usb: dwc2: gadget: LPM flow fix

commit 5d69a3b54e5a630c90d82a4c2bdce3d53dc78710 upstream.

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 a505e963ef60e9d62c82ea0c5bde5e3b6bdd5e20..cbf975b75df7c0cbfde2462e55339ad389346b7f 100644 (file)
--- a/drivers/usb/dwc2/core.h
+++ b/drivers/usb/dwc2/core.h
@@ -1358,6 +1358,7 @@ 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 2288cf86d230a4bcf22e1021aa2f006f1a93b630..5db14b1a5cb389824285f251087ed4cdfe6f0284 100644 (file)
--- a/drivers/usb/dwc2/core_intr.c
+++ b/drivers/usb/dwc2/core_intr.c
@@ -353,10 +353,11 @@ 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");
@@ -365,37 +366,57 @@ 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);
 }
 
 /*
@@ -416,7 +437,7 @@ 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 7cd33a7ff34f3d466e52b2e14338eb96b3af598d..f6b2a4f2e59d9098d46b18b6b8bf60ff62db6e8b 100644 (file)
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -1416,6 +1416,10 @@ 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",