linux-stable/drivers/mmc/core/sdio_bus.c
Greg Kroah-Hartman d69d804845 driver core: have match() callback in struct bus_type take a const *
In the match() callback, the struct device_driver * should not be
changed, so change the function callback to be a const *.  This is one
step of many towards making the driver core safe to have struct
device_driver in read-only memory.

Because the match() callback is in all busses, all busses are modified
to handle this properly.  This does entail switching some container_of()
calls to container_of_const() to properly handle the constant *.

For some busses, like PCI and USB and HV, the const * is cast away in
the match callback as those busses do want to modify those structures at
this point in time (they have a local lock in the driver structure.)
That will have to be changed in the future if they wish to have their
struct device * in read-only-memory.

Cc: Rafael J. Wysocki <rafael@kernel.org>
Reviewed-by: Alex Elder <elder@kernel.org>
Acked-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-03 15:16:54 +02:00

402 lines
9.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* linux/drivers/mmc/core/sdio_bus.c
*
* Copyright 2007 Pierre Ossman
*
* SDIO function driver model
*/
#include <linux/device.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/slab.h>
#include <linux/pm_runtime.h>
#include <linux/pm_domain.h>
#include <linux/acpi.h>
#include <linux/sysfs.h>
#include <linux/mmc/card.h>
#include <linux/mmc/host.h>
#include <linux/mmc/sdio_func.h>
#include <linux/of.h>
#include "core.h"
#include "card.h"
#include "sdio_cis.h"
#include "sdio_bus.h"
#define to_sdio_driver(d) container_of_const(d, struct sdio_driver, drv)
/* show configuration fields */
#define sdio_config_attr(field, format_string, args...) \
static ssize_t \
field##_show(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
struct sdio_func *func; \
\
func = dev_to_sdio_func (dev); \
return sysfs_emit(buf, format_string, args); \
} \
static DEVICE_ATTR_RO(field)
sdio_config_attr(class, "0x%02x\n", func->class);
sdio_config_attr(vendor, "0x%04x\n", func->vendor);
sdio_config_attr(device, "0x%04x\n", func->device);
sdio_config_attr(revision, "%u.%u\n", func->major_rev, func->minor_rev);
sdio_config_attr(modalias, "sdio:c%02Xv%04Xd%04X\n", func->class, func->vendor, func->device);
#define sdio_info_attr(num) \
static ssize_t info##num##_show(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
struct sdio_func *func = dev_to_sdio_func(dev); \
\
if (num > func->num_info) \
return -ENODATA; \
if (!func->info[num - 1][0]) \
return 0; \
return sysfs_emit(buf, "%s\n", func->info[num - 1]); \
} \
static DEVICE_ATTR_RO(info##num)
sdio_info_attr(1);
sdio_info_attr(2);
sdio_info_attr(3);
sdio_info_attr(4);
static struct attribute *sdio_dev_attrs[] = {
&dev_attr_class.attr,
&dev_attr_vendor.attr,
&dev_attr_device.attr,
&dev_attr_revision.attr,
&dev_attr_info1.attr,
&dev_attr_info2.attr,
&dev_attr_info3.attr,
&dev_attr_info4.attr,
&dev_attr_modalias.attr,
NULL,
};
ATTRIBUTE_GROUPS(sdio_dev);
static const struct sdio_device_id *sdio_match_one(struct sdio_func *func,
const struct sdio_device_id *id)
{
if (id->class != (__u8)SDIO_ANY_ID && id->class != func->class)
return NULL;
if (id->vendor != (__u16)SDIO_ANY_ID && id->vendor != func->vendor)
return NULL;
if (id->device != (__u16)SDIO_ANY_ID && id->device != func->device)
return NULL;
return id;
}
