linux/drivers/base/platform.c
Kees Cook 36b2d7dd5a driver core: platform: Annotate struct irq_affinity_devres with __counted_by
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for
array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct
irq_affinity_devres.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: linux-hardening@vger.kernel.org
Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20231006201749.work.432-kees@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-07 18:13:09 +02:00

1535 lines
38 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* platform.c - platform 'pseudo' bus for legacy devices
*
* Copyright (c) 2002-3 Patrick Mochel
* Copyright (c) 2002-3 Open Source Development Labs
*
* Please see Documentation/driver-api/driver-model/platform.rst for more
* information.
*/
#include <linux/string.h>
#include <linux/platform_device.h>
#include <linux/of_device.h>
#include <linux/of_irq.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/dma-mapping.h>
#include <linux/memblock.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/pm_runtime.h>
#include <linux/pm_domain.h>
#include <linux/idr.h>
#include <linux/acpi.h>
#include <linux/clk/clk-conf.h>
#include <linux/limits.h>
#include <linux/property.h>
#include <linux/kmemleak.h>
#include <linux/types.h>
#include <linux/iommu.h>
#include <linux/dma-map-ops.h>
#include "base.h"
#include "power/power.h"
/* For automatically allocated device IDs */
static DEFINE_IDA(platform_devid_ida);
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
*
* Return: a pointer to the resource or NULL on failure.
*/
struct resource *platform_get_resource(struct platform_device *dev,
unsigned int type, unsigned int num)
{
u32 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);
struct resource *platform_get_mem_or_io(struct platform_device *dev,
unsigned int num)
{
u32 i;
for (i = 0; i < dev->num_resources; i++) {
struct resource *r = &dev->resource[i];
if ((resource_type(r) & (IORESOURCE_MEM|IORESOURCE_IO)) && num-- == 0)
return r;
}
return NULL;
}
EXPORT_SYMBOL_GPL(platform_get_mem_or_io);
#ifdef CONFIG_HAS_IOMEM
/**
* devm_platform_get_and_ioremap_resource - call devm_ioremap_resource() for a
* platform device and get resource
*
* @pdev: platform device to use both for memory resource lookup as well as
* resource management
* @index: resource index
* @res: optional output parameter to store a pointer to the obtained resource.
*
* Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
* on failure.
*/
void __iomem *
devm_platform_get_and_ioremap_resource(struct platform_device *pdev,
unsigned int index, struct resource **res)
{
struct resource *r;
r = platform_get_resource(pdev, IORESOURCE_MEM, index);
if (res)
*res = r;
return devm_ioremap_resource(&pdev->dev, r);
}
EXPORT_SYMBOL_GPL(devm_platform_get_and_ioremap_resource);
/**
* devm_platform_ioremap_resource - call devm_ioremap_resource() for a platform
* device
*
* @pdev: platform device to use both for memory resource lookup as well as
* resource management
* @index: resource index
*
* Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
* on failure.
*/
void __iomem *devm_platform_ioremap_resource(struct platform_device *pdev,
unsigned int index)
{
return devm_platform_get_and_ioremap_resource(pdev, index, NULL);
}
EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource);
/**
* devm_platform_ioremap_resource_byname - call devm_ioremap_resource for
* a platform device, retrieve the
* resource by name
*
* @pdev: platform device to use both for memory resource lookup as well as
* resource management
* @name: name of the resource
*
* Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
* on failure.
*/
void __iomem *
devm_platform_ioremap_resource_byname(struct platform_device *pdev,
const char *name)
{
struct resource *res;
res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
return devm_ioremap_resource(&pdev->dev, res);
}
EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource_byname);
#endif /* CONFIG_HAS_IOMEM */
/**
* platform_get_irq_optional - get an optional IRQ for a device
* @dev: platform device
* @num: IRQ number index
*
* Gets an IRQ for a platform device. Device drivers should check the return
* value for errors so as to not pass a negative integer value to the
* request_irq() APIs. This is the same as platform_get_irq(), except that it
* does not print an error message if an IRQ can not be obtained.
