xref: /linux/arch/powerpc/sysdev/rtc_cmos_setup.c (revision 93ab471889c6662b42ce7da257f31f24c08d7d9e)
1*93ab4718SWade Farnsworth /*
2*93ab4718SWade Farnsworth  * Setup code for PC-style Real-Time Clock.
3*93ab4718SWade Farnsworth  *
4*93ab4718SWade Farnsworth  * Author: Wade Farnsworth <wfarnsworth@mvista.com>
5*93ab4718SWade Farnsworth  *
6*93ab4718SWade Farnsworth  * 2007 (c) MontaVista Software, Inc. This file is licensed under
7*93ab4718SWade Farnsworth  * the terms of the GNU General Public License version 2. This program
8*93ab4718SWade Farnsworth  * is licensed "as is" without any warranty of any kind, whether express
9*93ab4718SWade Farnsworth  * or implied.
10*93ab4718SWade Farnsworth  */
11*93ab4718SWade Farnsworth 
12*93ab4718SWade Farnsworth #include <linux/platform_device.h>
13*93ab4718SWade Farnsworth #include <linux/err.h>
14*93ab4718SWade Farnsworth #include <linux/init.h>
15*93ab4718SWade Farnsworth #include <linux/mc146818rtc.h>
16*93ab4718SWade Farnsworth 
17*93ab4718SWade Farnsworth #include <asm/prom.h>
18*93ab4718SWade Farnsworth 
19*93ab4718SWade Farnsworth static int  __init add_rtc(void)
20*93ab4718SWade Farnsworth {
21*93ab4718SWade Farnsworth 	struct device_node *np;
22*93ab4718SWade Farnsworth 	struct platform_device *pd;
23*93ab4718SWade Farnsworth 	struct resource res;
24*93ab4718SWade Farnsworth 	int ret;
25*93ab4718SWade Farnsworth 
26*93ab4718SWade Farnsworth 	np = of_find_compatible_node(NULL, NULL, "pnpPNP,b00");
27*93ab4718SWade Farnsworth 	if (!np)
28*93ab4718SWade Farnsworth 		return -ENODEV;
29*93ab4718SWade Farnsworth 
30*93ab4718SWade Farnsworth 	ret = of_address_to_resource(np, 0, &res);
31*93ab4718SWade Farnsworth 	of_node_put(np);
32*93ab4718SWade Farnsworth 	if (ret)
33*93ab4718SWade Farnsworth 		return ret;
34*93ab4718SWade Farnsworth 
35*93ab4718SWade Farnsworth 	/*
36*93ab4718SWade Farnsworth 	 * RTC_PORT(x) is hardcoded in asm/mc146818rtc.h.  Verify that the
37*93ab4718SWade Farnsworth 	 * address provided by the device node matches.
38*93ab4718SWade Farnsworth 	 */
39*93ab4718SWade Farnsworth 	if (res.start != RTC_PORT(0))
40*93ab4718SWade Farnsworth 		return -EINVAL;
41*93ab4718SWade Farnsworth 
42*93ab4718SWade Farnsworth 	pd = platform_device_register_simple("rtc_cmos", -1,
43*93ab4718SWade Farnsworth 					     &res, 1);
44*93ab4718SWade Farnsworth 	if (IS_ERR(pd))
45*93ab4718SWade Farnsworth 		return PTR_ERR(pd);
46*93ab4718SWade Farnsworth 
47*93ab4718SWade Farnsworth 	return 0;
48*93ab4718SWade Farnsworth }
49*93ab4718SWade Farnsworth fs_initcall(add_rtc);
50