Linux-2.6.33.2/drivers/base/platform.c
/*
* platform.c - platform 'pseudo' bus for legacy devices
*
* Copyright (c) 2002-3 Patrick Mochel
* Copyright (c) 2002-3 Open Source Development Labs
*
* This file is released under the GPLv2
*
* Please see Documentation/driver-model/platform.txt for more
* information.
*/
#include <linux/string.h>
#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/dma-mapping.h>
#include <linux/bootmem.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/pm_runtime.h>
#include "base.h"
#define to_platform_driver(drv) (container_of((drv), struct platform_driver, \
driver))
struct device platform_bus = {
.init_name = "platform",
};
EXPORT_SYMBOL_GPL(platform_bus);
/**
* platform_get_resource - get a resource for a device
* @dev: platform device
* @type: resource type
* @num: resource index
*/
struct resource *platform_get_resource(struct platform_device *dev,
unsigned int type, unsigned int num)
{
int i;
for (i = 0; i < dev->num_resources; i++) {
struct resource *r = &dev->resource[i];
if (type == resource_type(r) && num-- == 0)
return r;
}
return NULL;
}
EXPORT_SYMBOL_GPL(platform_get_resource);
/**
* platform_get_irq - get an IRQ for a device
* @dev: platform device
* @num: IRQ number index
*/
int platform_get_irq(struct platform_device *dev, unsigned int num)
{
struct resource *r = platform_get_resource(dev, IORESOURCE_IRQ, num);
return r ? r->start : -ENXIO;
}
EXPORT_SYMBOL_GPL(platform_get_irq);
/**
* platform_get_resource_byname - get a resource for a device by name
* @dev: platform device
* @type: resource type
* @name: resource name
*/
struct resource *platform_get_resource_byname(struct platform_device *dev,
unsigned int type,
const char *name)
{
int i;
for (i = 0; i < dev->num_resources; i++) {
struct resource *r = &dev->resource[i];
if (type == resource_type(r) && !strcmp(r->name, name))
return r;
}
return NULL;
}
EXPORT_SYMBOL_GPL(platform_get_resource_byname);
/**
* platform_get_irq - get an IRQ for a device
* @dev: platform device
* @name: IRQ name
*/
int platform_get_irq_byname(struct platform_device *dev, const char *name)
{
struct resource *r = platform_get_resource_byname(dev, IORESOURCE_IRQ,
name);
return r ? r->start : -ENXIO;
}
EXPORT_SYMBOL_GPL(platform_get_irq_byname);
/**
* platform_add_devices - add a numbers of platform devices
* @devs: array of platform devices to add
* @num: number of platform devices in array
*/
int platform_add_devices(struct platform_device **devs, int num)
{
int i, ret = 0;
for (i = 0; i < num; i++) {
ret = platform_device_register(devs[i]);
if (ret) {
while (--i >= 0)
platform_device_unregister(devs[i]);
break;
}
}
return ret;
}
EXPORT_SYMBOL_GPL(platform_add_devices);
struct platform_object {
struct platform_device pdev;
char name[1];
};
/**
* platform_device_put
* @pdev: platform device to free
*
* Free all memory associated with a platform device. This function must
* _only_ be externally called in error cases. All other usage is a bug.
*/
void platform_device_put(struct platform_device *pdev)
{
if (pdev)
put_device(&pdev->dev);
}
EXPORT_SYMBOL_GPL(platform_device_put);
static void platform_device_release(struct device *dev)
{
struct platform_object *pa = container_of(dev, struct platform_object,
pdev.dev);
kfree(pa->pdev.dev.platform_data);
kfree(pa->pdev.resource);
kfree(pa);
}
/**
* platform_device_alloc
* @name: base name of the device we're adding
* @id: instance id
*
* Create a platform device object which can have other objects attached
* to it, and which will have attached objects freed when it is released.
