/*
* linux/arch/arm/common/amba.c
*
* Copyright (C) 2003 Deep Blue Solutions Ltd, All Rights Reserved.
*
* 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/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/hardware/amba.h>
#include <asm/sizes.h>
#define to_amba_device(d) container_of(d, struct amba_device, dev)
#define to_amba_driver(d) container_of(d, struct amba_driver, drv)
static struct amba_id *
amba_lookup(struct amba_id *table, struct amba_device *dev)
{
int ret = 0;
while (table->mask) {
ret = (dev->periphid & table->mask) == table->id;
if (ret)
break;
table++;
}
return ret ? table : NULL;
}
static int amba_match(struct device *dev, struct device_driver *drv)
{
struct amba_device *pcdev = to_amba_device(dev);
struct amba_driver *pcdrv = to_amba_driver(drv);
return amba_lookup(pcdrv->id_table, pcdev) != NULL;
}
#ifdef CONFIG_HOTPLUG
static int amba_hotplug(struct device *dev, char **envp, int nr_env, char *buf, int bufsz)
{
struct amba_device *pcdev = to_amba_device(dev);
if (nr_env < 2)
return -ENOMEM;
snprintf(buf, bufsz, "AMBA_ID=%08x", pcdev->periphid);
*envp++ = buf;
*envp++ = NULL;
return 0;
}
#else
#define amba_hotplug NULL
#endif
static int amba_suspend(struct device *dev, pm_message_t state)
{
struct amba_driver *drv = to_amba_driver(dev->driver);
int ret = 0;
if (dev->driver && drv->suspend)
ret = drv->suspend(to_amba_device(dev), state);
return ret;
}
static int amba_resume(struct device *dev)
{
struct amba_driver *drv = to_amba_driver(dev->driver);
int ret = 0;
if (dev->driver && drv->resume)
ret = drv->resume(to_amba_device(dev));
return ret;
}
/*
* Primecells are part of the Advanced Microcontroller Bus Architecture,
* so we call the bus "amba".
*/
static struct bus_type amba_bustype = {
.name = "amba",
.match = amba_match,
.hotplug = amba_hotplug,
.suspend = amba_suspend,
.resume = amba_resume,
};
static int __init amba_init(void)
{
return bus_register(&amba_bustype);
}
postcore_initcall(amba_init);
/*
* These are the device model conversion veneers; they convert the
* device model structures to our more specific structures.
*/
static int amba_probe(struct device *dev)
{
struct amba_device *pcdev = to_amba_device(dev);
struct amba_driver *pcdrv = to_amba_driver(dev->driver);
struct amba_id *id;
id = amba_lookup(pcdrv->id_table, pcdev);
return pcdrv->probe(pcdev, id);
}
static int amba_remove(struct device *dev)
{
struct amba_driver *drv = to_amba_driver(dev->driver);
return drv->remove(to_amba_device(dev));
}
static void amba_shutdown(struct device *dev)
{
struct amba_driver *drv = to_amba_driver(dev->driver);
drv->shutdown(to_amba_device(dev));
}
/**
* amba_driver_register - register an AMBA device driver
* @drv: amba device driver structure
*
* Register an AMBA device driver with the Linux device model
* core. If devices pre-exist, the drivers probe function will
* be called.
*/
int amba_driver_register(struct amba_driver *drv)
{
drv->drv.bus = &amba_bustype;
#define SETFN(fn) if (drv->fn) drv->drv.fn = amba_##fn
SETFN(probe);
SETFN(remove);
SETFN(shutdown);
return driver_register(&drv->drv);
}
/**
* amba_driver_unregister - remove an AMBA device driver
* @drv: AMBA device driver structure to remove
*
* Unregister an AMBA device driver from the Linux device
* model. The device model will call the drivers remove function
* for each device the device driver is currently handling.
*/
void amba_driver_unregister(struct amba_driver *drv)
{
driver_unregister(&drv->drv);
}
static void amba_device_release(struct device *dev)
{
struct amba_device *d = to_amba_device(dev);
if (d->res.parent)
release_resource(&d->res);
kfree(d);
}
#define amba_attr(name,fmt,arg...) \
static ssize_t show_##name(struct device *_dev, struct device_attribute *attr, char *buf) \
{ \
struct amba_device *dev = to_amba_device(_dev); \
return sprintf(buf, fmt, arg); \
} \
static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
amba_attr(id, "%08x\n", dev->periphid);
amba_attr(irq0, "%u\n", dev->irq[0]);
amba_attr(irq1, "%u\n", dev->irq[1]);
amba_attr(resource, "\t%08lx\t%08lx\t%08lx\n",
dev->res.start, dev->res.end, dev->res.flags);
/**
* amba_device_register - register an AMBA device
* @dev: AMBA device to register
* @parent: parent memory resource
*
* Setup the AMBA device, reading the cell ID if present.
