1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Instantiate mmio-mapped RTC chips based on device tree information
4  *
5  * Copyright 2007 David Gibson <dwg@au1.ibm.com>, IBM Corporation.
6  */
7 #include <linux/kernel.h>
8 #include <linux/of.h>
9 #include <linux/init.h>
10 #include <linux/of_address.h>
11 #include <linux/of_platform.h>
12 #include <linux/slab.h>
13 
14 #include <asm/prom.h>
15 
16 static __initdata struct {
17 	const char *compatible;
18 	char *plat_name;
19 } of_rtc_table[] = {
20 	{ "ds1743-nvram", "rtc-ds1742" },
21 };
22 
of_instantiate_rtc(void)23 void __init of_instantiate_rtc(void)
24 {
25 	struct device_node *node;
26 	int err;
27 	int i;
28 
29 	for (i = 0; i < ARRAY_SIZE(of_rtc_table); i++) {
30 		char *plat_name = of_rtc_table[i].plat_name;
31 
32 		for_each_compatible_node(node, NULL,
33 					 of_rtc_table[i].compatible) {
34 			struct resource *res;
35 
36 			res = kmalloc(sizeof(*res), GFP_KERNEL);
37 			if (!res) {
38 				printk(KERN_ERR "OF RTC: Out of memory "
39 				       "allocating resource structure for %pOF\n",
40 				       node);
41 				continue;
42 			}
43 
44 			err = of_address_to_resource(node, 0, res);
45 			if (err) {
46 				printk(KERN_ERR "OF RTC: Error "
47 				       "translating resources for %pOF\n",
48 				       node);
49 				continue;
50 			}
51 
52 			printk(KERN_INFO "OF_RTC: %pOF is a %s @ 0x%llx-0x%llx\n",
53 			       node, plat_name,
54 			       (unsigned long long)res->start,
55 			       (unsigned long long)res->end);
56 			platform_device_register_simple(plat_name, -1, res, 1);
57 		}
58 	}
59 }
60