/* * ACPI GSI IRQ layer * * Copyright (C) 2015 ARM Ltd. * Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include <linux/acpi.h> #include <linux/irq.h> #include <linux/irqdomain.h> enum acpi_irq_model_id acpi_irq_model; static unsigned int acpi_gsi_get_irq_type(int trigger, int polarity) { switch (polarity) { case ACPI_ACTIVE_LOW: return trigger == ACPI_EDGE_SENSITIVE ? IRQ_TYPE_EDGE_FALLING : IRQ_TYPE_LEVEL_LOW; case ACPI_ACTIVE_HIGH: return trigger == ACPI_EDGE_SENSITIVE ? IRQ_TYPE_EDGE_RISING : IRQ_TYPE_LEVEL_HIGH; case ACPI_ACTIVE_BOTH: if (trigger == ACPI_EDGE_SENSITIVE) return IRQ_TYPE_EDGE_BOTH; default: return IRQ_TYPE_NONE; } } /** * acpi_gsi_to_irq() - Retrieve the linux irq number for a given GSI * @gsi: GSI IRQ number to map * @irq: pointer where linux IRQ number is stored * * irq location updated with irq value [>0 on success, 0 on failure] * * Returns: linux IRQ number on success (>0) * -EINVAL on failure */ int acpi_gsi_to_irq(u32 gsi, unsigned int *irq) { /* * Only default domain is supported at present, always find * the mapping corresponding to default domain by passing NULL * as irq_domain parameter */ *irq = irq_find_mapping(NULL, gsi); /* * *irq == 0 means no mapping, that should * be reported as a failure */ return (*irq > 0) ? *irq : -EINVAL; } EXPORT_SYMBOL_GPL(acpi_gsi_to_irq); /** * acpi_register_gsi() - Map a GSI to a linux IRQ number * @dev: device for which IRQ has to be mapped * @gsi: GSI IRQ number * @trigger: trigger type of the GSI number to be mapped * @polarity: polarity of the GSI to be mapped * * Returns: a valid linux IRQ number on success * -EINVAL on failure */ int acpi_register_gsi(struct device *dev, u32 gsi, int trigger, int polarity) { unsigned int irq; unsigned int irq_type = acpi_gsi_get_irq_type(trigger, polarity); /* * There is no way at present to look-up the IRQ domain on ACPI, * hence always create mapping referring to the default domain * by passing NULL as irq_domain parameter */ irq = irq_create_mapping(NULL, gsi); if (!irq) return -EINVAL; /* Set irq type if specified and different than the current one */ if (irq_type != IRQ_TYPE_NONE && irq_type != irq_get_trigger_type(irq)) irq_set_irq_type(irq, irq_type); return irq; } EXPORT_SYMBOL_GPL(acpi_register_gsi); /** * acpi_unregister_gsi() - Free a GSI<->linux IRQ number mapping * @gsi: GSI IRQ number */ void acpi_unregister_gsi(u32 gsi) { int irq = irq_find_mapping(NULL, gsi); irq_dispose_mapping(irq); } EXPORT_SYMBOL_GPL(acpi_unregister_gsi);