*/
struct platform_device *platform_device_alloc(const char *name, int id)
{
struct platform_object *pa;
pa = kzalloc(sizeof(struct platform_object) + strlen(name), GFP_KERNEL);
if (pa) {
strcpy(pa->name, name);
pa->pdev.name = pa->name;
pa->pdev.id = id;
device_initialize(&pa->pdev.dev);
pa->pdev.dev.release = platform_device_release;
}
return pa ? &pa->pdev : NULL;
}
EXPORT_SYMBOL_GPL(platform_device_alloc);
/**
* platform_device_add_resources
* @pdev: platform device allocated by platform_device_alloc to add resources to
* @res: set of resources that needs to be allocated for the device
* @num: number of resources
*
* Add a copy of the resources to the platform device. The memory
* associated with the resources will be freed when the platform device is
* released.
*/
int platform_device_add_resources(struct platform_device *pdev,
struct resource *res, unsigned int num)
{
struct resource *r;
r = kmalloc(sizeof(struct resource) * num, GFP_KERNEL);
if (r) {
memcpy(r, res, sizeof(struct resource) * num);
pdev->resource = r;
pdev->num_resources = num;
}
return r ? 0 : -ENOMEM;
}
EXPORT_SYMBOL_GPL(platform_device_add_resources);
/**
* platform_device_add_data
* @pdev: platform device allocated by platform_device_alloc to add resources to
* @data: platform specific data for this platform device
* @size: size of platform specific data
*
* Add a copy of platform specific data to the platform device's
* platform_data pointer. The memory associated with the platform data
* will be freed when the platform device is released.
*/
int platform_device_add_data(struct platform_device *pdev, const void *data,
size_t size)
{
void *d = kmemdup(data, size, GFP_KERNEL);
if (d) {
pdev->dev.platform_data = d;
return 0;
}
return -ENOMEM;
}
EXPORT_SYMBOL_GPL(platform_device_add_data);
/**
* platform_device_add - add a platform device to device hierarchy
* @pdev: platform device we're adding
*
* This is part 2 of platform_device_register(), though may be called
* separately _iff_ pdev was allocated by platform_device_alloc().
*/
int platform_device_add(struct platform_device *pdev)
{
int i, ret = 0;
if (!pdev)
return -EINVAL;
if (!pdev->dev.parent)
pdev->dev.parent = &platform_bus;
pdev->dev.bus = &platform_bus_type;
if (pdev->id != -1)
dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
else
dev_set_name(&pdev->dev, "%s", pdev->name);
for (i = 0; i < pdev->num_resources; i++) {
struct resource *p, *r = &pdev->resource[i];
if (r->name == NULL)
r->name = dev_name(&pdev->dev);
p = r->parent;
if (!p) {
if (resource_type(r) == IORESOURCE_MEM)
p = &iomem_resource;
else if (resource_type(r) == IORESOURCE_IO)
p = &ioport_resource;
}
if (p && insert_resource(p, r)) {
printk(KERN_ERR
"%s: failed to claim resource %d\n",
dev_name(&pdev->dev), i);
ret = -EBUSY;
goto failed;
}
}
pr_debug("Registering platform device '%s'. Parent at %s\n",
dev_name(&pdev->dev), dev_name(pdev->dev.parent));
ret = device_add(&pdev->dev);
if (ret == 0)
return ret;
failed:
while (--i >= 0) {
struct resource *r = &pdev->resource[i];
unsigned long type = resource_type(r);
if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
release_resource(r);
}
return ret;
}
EXPORT_SYMBOL_GPL(platform_device_add);
/**
* platform_device_del - remove a platform-level device
* @pdev: platform device we're removing
*
* Note that this function will also release all memory- and port-based
* resources owned by the device (@dev->resource). This function must
* _only_ be externally called in error cases. All other usage is a bug.
*/
void platform_device_del(struct platform_device *pdev)
{
int i;
if (pdev) {
device_del(&pdev->dev);
for (i = 0; i < pdev->num_resources; i++) {
struct resource *r = &pdev->resource[i];
unsigned long type = resource_type(r);
if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
release_resource(r);
}
}
}
EXPORT_SYMBOL_GPL(platform_device_del);
/**
* platform_device_register - add a platform-level device
* @pdev: platform device we're adding
*/
int platform_device_register(struct platform_device *pdev)
{
device_initialize(&pdev->dev);
return platform_device_add(pdev);
}
EXPORT_SYMBOL_GPL(platform_device_register);
/**
* platform_device_unregister - unregister a platform-level device
* @pdev: platform device we're unregistering
*
* Unregistration is done in 2 steps. First we release all resources
* and remove it from the subsystem, then we drop reference count by
* calling platform_device_put().
