release/src-rt-6.x.4708/linux/linux-2.6.36/arch/sh/boards/mach-highlander/psw.c

   1 /*
   2  * arch/sh/boards/renesas/r7780rp/psw.c
   3  *
   4  * push switch support for RDBRP-1/RDBREVRP-1 debug boards.
   5  *
   6  * Copyright (C) 2006  Paul Mundt
   7  *
   8  * This file is subject to the terms and conditions of the GNU General Public
   9  * License.  See the file "COPYING" in the main directory of this archive
  10  * for more details.
  11  */
  12 #include <linux/io.h>
  13 #include <linux/init.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/platform_device.h>
  16 #include <mach/highlander.h>
  17 #include <asm/push-switch.h>
  18
  19 static irqreturn_t psw_irq_handler(int irq, void *arg)
  20 {
  21         struct platform_device *pdev = arg;
  22         struct push_switch *psw = platform_get_drvdata(pdev);
  23         struct push_switch_platform_info *psw_info = pdev->dev.platform_data;
  24         unsigned int l, mask;
  25         int ret = 0;
  26
  27         l = __raw_readw(PA_DBSW);
  28
  29         /* Nothing to do if there's no state change */
  30         if (psw->state) {
  31                 ret = 1;
  32                 goto out;
  33         }
  34
  35         mask = l & 0x70;
  36         /* Figure out who raised it */
  37         if (mask & (1 << psw_info->bit)) {
  38                 psw->state = !!(mask & (1 << psw_info->bit));
  39                 if (psw->state) /* debounce */
  40                         mod_timer(&psw->debounce, jiffies + 50);
  41
  42                 ret = 1;
  43         }
  44
  45 out:
  46         /* Clear the switch IRQs */
  47         l |= (0x7 << 12);
  48         __raw_writew(l, PA_DBSW);
  49
  50         return IRQ_RETVAL(ret);
  51 }
  52
  53 static struct resource psw_resources[] = {
  54         [0] = {
  55                 .start  = IRQ_PSW,
  56                 .flags  = IORESOURCE_IRQ,
  57         },
  58 };
  59
  60 static struct push_switch_platform_info s2_platform_data = {
  61         .name           = "s2",
  62         .bit            = 6,
  63         .irq_flags      = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
  64                           IRQF_SHARED,
  65         .irq_handler    = psw_irq_handler,
  66 };
  67
  68 static struct platform_device s2_switch_device = {
  69         .name           = "push-switch",
  70         .id             = 0,
  71         .num_resources  = ARRAY_SIZE(psw_resources),
  72         .resource       = psw_resources,
  73         .dev            = {
  74                 .platform_data = &s2_platform_data,
  75         },
  76 };
  77
  78 static struct push_switch_platform_info s3_platform_data = {
  79         .name           = "s3",
  80         .bit            = 5,
  81         .irq_flags      = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
  82                           IRQF_SHARED,
  83         .irq_handler    = psw_irq_handler,
  84 };
  85
  86 static struct platform_device s3_switch_device = {
  87         .name           = "push-switch",
  88         .id             = 1,
  89         .num_resources  = ARRAY_SIZE(psw_resources),
  90         .resource       = psw_resources,
  91         .dev            = {
  92                 .platform_data = &s3_platform_data,
  93         },
  94 };
  95
  96 static struct push_switch_platform_info s4_platform_data = {
  97         .name           = "s4",
  98         .bit            = 4,
  99         .irq_flags      = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
 100                           IRQF_SHARED,
 101         .irq_handler    = psw_irq_handler,
 102 };
 103
 104 static struct platform_device s4_switch_device = {
 105         .name           = "push-switch",
 106         .id             = 2,
 107         .num_resources  = ARRAY_SIZE(psw_resources),
 108         .resource       = psw_resources,
 109         .dev            = {
 110                 .platform_data = &s4_platform_data,
 111         },
 112 };
 113
 114 static struct platform_device *psw_devices[] = {
 115         &s2_switch_device, &s3_switch_device, &s4_switch_device,
 116 };
 117
 118 static int __init psw_init(void)
 119 {
 120         return platform_add_devices(psw_devices, ARRAY_SIZE(psw_devices));
 121 }
 122 module_init(psw_init);