--- /dev/null
+/*
+ * Copyright (C) 2007 Google, Inc.
+ * Copyright (C) 2011 Intel, Inc.
+ * Copyright (C) 2013 Intel, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+
+#define PDEV_BUS_OP_DONE (0x00)
+#define PDEV_BUS_OP_REMOVE_DEV (0x04)
+#define PDEV_BUS_OP_ADD_DEV (0x08)
+
+#define PDEV_BUS_OP_INIT (0x00)
+
+#define PDEV_BUS_OP (0x00)
+#define PDEV_BUS_GET_NAME (0x04)
+#define PDEV_BUS_NAME_LEN (0x08)
+#define PDEV_BUS_ID (0x0c)
+#define PDEV_BUS_IO_BASE (0x10)
+#define PDEV_BUS_IO_SIZE (0x14)
+#define PDEV_BUS_IRQ (0x18)
+#define PDEV_BUS_IRQ_COUNT (0x1c)
+
+struct pdev_bus_dev {
+ struct list_head list;
+ struct platform_device pdev;
+ struct resource resources[0];
+};
+
+static void goldfish_pdev_worker(struct work_struct *work);
+
+static void __iomem *pdev_bus_base;
+static unsigned long pdev_bus_addr;
+static unsigned long pdev_bus_len;
+static u32 pdev_bus_irq;
+static LIST_HEAD(pdev_bus_new_devices);
+static LIST_HEAD(pdev_bus_registered_devices);
+static LIST_HEAD(pdev_bus_removed_devices);
+static DECLARE_WORK(pdev_bus_worker, goldfish_pdev_worker);
+
+
+static void goldfish_pdev_worker(struct work_struct *work)
+{
+ int ret;
+ struct pdev_bus_dev *pos, *n;
+
+ list_for_each_entry_safe(pos, n, &pdev_bus_removed_devices, list) {
+ list_del(&pos->list);
+ platform_device_unregister(&pos->pdev);
+ kfree(pos);
+ }
+ list_for_each_entry_safe(pos, n, &pdev_bus_new_devices, list) {
+ list_del(&pos->list);
+ ret = platform_device_register(&pos->pdev);
+ if (ret)
+ pr_err("goldfish_pdev_worker failed to register device, %s\n",
+ pos->pdev.name);
+ list_add_tail(&pos->list, &pdev_bus_registered_devices);
+ }
+}
+
+static void goldfish_pdev_remove(void)
+{
+ struct pdev_bus_dev *pos, *n;
+ u32 base;
+
+ base = readl(pdev_bus_base + PDEV_BUS_IO_BASE);
+
+ list_for_each_entry_safe(pos, n, &pdev_bus_new_devices, list) {
+ if (pos->resources[0].start == base) {
+ list_del(&pos->list);
+ kfree(pos);
+ return;
+ }
+ }
+ list_for_each_entry_safe(pos, n, &pdev_bus_registered_devices, list) {
+ if (pos->resources[0].start == base) {
+ list_del(&pos->list);
+ list_add_tail(&pos->list, &pdev_bus_removed_devices);
+ schedule_work(&pdev_bus_worker);
+ return;
+ }
+ };
+ pr_err("goldfish_pdev_remove could not find device at %x\n", base);
+}
+
+static int goldfish_new_pdev(void)
+{
+ struct pdev_bus_dev *dev;
+ u32 name_len;
+ u32 irq = -1, irq_count;
+ int resource_count = 2;
+ u32 base;
+ char *name;
+
+ base = readl(pdev_bus_base + PDEV_BUS_IO_BASE);
+
+ irq_count = readl(pdev_bus_base + PDEV_BUS_IRQ_COUNT);
+ name_len = readl(pdev_bus_base + PDEV_BUS_NAME_LEN);
+ if (irq_count)
+ resource_count++;
+
+ dev = kzalloc(sizeof(*dev) +
+ sizeof(struct resource) * resource_count +
+ name_len + 1 + sizeof(*dev->pdev.dev.dma_mask), GFP_ATOMIC);
+ if (dev == NULL)
+ return -ENOMEM;
+
+ dev->pdev.num_resources = resource_count;
+ dev->pdev.resource = (struct resource *)(dev + 1);
