[PATCH v22 06/38] usb: host: xhci-mem: Allow for interrupter clients to choose specific index

[Wesley Cheng <quic_wcheng@quicinc.com>]

Some clients may operate only on a specific XHCI interrupter instance.
Allow for the associated class driver to request for the interrupter that
it requires.

Signed-off-by: Wesley Cheng <quic_wcheng@quicinc.com>
---
 drivers/usb/host/xhci-mem.c       | 29 ++++++++++++++++-------------
 drivers/usb/host/xhci-sideband.c  |  4 ++--
 drivers/usb/host/xhci.h           |  2 +-
 include/linux/usb/xhci-sideband.h |  2 +-
 4 files changed, 20 insertions(+), 17 deletions(-)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 60dfc59260d8..997e8f27acb8 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -2340,7 +2340,7 @@ xhci_add_interrupter(struct xhci_hcd *xhci, struct xhci_interrupter *ir,
 
 struct xhci_interrupter *
 xhci_create_secondary_interrupter(struct usb_hcd *hcd, unsigned int segs,
-					u32 imod_interval)
+					u32 imod_interval, int intr_num)
 {
 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
 	struct xhci_interrupter *ir;
@@ -2355,29 +2355,32 @@ xhci_create_secondary_interrupter(struct usb_hcd *hcd, unsigned int segs,
 		return NULL;
 
 	spin_lock_irq(&xhci->lock);
-
 	/* Find available secondary interrupter, interrupter 0 is reserved for primary */
 	for (i = 1; i < xhci->max_interrupters; i++) {
-		if (xhci->interrupters[i] == NULL) {
-			err = xhci_add_interrupter(xhci, ir, i);
-			break;
+		if ((intr_num > 0 && i == intr_num) || intr_num <= 0) {
+			if (xhci->interrupters[i] == NULL) {
+				err = xhci_add_interrupter(xhci, ir, i);
+				if (err) {
+					spin_unlock_irq(&xhci->lock);
+					goto free_ir;
+				}
+				break;
+			}
 		}
 	}
-
 	spin_unlock_irq(&xhci->lock);
 
-	if (err) {
-		xhci_warn(xhci, "Failed to add secondary interrupter, max interrupters %d\n",
-			  xhci->max_interrupters);
-		xhci_free_interrupter(xhci, ir);
-		return NULL;
-	}
-
 	xhci_set_interrupter_moderation(ir, imod_interval);
+
 	xhci_dbg(xhci, "Add secondary interrupter %d, max interrupters %d\n",
 		 i, xhci->max_interrupters);
 
 	return ir;
+
+free_ir:
+	xhci_free_interrupter(xhci, ir);
+
+	return NULL;
 }
 EXPORT_SYMBOL_GPL(xhci_create_secondary_interrupter);
 
diff --git a/drivers/usb/host/xhci-sideband.c b/drivers/usb/host/xhci-sideband.c
index 7e7b15ec0cc7..690a08c8ed7f 100644
--- a/drivers/usb/host/xhci-sideband.c
+++ b/drivers/usb/host/xhci-sideband.c
@@ -254,7 +254,7 @@ EXPORT_SYMBOL_GPL(xhci_sideband_get_event_buffer);
  */
 int
 xhci_sideband_create_interrupter(struct xhci_sideband *sb, int num_seg,
-				 bool ip_autoclear, u32 imod_interval)
+				 bool ip_autoclear, u32 imod_interval, int intr_num)
 {
 	int ret = 0;
 
@@ -268,7 +268,7 @@ xhci_sideband_create_interrupter(struct xhci_sideband *sb, int num_seg,
 	}
 
 	sb->ir = xhci_create_secondary_interrupter(xhci_to_hcd(sb->xhci),
-			num_seg, imod_interval);
+			num_seg, imod_interval, intr_num);
 	if (!sb->ir) {
 		ret = -ENOMEM;
 		goto out;
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 35e5079ce621..bf50b56fef14 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1833,7 +1833,7 @@ void xhci_free_container_ctx(struct xhci_hcd *xhci,
 		struct xhci_container_ctx *ctx);
 struct xhci_interrupter *
 xhci_create_secondary_interrupter(struct usb_hcd *hcd, unsigned int segs,
-					u32 imod_interval);
+					u32 imod_interval, int intr_num);
 void xhci_remove_secondary_interrupter(struct usb_hcd
 				       *hcd, struct xhci_interrupter *ir);
 void xhci_skip_sec_intr_events(struct xhci_hcd *xhci,
diff --git a/include/linux/usb/xhci-sideband.h b/include/linux/usb/xhci-sideband.h
index 5fc95dd499aa..1231821b2947 100644
--- a/include/linux/usb/xhci-sideband.h
+++ b/include/linux/usb/xhci-sideband.h
@@ -56,7 +56,7 @@ xhci_sideband_get_event_buffer(struct xhci_sideband *sb);
 
 int
 xhci_sideband_create_interrupter(struct xhci_sideband *sb, int num_seg,
-				 bool ip_autoclear, u32 imod_interval);
+				 bool ip_autoclear, u32 imod_interval, int intr_num);
 
 void
 xhci_sideband_remove_interrupter(struct xhci_sideband *sb);