[PATCH v32 04/32] usb: host: xhci-mem: Allow for interrupter clients to choose specific index

Wesley Cheng
2025-01-08T01:22:44Z

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 | 24 ++++++++++++++----------
drivers/usb/host/xhci-sideband.c | 5 +++--
drivers/usb/host/xhci.h | 2 +-
include/linux/usb/xhci-sideband.h | 2 +-
4 files changed, 19 insertions(+), 14 deletions(-)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index a9129f5e3dce..2f6e1ed4c678 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -2332,14 +2332,15 @@ 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, unsigned int intr_num)
{
struct xhci_hcd *xhci = hcd_to_xhci(hcd);
struct xhci_interrupter *ir;
unsigned int i;
int err = -ENOSPC;

- if (!xhci->interrupters || xhci->max_interrupters <= 1)
+ if (!xhci->interrupters || xhci->max_interrupters <= 1 ||
+ intr_num >= xhci->max_interrupters)
return NULL;

ir = xhci_alloc_interrupter(xhci, segs, GFP_KERNEL);
@@ -2347,15 +2348,18 @@ 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) {
+ /* Find available secondary interrupter, interrupter 0 is reserved for primary */
+ for (i = 1; i < xhci->max_interrupters; i++) {
+ if (!xhci->interrupters[i]) {
+ err = xhci_add_interrupter(xhci, ir, i);
+ break;
+ }
}
+ } else {
+ if (!xhci->interrupters[intr_num])
+ err = xhci_add_interrupter(xhci, ir, intr_num);
}
-
spin_unlock_irq(&xhci->lock);

if (err) {
@@ -2371,7 +2375,7 @@ xhci_create_secondary_interrupter(struct usb_hcd *hcd, unsigned int segs,
i, imod_interval);

xhci_dbg(xhci, "Add secondary interrupter %d, max interrupters %d\n",
- i, xhci->max_interrupters);
+ ir->intr_num, xhci->max_interrupters);

return ir;
}
diff --git a/drivers/usb/host/xhci-sideband.c b/drivers/usb/host/xhci-sideband.c
index 711ee32a6411..6b58d29f57cd 100644
--- a/drivers/usb/host/xhci-sideband.c
+++ b/drivers/usb/host/xhci-sideband.c
@@ -259,7 +259,7 @@ 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;

@@ -273,7 +273,8 @@ 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 2a1e3f31f462..452c89f1b184 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1844,7 +1844,7 @@ 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, unsigned 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 0f92335517ab..7ec23e6e27d0 100644
--- a/include/linux/usb/xhci-sideband.h
+++ b/include/linux/usb/xhci-sideband.h
@@ -65,7 +65,7 @@ struct sg_table *
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);
int