Add OFW support to the in tree gpio compatible devices: gpioiic(4) and

gpioled(4).

Tested on RPi and BBB (using the hardware I2C controller and gpioiic(4) for
the I2C tests).  It was also verified for regressions on RSPRO (MIPS/ar71xx)
used as reference for a non OFW-based system.

Update the gpioled(4) and gpioiic(4) man pages with some details and
examples about the FDT/OFW support.

Some compatibility details pointed out by imp@ will follow in subsequent
commits.

Approved by:	adrian (mentor, implicit)

1 files changed, 40 insertions, 0 deletions

diff --git a/sys/dev/gpio/gpioiic.c b/sys/dev/gpio/gpioiic.c
index 37af21c..d7772b6 100644
--- a/sys/dev/gpio/gpioiic.c
+++ b/sys/dev/gpio/gpioiic.c
@@ -28,6 +28,8 @@
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
+#include "opt_platform.h"
+
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/bus.h>
@@ -38,6 +40,12 @@ __FBSDID("$FreeBSD$");
 #include <sys/gpio.h>
 #include "gpiobus_if.h"
 
+#ifdef FDT
+#include <dev/ofw/ofw_bus.h>
+#include <dev/ofw/ofw_bus_subr.h>
+#include <dev/fdt/fdt_common.h>
+#endif
+
 #include <dev/iicbus/iiconf.h>
 #include <dev/iicbus/iicbus.h>
 
@@ -71,6 +79,10 @@ static int
 gpioiic_probe(device_t dev)
 {
 
+#ifdef FDT
+	if (!ofw_bus_is_compatible(dev, "gpioiic"))
+		return (ENXIO);
+#endif
 	device_set_desc(dev, "GPIO I2C bit-banging driver");
 
 	return (0);
@@ -81,6 +93,10 @@ gpioiic_attach(device_t dev)
 {
 	struct gpioiic_softc	*sc = device_get_softc(dev);
 	device_t		bitbang;
+#ifdef FDT
+	phandle_t		node;
+	pcell_t			pin;
+#endif
 
 	sc->sc_dev = dev;
 	sc->sc_busdev = device_get_parent(dev);
@@ -91,6 +107,15 @@ gpioiic_attach(device_t dev)
 		device_get_unit(dev), "sda", &sc->sda_pin))
 		sc->sda_pin = SDA_PIN_DEFAULT;
 
+#ifdef FDT
+	if ((node = ofw_bus_get_node(dev)) == -1)
+		return (ENXIO);
+	if (OF_getencprop(node, "scl", &pin, sizeof(pin)) > 0)
+		sc->scl_pin = (int)pin;
+	if (OF_getencprop(node, "sda", &pin, sizeof(pin)) > 0)
+		sc->sda_pin = (int)pin;
+#endif
+
 	/* add generic bit-banging code */
 	bitbang = device_add_child(dev, "iicbb", -1);
 	device_probe_and_attach(bitbang);
@@ -209,6 +234,16 @@ gpioiic_reset(device_t dev, u_char speed, u_char addr, u_char *oldaddr)
 	return (IIC_ENOADDR);
 }
 
+#ifdef FDT
+static phandle_t
+gpioiic_get_node(device_t bus, device_t dev)
+{
+
+	/* We only have one child, the iicbb, which needs our own node. */
+	return (ofw_bus_get_node(bus));
+}
+#endif
+
 static devclass_t gpioiic_devclass;
 
 static device_method_t gpioiic_methods[] = {
@@ -225,6 +260,11 @@ static device_method_t gpioiic_methods[] = {
 	DEVMETHOD(iicbb_getscl,		gpioiic_getscl),
 	DEVMETHOD(iicbb_reset,		gpioiic_reset),
 
+#ifdef FDT
+	/* OFW bus interface */
+	DEVMETHOD(ofw_bus_get_node,	gpioiic_get_node),
+#endif
+
 	{ 0, 0 }
 };