/*
* 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 <linux/io.h>
#include <linux/pm.h>
#include <linux/pm_runtime.h>
#include <linux/amba/bus.h>
#include <asm/irq.h>
#include <asm/sizes.h>
#define to_amba_driver(d) container_of(d, struct amba_driver, drv)
static const struct amba_id *
amba_lookup(const 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_uevent(struct device *dev, struct kobj_uevent_env *env)
{
struct amba_device *pcdev = to_amba_device(dev);
int retval = 0;
retval = add_uevent_var(env, "AMBA_ID=%08x", pcdev->periphid);
if (retval)
return retval;
retval = add_uevent_var(env, "MODALIAS=amba:d%08X", pcdev->periphid);
return retval;
}
#else
#define amba_uevent NULL
#endif
#define amba_attr_func(name,fmt,arg...) \
static ssize_t name##_show(struct device *_dev, \
struct device_attribute *attr, char *buf) \
{ \
struct amba_device *dev = to_amba_device(_dev); \
return sprintf(buf, fmt, arg); \
}
#define amba_attr(name,fmt,arg...) \
amba_attr_func(name,fmt,arg) \
static DEVICE_ATTR(name, S_IRUGO, name##_show, NULL)
amba_attr_func(id, "%08x\n", dev->periphid);
amba_attr(irq0, "%u\n", dev->irq[0]);
amba_attr(irq1, "%u\n", dev->irq[1]);
amba_attr_func(resource, "\t%016llx\t%016llx\t%016lx\n",
(unsigned long long)dev->res.start, (unsigned long long)dev->res.end,
dev->res.flags);
static struct device_attribute amba_dev_attrs[] = {
__ATTR_RO(id),
__ATTR_RO(resource),
__ATTR_NULL,
};
#ifdef CONFIG_PM_SLEEP
static int amba_legacy_suspend(struct device *dev, pm_message_t mesg)
{
struct amba_driver *adrv = to_amba_driver(dev->driver);
struct amba_device *adev = to_amba_device(dev);
int ret = 0;
if (dev->driver && adrv->suspend)
ret = adrv->suspend(adev, mesg);
return ret;
}
static int amba_legacy_resume(struct device *dev)
{
struct amba_driver *adrv = to_amba_driver(dev->driver);
struct amba_device *adev = to_amba_device(dev);
int ret = 0;
if (dev->driver && adrv->resume)
ret = adrv->resume(adev);
return ret;
}
#endif /* CONFIG_PM_SLEEP */
#ifdef CONFIG_SUSPEND
static int amba_pm_suspend(struct device *dev)
{
struct device_driver *drv = dev->driver;
int ret = 0;
if (!drv)
return 0;
if (drv->pm) {
if (drv->pm->suspend)
ret = drv->pm->suspend(dev);
} else {
ret = amba_legacy_suspend(dev, PMSG_SUSPEND);
}
return ret;
}
static int amba_pm_resume(struct device *dev)
{
struct device_driver *drv = dev->driver;
int ret = 0;
if (!drv)
return 0;
if (drv->pm) {
if (drv->pm->resume)
ret = drv->pm->resume(dev);
} else {
ret = amba_legacy_resume(dev);
}
return ret;
}
#else /* !CONFIG_SUSPEND */
#define amba_pm_suspend NULL
#define amba_pm_resume NULL
#endif /* !CONFIG_SUSPEND */
#ifdef CONFIG_HIBERNATE_CALLBACKS
static int amba_pm_freeze(struct device *dev)
{
struct device_driver *drv = dev->driver;
int ret = 0;
if (!drv)
return 0;
if (drv->pm) {
if (drv->pm->freeze)
ret = drv->pm->freeze(dev);
} else {
ret = amba_legacy_suspend(dev, PMSG_FREEZE);
}
return ret;
}
static int amba_pm_thaw(struct device *dev)
{
struct device_driver *drv = dev->driver;
int ret = 0;
if (!drv)
return 0;
if (drv->pm) {
if (drv->pm->thaw)
ret = drv->pm->thaw(dev);
} else {
ret = amba_legacy_resume(dev);
}
return ret;
}
static int amba_pm_poweroff(struct device *dev)
{
struct device_driver *drv = dev->driver;
