CVS commit: src/sys/dev/fdt

[Jason R Thorpe]

Module Name:    src
Committed By:   thorpej
Date:           Mon Dec 28 15:08:06 UTC 2020

Modified Files:
        src/sys/dev/fdt: i2cmux_fdt.c

Log Message:
The i2c-mux bindings specify that if the mux device has a child node named
"i2c-mux", then it is that node that is the parent of the i2c bus children.
This is to accommodate mux devices that may also have other kinds of child
nodes in addition to i2c bus child nodes.


To generate a diff of this commit:
cvs rdiff -u -r1.2 -r1.3 src/sys/dev/fdt/i2cmux_fdt.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.


Modified files:

Index: src/sys/dev/fdt/i2cmux_fdt.c
diff -u src/sys/dev/fdt/i2cmux_fdt.c:1.2 src/sys/dev/fdt/i2cmux_fdt.c:1.3
--- src/sys/dev/fdt/i2cmux_fdt.c:1.2	Wed Dec 23 16:04:42 2020
+++ src/sys/dev/fdt/i2cmux_fdt.c	Mon Dec 28 15:08:06 2020
@@ -1,4 +1,4 @@
-/*	$NetBSD: i2cmux_fdt.c,v 1.2 2020/12/23 16:04:42 thorpej Exp $	*/
+/*	$NetBSD: i2cmux_fdt.c,v 1.3 2020/12/28 15:08:06 thorpej Exp $	*/
 
 /*-
  * Copyright (c) 2020 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: i2cmux_fdt.c,v 1.2 2020/12/23 16:04:42 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: i2cmux_fdt.c,v 1.3 2020/12/28 15:08:06 thorpej Exp $");
 
 #include <sys/types.h>
 #include <sys/device.h>
@@ -94,6 +94,7 @@ struct iicmux_bus {
 struct iicmux_softc {
 	device_t			sc_dev;
 	int				sc_phandle;
+	int				sc_i2c_mux_phandle;
 	const struct iicmux_config *	sc_config;
 	i2c_tag_t			sc_i2c_parent;
 	struct iicmux_bus *		sc_busses;
@@ -317,10 +318,24 @@ static const struct of_compat_data compa
 static int
 iicmux_count_children(struct iicmux_softc * const sc)
 {
+	char name[32];
 	int child, count;
 
-	for (child = OF_child(sc->sc_phandle), count = 0; child;
+ restart:
+	for (child = OF_child(sc->sc_i2c_mux_phandle), count = 0; child;
 	     child = OF_peer(child)) {
+		if (OF_getprop(child, "name", name, sizeof(name)) <= 0) {
+			continue;
+		}
+		if (strcmp(name, "i2c-mux") == 0) {
+			/*
+			 * The node we encountered is the acutal parent
+			 * of the i2c bus children.  Stash its phandle
+			 * and restart the enumeration.
+			 */
+			sc->sc_i2c_mux_phandle = child;
+			goto restart;
+		}
 		count++;
 	}
 
@@ -394,6 +409,14 @@ iicmux_fdt_attach(device_t const parent,
 	aprint_naive("\n");
 	aprint_normal(": %s I2C mux\n", sc->sc_config->desc);
 
+	/*
+	 * We start out assuming that the i2c bus nodes are children of
+	 * our own node.  We'll adjust later if we encounter an "i2c-mux"
+	 * node when counting our children.  If we encounter such a node,
+	 * then it's that node that is the parent of the i2c bus children.
+	 */
+	sc->sc_i2c_mux_phandle = sc->sc_phandle;
+
 	sc->sc_i2c_parent = fdtbus_i2c_acquire(sc->sc_phandle, "i2c-parent");
 	if (sc->sc_i2c_parent == NULL) {
 		aprint_error_dev(sc->sc_dev, "unable to acquire i2c-parent\n");
@@ -409,7 +432,7 @@ iicmux_fdt_attach(device_t const parent,
 	    KM_SLEEP);
 
 	int child, idx;
-	for (child = OF_child(sc->sc_phandle), idx = 0; child;
+	for (child = OF_child(sc->sc_i2c_mux_phandle), idx = 0; child;
 	     child = OF_peer(child), idx++) {
 		KASSERT(idx < nchildren);
 		iicmux_attach_bus(sc, child, idx);