1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Intel Merrifield watchdog platform device library file
4 *
5 * (C) Copyright 2014 Intel Corporation
6 * Author: David Cohen <david.a.cohen@linux.intel.com>
7 */
8
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>
13
14#include <asm/cpu_device_id.h>
15#include <asm/intel-family.h>
16#include <asm/io_apic.h>
17#include <asm/hw_irq.h>
18
19#define TANGIER_EXT_TIMER0_MSI 12
20
21static struct platform_device wdt_dev = {
22 .name = "intel_mid_wdt",
23 .id = -1,
24};
25
26static int tangier_probe(struct platform_device *pdev)
27{
28 struct irq_alloc_info info;
29 struct intel_mid_wdt_pdata *pdata = pdev->dev.platform_data;
30 int gsi = TANGIER_EXT_TIMER0_MSI;
31 int irq;
32
33 if (!pdata)
34 return -EINVAL;
35
36 /* IOAPIC builds identity mapping between GSI and IRQ on MID */
37 ioapic_set_alloc_attr(info: &info, cpu_to_node(cpu: 0), trigger: 1, polarity: 0);
38 irq = mp_map_gsi_to_irq(gsi, IOAPIC_MAP_ALLOC, info: &info);
39 if (irq < 0) {
40 dev_warn(&pdev->dev, "cannot find interrupt %d in ioapic\n", gsi);
41 return irq;
42 }
43
44 pdata->irq = irq;
45 return 0;
46}
47
48static struct intel_mid_wdt_pdata tangier_pdata = {
49 .probe = tangier_probe,
50};
51
52static const struct x86_cpu_id intel_mid_cpu_ids[] = {
53 X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT_MID, &tangier_pdata),
54 {}
55};
56
57static int __init register_mid_wdt(void)
58{
59 const struct x86_cpu_id *id;
60
61 id = x86_match_cpu(match: intel_mid_cpu_ids);
62 if (!id)
63 return -ENODEV;
64
65 wdt_dev.dev.platform_data = (struct intel_mid_wdt_pdata *)id->driver_data;
66 return platform_device_register(&wdt_dev);
67}
68arch_initcall(register_mid_wdt);
69
70static void __exit unregister_mid_wdt(void)
71{
72 platform_device_unregister(&wdt_dev);
73}
74__exitcall(unregister_mid_wdt);
75

source code of linux/drivers/platform/x86/intel_scu_wdt.c