*/
void platform_device_unregister(struct platform_device *pdev)
{
platform_device_del(pdev);
platform_device_put(pdev);
}
EXPORT_SYMBOL_GPL(platform_device_unregister);
/**
* platform_device_register_simple
* @name: base name of the device we're adding
* @id: instance id
* @res: set of resources that needs to be allocated for the device
* @num: number of resources
*
* This function creates a simple platform device that requires minimal
* resource and memory management. Canned release function freeing memory
* allocated for the device allows drivers using such devices to be
* unloaded without waiting for the last reference to the device to be
* dropped.
*
* This interface is primarily intended for use with legacy drivers which
* probe hardware directly. Because such drivers create sysfs device nodes
* themselves, rather than letting system infrastructure handle such device
* enumeration tasks, they don't fully conform to the Linux driver model.
* In particular, when such drivers are built as modules, they can't be
* "hotplugged".
*/
struct platform_device *platform_device_register_simple(const char *name,
int id,
struct resource *res,
unsigned int num)
{
struct platform_device *pdev;
int retval;
pdev = platform_device_alloc(name, id);
if (!pdev) {
retval = -ENOMEM;
goto error;
}
if (num) {
retval = platform_device_add_resources(pdev, res, num);
if (retval)
goto error;
}
retval = platform_device_add(pdev);
if (retval)
goto error;
return pdev;
error:
platform_device_put(pdev);
return ERR_PTR(retval);
}
EXPORT_SYMBOL_GPL(platform_device_register_simple);
/**
* platform_device_register_data
* @parent: parent device for the device we're adding
* @name: base name of the device we're adding
* @id: instance id
* @data: platform specific data for this platform device
* @size: size of platform specific data
*
* This function creates a simple platform device that requires minimal
* resource and memory management. Canned release function freeing memory
* allocated for the device allows drivers using such devices to be
* unloaded without waiting for the last reference to the device to be
* dropped.
*/
struct platform_device *platform_device_register_data(
struct device *parent,
const char *name, int id,
const void *data, size_t size)
{
struct platform_device *pdev;
int retval;
pdev = platform_device_alloc(name, id);
if (!pdev) {
retval = -ENOMEM;
goto error;
}
pdev->dev.parent = parent;
if (size) {
retval = platform_device_add_data(pdev, data, size);
if (retval)
goto error;
}
retval = platform_device_add(pdev);
if (retval)
goto error;
return pdev;
error:
platform_device_put(pdev);
return ERR_PTR(retval);
}
EXPORT_SYMBOL_GPL(platform_device_register_data);
static int platform_drv_probe(struct device *_dev)
{
struct platform_driver *drv = to_platform_driver(_dev->driver);
struct platform_device *dev = to_platform_device(_dev);
return drv->probe(dev);
}
static int platform_drv_probe_fail(struct device *_dev)
{
return -ENXIO;
}
static int platform_drv_remove(struct device *_dev)
{
struct platform_driver *drv = to_platform_driver(_dev->driver);
struct platform_device *dev = to_platform_device(_dev);
return drv->remove(dev);
}
static void platform_drv_shutdown(struct device *_dev)
{
struct platform_driver *drv = to_platform_driver(_dev->driver);
struct platform_device *dev = to_platform_device(_dev);
drv->shutdown(dev);
}
/**
* platform_driver_register
* @drv: platform driver structure
*/
int platform_driver_register(struct platform_driver *drv)
{
drv->driver.bus = &platform_bus_type;
if (drv->probe)
drv->driver.probe = platform_drv_probe;
if (drv->remove)
drv->driver.remove = platform_drv_remove;
if (drv->shutdown)
drv->driver.shutdown = platform_drv_shutdown;
return driver_register(&drv->driver);
}
EXPORT_SYMBOL_GPL(platform_driver_register);
/**
* platform_driver_unregister
* @drv: platform driver structure
*/
void platform_driver_unregister(struct platform_driver *drv)
{
driver_unregister(&drv->driver);
}
EXPORT_SYMBOL_GPL(platform_driver_unregister);
/**
* platform_driver_probe - register driver for non-hotpluggable device
* @drv: platform driver structure
* @probe: the driver probe routine, probably from an __init section
*
* Use this instead of platform_driver_register() when you know the device
* is not hotpluggable and has already been registered, and you want to
* remove its run-once probe() infrastructure from memory after the driver
* has bound to the device.
