xref: /openbmc/linux/arch/powerpc/sysdev/of_rtc.c (revision bb3982b4)
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 static __initdata struct {
15 	const char *compatible;
16 	char *plat_name;
17 } of_rtc_table[] = {
18 	{ "ds1743-nvram", "rtc-ds1742" },
19 };
20 
21 void __init of_instantiate_rtc(void)
22 {
23 	struct device_node *node;
24 	int err;
25 	int i;
26 
27 	for (i = 0; i < ARRAY_SIZE(of_rtc_table); i++) {
28 		char *plat_name = of_rtc_table[i].plat_name;
29 
30 		for_each_compatible_node(node, NULL,
31 					 of_rtc_table[i].compatible) {
32 			struct resource *res;
33 
34 			res = kmalloc(sizeof(*res), GFP_KERNEL);
35 			if (!res) {
36 				printk(KERN_ERR "OF RTC: Out of memory "
37 				       "allocating resource structure for %pOF\n",
38 				       node);
39 				continue;
40 			}
41 
42 			err = of_address_to_resource(node, 0, res);
43 			if (err) {
44 				printk(KERN_ERR "OF RTC: Error "
45 				       "translating resources for %pOF\n",
46 				       node);
47 				continue;
48 			}
49 
50 			printk(KERN_INFO "OF_RTC: %pOF is a %s @ 0x%llx-0x%llx\n",
51 			       node, plat_name,
52 			       (unsigned long long)res->start,
53 			       (unsigned long long)res->end);
54 			platform_device_register_simple(plat_name, -1, res, 1);
55 		}
56 	}
57 }
58