+ dev->pdev.name = name = (char *)(dev->pdev.resource + resource_count);
+ dev->pdev.dev.coherent_dma_mask = ~0;
+ dev->pdev.dev.dma_mask = (void *)(dev->pdev.name + name_len + 1);
+ *dev->pdev.dev.dma_mask = ~0;
+
+ writel((unsigned long)name, pdev_bus_base + PDEV_BUS_GET_NAME);
+ name[name_len] = '\0';
+ dev->pdev.id = readl(pdev_bus_base + PDEV_BUS_ID);
+ dev->pdev.resource[0].start = base;
+ dev->pdev.resource[0].end = base +
+ readl(pdev_bus_base + PDEV_BUS_IO_SIZE) - 1;
+ dev->pdev.resource[0].flags = IORESOURCE_MEM;
+ if (irq_count) {
+ irq = readl(pdev_bus_base + PDEV_BUS_IRQ);
+ dev->pdev.resource[1].start = irq;
+ dev->pdev.resource[1].end = irq + irq_count - 1;
+ dev->pdev.resource[1].flags = IORESOURCE_IRQ;
+ }
+
+ pr_debug("goldfish_new_pdev %s at %x irq %d\n", name, base, irq);
+ list_add_tail(&dev->list, &pdev_bus_new_devices);
+ schedule_work(&pdev_bus_worker);
+
+ return 0;
+}
+
+static irqreturn_t goldfish_pdev_bus_interrupt(int irq, void *dev_id)
+{
+ irqreturn_t ret = IRQ_NONE;
+ while (1) {
+ u32 op = readl(pdev_bus_base + PDEV_BUS_OP);
+ switch (op) {
+ case PDEV_BUS_OP_DONE:
+ return IRQ_NONE;
+
+ case PDEV_BUS_OP_REMOVE_DEV:
+ goldfish_pdev_remove();
+ break;
+
+ case PDEV_BUS_OP_ADD_DEV:
+ goldfish_new_pdev();
+ break;
+ }
+ ret = IRQ_HANDLED;
+ }
+ return ret;
+}
+
+static int goldfish_pdev_bus_probe(struct platform_device *pdev)
+{
+ int ret;
+ struct resource *r;
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (r == NULL)
+ return -EINVAL;
+
+ pdev_bus_addr = r->start;
+ pdev_bus_len = resource_size(r);
+
+ if (request_mem_region(pdev_bus_addr, pdev_bus_len, "goldfish")) {
+ dev_err(&pdev->dev, "unable to reserve Goldfish MMIO.\n");
+ return -EBUSY;
+ }
+
+ pdev_bus_base = ioremap(pdev_bus_addr, pdev_bus_len);
+ if (pdev_bus_base == NULL) {
+ ret = -ENOMEM;
+ dev_err(&pdev->dev, "unable to map Goldfish MMIO.\n");
+ goto free_resources;
+ }
+
+ r = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+ if (r == NULL) {
+ ret = -ENOENT;
+ goto free_map;
+ }
+
+ pdev_bus_irq = r->start;
+
+ ret = request_irq(pdev_bus_irq, goldfish_pdev_bus_interrupt,
+ IRQF_SHARED, "goldfish_pdev_bus", pdev);
+ if (ret) {
+ dev_err(&pdev->dev, "unable to request Goldfish IRQ\n");
+ goto free_map;
+ }
+
+ writel(PDEV_BUS_OP_INIT, pdev_bus_base + PDEV_BUS_OP);
+ return 0;
+
+free_map:
+ iounmap(pdev_bus_base);
+free_resources:
+ release_mem_region(pdev_bus_addr, pdev_bus_len);
+ return ret;
+}
+
+static int goldfish_pdev_bus_remove(struct platform_device *pdev)
+{
+ iounmap(pdev_bus_base);
+ free_irq(pdev_bus_irq, pdev);
+ release_mem_region(pdev_bus_addr, pdev_bus_len);
+ return 0;
+}
+
+static struct platform_driver goldfish_pdev_bus_driver = {
+ .probe = goldfish_pdev_bus_probe,
+ .remove = goldfish_pdev_bus_remove,
+ .driver = {
+ .name = "goldfish_pdev_bus"
+ }
+};
+
+module_platform_driver(goldfish_pdev_bus_driver);