*
* One typical use for this would be with drivers for controllers integrated
* into system-on-chip processors, where the controller devices have been
* configured as part of board setup.
*
* Returns zero if the driver registered and bound to a device, else returns
* a negative error code and with the driver not registered.
*/
int __init_or_module platform_driver_probe(struct platform_driver *drv,
int (*probe)(struct platform_device *))
{
int retval, code;
/* make sure driver won't have bind/unbind attributes */
drv->driver.suppress_bind_attrs = true;
/* temporary section violation during probe() */
drv->probe = probe;
retval = code = platform_driver_register(drv);
/*
* Fixup that section violation, being paranoid about code scanning
* the list of drivers in order to probe new devices. Check to see
* if the probe was successful, and make sure any forced probes of
* new devices fail.
*/
spin_lock(&platform_bus_type.p->klist_drivers.k_lock);
drv->probe = NULL;
if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
retval = -ENODEV;
drv->driver.probe = platform_drv_probe_fail;
spin_unlock(&platform_bus_type.p->klist_drivers.k_lock);
if (code != retval)
platform_driver_unregister(drv);
return retval;
}
EXPORT_SYMBOL_GPL(platform_driver_probe);
/* modalias support enables more hands-off userspace setup:
* (a) environment variable lets new-style hotplug events work once system is
* fully running: "modprobe $MODALIAS"
* (b) sysfs attribute lets new-style coldplug recover from hotplug events
* mishandled before system is fully running: "modprobe $(cat modalias)"
*/
static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
char *buf)
{
struct platform_device *pdev = to_platform_device(dev);
int len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
}
static struct device_attribute platform_dev_attrs[] = {
__ATTR_RO(modalias),
__ATTR_NULL,
};
static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
{
struct platform_device *pdev = to_platform_device(dev);
add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
(pdev->id_entry) ? pdev->id_entry->name : pdev->name);
return 0;
}
static const struct platform_device_id *platform_match_id(
struct platform_device_id *id,
struct platform_device *pdev)
{
while (id->name[0]) {
if (strcmp(pdev->name, id->name) == 0) {
pdev->id_entry = id;
return id;
}
id++;
}
return NULL;
}
/**
* platform_match - bind platform device to platform driver.
* @dev: device.
* @drv: driver.
*
* Platform device IDs are assumed to be encoded like this:
* "<name><instance>", where <name> is a short description of the type of
* device, like "pci" or "floppy", and <instance> is the enumerated
* instance of the device, like '0' or '42'. Driver IDs are simply
* "<name>". So, extract the <name> from the platform_device structure,
* and compare it against the name of the driver. Return whether they match
* or not.
