ACPI: GED: unregister interrupts during shutdown

Some GED interrupts could be pending by the time we are doing a reboot.

Even though GED driver uses devm_request_irq() to register the interrupt
handler, the handler is not being freed on time during a shutdown since
the driver is missing a shutdown callback.

If the ACPI handler is no longer available, this causes an interrupt
storm and delays shutdown.

 1. Don't use devm family of functions for IRQ registration/free
 2. Keep track of the events since free_irq() requires the dev_id
    parameter passed into the request_irq() function.
 3. Call free_irq() on both remove and shutdown explicitly.

Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 41 insertions, 6 deletions

diff --git a/drivers/acpi/evged.c b/drivers/acpi/evged.c
index 46f060356a22..f13ba2c07667 100644
--- a/drivers/acpi/evged.c
+++ b/drivers/acpi/evged.c
@@ -49,6 +49,11 @@
 
 #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;
@@ -76,7 +81,8 @@ static acpi_status acpi_ged_request_interrupt(struct acpi_resource *ares,
         unsigned int irq;
         unsigned int gsi;
         unsigned int irqflags = IRQF_ONESHOT;
-        struct device *dev = context;
+        struct acpi_ged_device *geddev = context;
+        struct device *dev = geddev->dev;
         acpi_handle handle = ACPI_HANDLE(dev);
         acpi_handle evt_handle;
         struct resource r;
@@ -102,8 +108,6 @@ static acpi_status acpi_ged_request_interrupt(struct acpi_resource *ares,
                 return AE_ERROR;
         }
 
-        dev_info(dev, "GED listening GSI %u @ IRQ %u\n", gsi, irq);
-
         event = devm_kzalloc(dev, sizeof(*event), GFP_KERNEL);
         if (!event)
                 return AE_ERROR;
@@ -116,29 +120,58 @@ static acpi_status acpi_ged_request_interrupt(struct acpi_resource *ares,
         if (r.flags & IORESOURCE_IRQ_SHAREABLE)
                 irqflags |= IRQF_SHARED;
 
-        if (devm_request_threaded_irq(dev, irq, NULL, acpi_ged_irq_handler,
-                                      irqflags, "ACPI:Ged", event)) {
+        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, &pdev->dev);
+                                       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 int ged_remove(struct platform_device *pdev)
+{
+        ged_shutdown(pdev);
+        return 0;
+}
+
 static const struct acpi_device_id ged_acpi_ids[] = {
         {"ACPI0013"},
         {},
@@ -146,6 +179,8 @@ static const struct acpi_device_id ged_acpi_ids[] = {
 
 static struct platform_driver ged_driver = {
         .probe = ged_probe,
+        .remove = ged_remove,
+        .shutdown = ged_shutdown,
         .driver = {
                 .name = MODULE_NAME,
                 .acpi_match_table = ACPI_PTR(ged_acpi_ids),