int ret = 0;
if (!drv)
return 0;
if (drv->pm) {
if (drv->pm->poweroff)
ret = drv->pm->poweroff(dev);
} else {
ret = amba_legacy_suspend(dev, PMSG_HIBERNATE);
}
return ret;
}
static int amba_pm_restore(struct device *dev)
{
struct device_driver *drv = dev->driver;
int ret = 0;
if (!drv)
return 0;
if (drv->pm) {
if (drv->pm->restore)
ret = drv->pm->restore(dev);
} else {
ret = amba_legacy_resume(dev);
}
return ret;
}
#else /* !CONFIG_HIBERNATE_CALLBACKS */
#define amba_pm_freeze NULL
#define amba_pm_thaw NULL
#define amba_pm_poweroff NULL
#define amba_pm_restore NULL
#endif /* !CONFIG_HIBERNATE_CALLBACKS */
#ifdef CONFIG_PM_RUNTIME
/*
* Hooks to provide runtime PM of the pclk (bus clock). It is safe to
* enable/disable the bus clock at runtime PM suspend/resume as this
* does not result in loss of context. However, disabling vcore power
* would do, so we leave that to the driver.
*/
static int amba_pm_runtime_suspend(struct device *dev)
{
struct amba_device *pcdev = to_amba_device(dev);
int ret = pm_generic_runtime_suspend(dev);
if (ret == 0 && dev->driver)
clk_disable(pcdev->pclk);
return ret;
}
static int amba_pm_runtime_resume(struct device *dev)
{
struct amba_device *pcdev = to_amba_device(dev);
int ret;
if (dev->driver) {
ret = clk_enable(pcdev->pclk);
/* Failure is probably fatal to the system, but... */
if (ret)
return ret;
}
return pm_generic_runtime_resume(dev);
}
#endif
#ifdef CONFIG_PM
static const struct dev_pm_ops amba_pm = {
.suspend = amba_pm_suspend,
.resume = amba_pm_resume,
.freeze = amba_pm_freeze,
.thaw = amba_pm_thaw,
.poweroff = amba_pm_poweroff,
.restore = amba_pm_restore,
SET_RUNTIME_PM_OPS(
amba_pm_runtime_suspend,
amba_pm_runtime_resume,
pm_generic_runtime_idle
)
};
#define AMBA_PM (&amba_pm)
#else /* !CONFIG_PM */
#define AMBA_PM NULL
#endif /* !CONFIG_PM */
/*
* Primecells are part of the Advanced Microcontroller Bus Architecture,
* so we call the bus "amba".
*/
struct bus_type amba_bustype = {
.name = "amba",
.dev_attrs = amba_dev_attrs,
.match = amba_match,
.uevent = amba_uevent,
.pm = AMBA_PM,
};
static int __init amba_init(void)
{
return bus_register(&amba_bustype);
}
postcore_initcall(amba_init);
static int amba_get_enable_pclk(struct amba_device *pcdev)
{
struct clk *pclk = clk_get(&pcdev->dev, "apb_pclk");
int ret;
pcdev->pclk = pclk;
if (IS_ERR(pclk))
return PTR_ERR(pclk);
ret = clk_prepare(pclk);
if (ret) {
clk_put(pclk);
return ret;
}
ret = clk_enable(pclk);
if (ret) {
clk_unprepare(pclk);
clk_put(pclk);
}
return ret;
}
static void amba_put_disable_pclk(struct amba_device *pcdev)
{
struct clk *pclk = pcdev->pclk;
clk_disable(pclk);
clk_unprepare(pclk);
clk_put(pclk);
}
static int amba_get_enable_vcore(struct amba_device *pcdev)
{
struct regulator *vcore = regulator_get(&pcdev->dev, "vcore");
int ret;
pcdev->vcore = vcore;
if (IS_ERR(vcore)) {
/* It is OK not to supply a vcore regulator */
if (PTR_ERR(vcore) == -ENODEV)
return 0;
return PTR_ERR(vcore);
}
ret = regulator_enable(vcore);
if (ret) {
regulator_put(vcore);
pcdev->vcore = ERR_PTR(-ENODEV);
}
return ret;
}
static void amba_put_disable_vcore(struct amba_device *pcdev)
{
struct regulator *vcore = pcdev->vcore;
if (!IS_ERR(vcore)) {
regulator_disable(vcore);
