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/intel-mid.h> 17 #include <asm/io_apic.h> 18 #include <asm/hw_irq.h> 19 20 #define TANGIER_EXT_TIMER0_MSI 12 21 22 static struct platform_device wdt_dev = { 23 .name = "intel_mid_wdt", 24 .id = -1, 25 }; 26 27 static int tangier_probe(struct platform_device *pdev) 28 { 29 struct irq_alloc_info info; 30 struct intel_mid_wdt_pdata *pdata = pdev->dev.platform_data; 31 int gsi = TANGIER_EXT_TIMER0_MSI; 32 int irq; 33 34 if (!pdata) 35 return -EINVAL; 36 37 /* IOAPIC builds identity mapping between GSI and IRQ on MID */ 38 ioapic_set_alloc_attr(&info, cpu_to_node(0), 1, 0); 39 irq = mp_map_gsi_to_irq(gsi, IOAPIC_MAP_ALLOC, &info); 40 if (irq < 0) { 41 dev_warn(&pdev->dev, "cannot find interrupt %d in ioapic\n", gsi); 42 return irq; 43 } 44 45 pdata->irq = irq; 46 return 0; 47 } 48 49 static struct intel_mid_wdt_pdata tangier_pdata = { 50 .probe = tangier_probe, 51 }; 52 53 static const struct x86_cpu_id intel_mid_cpu_ids[] = { 54 X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT_MID, &tangier_pdata), 55 {} 56 }; 57 58 static int __init register_mid_wdt(void) 59 { 60 const struct x86_cpu_id *id; 61 62 id = x86_match_cpu(intel_mid_cpu_ids); 63 if (!id) 64 return -ENODEV; 65 66 wdt_dev.dev.platform_data = (struct intel_mid_wdt_pdata *)id->driver_data; 67 return platform_device_register(&wdt_dev); 68 } 69 arch_initcall(register_mid_wdt); 70 71 static void __exit unregister_mid_wdt(void) 72 { 73 platform_device_unregister(&wdt_dev); 74 } 75 __exitcall(unregister_mid_wdt); 76