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linux/include/asm-s390/chpid.h
Cornelia Huck 9d92a7e1b0 [S390] cio: Add chsc subchannel driver.
This patch adds a driver for subchannels of type chsc.

A device /dev/chsc is created which may be used to issue ioctls to:
- obtain information about the machine's I/O configuration
- dynamically change the machine's I/O configuration via
  asynchronous chsc commands

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-07-14 10:02:12 +02:00

57 lines
1.0 KiB
C

/*
* drivers/s390/cio/chpid.h
*
* Copyright IBM Corp. 2007
* Author(s): Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
*/
#ifndef _ASM_S390_CHPID_H
#define _ASM_S390_CHPID_H _ASM_S390_CHPID_H
#include <linux/string.h>
#include <asm/types.h>
#define __MAX_CHPID 255
struct chp_id {
u8 reserved1;
u8 cssid;
u8 reserved2;
u8 id;
} __attribute__((packed));
static inline void chp_id_init(struct chp_id *chpid)
{
memset(chpid, 0, sizeof(struct chp_id));
}
static inline int chp_id_is_equal(struct chp_id *a, struct chp_id *b)
{
return (a->id == b->id) && (a->cssid == b->cssid);
}
static inline void chp_id_next(struct chp_id *chpid)
{
if (chpid->id < __MAX_CHPID)
chpid->id++;
else {
chpid->id = 0;
chpid->cssid++;
}
}
#ifdef __KERNEL__
#include <asm/cio.h>
static inline int chp_id_is_valid(struct chp_id *chpid)
{
return (chpid->cssid <= __MAX_CSSID);
}
#define chp_id_for_each(c) \
for (chp_id_init(c); chp_id_is_valid(c); chp_id_next(c))
#endif /* __KERNEL */
#endif /* _ASM_S390_CHPID_H */