*/
static int platform_match(struct device *dev, struct device_driver *drv)
{
struct platform_device *pdev = to_platform_device(dev);
struct platform_driver *pdrv = to_platform_driver(drv);
/* match against the id table first */
if (pdrv->id_table)
return platform_match_id(pdrv->id_table, pdev) != NULL;
/* fall-back to driver name match */
return (strcmp(pdev->name, drv->name) == 0);
}
#ifdef CONFIG_PM_SLEEP
static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
{
struct platform_driver *pdrv = to_platform_driver(dev->driver);
struct platform_device *pdev = to_platform_device(dev);
int ret = 0;
if (dev->driver && pdrv->suspend)
ret = pdrv->suspend(pdev, mesg);
return ret;
}
static int platform_legacy_resume(struct device *dev)
{
struct platform_driver *pdrv = to_platform_driver(dev->driver);
struct platform_device *pdev = to_platform_device(dev);
int ret = 0;
if (dev->driver && pdrv->resume)
ret = pdrv->resume(pdev);
return ret;
}
static int platform_pm_prepare(struct device *dev)
{
struct device_driver *drv = dev->driver;
int ret = 0;
if (drv && drv->pm && drv->pm->prepare)
ret = drv->pm->prepare(dev);
return ret;
}
static void platform_pm_complete(struct device *dev)
{
struct device_driver *drv = dev->driver;
if (drv && drv->pm && drv->pm->complete)
drv->pm->complete(dev);
}
#else /* !CONFIG_PM_SLEEP */
#define platform_pm_prepare NULL
#define platform_pm_complete NULL
#endif /* !CONFIG_PM_SLEEP */
#ifdef CONFIG_SUSPEND
static int platform_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 = platform_legacy_suspend(dev, PMSG_SUSPEND);
}
return ret;
}
static int platform_pm_suspend_noirq(struct device *dev)
{
struct device_driver *drv = dev->driver;
int ret = 0;
if (!drv)
return 0;
if (drv->pm) {
if (drv->pm->suspend_noirq)
ret = drv->pm->suspend_noirq(dev);
}
return ret;
}
static int platform_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 = platform_legacy_resume(dev);
}
return ret;
}
static int platform_pm_resume_noirq(struct device *dev)
{
struct device_driver *drv = dev->driver;
int ret = 0;
if (!drv)
return 0;
if (drv->pm) {
if (drv->pm->resume_noirq)
ret = drv->pm->resume_noirq(dev);
}
return ret;
}
#else /* !CONFIG_SUSPEND */
#define platform_pm_suspend NULL
#define platform_pm_resume NULL
#define platform_pm_suspend_noirq NULL
#define platform_pm_resume_noirq NULL
#endif /* !CONFIG_SUSPEND */
#ifdef CONFIG_HIBERNATION
static int platform_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 = platform_legacy_suspend(dev, PMSG_FREEZE);
}
return ret;
}
static int platform_pm_freeze_noirq(struct device *dev)
{
struct device_driver *drv = dev->driver;
int ret = 0;
if (!drv)
return 0;
if (drv->pm) {
if (drv->pm->freeze_noirq)
ret = drv->pm->freeze_noirq(dev);
}
return ret;
}
static int platform_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 = platform_legacy_resume(dev);
}
return ret;
}
static int platform_pm_thaw_noirq(struct device *dev)
{
struct device_driver *drv = dev->driver;
int ret = 0;
if (!drv)
return 0;
if (drv->pm) {
if (drv->pm->thaw_noirq)
ret = drv->pm->thaw_noirq(dev);
}
return ret;
}
static int platform_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 = platform_legacy_suspend(dev, PMSG_HIBERNATE);
}
return ret;
}
static int platform_pm_poweroff_noirq(struct device *dev)
{
struct device_driver *drv = dev->driver;
int ret = 0;
if (!drv)
return 0;
if (drv->pm) {
if (drv->pm->poweroff_noirq)
ret = drv->pm->poweroff_noirq(dev);
}
return ret;
}
static int platform_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 = platform_legacy_resume(dev);
}
return ret;
}
static int platform_pm_restore_noirq(struct device *dev)
{
struct device_driver *drv = dev->driver;
int ret = 0;
if (!drv)
return 0;
if (drv->pm) {
if (drv->pm->restore_noirq)
ret = drv->pm->restore_noirq(dev);
}
return ret;
}
#else /* !CONFIG_HIBERNATION */
#define platform_pm_freeze NULL
#define platform_pm_thaw NULL
#define platform_pm_poweroff NULL
#define platform_pm_restore NULL
#define platform_pm_freeze_noirq NULL
#define platform_pm_thaw_noirq NULL
#define platform_pm_poweroff_noirq NULL
#define platform_pm_restore_noirq NULL
#endif /* !CONFIG_HIBERNATION */
#ifdef CONFIG_PM_RUNTIME
int __weak platform_pm_runtime_suspend(struct device *dev)
{
return -ENOSYS;
};
