[S390] cio: Add docbook comments.
Comment a bunch of function in docbook style and convert existing
comments on structures to docbook.
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>
diff --git a/include/asm-s390/cio.h b/include/asm-s390/cio.h
index 1982fb3..2f08c16 100644
--- a/include/asm-s390/cio.h
+++ b/include/asm-s390/cio.h
@@ -15,30 +15,50 @@
#define LPM_ANYPATH 0xff
#define __MAX_CSSID 0
-/*
- * subchannel status word
+/**
+ * struct scsw - subchannel status word
+ * @key: subchannel key
+ * @sctl: suspend control
+ * @eswf: esw format
+ * @cc: deferred condition code
+ * @fmt: format
+ * @pfch: prefetch
+ * @isic: initial-status interruption control
+ * @alcc: adress-limit checking control
+ * @ssi: supress-suspended interruption
+ * @zcc: zero condition code
+ * @ectl: extended control
+ * @pno: path not operational
+ * @res: reserved
+ * @fctl: function control
+ * @actl: activity control
+ * @stctl: status control
+ * @cpa: channel program address
+ * @dstat: device status
+ * @cstat: subchannel status
+ * @count: residual count
*/
struct scsw {
- __u32 key : 4; /* subchannel key */
- __u32 sctl : 1; /* suspend control */
- __u32 eswf : 1; /* ESW format */
- __u32 cc : 2; /* deferred condition code */
- __u32 fmt : 1; /* format */
- __u32 pfch : 1; /* prefetch */
- __u32 isic : 1; /* initial-status interruption control */
- __u32 alcc : 1; /* address-limit checking control */
- __u32 ssi : 1; /* supress-suspended interruption */
- __u32 zcc : 1; /* zero condition code */
- __u32 ectl : 1; /* extended control */
- __u32 pno : 1; /* path not operational */
- __u32 res : 1; /* reserved */
- __u32 fctl : 3; /* function control */
- __u32 actl : 7; /* activity control */
- __u32 stctl : 5; /* status control */
- __u32 cpa; /* channel program address */
- __u32 dstat : 8; /* device status */
- __u32 cstat : 8; /* subchannel status */
- __u32 count : 16; /* residual count */
+ __u32 key : 4;
+ __u32 sctl : 1;
+ __u32 eswf : 1;
+ __u32 cc : 2;
+ __u32 fmt : 1;
+ __u32 pfch : 1;
+ __u32 isic : 1;
+ __u32 alcc : 1;
+ __u32 ssi : 1;
+ __u32 zcc : 1;
+ __u32 ectl : 1;
+ __u32 pno : 1;
+ __u32 res : 1;
+ __u32 fctl : 3;
+ __u32 actl : 7;
+ __u32 stctl : 5;
+ __u32 cpa;
+ __u32 dstat : 8;
+ __u32 cstat : 8;
+ __u32 count : 16;
} __attribute__ ((packed));
#define SCSW_FCTL_CLEAR_FUNC 0x1
@@ -110,11 +130,22 @@
#define SNS2_ENV_DATA_PRESENT 0x10
#define SNS2_INPRECISE_END 0x04
+/**
+ * struct ccw1 - channel command word
+ * @cmd_code: command code
+ * @flags: flags, like IDA adressing, etc.
+ * @count: byte count
+ * @cda: data address
+ *
+ * The ccw is the basic structure to build channel programs that perform
+ * operations with the device or the control unit. Only Format-1 channel
+ * command words are supported.
