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, 54 insertions, 0 deletions

diff --git a/drivers/firmware/google/memconsole.c b/drivers/firmware/google/memconsole.c
new file mode 100644
index 000000000..6138a1653
--- /dev/null
+++ b/drivers/firmware/google/memconsole.c
@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * memconsole.c
+ *
+ * Architecture-independent parts of the memory based BIOS console.
+ *
+ * Copyright 2017 Google Inc.
+ */
+
+#include <linux/sysfs.h>
+#include <linux/kobject.h>
+#include <linux/module.h>
+
+#include "memconsole.h"
+
+static ssize_t memconsole_read(struct file *filp, struct kobject *kobp,
+			       const struct bin_attribute *bin_attr, char *buf,
+			       loff_t pos, size_t count)
+{
+	ssize_t (*memconsole_read_func)(char *, loff_t, size_t);
+
+	memconsole_read_func = bin_attr->private;
+	if (WARN_ON_ONCE(!memconsole_read_func))
+		return -EIO;
+
+	return memconsole_read_func(buf, pos, count);
+}
+
+static struct bin_attribute memconsole_bin_attr = {
+	.attr = {.name = "log", .mode = 0444},
+	.read = memconsole_read,
+};
+
+void memconsole_setup(ssize_t (*read_func)(char *, loff_t, size_t))
+{
+	memconsole_bin_attr.private = read_func;
+}
+EXPORT_SYMBOL(memconsole_setup);
+
+int memconsole_sysfs_init(void)
+{
+	return sysfs_create_bin_file(firmware_kobj, &memconsole_bin_attr);
+}
+EXPORT_SYMBOL(memconsole_sysfs_init);
+
+void memconsole_exit(void)
+{
+	sysfs_remove_bin_file(firmware_kobj, &memconsole_bin_attr);
+}
+EXPORT_SYMBOL(memconsole_exit);
+
+MODULE_AUTHOR("Google, Inc.");
+MODULE_DESCRIPTION("Architecture-independent parts of the memory based BIOS console");
+MODULE_LICENSE("GPL");