[PATCH 6.6 370/396] usb: dwc2: gadget: LPM flow fix

Greg Kroah-Hartman
2024-04-01T16:56:23Z

From: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>

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>
---
drivers/usb/dwc2/core.h | 1
drivers/usb/dwc2/core_intr.c | 65 ++++++++++++++++++++++++++++---------------
drivers/usb/dwc2/gadget.c | 4 ++
3 files changed, 48 insertions(+), 22 deletions(-)

--- a/drivers/usb/dwc2/core.h
+++ b/drivers/usb/dwc2/core.h
@@ -1336,6 +1336,7 @@ int dwc2_backup_global_registers(struct
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);
--- 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
* @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(stru

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);
-
- if (!(glpmcfg & (GLPMCFG_COREL1RES_MASK |
- GLPMCFG_L1RESUMEOK | GLPMCFG_SLPSTS)))
- break;
+ pcgctl = dwc2_readl(hsotg, PCGCTL);
+ pcgctl &= ~PCGCTL_ENBL_SLEEP_GATING;
+ dwc2_writel(hsotg, pcgctl, PCGCTL);
+
+ glpmcfg = dwc2_readl(hsotg, GLPMCFG);
+ if (glpmcfg & GLPMCFG_ENBESL) {
+ glpmcfg |= GLPMCFG_RSTRSLPSTS;
+ dwc2_writel(hsotg, glpmcfg, GLPMCFG);
+ }

- udelay(1);
- } while (++i < 200);
+ 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);
+
+ 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_
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;
}

--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -1415,6 +1415,10 @@ static int dwc2_hsotg_ep_queue(struct us
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",