[PATCH v2 1/3] usb: dwc3: core: Host wake up support from system suspend

From: Sandeep Maheswaram
Date: Wed Jul 08 2020 - 15:17:18 EST


Avoiding phy powerdown in host mode so that it can be wake up by devices.
Added need_phy_for_wakeup flag to distinugush resume path and hs_phy_flags
to check connection status and set phy mode and configure interrupts.

Signed-off-by: Sandeep Maheswaram <sanm@xxxxxxxxxxxxxx>
---
drivers/usb/dwc3/core.c | 47 ++++++++++++++++++++++++++++++++++++++++-------
drivers/usb/dwc3/core.h | 2 ++
2 files changed, 42 insertions(+), 7 deletions(-)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 25c686a7..eb7c225 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -31,12 +31,14 @@
#include <linux/usb/gadget.h>
#include <linux/usb/of.h>
#include <linux/usb/otg.h>
+#include <linux/usb/hcd.h>

#include "core.h"
#include "gadget.h"
#include "io.h"

#include "debug.h"
+#include "../host/xhci.h"

#define DWC3_DEFAULT_AUTOSUSPEND_DELAY 5000 /* ms */

@@ -1627,10 +1629,36 @@ static int dwc3_core_init_for_resume(struct dwc3 *dwc)
return ret;
}

+static void dwc3_set_phy_speed_flags(struct dwc3 *dwc)
+{
+
+ int i, num_ports;
+ u32 reg;
+ struct usb_hcd *hcd = platform_get_drvdata(dwc->xhci);
+ struct xhci_hcd *xhci_hcd = hcd_to_xhci(hcd);
+
+ dwc->hs_phy_flags &= ~(PHY_MODE_USB_HOST_HS | PHY_MODE_USB_HOST_LS);
+
+ reg = readl(&xhci_hcd->cap_regs->hcs_params1);
+
+ num_ports = HCS_MAX_PORTS(reg);
+ for (i = 0; i < num_ports; i++) {
+ reg = readl(&xhci_hcd->op_regs->port_status_base + i * 0x04);
+ if (reg & PORT_PE) {
+ if (DEV_HIGHSPEED(reg) || DEV_FULLSPEED(reg))
+ dwc->hs_phy_flags |= PHY_MODE_USB_HOST_HS;
+ else if (DEV_LOWSPEED(reg))
+ dwc->hs_phy_flags |= PHY_MODE_USB_HOST_LS;
+ }
+ }
+ phy_set_mode(dwc->usb2_generic_phy, dwc->hs_phy_flags);
+}
+
static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
{
unsigned long flags;
u32 reg;
+ struct usb_hcd *hcd = platform_get_drvdata(dwc->xhci);

switch (dwc->current_dr_role) {
case DWC3_GCTL_PRTCAP_DEVICE:
@@ -1643,9 +1671,12 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
dwc3_core_exit(dwc);
break;
case DWC3_GCTL_PRTCAP_HOST:
+ dwc3_set_phy_speed_flags(dwc);
if (!PMSG_IS_AUTO(msg)) {
- dwc3_core_exit(dwc);
- break;
+ if (usb_wakeup_enabled_descendants(hcd->self.root_hub))
+ dwc->need_phy_for_wakeup = true;
+ else
+ dwc->need_phy_for_wakeup = false;
}

/* Let controller to suspend HSPHY before PHY driver suspends */
@@ -1705,11 +1736,13 @@ static int dwc3_resume_common(struct dwc3 *dwc, pm_message_t msg)
break;
case DWC3_GCTL_PRTCAP_HOST:
if (!PMSG_IS_AUTO(msg)) {
- ret = dwc3_core_init_for_resume(dwc);
- if (ret)
- return ret;
- dwc3_set_prtcap(dwc, DWC3_GCTL_PRTCAP_HOST);
- break;
+ if (!dwc->need_phy_for_wakeup) {
+ ret = dwc3_core_init_for_resume(dwc);
+ if (ret)
+ return ret;
+ dwc3_set_prtcap(dwc, DWC3_GCTL_PRTCAP_HOST);
+ break;
+ }
}
/* Restore GUSB2PHYCFG bits that were modified in suspend */
reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 013f42a..5367d510e 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -1094,6 +1094,8 @@ struct dwc3 {
struct phy *usb3_generic_phy;

bool phys_ready;
+ bool need_phy_for_wakeup;
+ unsigned int hs_phy_flags;

struct ulpi *ulpi;
bool ulpi_ready;
--
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