*
* For example::
*
* int irq = platform_get_irq_optional(pdev, 0);
* if (irq < 0)
* return irq;
*
* Return: non-zero IRQ number on success, negative error number on failure.
*/
int platform_get_irq_optional(struct platform_device *dev, unsigned int num)
{
int ret;
#ifdef CONFIG_SPARC
/* sparc does not have irqs represented as IORESOURCE_IRQ resources */
if (!dev || num >= dev->archdata.num_irqs)
goto out_not_found;
ret = dev->archdata.irqs[num];
goto out;
#else
struct fwnode_handle *fwnode = dev_fwnode(&dev->dev);
struct resource *r;
if (is_of_node(fwnode)) {
ret = of_irq_get(to_of_node(fwnode), num);
if (ret > 0 || ret == -EPROBE_DEFER)
goto out;
}
r = platform_get_resource(dev, IORESOURCE_IRQ, num);
if (is_acpi_device_node(fwnode)) {
if (r && r->flags & IORESOURCE_DISABLED) {
ret = acpi_irq_get(ACPI_HANDLE_FWNODE(fwnode), num, r);
if (ret)
goto out;
}
}
/*
* The resources may pass trigger flags to the irqs that need
* to be set up. It so happens that the trigger flags for
* IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
* settings.
*/
if (r && r->flags & IORESOURCE_BITS) {
struct irq_data *irqd;
irqd = irq_get_irq_data(r->start);
if (!irqd)
goto out_not_found;
irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);
}
if (r) {
ret = r->start;
goto out;
}
/*
* For the index 0 interrupt, allow falling back to GpioInt
* resources. While a device could have both Interrupt and GpioInt
* resources, making this fallback ambiguous, in many common cases
* the device will only expose one IRQ, and this fallback
* allows a common code path across either kind of resource.
*/
if (num == 0 && is_acpi_device_node(fwnode)) {
ret = acpi_dev_gpio_irq_get(to_acpi_device_node(fwnode), num);
/* Our callers expect -ENXIO for missing IRQs. */
if (ret >= 0 || ret == -EPROBE_DEFER)
goto out;
}
#endif
out_not_found:
ret = -ENXIO;
out:
if (WARN(!ret, "0 is an invalid IRQ number\n"))
return -EINVAL;
return ret;
}
EXPORT_SYMBOL_GPL(platform_get_irq_optional);
/**
* platform_get_irq - get an IRQ for a device
* @dev: platform device
* @num: IRQ number index
*
* Gets an IRQ for a platform device and prints an error message if finding the
* IRQ fails. Device drivers should check the return value for errors so as to
* not pass a negative integer value to the request_irq() APIs.
*
* For example::
*
* int irq = platform_get_irq(pdev, 0);
* if (irq < 0)
* return irq;
*
* Return: non-zero IRQ number on success, negative error number on failure.
*/
int platform_get_irq(struct platform_device *dev, unsigned int num)
{
int ret;
ret = platform_get_irq_optional(dev, num);
if (ret < 0)
return dev_err_probe(&dev->dev, ret,
"IRQ index %u not found\n", num);
return ret;
}
EXPORT_SYMBOL_GPL(platform_get_irq);
/**
* platform_irq_count - Count the number of IRQs a platform device uses
* @dev: platform device
*
* Return: Number of IRQs a platform device uses or EPROBE_DEFER
*/
int platform_irq_count(struct platform_device *dev)
{
int ret, nr = 0;
while ((ret = platform_get_irq_optional(dev, nr)) >= 0)
nr++;
if (ret == -EPROBE_DEFER)
return ret;
return nr;
}
EXPORT_SYMBOL_GPL(platform_irq_count);
struct irq_affinity_devres {
unsigned int count;
unsigned int irq[] __counted_by(count);
};
static void platform_disable_acpi_irq(struct platform_device *pdev, int index)
{
struct resource *r;
r = platform_get_resource(pdev, IORESOURCE_IRQ, index);
if (r)
irqresource_disabled(r, 0);
}
static void devm_platform_get_irqs_affinity_release(struct device *dev,
void *res)
{
struct irq_affinity_devres *ptr = res;
int i;
for (i = 0; i < ptr->count; i++) {
irq_dispose_mapping(ptr->irq[i]);
if (is_acpi_device_node(dev_fwnode(dev)))
platform_disable_acpi_irq(to_platform_device(dev), i);
}
}
/**
* devm_platform_get_irqs_affinity - devm method to get a set of IRQs for a
* device using an interrupt affinity descriptor
* @dev: platform device pointer
* @affd: affinity descriptor
* @minvec: minimum count of interrupt vectors
* @maxvec: maximum count of interrupt vectors
* @irqs: pointer holder for IRQ numbers
*
* Gets a set of IRQs for a platform device, and updates IRQ afffinty according
* to the passed affinity descriptor
*
* Return: Number of vectors on success, negative error number on failure.
