mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-29 15:43:59 +08:00
e0c24bddf0
Once we call fsi_master_unregister, the core will put_device, potentially freeing the hub master. This change adds a comment explaining the lifetime of an allocated fsi_master. We then add a reference from the driver to the hub master, so it stays around until we've finished ->remove(). Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Tested-by: Christopher Bostic <cbostic@linux.vnet.ibm.com> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
61 lines
2.2 KiB
C
61 lines
2.2 KiB
C
/*
|
|
* FSI master definitions. These comprise the core <--> master interface,
|
|
* to allow the core to interact with the (hardware-specific) masters.
|
|
*
|
|
* Copyright (C) IBM Corporation 2016
|
|
*
|
|
* 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.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*/
|
|
|
|
#ifndef DRIVERS_FSI_MASTER_H
|
|
#define DRIVERS_FSI_MASTER_H
|
|
|
|
#include <linux/device.h>
|
|
|
|
#define FSI_MASTER_FLAG_SWCLOCK 0x1
|
|
|
|
struct fsi_master {
|
|
struct device dev;
|
|
int idx;
|
|
int n_links;
|
|
int flags;
|
|
int (*read)(struct fsi_master *, int link, uint8_t id,
|
|
uint32_t addr, void *val, size_t size);
|
|
int (*write)(struct fsi_master *, int link, uint8_t id,
|
|
uint32_t addr, const void *val, size_t size);
|
|
int (*term)(struct fsi_master *, int link, uint8_t id);
|
|
int (*send_break)(struct fsi_master *, int link);
|
|
int (*link_enable)(struct fsi_master *, int link);
|
|
};
|
|
|
|
#define dev_to_fsi_master(d) container_of(d, struct fsi_master, dev)
|
|
|
|
/**
|
|
* fsi_master registration & lifetime: the fsi_master_register() and
|
|
* fsi_master_unregister() functions will take ownership of the master, and
|
|
* ->dev in particular. The registration path performs a get_device(), which
|
|
* takes the first reference on the device. Similarly, the unregistration path
|
|
* performs a put_device(), which may well drop the last reference.
|
|
*
|
|
* This means that master implementations *may* need to hold their own
|
|
* reference (via get_device()) on master->dev. In particular, if the device's
|
|
* ->release callback frees the fsi_master, then fsi_master_unregister will
|
|
* invoke this free if no other reference is held.
|
|
*
|
|
* The same applies for the error path of fsi_master_register; if the call
|
|
* fails, dev->release will have been invoked.
|
|
*/
|
|
extern int fsi_master_register(struct fsi_master *master);
|
|
extern void fsi_master_unregister(struct fsi_master *master);
|
|
|
|
extern int fsi_master_rescan(struct fsi_master *master);
|
|
|
|
#endif /* DRIVERS_FSI_MASTER_H */
|