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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 | // SPDX-License-Identifier: GPL-2.0-only /* * Generic Event Device for ACPI. * * Copyright (c) 2016, The Linux Foundation. All rights reserved. * * Generic Event Device allows platforms to handle interrupts in ACPI * ASL statements. It follows very similar to _EVT method approach * from GPIO events. All interrupts are listed in _CRS and the handler * is written in _EVT method. Here is an example. * * Device (GED0) * { * * Name (_HID, "ACPI0013") * Name (_UID, 0) * Method (_CRS, 0x0, Serialized) * { * Name (RBUF, ResourceTemplate () * { * Interrupt(ResourceConsumer, Edge, ActiveHigh, Shared, , , ) * {123} * } * }) * * Method (_EVT, 1) { * if (Lequal(123, Arg0)) * { * } * } * } */ #include <linux/err.h> #include <linux/init.h> #include <linux/interrupt.h> #include <linux/list.h> #include <linux/platform_device.h> #include <linux/acpi.h> #define MODULE_NAME "acpi-ged" struct acpi_ged_device { struct device *dev; struct list_head event_list; }; struct acpi_ged_event { struct list_head node; struct device *dev; unsigned int gsi; unsigned int irq; acpi_handle handle; }; static irqreturn_t acpi_ged_irq_handler(int irq, void *data) { struct acpi_ged_event *event = data; acpi_status acpi_ret; acpi_ret = acpi_execute_simple_method(event->handle, NULL, event->gsi); if (ACPI_FAILURE(acpi_ret)) dev_err_once(event->dev, "IRQ method execution failed\n"); return IRQ_HANDLED; } static acpi_status acpi_ged_request_interrupt(struct acpi_resource *ares, void *context) { struct acpi_ged_event *event; unsigned int irq; unsigned int gsi; unsigned int irqflags = IRQF_ONESHOT; struct acpi_ged_device *geddev = context; struct device *dev = geddev->dev; acpi_handle handle = ACPI_HANDLE(dev); acpi_handle evt_handle; struct resource r; struct acpi_resource_irq *p = &ares->data.irq; struct acpi_resource_extended_irq *pext = &ares->data.extended_irq; char ev_name[5]; u8 trigger; if (ares->type == ACPI_RESOURCE_TYPE_END_TAG) return AE_OK; if (!acpi_dev_resource_interrupt(ares, 0, &r)) { dev_err(dev, "unable to parse IRQ resource\n"); return AE_ERROR; } if (ares->type == ACPI_RESOURCE_TYPE_IRQ) { gsi = p->interrupts[0]; trigger = p->triggering; } else { gsi = pext->interrupts[0]; trigger = pext->triggering; } irq = r.start; switch (gsi) { case 0 ... 255: sprintf(ev_name, "_%c%02X", trigger == ACPI_EDGE_SENSITIVE ? 'E' : 'L', gsi); if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle))) break; fallthrough; default: if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle))) break; dev_err(dev, "cannot locate _EVT method\n"); return AE_ERROR; } event = devm_kzalloc(dev, sizeof(*event), GFP_KERNEL); if (!event) return AE_ERROR; event->gsi = gsi; event->dev = dev; event->irq = irq; event->handle = evt_handle; if (r.flags & IORESOURCE_IRQ_SHAREABLE) irqflags |= IRQF_SHARED; if (request_threaded_irq(irq, NULL, acpi_ged_irq_handler, irqflags, "ACPI:Ged", event)) { dev_err(dev, "failed to setup event handler for irq %u\n", irq); return AE_ERROR; } dev_dbg(dev, "GED listening GSI %u @ IRQ %u\n", gsi, irq); list_add_tail(&event->node, &geddev->event_list); return AE_OK; } static int ged_probe(struct platform_device *pdev) { struct acpi_ged_device *geddev; acpi_status acpi_ret; geddev = devm_kzalloc(&pdev->dev, sizeof(*geddev), GFP_KERNEL); if (!geddev) return -ENOMEM; geddev->dev = &pdev->dev; INIT_LIST_HEAD(&geddev->event_list); acpi_ret = acpi_walk_resources(ACPI_HANDLE(&pdev->dev), "_CRS", acpi_ged_request_interrupt, geddev); if (ACPI_FAILURE(acpi_ret)) { dev_err(&pdev->dev, "unable to parse the _CRS record\n"); return -EINVAL; } platform_set_drvdata(pdev, geddev); return 0; } static void ged_shutdown(struct platform_device *pdev) { struct acpi_ged_device *geddev = platform_get_drvdata(pdev); struct acpi_ged_event *event, *next; list_for_each_entry_safe(event, next, &geddev->event_list, node) { free_irq(event->irq, event); list_del(&event->node); dev_dbg(geddev->dev, "GED releasing GSI %u @ IRQ %u\n", event->gsi, event->irq); } } static void ged_remove(struct platform_device *pdev) { ged_shutdown(pdev); } static const struct acpi_device_id ged_acpi_ids[] = { {"ACPI0013"}, {}, }; static struct platform_driver ged_driver = { .probe = ged_probe, .remove_new = ged_remove, .shutdown = ged_shutdown, .driver = { .name = MODULE_NAME, .acpi_match_table = ACPI_PTR(ged_acpi_ids), }, }; builtin_platform_driver(ged_driver); |