soundwire: bus: Make IRQ handling conditionally built

SoundWire has provisions for a simple callback for the IRQ handling so
has no hard dependency on IRQ_DOMAIN, but the recent addition of IRQ
handling was causing builds without IRQ_DOMAIN to fail. Resolve this by
moving the IRQ handling into its own file and only add it to the build
when IRQ_DOMAIN is included in the kernel.

Fixes: 12a95123bf ("soundwire: bus: Allow SoundWire peripherals to register IRQ handlers")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202309150522.MoKeF4jx-lkp@intel.com/
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20230920160401.854052-1-ckeepax@opensource.cirrus.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

drivers/soundwire/Makefile

@@ -15,6 +15,10 @@ ifdef CONFIG_DEBUG_FS
 soundwire-bus-y += debugfs.o
 endif
 
+ifdef CONFIG_IRQ_DOMAIN
+soundwire-bus-y += irq.o
+endif
+
 #AMD driver
 soundwire-amd-y :=	amd_manager.o
 obj-$(CONFIG_SOUNDWIRE_AMD) += soundwire-amd.o

drivers/soundwire/bus.c

@@ -3,13 +3,13 @@
 
 #include <linux/acpi.h>
 #include <linux/delay.h>
-#include <linux/irq.h>
 #include <linux/mod_devicetable.h>
 #include <linux/pm_runtime.h>
 #include <linux/soundwire/sdw_registers.h>
 #include <linux/soundwire/sdw.h>
 #include <linux/soundwire/sdw_type.h>
 #include "bus.h"
+#include "irq.h"
 #include "sysfs_local.h"
 
 static DEFINE_IDA(sdw_bus_ida);
@@ -25,23 +25,6 @@ static int sdw_get_id(struct sdw_bus *bus)
 	return 0;
 }
 
-static int sdw_irq_map(struct irq_domain *h, unsigned int virq,
-		       irq_hw_number_t hw)
-{
-	struct sdw_bus *bus = h->host_data;
-
-	irq_set_chip_data(virq, bus);
-	irq_set_chip(virq, &bus->irq_chip);
-	irq_set_nested_thread(virq, 1);
-	irq_set_noprobe(virq);
-
-	return 0;
-}
-
-static const struct irq_domain_ops sdw_domain_ops = {
-	.map	= sdw_irq_map,
-};
-
 /**
  * sdw_bus_master_add() - add a bus Master instance
  * @bus: bus instance
@@ -168,13 +151,9 @@ int sdw_bus_master_add(struct sdw_bus *bus, struct device *parent,
 	bus->params.curr_bank = SDW_BANK0;
 	bus->params.next_bank = SDW_BANK1;
 
-	bus->irq_chip.name = dev_name(bus->dev);
-	bus->domain = irq_domain_create_linear(fwnode, SDW_MAX_DEVICES,
-					       &sdw_domain_ops, bus);
-	if (!bus->domain) {
-		dev_err(bus->dev, "Failed to add IRQ domain\n");
-		return -EINVAL;
-	}
+	ret = sdw_irq_create(bus, fwnode);
+	if (ret)
+		return ret;
 
 	return 0;
 }
@@ -213,7 +192,7 @@ void sdw_bus_master_delete(struct sdw_bus *bus)
 {
 	device_for_each_child(bus->dev, NULL, sdw_delete_slave);
 
-	irq_domain_remove(bus->domain);
+	sdw_irq_delete(bus);
 
 	sdw_master_device_del(bus);
 

drivers/soundwire/bus_type.c

@@ -7,6 +7,7 @@
 #include <linux/soundwire/sdw.h>
 #include <linux/soundwire/sdw_type.h>
 #include "bus.h"
+#include "irq.h"
 #include "sysfs_local.h"
 
 /**
@@ -122,11 +123,8 @@ static int sdw_drv_probe(struct device *dev)
 	if (drv->ops && drv->ops->read_prop)
 		drv->ops->read_prop(slave);
 
