[3/5] xhci: prepare for operation w/o shared hcd

Commit Message

Heiner Kallweit March 4, 2022, 6:35 p.m. UTC

This patch prepares xhci for the following scenario:
- If either of the root hubs has no ports, then omit shared hcd
- Main hcd can be USB3 if there are no USB2 ports

Signed-off-by: Heiner Kallweit <[e-mail]>
---
 drivers/usb/host/xhci-hub.c |  3 ++-
 drivers/usb/host/xhci-mem.c |  4 +++-
 drivers/usb/host/xhci.c     | 44 +++++++++++++++++++++++--------------
 drivers/usb/host/xhci.h     | 20 +++++++++++++++++
 4 files changed, 53 insertions(+), 18 deletions(-)

Patch

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index df3522dab..7931c7612 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -707,6 +707,7 @@  static int xhci_enter_test_mode(struct xhci_hcd *xhci,
 				u16 test_mode, u16 wIndex, unsigned long *flags)
 	__must_hold(&xhci->lock)
 {
+	struct usb_hcd *usb3_hcd = xhci_get_usb3_hcd(xhci);
 	int i, retval;
 
 	/* Disable all Device Slots */
@@ -727,7 +728,7 @@  static int xhci_enter_test_mode(struct xhci_hcd *xhci,
 	xhci_dbg(xhci, "Disable all port (PP = 0)\n");
 	/* Power off USB3 ports*/
 	for (i = 0; i < xhci->usb3_rhub.num_ports; i++)
-		xhci_set_port_power(xhci, xhci->shared_hcd, i, false, flags);
+		xhci_set_port_power(xhci, usb3_hcd, i, false, flags);
 	/* Power off USB2 ports*/
 	for (i = 0; i < xhci->usb2_rhub.num_ports; i++)
 		xhci_set_port_power(xhci, xhci->main_hcd, i, false, flags);
diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index f8c2b6c79..a1a17713a 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1072,7 +1072,7 @@  static u32 xhci_find_real_port_number(struct xhci_hcd *xhci,
 	struct usb_hcd *hcd;
 
 	if (udev->speed >= USB_SPEED_SUPER)
-		hcd = xhci->shared_hcd;
+		hcd = xhci_get_usb3_hcd(xhci);
 	else
 		hcd = xhci->main_hcd;
 
@@ -2362,6 +2362,8 @@  static int xhci_setup_port_arrays(struct xhci_hcd *xhci, gfp_t flags)
 		xhci->usb2_rhub.num_ports = USB_MAXCHILDREN;
 	}
 
+	xhci->needs_shared_hcd = 1;
+
 	/*
 	 * Note we could have all USB 3.0 ports, or all USB 2.0 ports.
 	 * Not sure how the USB core will handle a hub with no ports...
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 824b833ae..83a54a566 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -485,6 +485,10 @@  static void compliance_mode_recovery(struct timer_list *t)
 
 	xhci = from_timer(xhci, t, comp_mode_recovery_timer);
 	rhub = &xhci->usb3_rhub;
+	hcd = rhub->hcd;
+
+	if (!hcd)
+		return;
 
 	for (i = 0; i < rhub->num_ports; i++) {
 		temp = readl(rhub->ports[i]->addr);
@@ -498,7 +502,6 @@  static void compliance_mode_recovery(struct timer_list *t)
 					i + 1);
 			xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
 					"Attempting compliance mode recovery");
-			hcd = xhci->shared_hcd;
 
 			if (hcd->state == HC_STATE_SUSPENDED)
 				usb_hcd_resume_root_hub(hcd);
@@ -611,14 +614,11 @@  static int xhci_run_finished(struct xhci_hcd *xhci)
 		xhci_halt(xhci);
 		return -ENODEV;
 	}
-	xhci->shared_hcd->state = HC_STATE_RUNNING;
 	xhci->cmd_ring_state = CMD_RING_STATE_RUNNING;
 
 	if (xhci->quirks & XHCI_NEC_HOST)
 		xhci_ring_cmd_db(xhci);
 
-	xhci_dbg_trace(xhci, trace_xhci_dbg_init,
-			"Finished xhci_run for USB3 roothub");
 	return 0;
 }
 
@@ -693,12 +693,15 @@  int xhci_run(struct usb_hcd *hcd)
 			xhci_free_command(xhci, command);
 	}
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init,
-			"Finished xhci_run for USB2 roothub");
+			"Finished %s for main hcd", __func__);
 
 	xhci_create_dbc_dev(xhci);
 
 	xhci_debugfs_init(xhci);
 
+	if (!xhci->needs_shared_hcd)
+		return xhci_run_finished(xhci);
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(xhci_run);
@@ -980,7 +983,7 @@  int xhci_suspend(struct xhci_hcd *xhci, bool do_wakeup)
 		return 0;
 
 	if (hcd->state != HC_STATE_SUSPENDED ||
-			xhci->shared_hcd->state != HC_STATE_SUSPENDED)
+	    (xhci->shared_hcd && xhci->shared_hcd->state != HC_STATE_SUSPENDED))
 		return -EINVAL;
 