*/
int devm_platform_get_irqs_affinity(struct platform_device *dev,
struct irq_affinity *affd,
unsigned int minvec,
unsigned int maxvec,
int **irqs)
{
struct irq_affinity_devres *ptr;
struct irq_affinity_desc *desc;
size_t size;
int i, ret, nvec;
if (!affd)
return -EPERM;
if (maxvec < minvec)
return -ERANGE;
nvec = platform_irq_count(dev);
if (nvec < 0)
return nvec;
if (nvec < minvec)
return -ENOSPC;
nvec = irq_calc_affinity_vectors(minvec, nvec, affd);
if (nvec < minvec)
return -ENOSPC;
if (nvec > maxvec)
nvec = maxvec;
size = sizeof(*ptr) + sizeof(unsigned int) * nvec;
ptr = devres_alloc(devm_platform_get_irqs_affinity_release, size,
GFP_KERNEL);
if (!ptr)
return -ENOMEM;
ptr->count = nvec;
for (i = 0; i < nvec; i++) {
int irq = platform_get_irq(dev, i);
if (irq < 0) {
ret = irq;
goto err_free_devres;
}
ptr->irq[i] = irq;
}
desc = irq_create_affinity_masks(nvec, affd);
if (!desc) {
ret = -ENOMEM;
goto err_free_devres;
}
for (i = 0; i < nvec; i++) {
ret = irq_update_affinity_desc(ptr->irq[i], &desc[i]);
if (ret) {
dev_err(&dev->dev, "failed to update irq%d affinity descriptor (%d)\n",
ptr->irq[i], ret);
goto err_free_desc;
}
}
devres_add(&dev->dev, ptr);
kfree(desc);
*irqs = ptr->irq;
return nvec;
err_free_desc:
kfree(desc);
err_free_devres:
devres_free(ptr);
return ret;
}
EXPORT_SYMBOL_GPL(devm_platform_get_irqs_affinity);
/**
* 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)
{
u32 i;
for (i = 0; i < dev->num_resources; i++) {
struct resource *r = &dev->resource[i];
if (unlikely(!r->name))
continue;
if (type == resource_type(r) && !strcmp(r->name, name))
return r;
}
return NULL;
}
EXPORT_SYMBOL_GPL(platform_get_resource_byname);
static int __platform_get_irq_byname(struct platform_device *dev,
const char *name)
{
struct resource *r;
int ret;
ret = fwnode_irq_get_byname(dev_fwnode(&dev->dev), name);
if (ret > 0 || ret == -EPROBE_DEFER)
return ret;
r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
if (r) {
if (WARN(!r->start, "0 is an invalid IRQ number\n"))
return -EINVAL;
return r->start;
}
return -ENXIO;
}
/**
* platform_get_irq_byname - get an IRQ for a device by name
* @dev: platform device
* @name: IRQ name
*
* Get an IRQ like platform_get_irq(), but then by name rather then by index.
*
* Return: non-zero IRQ number on success, negative error number on failure.
