pdev_bus.rar_SOC

/* * 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) #define PDEV_BUS_GET_NAME_HIGH (0x20) 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; #ifdef CONFIG_64BIT writel((u32)((u64)name>>32), pdev_bus_base + PDEV_BUS_GET_NAME_HIGH); #endif writel((u32)(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); 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);