 	/* Clear root port wake on bits if wakeup not allowed. */
@@ -997,15 +1000,18 @@  int xhci_suspend(struct xhci_hcd *xhci, bool do_wakeup)
 		 __func__, hcd->self.busnum);
 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
 	del_timer_sync(&hcd->rh_timer);
-	clear_bit(HCD_FLAG_POLL_RH, &xhci->shared_hcd->flags);
-	del_timer_sync(&xhci->shared_hcd->rh_timer);
+	if (xhci->shared_hcd) {
+		clear_bit(HCD_FLAG_POLL_RH, &xhci->shared_hcd->flags);
+		del_timer_sync(&xhci->shared_hcd->rh_timer);
+	}
 
 	if (xhci->quirks & XHCI_SUSPEND_DELAY)
 		usleep_range(1000, 1500);
 
 	spin_lock_irq(&xhci->lock);
 	clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
-	clear_bit(HCD_FLAG_HW_ACCESSIBLE, &xhci->shared_hcd->flags);
+	if (xhci->shared_hcd)
+		clear_bit(HCD_FLAG_HW_ACCESSIBLE, &xhci->shared_hcd->flags);
 	/* step 1: stop endpoint */
 	/* skipped assuming that port suspend has done */
 
@@ -1105,7 +1111,8 @@  int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
 		msleep(100);
 
 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
-	set_bit(HCD_FLAG_HW_ACCESSIBLE, &xhci->shared_hcd->flags);
+	if (xhci->shared_hcd)
+		set_bit(HCD_FLAG_HW_ACCESSIBLE, &xhci->shared_hcd->flags);
 
 	spin_lock_irq(&xhci->lock);
 
@@ -1165,7 +1172,8 @@  int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
 
 		/* Let the USB core know _both_ roothubs lost power. */
 		usb_root_hub_lost_power(xhci->main_hcd->self.root_hub);
-		usb_root_hub_lost_power(xhci->shared_hcd->self.root_hub);
+		if (xhci->shared_hcd)
+			usb_root_hub_lost_power(xhci->shared_hcd->self.root_hub);
 
 		xhci_dbg(xhci, "Stop HCD\n");
 		xhci_halt(xhci);
@@ -1205,12 +1213,13 @@  int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
 
 		xhci_dbg(xhci, "Start the primary HCD\n");
 		retval = xhci_run(hcd->primary_hcd);
-		if (!retval) {
+		if (!retval && secondary_hcd) {
 			xhci_dbg(xhci, "Start the secondary HCD\n");
 			retval = xhci_run(secondary_hcd);
 		}
 		hcd->state = HC_STATE_SUSPENDED;
-		xhci->shared_hcd->state = HC_STATE_SUSPENDED;
+		if (xhci->shared_hcd)
+			xhci->shared_hcd->state = HC_STATE_SUSPENDED;
 		goto done;
 	}
 
@@ -1248,7 +1257,8 @@  int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
 		}
 
 		if (pending_portevent) {
-			usb_hcd_resume_root_hub(xhci->shared_hcd);
+			if (xhci->shared_hcd)
+				usb_hcd_resume_root_hub(xhci->shared_hcd);
 			usb_hcd_resume_root_hub(hcd);
 		}
 	}
@@ -1267,8 +1277,10 @@  int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
 	/* Re-enable port polling. */
 	xhci_dbg(xhci, "%s: starting usb%d port polling.\n",
 		 __func__, hcd->self.busnum);
-	set_bit(HCD_FLAG_POLL_RH, &xhci->shared_hcd->flags);
-	usb_hcd_poll_rh_status(xhci->shared_hcd);
+	if (xhci->shared_hcd) {
+		set_bit(HCD_FLAG_POLL_RH, &xhci->shared_hcd->flags);
+		usb_hcd_poll_rh_status(xhci->shared_hcd);
+	}
 	set_bit(HCD_FLAG_POLL_RH, &hcd->flags);
 	usb_hcd_poll_rh_status(hcd);
 
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 8a0026ee9..2edc910d9 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1908,6 +1908,8 @@  struct xhci_hcd {
 	unsigned		hw_lpm_support:1;
 	/* Broken Suspend flag for SNPS Suspend resume issue */
 	unsigned		broken_suspend:1;
+	/* Indicates that a shared hcd is needed */
+	unsigned		needs_shared_hcd:1;
 	/* cached usb2 extened protocol capabilites */
 	u32                     *ext_caps;
 	unsigned int            num_ext_caps;
@@ -1963,6 +1965,24 @@  static inline struct usb_hcd *xhci_to_hcd(struct xhci_hcd *xhci)
 	return xhci->main_hcd;
 }
 
+static inline struct usb_hcd *xhci_get_usb3_hcd(struct xhci_hcd *xhci)
+{
+	if (xhci->shared_hcd)
+		return xhci->shared_hcd;
+
+	if (!xhci->usb2_rhub.num_ports)
+		return xhci->main_hcd;
+
+	return NULL;
+}
+
+static inline bool xhci_hcd_is_usb3(struct usb_hcd *hcd)
+{
+	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+
+	return hcd == xhci_get_usb3_hcd(xhci);
+}
+
 #define xhci_dbg(xhci, fmt, args...) \
 	dev_dbg(xhci_to_hcd(xhci)->self.controller , fmt , ## args)
 #define xhci_err(xhci, fmt, args...) \