linux-next/include/linux/mcb.h
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

133 lines
3.6 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* MEN Chameleon Bus.
*
* Copyright (C) 2014 MEN Mikroelektronik GmbH (www.men.de)
* Author: Johannes Thumshirn <johannes.thumshirn@men.de>
*/
#ifndef _LINUX_MCB_H
#define _LINUX_MCB_H
#include <linux/mod_devicetable.h>
#include <linux/device.h>
#include <linux/irqreturn.h>
#define CHAMELEON_FILENAME_LEN 12
struct mcb_driver;
struct mcb_device;
/**
* struct mcb_bus - MEN Chameleon Bus
*
* @dev: bus device
* @carrier: pointer to carrier device
* @bus_nr: mcb bus number
* @get_irq: callback to get IRQ number
* @revision: the FPGA's revision number
* @model: the FPGA's model number
* @filename: the FPGA's name
*/
struct mcb_bus {
struct device dev;
struct device *carrier;
int bus_nr;
u8 revision;
char model;
u8 minor;
char name[CHAMELEON_FILENAME_LEN + 1];
int (*get_irq)(struct mcb_device *dev);
};
static inline struct mcb_bus *to_mcb_bus(struct device *dev)
{
return container_of(dev, struct mcb_bus, dev);
}
/**
* struct mcb_device - MEN Chameleon Bus device
*
* @dev: device in kernel representation
* @bus: mcb bus the device is plugged to
* @is_added: flag to check if device is added to bus
* @driver: associated mcb_driver
* @id: mcb device id
* @inst: instance in Chameleon table
* @group: group in Chameleon table
* @var: variant in Chameleon table
* @bar: BAR in Chameleon table
* @rev: revision in Chameleon table
* @irq: IRQ resource
* @memory: memory resource
*/
struct mcb_device {
struct device dev;
struct mcb_bus *bus;
struct mcb_driver *driver;
u16 id;
int inst;
int group;
int var;
int bar;
int rev;
struct resource irq;
struct resource mem;
struct device *dma_dev;
};
#define to_mcb_device(__dev) container_of_const(__dev, struct mcb_device, dev)
/**
* struct mcb_driver - MEN Chameleon Bus device driver
*
* @driver: device_driver
* @id_table: mcb id table
* @probe: probe callback
* @remove: remove callback
* @shutdown: shutdown callback
*/
struct mcb_driver {
struct device_driver driver;
const struct mcb_device_id *id_table;
int (*probe)(struct mcb_device *mdev, const struct mcb_device_id *id);
void (*remove)(struct mcb_device *mdev);
void (*shutdown)(struct mcb_device *mdev);
};
#define to_mcb_driver(__drv) container_of_const(__drv, struct mcb_driver, driver)
static inline void *mcb_get_drvdata(struct mcb_device *dev)
{
return dev_get_drvdata(&dev->dev);
}
static inline void mcb_set_drvdata(struct mcb_device *dev, void *data)
{
dev_set_drvdata(&dev->dev, data);
}
extern int __must_check __mcb_register_driver(struct mcb_driver *drv,
struct module *owner,
const char *mod_name);
#define mcb_register_driver(driver) \
__mcb_register_driver(driver, THIS_MODULE, KBUILD_MODNAME)
extern void mcb_unregister_driver(struct mcb_driver *driver);
#define module_mcb_driver(__mcb_driver) \
module_driver(__mcb_driver, mcb_register_driver, mcb_unregister_driver)
extern void mcb_bus_add_devices(const struct mcb_bus *bus);
extern int mcb_device_register(struct mcb_bus *bus, struct mcb_device *dev);
extern struct mcb_bus *mcb_alloc_bus(struct device *carrier);
extern struct mcb_bus *mcb_bus_get(struct mcb_bus *bus);
extern void mcb_bus_put(struct mcb_bus *bus);
extern struct mcb_device *mcb_alloc_dev(struct mcb_bus *bus);
extern void mcb_free_dev(struct mcb_device *dev);
extern void mcb_release_bus(struct mcb_bus *bus);
extern struct resource *mcb_request_mem(struct mcb_device *dev,
const char *name);
extern void mcb_release_mem(struct resource *mem);
extern int mcb_get_irq(struct mcb_device *dev);
extern struct resource *mcb_get_resource(struct mcb_device *dev,
unsigned int type);
#endif /* _LINUX_MCB_H */