* Claim the resource, and register the AMBA device with
* the Linux device manager.
*/
int amba_device_register(struct amba_device *dev, struct resource *parent)
{
u32 pid, cid;
void __iomem *tmp;
int i, ret;
dev->dev.release = amba_device_release;
dev->dev.bus = &amba_bustype;
dev->dev.dma_mask = &dev->dma_mask;
dev->res.name = dev->dev.bus_id;
if (!dev->dev.coherent_dma_mask && dev->dma_mask)
dev_warn(&dev->dev, "coherent dma mask is unset\n");
ret = request_resource(parent, &dev->res);
if (ret == 0) {
tmp = ioremap(dev->res.start, SZ_4K);
if (!tmp) {
ret = -ENOMEM;
goto out;
}
for (pid = 0, i = 0; i < 4; i++)
pid |= (readl(tmp + 0xfe0 + 4 * i) & 255) << (i * 8);
for (cid = 0, i = 0; i < 4; i++)
cid |= (readl(tmp + 0xff0 + 4 * i) & 255) << (i * 8);
iounmap(tmp);
if (cid == 0xb105f00d)
dev->periphid = pid;
if (dev->periphid)
ret = device_register(&dev->dev);
else
ret = -ENODEV;
if (ret == 0) {
device_create_file(&dev->dev, &dev_attr_id);
if (dev->irq[0] != NO_IRQ)
device_create_file(&dev->dev, &dev_attr_irq0);
if (dev->irq[1] != NO_IRQ)
device_create_file(&dev->dev, &dev_attr_irq1);
device_create_file(&dev->dev, &dev_attr_resource);
} else {
out:
release_resource(&dev->res);
}
}
return ret;
}
/**
* amba_device_unregister - unregister an AMBA device
* @dev: AMBA device to remove
*
* Remove the specified AMBA device from the Linux device
* manager. All files associated with this object will be
* destroyed, and device drivers notified that the device has
* been removed. The AMBA device's resources including
* the amba_device structure will be freed once all
* references to it have been dropped.
*/
void amba_device_unregister(struct amba_device *dev)
{
device_unregister(&dev->dev);
}
struct find_data {
struct amba_device *dev;
struct device *parent;
const char *busid;
unsigned int id;
unsigned int mask;
};
static int amba_find_match(struct device *dev, void *data)
{
struct find_data *d = data;
struct amba_device *pcdev = to_amba_device(dev);
int r;
r = (pcdev->periphid & d->mask) == d->id;
if (d->parent)
r &= d->parent == dev->parent;
if (d->busid)
r &= strcmp(dev->bus_id, d->busid) == 0;
if (r) {
get_device(dev);
d->dev = pcdev;
}
return r;
}
/**
* amba_find_device - locate an AMBA device given a bus id
* @busid: bus id for device (or NULL)
* @parent: parent device (or NULL)
* @id: peripheral ID (or 0)
* @mask: peripheral ID mask (or 0)
*
* Return the AMBA device corresponding to the supplied parameters.
* If no device matches, returns NULL.
*
* NOTE: When a valid device is found, its refcount is
* incremented, and must be decremented before the returned
* reference.
*/
struct amba_device *
amba_find_device(const char *busid, struct device *parent, unsigned int id,
unsigned int mask)
{
struct find_data data;
data.dev = NULL;
data.parent = parent;
data.busid = busid;
data.id = id;
data.mask = mask;
bus_for_each_dev(&amba_bustype, NULL, &data, amba_find_match);
return data.dev;
}
/**
* amba_request_regions - request all mem regions associated with device
* @dev: amba_device structure for device
* @name: name, or NULL to use driver name
*/
int amba_request_regions(struct amba_device *dev, const char *name)
{
int ret = 0;
if (!name)
name = dev->dev.driver->name;
if (!request_mem_region(dev->res.start, SZ_4K, name))
ret = -EBUSY;
return ret;
}
/**
* amba_release_regions - release mem regions assoicated with device
* @dev: amba_device structure for device
*
* Release regions claimed by a successful call to amba_request_regions.
*/
void amba_release_regions(struct amba_device *dev)
{
release_mem_region(dev->res.start, SZ_4K);
}
EXPORT_SYMBOL(amba_driver_register);
EXPORT_SYMBOL(amba_driver_unregister);
EXPORT_SYMBOL(amba_device_register);
EXPORT_SYMBOL(amba_device_unregister);
EXPORT_SYMBOL(amba_find_device);
EXPORT_SYMBOL(amba_request_regions);
EXPORT_SYMBOL(amba_release_regions);
