arch/powerpc/sysdev/rtc_cmos_setup.c

   1 /*
   2  * Setup code for PC-style Real-Time Clock.
   3  *
   4  * Author: Wade Farnsworth <wfarnsworth@mvista.com>
   5  *
   6  * 2007 (c) MontaVista Software, Inc. This file is licensed under
   7  * the terms of the GNU General Public License version 2. This program
   8  * is licensed "as is" without any warranty of any kind, whether express
   9  * or implied.
  10  */
  11
  12 #include <linux/platform_device.h>
  13 #include <linux/err.h>
  14 #include <linux/init.h>
  15 #include <linux/mc146818rtc.h>
  16
  17 #include <asm/prom.h>
  18
  19 static int  __init add_rtc(void)
  20 {
  21         struct device_node *np;
  22         struct platform_device *pd;
  23         struct resource res[2];
  24         unsigned int num_res = 1;
  25         int ret;
  26
  27         memset(&res, 0, sizeof(res));
  28
  29         np = of_find_compatible_node(NULL, NULL, "pnpPNP,b00");
  30         if (!np)
  31                 return -ENODEV;
  32
  33         ret = of_address_to_resource(np, 0, &res[0]);
  34         of_node_put(np);
  35         if (ret)
  36                 return ret;
  37
  38         /*
  39          * RTC_PORT(x) is hardcoded in asm/mc146818rtc.h.  Verify that the
  40          * address provided by the device node matches.
  41          */
  42         if (res[0].start != RTC_PORT(0))
  43                 return -EINVAL;
  44
  45         np = of_find_compatible_node(NULL, NULL, "chrp,iic");
  46         if (!np)
  47                 np = of_find_compatible_node(NULL, NULL, "pnpPNP,000");
  48         if (np) {
  49                 of_node_put(np);
  50                 /*
  51                  * Use a fixed interrupt value of 8 since on PPC if we are
  52                  * using this its off an i8259 which we ensure has interrupt
  53                  * numbers 0..15.
  54                  */
  55                 res[1].start = 8;
  56                 res[1].end = 8;
  57                 res[1].flags = IORESOURCE_IRQ;
  58                 num_res++;
  59         }
  60
  61         pd = platform_device_register_simple("rtc_cmos", -1,
  62                                              &res[0], num_res);
  63
  64         if (IS_ERR(pd))
  65                 return PTR_ERR(pd);
  66
  67         return 0;
  68 }
  69 fs_initcall(add_rtc);
  70
  71 MODULE_LICENSE("GPL");