[PATCH v28 01/33] xhci: support setting interrupt moderation IMOD for secondary interrupters

[Wesley Cheng]

From: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>

Allow creators of xHCI secondary interrupters to specify the interrupt
moderation interval value in nanoseconds when creating the interrupter.

If not sure what value to use then use the xhci driver default
xhci->imod_interval

Suggested-by: Wesley Cheng <quic_wcheng@xxxxxxxxxxx>
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240905143300.1959279-13-mathias.nyman@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/usb/host/xhci-mem.c | 8 +++++++-
 drivers/usb/host/xhci.c     | 4 ++--
 drivers/usb/host/xhci.h     | 5 ++++-
 3 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 3100219d6496..a25576f27e66 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -2334,7 +2334,8 @@ 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)
+xhci_create_secondary_interrupter(struct usb_hcd *hcd, unsigned int segs,
+				  u32 imod_interval)
 {
 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
 	struct xhci_interrupter *ir;
@@ -2367,6 +2368,11 @@ xhci_create_secondary_interrupter(struct usb_hcd *hcd, unsigned int segs)
 		return NULL;
 	}
 
+	err = xhci_set_interrupter_moderation(ir, imod_interval);
+	if (err)
+		xhci_warn(xhci, "Failed to set interrupter %d moderation to %uns\n",
+			  i, imod_interval);
+
 	xhci_dbg(xhci, "Add secondary interrupter %d, max interrupters %d\n",
 		 i, xhci->max_interrupters);
 
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 37eb37b0affa..ed1bb7ed44b0 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -347,8 +347,8 @@ static int xhci_disable_interrupter(struct xhci_interrupter *ir)
 }
 
 /* interrupt moderation interval imod_interval in nanoseconds */
-static int xhci_set_interrupter_moderation(struct xhci_interrupter *ir,
-					   u32 imod_interval)
+int xhci_set_interrupter_moderation(struct xhci_interrupter *ir,
+				    u32 imod_interval)
 {
 	u32 imod;
 
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 30415158ed3c..324644165d93 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1827,7 +1827,8 @@ struct xhci_container_ctx *xhci_alloc_container_ctx(struct xhci_hcd *xhci,
 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);
+xhci_create_secondary_interrupter(struct usb_hcd *hcd, unsigned int segs,
+				  u32 imod_interval);
 void xhci_remove_secondary_interrupter(struct usb_hcd
 				       *hcd, struct xhci_interrupter *ir);
 
@@ -1867,6 +1868,8 @@ int xhci_alloc_tt_info(struct xhci_hcd *xhci,
 		struct xhci_virt_device *virt_dev,
 		struct usb_device *hdev,
 		struct usb_tt *tt, gfp_t mem_flags);
+int xhci_set_interrupter_moderation(struct xhci_interrupter *ir,
+				    u32 imod_interval);
 
 /* xHCI ring, segment, TRB, and TD functions */
 dma_addr_t xhci_trb_virt_to_dma(struct xhci_segment *seg, union xhci_trb *trb);