Merge branch 'i2c/alert-for-acpi' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c material for 5.18 that is depended on by subsequent device
properties changes.

* 'i2c/alert-for-acpi' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: smbus: Use device_*() functions instead of of_*()
  docs: firmware-guide: ACPI: Add named interrupt doc
  device property: Add fwnode_irq_get_byname

Author: rafaeljw

Documentation/firmware-guide/acpi/enumeration.rst

@@ -143,6 +143,45 @@ In robust cases the client unfortunately needs to call
 acpi_dma_request_slave_chan_by_index() directly and therefore choose the
 specific FixedDMA resource by its index.
 
+Named Interrupts
+================
+
+Drivers enumerated via ACPI can have names to interrupts in the ACPI table
+which can be used to get the IRQ number in the driver.
+
+The interrupt name can be listed in _DSD as 'interrupt-names'. The names
+should be listed as an array of strings which will map to the Interrupt()
+resource in the ACPI table corresponding to its index.
+
+The table below shows an example of its usage::
+
+    Device (DEV0) {
+        ...
+        Name (_CRS, ResourceTemplate() {
+            ...
+            Interrupt (ResourceConsumer, Level, ActiveHigh, Exclusive) {
+                0x20,
+                0x24
+            }
+        })
+
+        Name (_DSD, Package () {
+            ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
+            Package () {
+                Package () {"interrupt-names",
+                Package (2) {"default", "alert"}},
+            }
+        ...
+        })
+    }
+
+The interrupt name 'default' will correspond to 0x20 in Interrupt()
+resource and 'alert' to 0x24. Note that only the Interrupt() resource
+is mapped and not GpioInt() or similar.
+
+The driver can call the function - fwnode_irq_get_byname() with the fwnode
+and interrupt name as arguments to get the corresponding IRQ number.
+
 SPI serial bus support
 ======================
 

drivers/base/property.c

@@ -935,6 +935,35 @@ void __iomem *fwnode_iomap(struct fwnode_handle *fwnode, int index)
 }
 EXPORT_SYMBOL(fwnode_iomap);
 
+/**
+ * fwnode_irq_get_byname - Get IRQ from a fwnode using its name
+ * @fwnode:	Pointer to the firmware node
+ * @name:	IRQ name
+ *
+ * Description:
+ * Find a match to the string @name in the 'interrupt-names' string array
+ * in _DSD for ACPI, or of_node for Device Tree. Then get the Linux IRQ
+ * number of the IRQ resource corresponding to the index of the matched
+ * string.
+ *
+ * Return:
+ * Linux IRQ number on success, or negative errno otherwise.
+ */
+int fwnode_irq_get_byname(const struct fwnode_handle *fwnode, const char *name)
+{
+	int index;
+
+	if (!name)
+		return -EINVAL;
+
+	index = fwnode_property_match_string(fwnode, "interrupt-names",  name);
+	if (index < 0)
+		return index;
+
+	return fwnode_irq_get(fwnode, index);
+}
+EXPORT_SYMBOL(fwnode_irq_get_byname);
+
 /**
  * fwnode_graph_get_next_endpoint - Get next endpoint firmware node
  * @fwnode: Pointer to the parent firmware node

drivers/i2c/i2c-core-base.c

@@ -1479,7 +1479,7 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
 		goto out_list;
 	}
 
-	res = of_i2c_setup_smbus_alert(adap);
+	res = i2c_setup_smbus_alert(adap);
 	if (res)
 		goto out_reg;
 

drivers/i2c/i2c-core-smbus.c

@@ -14,6 +14,7 @@
 #include <linux/err.h>
 #include <linux/i2c.h>
 #include <linux/i2c-smbus.h>
+#include <linux/property.h>
 #include <linux/slab.h>
 
 #include "i2c-core.h"
@@ -701,19 +702,19 @@ struct i2c_client *i2c_new_smbus_alert_device(struct i2c_adapter *adapter,
 }
 EXPORT_SYMBOL_GPL(i2c_new_smbus_alert_device);
 
-#if IS_ENABLED(CONFIG_I2C_SMBUS) && IS_ENABLED(CONFIG_OF)
-int of_i2c_setup_smbus_alert(struct i2c_adapter *adapter)
+#if IS_ENABLED(CONFIG_I2C_SMBUS)
+int i2c_setup_smbus_alert(struct i2c_adapter *adapter)
 {
 	int irq;
 
-	irq = of_property_match_string(adapter->dev.of_node, "interrupt-names",
-				       "smbus_alert");
+	irq = device_property_match_string(adapter->dev.parent, "interrupt-names",
+					   "smbus_alert");
 	if (irq == -EINVAL || irq == -ENODATA)
 		return 0;
 	else if (irq < 0)
 		return irq;
 
 	return PTR_ERR_OR_ZERO(i2c_new_smbus_alert_device(adapter, NULL));
 }
-EXPORT_SYMBOL_GPL(of_i2c_setup_smbus_alert);
+EXPORT_SYMBOL_GPL(i2c_setup_smbus_alert);
 #endif

drivers/i2c/i2c-smbus.c

@@ -13,7 +13,7 @@
 #include <linux/interrupt.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
-#include <linux/of_irq.h>
+#include <linux/property.h>
 #include <linux/slab.h>
 #include <linux/workqueue.h>
 
@@ -128,7 +128,8 @@ static int smbalert_probe(struct i2c_client *ara,
 	if (setup) {
 		irq = setup->irq;
 	} else {
-		irq = of_irq_get_byname(adapter->dev.of_node, "smbus_alert");
+		irq = fwnode_irq_get_byname(dev_fwnode(adapter->dev.parent),
+					    "smbus_alert");
 		if (irq <= 0)
 			return irq;
 	}

include/linux/i2c-smbus.h

@@ -30,10 +30,10 @@ struct i2c_client *i2c_new_smbus_alert_device(struct i2c_adapter *adapter,
 					      struct i2c_smbus_alert_setup *setup);
 int i2c_handle_smbus_alert(struct i2c_client *ara);
 
-#if IS_ENABLED(CONFIG_I2C_SMBUS) && IS_ENABLED(CONFIG_OF)
-int of_i2c_setup_smbus_alert(struct i2c_adapter *adap);
+#if IS_ENABLED(CONFIG_I2C_SMBUS)
+int i2c_setup_smbus_alert(struct i2c_adapter *adap);
 #else
-static inline int of_i2c_setup_smbus_alert(struct i2c_adapter *adap)
+static inline int i2c_setup_smbus_alert(struct i2c_adapter *adap)
 {
 	return 0;
 }

include/linux/property.h

@@ -121,6 +121,7 @@ struct fwnode_handle *fwnode_handle_get(struct fwnode_handle *fwnode);
 void fwnode_handle_put(struct fwnode_handle *fwnode);
 
 int fwnode_irq_get(const struct fwnode_handle *fwnode, unsigned int index);
+int fwnode_irq_get_byname(const struct fwnode_handle *fwnode, const char *name);
 
 void __iomem *fwnode_iomap(struct fwnode_handle *fwnode, int index);