Some use cases maybe require that the secondary interrupter's events to be handled by the OS. In this case, configure the IMOD and the skip_events property to enable the interrupter's events. By default, assume that the secondary interrupter doesn't want to enable OS event handling.
Signed-off-by: Wesley Cheng quic_wcheng@quicinc.com --- drivers/usb/host/xhci-sideband.c | 28 ++++++++++++++++++++++++++++ include/linux/usb/xhci-sideband.h | 2 ++ 2 files changed, 30 insertions(+)
diff --git a/drivers/usb/host/xhci-sideband.c b/drivers/usb/host/xhci-sideband.c index 0944bf31d772..504a6f1586b5 100644 --- a/drivers/usb/host/xhci-sideband.c +++ b/drivers/usb/host/xhci-sideband.c @@ -237,6 +237,30 @@ xhci_sideband_get_event_buffer(struct xhci_sideband *sb) } EXPORT_SYMBOL_GPL(xhci_sideband_get_event_buffer);
+/** + * xhci_sideband_enable_interrupt - enable interrupt for secondary interrupter + * @sb: sideband instance for this usb device + * @imod_interval: number of event ring segments to allocate + * + * Enables OS owned event handling for a particular interrupter if client + * requests for it. In addition, set the IMOD interval for this particular + * interrupter. + * + * Returns 0 on success, negative error otherwise + */ +int xhci_sideband_enable_interrupt(struct xhci_sideband *sb, u32 imod_interval) +{ + if (!sb || !sb->ir) + return -ENODEV; + + xhci_set_interrupter_moderation(sb->ir, imod_interval); + sb->ir->skip_events = false; + xhci_enable_interrupter(sb->ir); + + return 0; +} +EXPORT_SYMBOL_GPL(xhci_sideband_enable_interrupt); + /** * xhci_sideband_create_interrupter - creates a new interrupter for this sideband * @sb: sideband instance for this usb device @@ -275,6 +299,8 @@ xhci_sideband_create_interrupter(struct xhci_sideband *sb, int num_seg, }
sb->ir->ip_autoclear = ip_autoclear; + /* skip events for secondary interrupters by default */ + sb->ir->skip_events = true;
out: mutex_unlock(&sb->mutex); @@ -297,6 +323,8 @@ xhci_sideband_remove_interrupter(struct xhci_sideband *sb) return;
mutex_lock(&sb->mutex); + if (!sb->ir->skip_events) + xhci_disable_interrupter(sb->ir); xhci_remove_secondary_interrupter(xhci_to_hcd(sb->xhci), sb->ir);
sb->ir = NULL; diff --git a/include/linux/usb/xhci-sideband.h b/include/linux/usb/xhci-sideband.h index 1035dae43cee..a749ae307ba7 100644 --- a/include/linux/usb/xhci-sideband.h +++ b/include/linux/usb/xhci-sideband.h @@ -54,6 +54,8 @@ xhci_sideband_get_endpoint_buffer(struct xhci_sideband *sb, struct sg_table * xhci_sideband_get_event_buffer(struct xhci_sideband *sb);
+int xhci_sideband_enable_interrupt(struct xhci_sideband *sb, u32 imod_interval); + int xhci_sideband_create_interrupter(struct xhci_sideband *sb, int num_seg, bool ip_autoclear);