PCI: Add pci_irq_type() to query the allocated interrupt typegrafted

Add a helper that returns PCI_IRQ_MSIX, PCI_IRQ_MSI, or PCI_IRQ_INTX
based on the interrupt type the PCI core selected after
pci_alloc_irq_vectors().

Several drivers already open-code this check against pdev->msix_enabled
and pdev->msi_enabled, or even open code this helper [1].

A common helper avoids the duplication and keeps drivers from accessing
the bitfield directly (see also [2]).

Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: John Hubbard <jhubbard@nvidia.com>
Link: https://elixir.bootlin.com/linux/v7.1/source/drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c#L196 [1]
Inspired-by: John Hubbard <jhubbard@nvidia.com>
Link: https://lore.kernel.org/all/DKKG2QM3YJYB.Z2H2B2UXJ75N@kernel.org/ [2]
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260813165234.620555-5-dakr@kernel.org
[ Add missing pci_irq_type() stub for CONFIG_PCI=n. ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>

1 files changed, 48 insertions, 0 deletions

diff --git a/drivers/usb/common/led.c b/drivers/usb/common/led.c
new file mode 100644
index 000000000..1de18d90b
--- /dev/null
+++ b/drivers/usb/common/led.c
@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * LED Triggers for USB Activity
+ *
+ * Copyright 2014 Michal Sojka <sojka@merica.cz>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/leds.h>
+#include <linux/usb.h>
+#include "common.h"
+
+#define BLINK_DELAY 30
+
+DEFINE_LED_TRIGGER(ledtrig_usb_gadget);
+DEFINE_LED_TRIGGER(ledtrig_usb_host);
+
+void usb_led_activity(enum usb_led_event ev)
+{
+	struct led_trigger *trig = NULL;
+
+	switch (ev) {
+	case USB_LED_EVENT_GADGET:
+		trig = ledtrig_usb_gadget;
+		break;
+	case USB_LED_EVENT_HOST:
+		trig = ledtrig_usb_host;
+		break;
+	}
+	/* led_trigger_blink_oneshot() handles trig == NULL gracefully */
+	led_trigger_blink_oneshot(trig, BLINK_DELAY, BLINK_DELAY, 0);
+}
+EXPORT_SYMBOL_GPL(usb_led_activity);
+
+
+void __init ledtrig_usb_init(void)
+{
+	led_trigger_register_simple("usb-gadget", &ledtrig_usb_gadget);
+	led_trigger_register_simple("usb-host", &ledtrig_usb_host);
+}
+
+void __exit ledtrig_usb_exit(void)
+{
+	led_trigger_unregister_simple(ledtrig_usb_gadget);
+	led_trigger_unregister_simple(ledtrig_usb_host);
+}