*/
int platform_get_irq_byname(struct platform_device *dev, const char *name)
{
int ret;
ret = __platform_get_irq_byname(dev, name);
if (ret < 0)
return dev_err_probe(&dev->dev, ret, "IRQ %s not found\n",
name);
return ret;
}
EXPORT_SYMBOL_GPL(platform_get_irq_byname);
/**
* platform_get_irq_byname_optional - get an optional IRQ for a device by name
* @dev: platform device
* @name: IRQ name
*
* Get an optional IRQ by name like platform_get_irq_byname(). Except that it
* does not print an error message if an IRQ can not be obtained.
*
* Return: non-zero IRQ number on success, negative error number on failure.
*/
int platform_get_irq_byname_optional(struct platform_device *dev,
const char *name)
{
return __platform_get_irq_byname(dev, name);
}
EXPORT_SYMBOL_GPL(platform_get_irq_byname_optional);
/**
* platform_add_devices - add a numbers of platform devices
* @devs: array of platform devices to add
* @num: number of platform devices in array
*
* Return: 0 on success, negative error number on failure.
*/
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[];
};
/*
* Set up default DMA mask for platform devices if the they weren't
* previously set by the architecture / DT.
*/
static void setup_pdev_dma_masks(struct platform_device *pdev)
{
pdev->dev.dma_parms = &pdev->dma_parms;
if (!pdev->dev.coherent_dma_mask)
pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
if (!pdev->dev.dma_mask) {
pdev->platform_dma_mask = DMA_BIT_MASK(32);
pdev->dev.dma_mask = &pdev->platform_dma_mask;
}
};
/**
* platform_device_put - destroy a platform device
* @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 (!IS_ERR_OR_NULL(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);
of_node_put(pa->pdev.dev.of_node);
kfree(pa->pdev.dev.platform_data);
kfree(pa->pdev.mfd_cell);
kfree(pa->pdev.resource);
kfree(pa->pdev.driver_override);
kfree(pa);
}
/**
* platform_device_alloc - create a platform device
* @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(*pa) + strlen(name) + 1, 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;
setup_pdev_dma_masks(&pa->pdev);
}
return pa ? &pa->pdev : NULL;
}
EXPORT_SYMBOL_GPL(platform_device_alloc);
/**
* platform_device_add_resources - add resources to a platform device
* @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,
const struct resource *res, unsigned int num)
{
struct resource *r = NULL;
if (res) {
r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
if (!r)
return -ENOMEM;
}
kfree(pdev->resource);
pdev->resource = r;
pdev->num_resources = num;
return 0;
}
EXPORT_SYMBOL_GPL(platform_device_add_resources);
/**
* platform_device_add_data - add platform-specific data to a platform device
* @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 = NULL;
if (data) {
d = kmemdup(data, size, GFP_KERNEL);
if (!d)
return -ENOMEM;
}
kfree(pdev->dev.platform_data);
pdev->dev.platform_data = d;
return 0;
}
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)
{
struct device *dev = &pdev->dev;
u32 i;
int ret;
if (!dev->parent)
dev->parent = &platform_bus;
dev->bus = &platform_bus_type;
switch (pdev->id) {
default:
dev_set_name(dev, "%s.%d", pdev->name, pdev->id);
break;
case PLATFORM_DEVID_NONE:
dev_set_name(dev, "%s", pdev->name);
break;
case PLATFORM_DEVID_AUTO:
/*
* Automatically allocated device ID. We mark it as such so
* that we remember it must be freed, and we append a suffix
* to avoid namespace collision with explicit IDs.
