git: a2bd4cd7863c - stable/13 - bus_if: Add a default implementation of get_property

The branch stable/13 has been updated by mw:

URL: https://cgit.FreeBSD.org/src/commit/?id=a2bd4cd7863c2fefe4e91443b84f63468d7138c0

commit a2bd4cd7863c2fefe4e91443b84f63468d7138c0
Author:     Kornel Duleba <mindal@semihalf.com>
AuthorDate: 2022-01-25 10:10:55 +0000
Commit:     Marcin Wojtas <mw@FreeBSD.org>
CommitDate: 2022-03-29 22:24:28 +0000

    bus_if: Add a default implementation of get_property
    
    There are multiple buses that pretend to be ofw compatible,
    e.g ofw_pci, mii_fdt. We now need to provide an implementation
    of BUS_GET_PROPERTY for every one of them. Instead of modifying
    them one by one it's better to just provide a default
    implementation that simply traverses up the device tree.
    Remove the now unneeded BUS_GET_PROPERTY implementation in mii_fdt.
    
    Reviewed by: andrew, bz
    Obtained from: Semihalf
    MFC after: 1 week
    Differential Revision: https://reviews.freebsd.org/D34031
    
    (cherry picked from commit 206dc82bc3fc5e1d90200e189ce5f2240dfec874)
---
 sys/dev/mii/mii_fdt.c | 15 ---------------
 sys/kern/bus_if.m     |  9 +--------
 sys/kern/subr_bus.c   | 17 +++++++++++++++++
 sys/sys/bus.h         |  3 +++
 4 files changed, 21 insertions(+), 23 deletions(-)

diff --git a/sys/dev/mii/mii_fdt.c b/sys/dev/mii/mii_fdt.c
index 387b02f69504..9cf3fd2fab37 100644
--- a/sys/dev/mii/mii_fdt.c
+++ b/sys/dev/mii/mii_fdt.c
@@ -326,20 +326,6 @@ miibus_fdt_get_devinfo(device_t bus, device_t child)
 	return (&ma->obd);
 }
 
-static ssize_t
-miibus_fdt_get_property(device_t bus, device_t child, const char *propname,
-    void *buf, size_t size)
-{
-	struct mii_attach_args *ma;
-
-	ma = device_get_ivars(child);
-
-	if (ma->obd.obd_node == 0)
-		return (-1);
-
-	return (OF_getencprop(ma->obd.obd_node, propname, buf, size));
-}
-
 static device_method_t miibus_fdt_methods[] = {
 	DEVMETHOD(device_probe,		miibus_fdt_probe),
 	DEVMETHOD(device_attach,	miibus_fdt_attach),
@@ -362,7 +348,6 @@ static device_method_t miibus_fdt_methods[] = {
 	DEVMETHOD(bus_get_resource,		bus_generic_rl_get_resource),
 	DEVMETHOD(bus_set_resource,		bus_generic_rl_set_resource),
 	DEVMETHOD(bus_get_resource_list,	miibus_fdt_get_resource_list),
-	DEVMETHOD(bus_get_property,		miibus_fdt_get_property),
 
 	DEVMETHOD_END
 };
diff --git a/sys/kern/bus_if.m b/sys/kern/bus_if.m
index 463d3fe38872..5b6577b963ec 100644
--- a/sys/kern/bus_if.m
+++ b/sys/kern/bus_if.m
@@ -88,13 +88,6 @@ CODE {
 		*newstart = start;
 		return (0);
 	}
-
-	static ssize_t
-	null_get_property(device_t dev, device_t child, const char *propname,
-	    void *propvalue, size_t size)
-	{
-		return (-1);
-	}
 };
 
 /**
@@ -962,4 +955,4 @@ METHOD ssize_t get_property {
 	const char *_propname;
 	void *_propvalue;
 	size_t _size;
-} DEFAULT null_get_property;
+} DEFAULT bus_generic_get_property;
diff --git a/sys/kern/subr_bus.c b/sys/kern/subr_bus.c
index 3949e0b29220..0139eb31f976 100644
--- a/sys/kern/subr_bus.c
+++ b/sys/kern/subr_bus.c
@@ -4062,6 +4062,23 @@ bus_generic_write_ivar(device_t dev, device_t child, int index,
 	return (ENOENT);
 }
 
+/**
+ * @brief Helper function for implementing BUS_GET_PROPERTY().
+ *
+ * This simply calls the BUS_GET_PROPERTY of the parent of dev,
+ * until a non-default implementation is found.
+ */
+ssize_t
+bus_generic_get_property(device_t dev, device_t child, const char *propname,
+    void *propvalue, size_t size)
+{
+	if (device_get_parent(dev) != NULL)
+		return (BUS_GET_PROPERTY(device_get_parent(dev), child,
+		    propname, propvalue, size));
+
+	return (-1);
+}
+
 /**
  * @brief Stub function for implementing BUS_GET_RESOURCE_LIST().
  *
diff --git a/sys/sys/bus.h b/sys/sys/bus.h
index 4c7d094c24b0..6500a283a7f5 100644
--- a/sys/sys/bus.h
+++ b/sys/sys/bus.h
@@ -441,6 +441,9 @@ bus_dma_tag_t
 bus_space_tag_t
 	bus_generic_get_bus_tag(device_t dev, device_t child);
 int	bus_generic_get_domain(device_t dev, device_t child, int *domain);
+ssize_t bus_generic_get_property(device_t dev, device_t child,
+				 const char *propname, void *propvalue,
+				 size_t size);
 struct resource_list *
 	bus_generic_get_resource_list (device_t, device_t);
 int	bus_generic_map_resource(device_t dev, device_t child, int type,