static const struct sdio_device_id *sdio_match_device(struct sdio_func *func,
const struct sdio_driver *sdrv)
{
const struct sdio_device_id *ids;
ids = sdrv->id_table;
if (ids) {
while (ids->class || ids->vendor || ids->device) {
if (sdio_match_one(func, ids))
return ids;
ids++;
}
}
return NULL;
}
static int sdio_bus_match(struct device *dev, const struct device_driver *drv)
{
struct sdio_func *func = dev_to_sdio_func(dev);
const struct sdio_driver *sdrv = to_sdio_driver(drv);
if (sdio_match_device(func, sdrv))
return 1;
return 0;
}
static int
sdio_bus_uevent(const struct device *dev, struct kobj_uevent_env *env)
{
const struct sdio_func *func = dev_to_sdio_func(dev);
unsigned int i;
if (add_uevent_var(env,
"SDIO_CLASS=%02X", func->class))
return -ENOMEM;
if (add_uevent_var(env,
"SDIO_ID=%04X:%04X", func->vendor, func->device))
return -ENOMEM;
if (add_uevent_var(env,
"SDIO_REVISION=%u.%u", func->major_rev, func->minor_rev))
return -ENOMEM;
for (i = 0; i < func->num_info; i++) {
if (add_uevent_var(env, "SDIO_INFO%u=%s", i+1, func->info[i]))
return -ENOMEM;
}
if (add_uevent_var(env,
"MODALIAS=sdio:c%02Xv%04Xd%04X",
func->class, func->vendor, func->device))
return -ENOMEM;
return 0;
}
static int sdio_bus_probe(struct device *dev)
{
struct sdio_driver *drv = to_sdio_driver(dev->driver);
struct sdio_func *func = dev_to_sdio_func(dev);
const struct sdio_device_id *id;
int ret;
id = sdio_match_device(func, drv);
if (!id)
return -ENODEV;
ret = dev_pm_domain_attach(dev, false);
if (ret)
return ret;
atomic_inc(&func->card->sdio_funcs_probed);
/* Unbound SDIO functions are always suspended.
* During probe, the function is set active and the usage count
* is incremented. If the driver supports runtime PM,
* it should call pm_runtime_put_noidle() in its probe routine and
* pm_runtime_get_noresume() in its remove routine.
*/
if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD) {
ret = pm_runtime_get_sync(dev);
if (ret < 0)
goto disable_runtimepm;
}
/* Set the default block size so the driver is sure it's something
* sensible. */
sdio_claim_host(func);
if (mmc_card_removed(func->card))
ret = -ENOMEDIUM;
else
ret = sdio_set_block_size(func, 0);
sdio_release_host(func);
if (ret)
goto disable_runtimepm;
ret = drv->probe(func, id);
if (ret)
goto disable_runtimepm;
return 0;
disable_runtimepm:
atomic_dec(&func->card->sdio_funcs_probed);
if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD)
pm_runtime_put_noidle(dev);
dev_pm_domain_detach(dev, false);
return ret;
}
static void sdio_bus_remove(struct device *dev)
{
struct sdio_driver *drv = to_sdio_driver(dev->driver);
struct sdio_func *func = dev_to_sdio_func(dev);
/* Make sure card is powered before invoking ->remove() */
if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD)
pm_runtime_get_sync(dev);
drv->remove(func);
atomic_dec(&func->card->sdio_funcs_probed);
if (func->irq_handler) {
pr_warn("WARNING: driver %s did not remove its interrupt handler!\n",
drv->name);
sdio_claim_host(func);
sdio_release_irq(func);
sdio_release_host(func);
}
/* First, undo the increment made directly above */
if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD)
pm_runtime_put_noidle(dev);
/* Then undo the runtime PM settings in sdio_bus_probe() */
if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD)
pm_runtime_put_sync(dev);
dev_pm_domain_detach(dev, false);
}
static const struct dev_pm_ops sdio_bus_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(pm_generic_suspend, pm_generic_resume)