*/
ret = ida_alloc(&platform_devid_ida, GFP_KERNEL);
if (ret < 0)
return ret;
pdev->id = ret;
pdev->id_auto = true;
dev_set_name(dev, "%s.%d.auto", pdev->name, pdev->id);
break;
}
for (i = 0; i < pdev->num_resources; i++) {
struct resource *p, *r = &pdev->resource[i];
if (r->name == NULL)
r->name = dev_name(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) {
ret = insert_resource(p, r);
if (ret) {
dev_err(dev, "failed to claim resource %d: %pR\n", i, r);
goto failed;
}
}
}
pr_debug("Registering platform device '%s'. Parent at %s\n", dev_name(dev),
dev_name(dev->parent));
ret = device_add(dev);
if (ret)
goto failed;
return 0;
failed:
if (pdev->id_auto) {
ida_free(&platform_devid_ida, pdev->id);
pdev->id = PLATFORM_DEVID_AUTO;
}
while (i--) {
struct resource *r = &pdev->resource[i];
if (r->parent)
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)
{
u32 i;
if (!IS_ERR_OR_NULL(pdev)) {
device_del(&pdev->dev);
if (pdev->id_auto) {
ida_free(&platform_devid_ida, pdev->id);
pdev->id = PLATFORM_DEVID_AUTO;
}
for (i = 0; i < pdev->num_resources; i++) {
struct resource *r = &pdev->resource[i];
if (r->parent)
release_resource(r);
}
}
}
EXPORT_SYMBOL_GPL(platform_device_del);
/**
* platform_device_register - add a platform-level device
* @pdev: platform device we're adding
*
* NOTE: _Never_ directly free @pdev after calling this function, even if it
* returned an error! Always use platform_device_put() to give up the
* reference initialised in this function instead.
*/
int platform_device_register(struct platform_device *pdev)
{
device_initialize(&pdev->dev);
setup_pdev_dma_masks(pdev);
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_full - add a platform-level device with
* resources and platform-specific data
*
* @pdevinfo: data used to create device
*
* Returns &struct platform_device pointer on success, or ERR_PTR() on error.
*/
struct platform_device *platform_device_register_full(
const struct platform_device_info *pdevinfo)
{
int ret;
struct platform_device *pdev;
pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
if (!pdev)
return ERR_PTR(-ENOMEM);
pdev->dev.parent = pdevinfo->parent;
pdev->dev.fwnode = pdevinfo->fwnode;
pdev->dev.of_node = of_node_get(to_of_node(pdev->dev.fwnode));
pdev->dev.of_node_reused = pdevinfo->of_node_reused;
if (pdevinfo->dma_mask) {
pdev->platform_dma_mask = pdevinfo->dma_mask;
pdev->dev.dma_mask = &pdev->platform_dma_mask;
pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
}
ret = platform_device_add_resources(pdev,
pdevinfo->res, pdevinfo->num_res);
if (ret)
goto err;
ret = platform_device_add_data(pdev,
pdevinfo->data, pdevinfo->size_data);
if (ret)
goto err;
if (pdevinfo->properties) {
ret = device_create_managed_software_node(&pdev->dev,
pdevinfo->properties, NULL);
if (ret)
goto err;
}
ret = platform_device_add(pdev);
if (ret) {
err:
ACPI_COMPANION_SET(&pdev->dev, NULL);
platform_device_put(pdev);
return ERR_PTR(ret);
}
return pdev;
}
EXPORT_SYMBOL_GPL(platform_device_register_full);
/**
* __platform_driver_register - register a driver for platform-level devices
* @drv: platform driver structure
* @owner: owning module/driver
*/
int __platform_driver_register(struct platform_driver *drv,
struct module *owner)
{
drv->driver.owner = owner;
drv->driver.bus = &platform_bus_type;
return driver_register(&drv->driver);
}
EXPORT_SYMBOL_GPL(__platform_driver_register);
/**
* platform_driver_unregister - unregister a driver for platform-level devices
* @drv: platform driver structure
*/
void platform_driver_unregister(struct platform_driver *drv)
{
driver_unregister(&drv->driver);
}
EXPORT_SYMBOL_GPL(platform_driver_unregister);
static int platform_probe_fail(struct platform_device *pdev)
{
return -ENXIO;
}
static int is_bound_to_driver(struct device *dev, void *driver)
{
if (dev->driver == driver)
return 1;
return 0;
}
/**
* __platform_driver_probe - register driver for non-hotpluggable device
* @drv: platform driver structure
* @probe: the driver probe routine, probably from an __init section
* @module: module which will be the owner of the driver
*
* 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.
