Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 | /*
* 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);
|