SET_RUNTIME_PM_OPS(
pm_generic_runtime_suspend,
pm_generic_runtime_resume,
NULL
)
};
static const struct bus_type sdio_bus_type = {
.name = "sdio",
.dev_groups = sdio_dev_groups,
.match = sdio_bus_match,
.uevent = sdio_bus_uevent,
.probe = sdio_bus_probe,
.remove = sdio_bus_remove,
.pm = &sdio_bus_pm_ops,
};
int sdio_register_bus(void)
{
return bus_register(&sdio_bus_type);
}
void sdio_unregister_bus(void)
{
bus_unregister(&sdio_bus_type);
}
/**
* __sdio_register_driver - register a function driver
* @drv: SDIO function driver
* @owner: owning module/driver
*/
int __sdio_register_driver(struct sdio_driver *drv, struct module *owner)
{
drv->drv.name = drv->name;
drv->drv.bus = &sdio_bus_type;
drv->drv.owner = owner;
return driver_register(&drv->drv);
}
EXPORT_SYMBOL_GPL(__sdio_register_driver);
/**
* sdio_unregister_driver - unregister a function driver
* @drv: SDIO function driver
*/
void sdio_unregister_driver(struct sdio_driver *drv)
{
drv->drv.bus = &sdio_bus_type;
driver_unregister(&drv->drv);
}
EXPORT_SYMBOL_GPL(sdio_unregister_driver);
static void sdio_release_func(struct device *dev)
{
struct sdio_func *func = dev_to_sdio_func(dev);
if (!(func->card->quirks & MMC_QUIRK_NONSTD_SDIO))
sdio_free_func_cis(func);
/*
* We have now removed the link to the tuples in the
* card structure, so remove the reference.
*/
put_device(&func->card->dev);
kfree(func->info);
kfree(func->tmpbuf);
kfree(func);
}
/*
* Allocate and initialise a new SDIO function structure.
*/
struct sdio_func *sdio_alloc_func(struct mmc_card *card)
{
struct sdio_func *func;
func = kzalloc(sizeof(struct sdio_func), GFP_KERNEL);
if (!func)
return ERR_PTR(-ENOMEM);
/*
* allocate buffer separately to make sure it's properly aligned for
* DMA usage (incl. 64 bit DMA)
*/
func->tmpbuf = kmalloc(4, GFP_KERNEL);
if (!func->tmpbuf) {
kfree(func);
return ERR_PTR(-ENOMEM);
}
func->card = card;
device_initialize(&func->dev);
/*
* We may link to tuples in the card structure,
* we need make sure we have a reference to it.
*/
get_device(&func->card->dev);
func->dev.parent = &card->dev;
func->dev.bus = &sdio_bus_type;
func->dev.release = sdio_release_func;
return func;
}
#ifdef CONFIG_ACPI
static void sdio_acpi_set_handle(struct sdio_func *func)
{
struct mmc_host *host = func->card->host;
u64 addr = ((u64)host->slotno << 16) | func->num;
acpi_preset_companion(&func->dev, ACPI_COMPANION(host->parent), addr);
}
#else
static inline void sdio_acpi_set_handle(struct sdio_func *func) {}
#endif
static void sdio_set_of_node(struct sdio_func *func)
{
struct mmc_host *host = func->card->host;
func->dev.of_node = mmc_of_find_child_device(host, func->num);
}
/*
* Register a new SDIO function with the driver model.
*/
int sdio_add_func(struct sdio_func *func)
{
int ret;
dev_set_name(&func->dev, "%s:%d", mmc_card_id(func->card), func->num);
sdio_set_of_node(func);
sdio_acpi_set_handle(func);
device_enable_async_suspend(&func->dev);
ret = device_add(&func->dev);
if (ret == 0)
sdio_func_set_present(func);
return ret;
}
/*
* Unregister a SDIO function with the driver model, and
* (eventually) free it.
* This function can be called through error paths where sdio_add_func() was
* never executed (because a failure occurred at an earlier point).
*/
void sdio_remove_func(struct sdio_func *func)
{
if (sdio_func_present(func))
device_del(&func->dev);
of_node_put(func->dev.of_node);
put_device(&func->dev);
}