*
* Note that this is incompatible with deferred probing.
*
* 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 *), struct module *module)
{
int retval;
if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) {
pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
drv->driver.name, __func__);
return -EINVAL;
}
/*
* We have to run our probes synchronously because we check if
* we find any devices to bind to and exit with error if there
* are any.
*/
drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS;
/*
* Prevent driver from requesting probe deferral to avoid further
* futile probe attempts.
*/
drv->prevent_deferred_probe = true;
/* make sure driver won't have bind/unbind attributes */
drv->driver.suppress_bind_attrs = true;
/* temporary section violation during probe() */
drv->probe = probe;
retval = __platform_driver_register(drv, module);
if (retval)
return retval;
/* Force all new probes of this driver to fail */
drv->probe = platform_probe_fail;
/* Walk all platform devices and see if any actually bound to this driver.
* If not, return an error as the device should have done so by now.
*/
if (!bus_for_each_dev(&platform_bus_type, NULL, &drv->driver, is_bound_to_driver)) {
retval = -ENODEV;
platform_driver_unregister(drv);
}
return retval;
}
EXPORT_SYMBOL_GPL(__platform_driver_probe);
/**
* __platform_create_bundle - register driver and create corresponding device
* @driver: platform driver structure
* @probe: the driver probe routine, probably from an __init section
* @res: set of resources that needs to be allocated for the device
* @n_res: number of resources
* @data: platform specific data for this platform device
* @size: size of platform specific data
* @module: module which will be the owner of the driver
*
* Use this in legacy-style modules that probe hardware directly and
* register a single platform device and corresponding platform driver.
*
* Returns &struct platform_device pointer on success, or ERR_PTR() on error.
*/
struct platform_device * __init_or_module __platform_create_bundle(
struct platform_driver *driver,
int (*probe)(struct platform_device *),
struct resource *res, unsigned int n_res,
const void *data, size_t size, struct module *module)
{
struct platform_device *pdev;
int error;
pdev = platform_device_alloc(driver->driver.name, -1);
if (!pdev) {
error = -ENOMEM;
goto err_out;
}
error = platform_device_add_resources(pdev, res, n_res);
if (error)
goto err_pdev_put;
error = platform_device_add_data(pdev, data, size);
if (error)
goto err_pdev_put;
error = platform_device_add(pdev);
if (error)
goto err_pdev_put;
error = __platform_driver_probe(driver, probe, module);
if (error)
goto err_pdev_del;
return pdev;
err_pdev_del:
platform_device_del(pdev);
err_pdev_put:
platform_device_put(pdev);
err_out:
return ERR_PTR(error);
}
EXPORT_SYMBOL_GPL(__platform_create_bundle);
/**
* __platform_register_drivers - register an array of platform drivers
* @drivers: an array of drivers to register
* @count: the number of drivers to register
* @owner: module owning the drivers
*
* Registers platform drivers specified by an array. On failure to register a
* driver, all previously registered drivers will be unregistered. Callers of
* this API should use platform_unregister_drivers() to unregister drivers in
* the reverse order.
*
* Returns: 0 on success or a negative error code on failure.
*/
int __platform_register_drivers(struct platform_driver * const *drivers,
unsigned int count, struct module *owner)
{
unsigned int i;
int err;
for (i = 0; i < count; i++) {
pr_debug("registering platform driver %ps\n", drivers[i]);
err = __platform_driver_register(drivers[i], owner);
if (err < 0) {
pr_err("failed to register platform driver %ps: %d\n",
drivers[i], err);
goto error;
}
}
return 0;
error:
while (i--) {
pr_debug("unregistering platform driver %ps\n", drivers[i]);
platform_driver_unregister(drivers[i]);
}
return err;
}
EXPORT_SYMBOL_GPL(__platform_register_drivers);
/**
* platform_unregister_drivers - unregister an array of platform drivers
* @drivers: an array of drivers to unregister
* @count: the number of drivers to unregister
*
* Unregisters platform drivers specified by an array. This is typically used
* to complement an earlier call to platform_register_drivers(). Drivers are
* unregistered in the reverse order in which they were registered.