int __weak platform_pm_runtime_resume(struct device *dev)
{
return -ENOSYS;
};
int __weak platform_pm_runtime_idle(struct device *dev)
{
return -ENOSYS;
};
#else /* !CONFIG_PM_RUNTIME */
#define platform_pm_runtime_suspend NULL
#define platform_pm_runtime_resume NULL
#define platform_pm_runtime_idle NULL
#endif /* !CONFIG_PM_RUNTIME */
static const struct dev_pm_ops platform_dev_pm_ops = {
.prepare = platform_pm_prepare,
.complete = platform_pm_complete,
.suspend = platform_pm_suspend,
.resume = platform_pm_resume,
.freeze = platform_pm_freeze,
.thaw = platform_pm_thaw,
.poweroff = platform_pm_poweroff,
.restore = platform_pm_restore,
.suspend_noirq = platform_pm_suspend_noirq,
.resume_noirq = platform_pm_resume_noirq,
.freeze_noirq = platform_pm_freeze_noirq,
.thaw_noirq = platform_pm_thaw_noirq,
.poweroff_noirq = platform_pm_poweroff_noirq,
.restore_noirq = platform_pm_restore_noirq,
.runtime_suspend = platform_pm_runtime_suspend,
.runtime_resume = platform_pm_runtime_resume,
.runtime_idle = platform_pm_runtime_idle,
};
struct bus_type platform_bus_type = {
.name = "platform",
.dev_attrs = platform_dev_attrs,
.match = platform_match,
.uevent = platform_uevent,
.pm = &platform_dev_pm_ops,
};
EXPORT_SYMBOL_GPL(platform_bus_type);
int __init platform_bus_init(void)
{
int error;
early_platform_cleanup();
error = device_register(&platform_bus);
if (error)
return error;
error = bus_register(&platform_bus_type);
if (error)
device_unregister(&platform_bus);
return error;
}
#ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
u64 dma_get_required_mask(struct device *dev)
{
u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
u64 mask;
if (!high_totalram) {
/* convert to mask just covering totalram */
low_totalram = (1 << (fls(low_totalram) - 1));
low_totalram += low_totalram - 1;
mask = low_totalram;
} else {
high_totalram = (1 << (fls(high_totalram) - 1));
high_totalram += high_totalram - 1;
mask = (((u64)high_totalram) << 32) + 0xffffffff;
}
return mask;
}
EXPORT_SYMBOL_GPL(dma_get_required_mask);
#endif
static __initdata LIST_HEAD(early_platform_driver_list);
static __initdata LIST_HEAD(early_platform_device_list);
/**
* early_platform_driver_register
* @epdrv: early_platform driver structure
* @buf: string passed from early_param()
*/
int __init early_platform_driver_register(struct early_platform_driver *epdrv,
char *buf)
{
char *tmp;
int n;
/* Simply add the driver to the end of the global list.
* Drivers will by default be put on the list in compiled-in order.
*/
if (!epdrv->list.next) {
INIT_LIST_HEAD(&epdrv->list);
list_add_tail(&epdrv->list, &early_platform_driver_list);
}
/* If the user has specified device then make sure the driver
* gets prioritized. The driver of the last device specified on
* command line will be put first on the list.
*/
n = strlen(epdrv->pdrv->driver.name);
if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
list_move(&epdrv->list, &early_platform_driver_list);
/* Allow passing parameters after device name */
if (buf[n] == '\0' || buf[n] == ',')
epdrv->requested_id = -1;
else {
epdrv->requested_id = simple_strtoul(&buf[n + 1],
&tmp, 10);
if (buf[n] != '.' || (tmp == &buf[n + 1])) {
epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
n = 0;
} else
n += strcspn(&buf[n + 1], ",") + 1;
}
if (buf[n] == ',')
n++;
if (epdrv->bufsize) {
memcpy(epdrv->buffer, &buf[n],
min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
epdrv->buffer[epdrv->bufsize - 1] = '\0';
}
}
return 0;
}
/**
* early_platform_add_devices - add a numbers of early platform devices
* @devs: array of early platform devices to add
* @num: number of early platform devices in array
*/
void __init early_platform_add_devices(struct platform_device **devs, int num)
{
struct device *dev;
int i;
/* simply add the devices to list */
for (i = 0; i < num; i++) {
dev = &devs[i]->dev;
if (!dev->devres_head.next) {
INIT_LIST_HEAD(&dev->devres_head);
list_add_tail(&dev->devres_head,
&early_platform_device_list);
}
}
}
/**
* early_platform_driver_register_all
* @class_str: string to identify early platform driver class
*/
void __init early_platform_driver_register_all(char *class_str)
{
/* The "class_str" parameter may or may not be present on the kernel
* command line. If it is present then there may be more than one
* matching parameter.
