFG_COREL1RES_MASK || glpmcfg & GLPMCFG_SLPSTS ||
+                   glpmcfg & GLPMCFG_L1RESUMEOK) {
+                       goto fail;
                        return;
                }
-               dwc2_gadget_init_lpm(hsotg);
+
+               /* Inform gadget to exit from L1 */
+               call_gadget(hsotg, resume);
+               /* Change to L0 state */
+               hsotg->lx_state = DWC2_L0;
+               hsotg->bus_suspended = false;
+fail:          dwc2_gadget_init_lpm(hsotg);
        } else {
                /* TODO */
                dev_err(hsotg->dev, "Host side LPM is not supported.\n");
                return;
        }
-
-       /* Change to L0 state */
-       hsotg->lx_state = DWC2_L0;
-
-       /* Inform gadget to exit from L1 */
-       call_gadget(hsotg, resume);
 }
 
 /*
@@ -386,7 +407,7 @@ static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg)
        dev_dbg(hsotg->dev, "%s lxstate = %d\n", __func__, hsotg->lx_state);
 
        if (hsotg->lx_state == DWC2_L1) {
-               dwc2_wakeup_from_lpm_l1(hsotg);
+               dwc2_wakeup_from_lpm_l1(hsotg, false);
                return;
        }
 

diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index 8d3d937c81f9edfa7b17a7c1b29003f5ecb07e25..b2f6da5b65ccd0190fb2a9f789b4a9352c53a15e 100644 (file)
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -1415,6 +1415,10 @@ static int dwc2_hsotg_ep_queue(struct usb_ep *ep, struct usb_request *req,
                ep->name, req, req->length, req->buf, req->no_interrupt,
                req->zero, req->short_not_ok);
 
+       if (hs->lx_state == DWC2_L1) {
+               dwc2_wakeup_from_lpm_l1(hs, true);
+       }
+
        /* Prevent new request submission when controller is suspended */
        if (hs->lx_state != DWC2_L0) {
                dev_dbg(hs->dev, "%s: submit request only in active state\n",