*/
void platform_unregister_drivers(struct platform_driver * const *drivers,
unsigned int count)
{
while (count--) {
pr_debug("unregistering platform driver %ps\n", drivers[count]);
platform_driver_unregister(drivers[count]);
}
}
EXPORT_SYMBOL_GPL(platform_unregister_drivers);
static const struct platform_device_id *platform_match_id(
const 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;
}
#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;
}
#endif /* CONFIG_PM_SLEEP */
#ifdef CONFIG_SUSPEND
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;
}
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;
}
#endif /* CONFIG_SUSPEND */
#ifdef CONFIG_HIBERNATE_CALLBACKS
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;
}
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;
}
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;
}
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;
}
#endif /* CONFIG_HIBERNATE_CALLBACKS */
/* 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 *attr, char *buf)
{
struct platform_device *pdev = to_platform_device(dev);
int len;
len = of_device_modalias(dev, buf, PAGE_SIZE);
if (len != -ENODEV)
return len;
len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1);
if (len != -ENODEV)
return len;
return sysfs_emit(buf, "platform:%s\n", pdev->name);
}
static DEVICE_ATTR_RO(modalias);
static ssize_t numa_node_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sysfs_emit(buf, "%d\n", dev_to_node(dev));
}
static DEVICE_ATTR_RO(numa_node);
static ssize_t driver_override_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct platform_device *pdev = to_platform_device(dev);
ssize_t len;
device_lock(dev);
len = sysfs_emit(buf, "%s\n", pdev->driver_override);
device_unlock(dev);
return len;
}
static ssize_t driver_override_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct platform_device *pdev = to_platform_device(dev);
int ret;
ret = driver_set_override(dev, &pdev->driver_override, buf, count);
if (ret)
return ret;
return count;
}
static DEVICE_ATTR_RW(driver_override);
static struct attribute *platform_dev_attrs[] = {
&dev_attr_modalias.attr,
&dev_attr_numa_node.attr,
&dev_attr_driver_override.attr,
NULL,
};
static umode_t platform_dev_attrs_visible(struct kobject *kobj, struct attribute *a,
int n)
{
struct device *dev = container_of(kobj, typeof(*dev), kobj);
if (a == &dev_attr_numa_node.attr &&
dev_to_node(dev) == NUMA_NO_NODE)
return 0;
return a->mode;
}
static const struct attribute_group platform_dev_group = {
.attrs = platform_dev_attrs,
.is_visible = platform_dev_attrs_visible,
};
__ATTRIBUTE_GROUPS(platform_dev);
/**
* 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);
/* When driver_override is set, only bind to the matching driver */
if (pdev->driver_override)
return !strcmp(pdev->driver_override, drv->name);
/* Attempt an OF style match first */
if (of_driver_match_device(dev, drv))
return 1;
/* Then try ACPI style match */
if (acpi_driver_match_device(dev, drv))
return 1;
/* Then try to match against the id table */
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);
}
static int platform_uevent(const struct device *dev, struct kobj_uevent_env *env)
{
const struct platform_device *pdev = to_platform_device(dev);
int rc;
/* Some devices have extra OF data and an OF-style MODALIAS */
rc = of_device_uevent_modalias(dev, env);
if (rc != -ENODEV)
return rc;
rc = acpi_device_uevent_modalias(dev, env);
if (rc != -ENODEV)
return rc;
add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
pdev->name);
return 0;
}
static int platform_probe(struct device *_dev)
{
struct platform_driver *drv = to_platform_driver(_dev->driver);
struct platform_device *dev = to_platform_device(_dev);
int ret;
/*
* A driver registered using platform_driver_probe() cannot be bound
* again later because the probe function usually lives in __init code
* and so is gone. For these drivers .probe is set to
* platform_probe_fail in __platform_driver_probe(). Don't even prepare
* clocks and PM domains for these to match the traditional behaviour.
