2 * Intel Merrifield watchdog platform device library file
4 * (C) Copyright 2014 Intel Corporation
5 * Author: David Cohen <david.a.cohen@linux.intel.com>
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; version 2
13 #include <linux/init.h>
14 #include <linux/interrupt.h>
15 #include <linux/platform_device.h>
16 #include <linux/platform_data/intel-mid_wdt.h>
18 #include <asm/intel-mid.h>
19 #include <asm/intel_scu_ipc.h>
20 #include <asm/io_apic.h>
21 #include <asm/hw_irq.h>
23 #define TANGIER_EXT_TIMER0_MSI 12
25 static struct platform_device wdt_dev = {
26 .name = "intel_mid_wdt",
30 static int tangier_probe(struct platform_device *pdev)
33 struct irq_alloc_info info;
34 struct intel_mid_wdt_pdata *pdata = pdev->dev.platform_data;
39 /* IOAPIC builds identity mapping between GSI and IRQ on MID */
41 ioapic_set_alloc_attr(&info, cpu_to_node(0), 1, 0);
42 if (mp_map_gsi_to_irq(gsi, IOAPIC_MAP_ALLOC, &info) <= 0) {
43 dev_warn(&pdev->dev, "cannot find interrupt %d in ioapic\n",
51 static struct intel_mid_wdt_pdata tangier_pdata = {
52 .irq = TANGIER_EXT_TIMER0_MSI,
53 .probe = tangier_probe,
56 static int wdt_scu_status_change(struct notifier_block *nb,
57 unsigned long code, void *data)
59 if (code == SCU_DOWN) {
60 platform_device_unregister(&wdt_dev);
64 return platform_device_register(&wdt_dev);
67 static struct notifier_block wdt_scu_notifier = {
68 .notifier_call = wdt_scu_status_change,
71 static int __init register_mid_wdt(void)
73 if (intel_mid_identify_cpu() != INTEL_MID_CPU_CHIP_TANGIER)
76 wdt_dev.dev.platform_data = &tangier_pdata;
79 * We need to be sure that the SCU IPC is ready before watchdog device
82 intel_scu_notifier_add(&wdt_scu_notifier);
86 rootfs_initcall(register_mid_wdt);