arch/powerpc/platforms/pasemi/electra_ide.c

   1 /*
   2  * Copyright (C) 2007 PA Semi, Inc
   3  *
   4  * Maintained by: Olof Johansson <olof@lixom.net>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  18  */
  19
  20 #include <linux/platform_device.h>
  21
  22 #include <asm/prom.h>
  23 #include <asm/system.h>
  24
  25 /* The electra IDE interface is incredibly simple: Just a device on the localbus
  26  * with interrupts hooked up to one of the GPIOs. The device tree contains the
  27  * address window and interrupt mappings already, and the pata_platform driver handles
  28  * the rest. We just need to hook the two up.
  29  */
  30
  31 #define MAX_IFS 4       /* really, we have only one */
  32
  33 static struct platform_device *pdevs[MAX_IFS];
  34
  35 static int __devinit electra_ide_init(void)
  36 {
  37         struct device_node *np;
  38         struct resource r[3];
  39         int ret = 0;
  40         int i;
  41
  42         np = of_find_compatible_node(NULL, "ide", "electra-ide");
  43         i = 0;
  44
  45         while (np && i < MAX_IFS) {
  46                 memset(r, 0, sizeof(r));
  47
  48                 /* pata_platform wants two address ranges: one for the base registers,
  49                  * another for the control (altstatus). It's located at offset 0x3f6 in
  50                  * the window, but the device tree only has one large register window
  51                  * that covers both ranges. So we need to split it up by hand here:
  52                  */
  53
  54                 ret = of_address_to_resource(np, 0, &r[0]);
  55                 if (ret)
  56                         goto out;
  57                 ret = of_address_to_resource(np, 0, &r[1]);
  58                 if (ret)
  59                         goto out;
  60
  61                 r[1].start += 0x3f6;
  62                 r[0].end = r[1].start-1;
  63
  64                 r[2].start = irq_of_parse_and_map(np, 0);
  65                 r[2].end = irq_of_parse_and_map(np, 0);
  66                 r[2].flags = IORESOURCE_IRQ;
  67
  68                 pr_debug("registering platform device at 0x%lx/0x%lx, irq is %ld\n",
  69                          r[0].start, r[1].start, r[2].start);
  70                 pdevs[i] = platform_device_register_simple("pata_platform", i, r, 3);
  71                 if (IS_ERR(pdevs[i])) {
  72                         ret = PTR_ERR(pdevs[i]);
  73                         pdevs[i] = NULL;
  74                         goto out;
  75                 }
  76                 np = of_find_compatible_node(np, "ide", "electra-ide");
  77         }
  78 out:
  79         return ret;
  80 }
  81 module_init(electra_ide_init);
  82
  83 static void __devexit electra_ide_exit(void)
  84 {
  85         int i;
  86
  87         for (i = 0; i < MAX_IFS; i++)
  88                 if (pdevs[i])
  89                         platform_device_unregister(pdevs[i]);
  90 }
  91 module_exit(electra_ide_exit);
  92
  93
  94 MODULE_LICENSE("GPL");
  95 MODULE_AUTHOR ("Olof Johansson <olof@lixom.net>");
  96 MODULE_DESCRIPTION("PA Semi Electra IDE driver");