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1// SPDX-License-Identifier: GPL-2.0-only2 3/*4 * ACPI support for platform bus type.5 *6 * Copyright (C) 2015, Linaro Ltd7 * Author: Graeme Gregory <graeme.gregory@linaro.org>8 */9 10#include <linux/acpi.h>11#include <linux/amba/bus.h>12#include <linux/clkdev.h>13#include <linux/clk-provider.h>14#include <linux/device.h>15#include <linux/err.h>16#include <linux/ioport.h>17#include <linux/kernel.h>18#include <linux/module.h>19 20#include "init.h"21 22static const struct acpi_device_id amba_id_list[] = {23 {"ARMH0061", 0}, /* PL061 GPIO Device */24 {"ARMH0330", 0}, /* ARM DMA Controller DMA-330 */25 {"", 0},26};27 28static void amba_register_dummy_clk(void)29{30 struct clk *amba_dummy_clk;31 32 amba_dummy_clk = clk_register_fixed_rate(NULL, "apb_pclk", NULL, 0, 0);33 clk_register_clkdev(amba_dummy_clk, "apb_pclk", NULL);34}35 36static int amba_handler_attach(struct acpi_device *adev,37 const struct acpi_device_id *id)38{39 struct acpi_device *parent = acpi_dev_parent(adev);40 struct amba_device *dev;41 struct resource_entry *rentry;42 struct list_head resource_list;43 bool address_found = false;44 int irq_no = 0;45 int ret;46 47 /* If the ACPI node already has a physical device attached, skip it. */48 if (adev->physical_node_count)49 return 0;50 51 dev = amba_device_alloc(dev_name(&adev->dev), 0, 0);52 if (!dev) {53 dev_err(&adev->dev, "%s(): amba_device_alloc() failed\n",54 __func__);55 return -ENOMEM;56 }57 58 INIT_LIST_HEAD(&resource_list);59 ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);60 if (ret < 0)61 goto err_free;62 63 list_for_each_entry(rentry, &resource_list, node) {64 switch (resource_type(rentry->res)) {65 case IORESOURCE_MEM:66 if (!address_found) {67 dev->res = *rentry->res;68 dev->res.name = dev_name(&dev->dev);69 address_found = true;70 }71 break;72 case IORESOURCE_IRQ:73 if (irq_no < AMBA_NR_IRQS)74 dev->irq[irq_no++] = rentry->res->start;75 break;76 default:77 dev_warn(&adev->dev, "Invalid resource\n");78 break;79 }80 }81 82 acpi_dev_free_resource_list(&resource_list);83 84 /*85 * If the ACPI node has a parent and that parent has a physical device86 * attached to it, that physical device should be the parent of87 * the amba device we are about to create.88 */89 if (parent)90 dev->dev.parent = acpi_get_first_physical_node(parent);91 92 device_set_node(&dev->dev, acpi_fwnode_handle(adev));93 94 ret = amba_device_add(dev, &iomem_resource);95 if (ret) {96 dev_err(&adev->dev, "%s(): amba_device_add() failed (%d)\n",97 __func__, ret);98 goto err_free;99 }100 101 return 1;102 103err_free:104 amba_device_put(dev);105 return ret;106}107 108static struct acpi_scan_handler amba_handler = {109 .ids = amba_id_list,110 .attach = amba_handler_attach,111};112 113void __init acpi_amba_init(void)114{115 amba_register_dummy_clk();116 acpi_scan_add_handler(&amba_handler);117}118