*/
if (unlikely(drv->probe == platform_probe_fail))
return -ENXIO;
ret = of_clk_set_defaults(_dev->of_node, false);
if (ret < 0)
return ret;
ret = dev_pm_domain_attach(_dev, true);
if (ret)
goto out;
if (drv->probe) {
ret = drv->probe(dev);
if (ret)
dev_pm_domain_detach(_dev, true);
}
out:
if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
dev_warn(_dev, "probe deferral not supported\n");
ret = -ENXIO;
}
return ret;
}
static void platform_remove(struct device *_dev)
{
struct platform_driver *drv = to_platform_driver(_dev->driver);
struct platform_device *dev = to_platform_device(_dev);
if (drv->remove_new) {
drv->remove_new(dev);
} else if (drv->remove) {
int ret = drv->remove(dev);
if (ret)
dev_warn(_dev, "remove callback returned a non-zero value. This will be ignored.\n");
}
dev_pm_domain_detach(_dev, true);
}
static void platform_shutdown(struct device *_dev)
{
struct platform_device *dev = to_platform_device(_dev);
struct platform_driver *drv;
if (!_dev->driver)
return;
drv = to_platform_driver(_dev->driver);
if (drv->shutdown)
drv->shutdown(dev);
}
static int platform_dma_configure(struct device *dev)
{
struct platform_driver *drv = to_platform_driver(dev->driver);
struct fwnode_handle *fwnode = dev_fwnode(dev);
enum dev_dma_attr attr;
int ret = 0;
if (is_of_node(fwnode)) {
ret = of_dma_configure(dev, to_of_node(fwnode), true);
} else if (is_acpi_device_node(fwnode)) {
attr = acpi_get_dma_attr(to_acpi_device_node(fwnode));
ret = acpi_dma_configure(dev, attr);
}
if (ret || drv->driver_managed_dma)
return ret;
ret = iommu_device_use_default_domain(dev);
if (ret)
arch_teardown_dma_ops(dev);
return ret;
}
static void platform_dma_cleanup(struct device *dev)
{
struct platform_driver *drv = to_platform_driver(dev->driver);
if (!drv->driver_managed_dma)
iommu_device_unuse_default_domain(dev);
}
static const struct dev_pm_ops platform_dev_pm_ops = {
SET_RUNTIME_PM_OPS(pm_generic_runtime_suspend, pm_generic_runtime_resume, NULL)
USE_PLATFORM_PM_SLEEP_OPS
};
struct bus_type platform_bus_type = {
.name = "platform",
.dev_groups = platform_dev_groups,
.match = platform_match,
.uevent = platform_uevent,
.probe = platform_probe,
.remove = platform_remove,
.shutdown = platform_shutdown,
.dma_configure = platform_dma_configure,
.dma_cleanup = platform_dma_cleanup,
.pm = &platform_dev_pm_ops,
};
EXPORT_SYMBOL_GPL(platform_bus_type);
static inline int __platform_match(struct device *dev, const void *drv)
{
return platform_match(dev, (struct device_driver *)drv);
}
/**
* platform_find_device_by_driver - Find a platform device with a given
* driver.
* @start: The device to start the search from.
* @drv: The device driver to look for.
*/
struct device *platform_find_device_by_driver(struct device *start,
const struct device_driver *drv)
{
return bus_find_device(&platform_bus_type, start, drv,
__platform_match);
}
EXPORT_SYMBOL_GPL(platform_find_device_by_driver);
void __weak __init early_platform_cleanup(void) { }
int __init platform_bus_init(void)
{
int error;
early_platform_cleanup();
error = device_register(&platform_bus);
if (error) {
put_device(&platform_bus);
return error;
}
error = bus_register(&platform_bus_type);
if (error)
device_unregister(&platform_bus);
return error;
}