regulator_put(vcore);
}
}
/*
* 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);
const struct amba_id *id = amba_lookup(pcdrv->id_table, pcdev);
int ret;
do {
ret = amba_get_enable_vcore(pcdev);
if (ret)
break;
ret = amba_get_enable_pclk(pcdev);
if (ret)
break;
pm_runtime_get_noresume(dev);
pm_runtime_set_active(dev);
pm_runtime_enable(dev);
ret = pcdrv->probe(pcdev, id);
if (ret == 0)
break;
pm_runtime_disable(dev);
pm_runtime_set_suspended(dev);
pm_runtime_put_noidle(dev);
amba_put_disable_pclk(pcdev);
amba_put_disable_vcore(pcdev);
} while (0);
return ret;
}
static int amba_remove(struct device *dev)
{
struct amba_device *pcdev = to_amba_device(dev);
struct amba_driver *drv = to_amba_driver(dev->driver);
int ret;
pm_runtime_get_sync(dev);
ret = drv->remove(pcdev);
pm_runtime_put_noidle(dev);
/* Undo the runtime PM settings in amba_probe() */
pm_runtime_disable(dev);
pm_runtime_set_suspended(dev);
pm_runtime_put_noidle(dev);
amba_put_disable_pclk(pcdev);
amba_put_disable_vcore(pcdev);
return ret;
}
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);
}
/**
* 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 size;
void __iomem *tmp;
int i, ret;
device_initialize(&dev->dev);
/*
* Copy from device_add
*/
if (dev->dev.init_name) {
dev_set_name(&dev->dev, "%s", dev->dev.init_name);
dev->dev.init_name = NULL;
}
dev->dev.release = amba_device_release;
dev->dev.bus = &amba_bustype;
dev->dev.dma_mask = &dev->dma_mask;
dev->res.name = dev_name(&dev->dev);
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)
goto err_out;
/* Hard-coded primecell ID instead of plug-n-play */
if (dev->periphid != 0)
goto skip_probe;
/*
* Dynamically calculate the size of the resource
* and use this for iomap
*/
size = resource_size(&dev->res);
tmp = ioremap(dev->res.start, size);
if (!tmp) {
ret = -ENOMEM;
goto err_release;
}
ret = amba_get_enable_pclk(dev);
if (ret == 0) {
u32 pid, cid;
/*
* Read pid and cid based on size of resource
* they are located at end of region
*/
for (pid = 0, i = 0; i < 4; i++)
pid |= (readl(tmp + size - 0x20 + 4 * i) & 255) <<
(i * 8);
for (cid = 0, i = 0; i < 4; i++)
cid |= (readl(tmp + size - 0x10 + 4 * i) & 255) <<
(i * 8);
amba_put_disable_pclk(dev);
if (cid == AMBA_CID)
dev->periphid = pid;
if (!dev->periphid)
ret = -ENODEV;
}
iounmap(tmp);
if (ret)
goto err_release;
skip_probe:
ret = device_add(&dev->dev);
if (ret)
goto err_release;
if (dev->irq[0] != NO_IRQ)
ret = device_create_file(&dev->dev, &dev_attr_irq0);
if (ret == 0 && dev->irq[1] != NO_IRQ)
ret = device_create_file(&dev->dev, &dev_attr_irq1);
if (ret == 0)
return ret;
device_unregister(&dev->dev);
err_release:
release_resource(&dev->res);
err_out:
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_name(dev), 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;
u32 size;
if (!name)
name = dev->dev.driver->name;
size = resource_size(&dev->res);
if (!request_mem_region(dev->res.start, size, name))
ret = -EBUSY;
return ret;
}
/**
* amba_release_regions - release mem regions associated 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)
{
u32 size;
size = resource_size(&dev->res);
release_mem_region(dev->res.start, size);
}
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);
