/* $NetBSD: fdt_i2c.c,v 1.16 2025/09/23 00:52:14 thorpej Exp $ */ /* * Copyright (c) 2021, 2025 The NetBSD Foundation, Inc. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /*- * Copyright (c) 2015 Jared D. McNeill * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __KERNEL_RCSID(0, "$NetBSD: fdt_i2c.c,v 1.16 2025/09/23 00:52:14 thorpej Exp $"); #include #include #include #include #include #include #include #include #include #include struct fdtbus_i2c_controller { i2c_tag_t i2c_tag; int i2c_phandle; LIST_ENTRY(fdtbus_i2c_controller) i2c_next; }; static LIST_HEAD(, fdtbus_i2c_controller) fdtbus_i2c_controllers = LIST_HEAD_INITIALIZER(fdtbus_i2c_controllers); void fdtbus_register_i2c_controller(device_t dev, i2c_tag_t tag) { int phandle = devhandle_to_of(device_handle(dev)); struct fdtbus_i2c_controller *i2c; i2c = kmem_alloc(sizeof(*i2c), KM_SLEEP); i2c->i2c_tag = tag; i2c->i2c_phandle = phandle; LIST_INSERT_HEAD(&fdtbus_i2c_controllers, i2c, i2c_next); } static struct fdtbus_i2c_controller * fdtbus_get_i2c_controller(int phandle) { struct fdtbus_i2c_controller *i2c; LIST_FOREACH(i2c, &fdtbus_i2c_controllers, i2c_next) { if (i2c->i2c_phandle == phandle) return i2c; } return NULL; } i2c_tag_t fdtbus_i2c_get_tag(int phandle) { struct fdtbus_i2c_controller *i2c; i2c = fdtbus_get_i2c_controller(phandle); if (i2c == NULL) return NULL; return i2c->i2c_tag; } i2c_tag_t fdtbus_i2c_acquire(int phandle, const char *prop) { int i2c_phandle; i2c_phandle = fdtbus_get_phandle(phandle, prop); if (i2c_phandle == -1) return NULL; return fdtbus_i2c_get_tag(i2c_phandle); } static int fdtbus_i2c_enumerate_devices(device_t dev, devhandle_t call_handle, void *v) { struct i2c_enumerate_devices_args *args = v; int i2c_node, node; char name[32], compat_buf[32]; bus_addr_t addr; char *clist; int clist_size; bool cbrv; i2c_node = devhandle_to_of(call_handle); /* * The Device Tree bindings state that if a controller has a * child node named "i2c-bus", then that is the node beneath * which the child devices are populated. */ for (node = OF_child(i2c_node); node != 0; node = OF_peer(node)) { if (OF_getprop(node, "name", name, sizeof(name)) <= 0) { continue; } if (strcmp(name, "i2c-bus") == 0) { i2c_node = node; break; } } for (node = OF_child(i2c_node); node != 0; node = OF_peer(node)) { if (OF_getprop(node, "name", name, sizeof(name)) <= 0) { continue; } if (fdtbus_get_reg(node, 0, &addr, NULL) != 0) { continue; } clist_size = OF_getproplen(node, "compatible"); if (clist_size <= 0) { continue; } clist = kmem_tmpbuf_alloc(clist_size, compat_buf, sizeof(compat_buf), KM_SLEEP); if (OF_getprop(node, "compatible", clist, clist_size) < clist_size) { kmem_tmpbuf_free(clist, clist_size, compat_buf); continue; } cbrv = i2c_enumerate_device(dev, args, name, clist, clist_size, (i2c_addr_t)addr, devhandle_from_of(call_handle, node)); kmem_tmpbuf_free(clist, clist_size, compat_buf); if (!cbrv) { break; } } return 0; } OF_DEVICE_CALL_REGISTER(I2C_ENUMERATE_DEVICES_STR, fdtbus_i2c_enumerate_devices);