-	if (slave->prop.use_domain_irq) {
-		slave->irq = irq_create_mapping(slave->bus->domain, slave->dev_num);
-		if (!slave->irq)
-			dev_warn(dev, "Failed to map IRQ\n");
-	}
+	if (slave->prop.use_domain_irq)
+		sdw_irq_create_mapping(slave);
 
 	/* init the sysfs as we have properties now */
 	ret = sdw_slave_sysfs_init(slave);
@@ -176,8 +174,7 @@ static int sdw_drv_remove(struct device *dev)
 	slave->probed = false;
 
 	if (slave->prop.use_domain_irq)
-		irq_dispose_mapping(irq_find_mapping(slave->bus->domain,
-						     slave->dev_num));
+		sdw_irq_dispose_mapping(slave);
 
 	mutex_unlock(&slave->sdw_dev_lock);
 

drivers/soundwire/irq.c

@@ -0,0 +1,59 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2023 Cirrus Logic, Inc. and
+//                    Cirrus Logic International Semiconductor Ltd.
+
+#include <linux/device.h>
+#include <linux/fwnode.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/soundwire/sdw.h>
+#include "irq.h"
+
+static int sdw_irq_map(struct irq_domain *h, unsigned int virq,
+		       irq_hw_number_t hw)
+{
+	struct sdw_bus *bus = h->host_data;
+
+	irq_set_chip_data(virq, bus);
+	irq_set_chip(virq, &bus->irq_chip);
+	irq_set_nested_thread(virq, 1);
+	irq_set_noprobe(virq);
+
+	return 0;
+}
+
+static const struct irq_domain_ops sdw_domain_ops = {
+	.map	= sdw_irq_map,
+};
+
+int sdw_irq_create(struct sdw_bus *bus,
+		   struct fwnode_handle *fwnode)
+{
+	bus->irq_chip.name = dev_name(bus->dev);
+
+	bus->domain = irq_domain_create_linear(fwnode, SDW_MAX_DEVICES,
+					       &sdw_domain_ops, bus);
+	if (!bus->domain) {
+		dev_err(bus->dev, "Failed to add IRQ domain\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+void sdw_irq_delete(struct sdw_bus *bus)
+{
+	irq_domain_remove(bus->domain);
+}
+
+void sdw_irq_create_mapping(struct sdw_slave *slave)
+{
+	slave->irq = irq_create_mapping(slave->bus->domain, slave->dev_num);
+	if (!slave->irq)
+		dev_warn(&slave->dev, "Failed to map IRQ\n");
+}
+
+void sdw_irq_dispose_mapping(struct sdw_slave *slave)
+{
+	irq_dispose_mapping(irq_find_mapping(slave->bus->domain, slave->dev_num));
+}

drivers/soundwire/irq.h

@@ -0,0 +1,43 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2023 Cirrus Logic, Inc. and
+ *                    Cirrus Logic International Semiconductor Ltd.
+ */
+
+#ifndef __SDW_IRQ_H
+#define __SDW_IRQ_H
+
+#include <linux/soundwire/sdw.h>
+#include <linux/fwnode.h>
+
+#if IS_ENABLED(CONFIG_IRQ_DOMAIN)
+
+int sdw_irq_create(struct sdw_bus *bus,
+		   struct fwnode_handle *fwnode);
+void sdw_irq_delete(struct sdw_bus *bus);
+void sdw_irq_create_mapping(struct sdw_slave *slave);
+void sdw_irq_dispose_mapping(struct sdw_slave *slave);
+
+#else /* CONFIG_IRQ_DOMAIN */
+
+static inline int sdw_irq_create(struct sdw_bus *bus,
+				 struct fwnode_handle *fwnode)
+{
+	return 0;
+}
+
+static inline void sdw_irq_delete(struct sdw_bus *bus)
+{
+}
+
+static inline void sdw_irq_create_mapping(struct sdw_slave *slave)
+{
+}
+
+static inline void sdw_irq_dispose_mapping(struct sdw_slave *slave)
+{
+}
+
+#endif /* CONFIG_IRQ_DOMAIN */
+
+#endif /* __SDW_IRQ_H */