From b107b904a6b856a62433c0baf3b160f22d9d8b19 Mon Sep 17 00:00:00 2001
From: Ian Lepore <ian@FreeBSD.org>
Date: Sun, 18 Feb 2018 02:01:41 +0000
Subject: [PATCH] Add a detach method so that this can be a kldunload-friendly
 module.

---
 sys/arm/freescale/imx/imx_i2c.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/sys/arm/freescale/imx/imx_i2c.c b/sys/arm/freescale/imx/imx_i2c.c
index 3b6d4aadb227..dfbe267dac19 100644
--- a/sys/arm/freescale/imx/imx_i2c.c
+++ b/sys/arm/freescale/imx/imx_i2c.c
@@ -154,6 +154,7 @@ struct i2c_softc {
 static phandle_t i2c_get_node(device_t, device_t);
 static int i2c_probe(device_t);
 static int i2c_attach(device_t);
+static int i2c_detach(device_t);
 
 static int i2c_repeated_start(device_t, u_char, int);
 static int i2c_start(device_t, u_char, int);
@@ -165,6 +166,7 @@ static int i2c_write(device_t, const char *, int, int *, int);
 static device_method_t i2c_methods[] = {
 	DEVMETHOD(device_probe,			i2c_probe),
 	DEVMETHOD(device_attach,		i2c_attach),
+	DEVMETHOD(device_detach,		i2c_detach),
 
 	/* OFW methods */
 	DEVMETHOD(ofw_bus_get_node,		i2c_get_node),
@@ -448,6 +450,28 @@ i2c_attach(device_t dev)
 	return (0);
 }
 
+static int
+i2c_detach(device_t dev)
+{
+	struct i2c_softc *sc;
+	int error;
+
+	sc = device_get_softc(dev);
+
+	if ((error = bus_generic_detach(sc->dev)) != 0) {
+		device_printf(sc->dev, "cannot detach child devices\n");
+		return (error);
+	}
+
+	if (sc->iicbus != NULL)
+		device_delete_child(dev, sc->iicbus);
+
+	if (sc->res != NULL)
+		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->res);
+
+	return (0);
+}
+
 static int
 i2c_repeated_start(device_t dev, u_char slave, int timeout)
 {