1 // SPDX-License-Identifier: GPL-2.0-only
3 * Intel Merrifield watchdog platform device library file
5 * (C) Copyright 2014 Intel Corporation
6 * Author: David Cohen <david.a.cohen@linux.intel.com>
9 #include <linux/init.h>
10 #include <linux/interrupt.h>
11 #include <linux/platform_device.h>
12 #include <linux/platform_data/intel-mid_wdt.h>
14 #include <asm/intel-mid.h>
15 #include <asm/intel_scu_ipc.h>
16 #include <asm/io_apic.h>
17 #include <asm/hw_irq.h>
19 #define TANGIER_EXT_TIMER0_MSI 12
21 static struct platform_device wdt_dev = {
22 .name = "intel_mid_wdt",
26 static int tangier_probe(struct platform_device *pdev)
28 struct irq_alloc_info info;
29 struct intel_mid_wdt_pdata *pdata = pdev->dev.platform_data;
30 int gsi = TANGIER_EXT_TIMER0_MSI;
36 /* IOAPIC builds identity mapping between GSI and IRQ on MID */
37 ioapic_set_alloc_attr(&info, cpu_to_node(0), 1, 0);
38 irq = mp_map_gsi_to_irq(gsi, IOAPIC_MAP_ALLOC, &info);
40 dev_warn(&pdev->dev, "cannot find interrupt %d in ioapic\n", gsi);
48 static struct intel_mid_wdt_pdata tangier_pdata = {
49 .probe = tangier_probe,
52 static int wdt_scu_status_change(struct notifier_block *nb,
53 unsigned long code, void *data)
55 if (code == SCU_DOWN) {
56 platform_device_unregister(&wdt_dev);
60 return platform_device_register(&wdt_dev);
63 static struct notifier_block wdt_scu_notifier = {
64 .notifier_call = wdt_scu_status_change,
67 static int __init register_mid_wdt(void)
69 if (intel_mid_identify_cpu() != INTEL_MID_CPU_CHIP_TANGIER)
72 wdt_dev.dev.platform_data = &tangier_pdata;
75 * We need to be sure that the SCU IPC is ready before watchdog device
78 intel_scu_notifier_add(&wdt_scu_notifier);
82 arch_initcall(register_mid_wdt);