*
* Since we register our early platform drivers using early_param()
* we need to make sure that they also get registered in the case
* when the parameter is missing from the kernel command line.
*
* We use parse_early_options() to make sure the early_param() gets
* called at least once. The early_param() may be called more than
* once since the name of the preferred device may be specified on
* the kernel command line. early_platform_driver_register() handles
* this case for us.
*/
parse_early_options(class_str);
}
/**
* early_platform_match
* @epdrv: early platform driver structure
* @id: id to match against
*/
static __init struct platform_device *
early_platform_match(struct early_platform_driver *epdrv, int id)
{
struct platform_device *pd;
list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
if (platform_match(&pd->dev, &epdrv->pdrv->driver))
if (pd->id == id)
return pd;
return NULL;
}
/**
* early_platform_left
* @epdrv: early platform driver structure
* @id: return true if id or above exists
*/
static __init int early_platform_left(struct early_platform_driver *epdrv,
int id)
{
struct platform_device *pd;
list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
if (platform_match(&pd->dev, &epdrv->pdrv->driver))
if (pd->id >= id)
return 1;
return 0;
}
/**
* early_platform_driver_probe_id
* @class_str: string to identify early platform driver class
* @id: id to match against
* @nr_probe: number of platform devices to successfully probe before exiting
*/
static int __init early_platform_driver_probe_id(char *class_str,
int id,
int nr_probe)
{
struct early_platform_driver *epdrv;
struct platform_device *match;
int match_id;
int n = 0;
int left = 0;
list_for_each_entry(epdrv, &early_platform_driver_list, list) {
/* only use drivers matching our class_str */
if (strcmp(class_str, epdrv->class_str))
continue;
if (id == -2) {
match_id = epdrv->requested_id;
left = 1;
} else {
match_id = id;
left += early_platform_left(epdrv, id);
/* skip requested id */
switch (epdrv->requested_id) {
case EARLY_PLATFORM_ID_ERROR:
case EARLY_PLATFORM_ID_UNSET:
break;
default:
if (epdrv->requested_id == id)
match_id = EARLY_PLATFORM_ID_UNSET;
}
}
switch (match_id) {
case EARLY_PLATFORM_ID_ERROR:
pr_warning("%s: unable to parse %s parameter\n",
class_str, epdrv->pdrv->driver.name);
/* fall-through */
case EARLY_PLATFORM_ID_UNSET:
match = NULL;
break;
default:
match = early_platform_match(epdrv, match_id);
}
if (match) {
if (epdrv->pdrv->probe(match))
pr_warning("%s: unable to probe %s early.\n",
class_str, match->name);
else
n++;
}
if (n >= nr_probe)
break;
}
if (left)
return n;
else
return -ENODEV;
}
/**
* early_platform_driver_probe
* @class_str: string to identify early platform driver class
* @nr_probe: number of platform devices to successfully probe before exiting
* @user_only: only probe user specified early platform devices
*/
int __init early_platform_driver_probe(char *class_str,
int nr_probe,
int user_only)
{
int k, n, i;
n = 0;
for (i = -2; n < nr_probe; i++) {
k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
if (k < 0)
break;
n += k;
if (user_only)
break;
}
return n;
}
/**
* early_platform_cleanup - clean up early platform code
*/
void __init early_platform_cleanup(void)
{
struct platform_device *pd, *pd2;
/* clean up the devres list used to chain devices */
list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
dev.devres_head) {
list_del(&pd->dev.devres_head);
memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));
}
}