+ */
struct ccw1 {
- __u8 cmd_code; /* command code */
- __u8 flags; /* flags, like IDA addressing, etc. */
- __u16 count; /* byte count */
- __u32 cda; /* data address */
+ __u8 cmd_code;
+ __u8 flags;
+ __u16 count;
+ __u32 cda;
} __attribute__ ((packed,aligned(8)));
#define CCW_FLAG_DC 0x80
@@ -140,102 +171,162 @@
#define SENSE_MAX_COUNT 0x20
+/**
+ * struct erw - extended report word
+ * @res0: reserved
+ * @auth: authorization check
+ * @pvrf: path-verification-required flag
+ * @cpt: channel-path timeout
+ * @fsavf: failing storage address validity flag
+ * @cons: concurrent sense
+ * @scavf: secondary ccw address validity flag
+ * @fsaf: failing storage address format
+ * @scnt: sense count, if @cons == %1
+ * @res16: reserved
+ */
struct erw {
- __u32 res0 : 3; /* reserved */
- __u32 auth : 1; /* Authorization check */
- __u32 pvrf : 1; /* path-verification-required flag */
- __u32 cpt : 1; /* channel-path timeout */
- __u32 fsavf : 1; /* Failing storage address validity flag */
- __u32 cons : 1; /* concurrent-sense */
- __u32 scavf : 1; /* Secondary ccw address validity flag */
- __u32 fsaf : 1; /* Failing storage address format */
- __u32 scnt : 6; /* sense count if cons == 1 */
- __u32 res16 : 16; /* reserved */
+ __u32 res0 : 3;
+ __u32 auth : 1;
+ __u32 pvrf : 1;
+ __u32 cpt : 1;
+ __u32 fsavf : 1;
+ __u32 cons : 1;
+ __u32 scavf : 1;
+ __u32 fsaf : 1;
+ __u32 scnt : 6;
+ __u32 res16 : 16;
} __attribute__ ((packed));
-/*
- * subchannel logout area
+/**
+ * struct sublog - subchannel logout area
+ * @res0: reserved
+ * @esf: extended status flags
+ * @lpum: last path used mask
+ * @arep: ancillary report
+ * @fvf: field-validity flags
+ * @sacc: storage access code
+ * @termc: termination code
+ * @devsc: device-status check
+ * @serr: secondary error
+ * @ioerr: i/o-error alert
+ * @seqc: sequence code
*/
struct sublog {
- __u32 res0 : 1; /* reserved */
- __u32 esf : 7; /* extended status flags */
- __u32 lpum : 8; /* last path used mask */
- __u32 arep : 1; /* ancillary report */
- __u32 fvf : 5; /* field-validity flags */
- __u32 sacc : 2; /* storage access code */
- __u32 termc : 2; /* termination code */
- __u32 devsc : 1; /* device-status check */
- __u32 serr : 1; /* secondary error */
- __u32 ioerr : 1; /* i/o-error alert */
- __u32 seqc : 3; /* sequence code */
+ __u32 res0 : 1;
+ __u32 esf : 7;
+ __u32 lpum : 8;
+ __u32 arep : 1;
+ __u32 fvf : 5;
+ __u32 sacc : 2;
+ __u32 termc : 2;
+ __u32 devsc : 1;
+ __u32 serr : 1;
+ __u32 ioerr : 1;
+ __u32 seqc : 3;
} __attribute__ ((packed));
-/*
- * Format 0 Extended Status Word (ESW)
+/**
+ * struct esw0 - Format 0 Extended Status Word (ESW)
+ * @sublog: subchannel logout
+ * @erw: extended report word
+ * @faddr: failing storage address
+ * @saddr: secondary ccw address
*/
struct esw0 {
- struct sublog sublog; /* subchannel logout */
- struct erw erw; /* extended report word */
- __u32 faddr[2]; /* failing storage address */
- __u32 saddr; /* secondary ccw address */
+ struct sublog sublog;
+ struct erw erw;
+ __u32 faddr[2];
+ __u32 saddr;
} __attribute__ ((packed));
-/*
- * Format 1 Extended Status Word (ESW)
+/**
+ * struct esw1 - Format 1 Extended Status Word (ESW)
+ * @zero0: reserved zeros
+ * @lpum: last path used mask
+ * @zero16: reserved zeros
+ * @erw: extended report word
+ * @zeros: three fullwords of zeros
*/
struct esw1 {
- __u8 zero0; /* reserved zeros */
- __u8 lpum; /* last path used mask */
- __u16 zero16; /* reserved zeros */
- struct erw erw; /* extended report word */
- __u32 zeros[3]; /* 2 fullwords of zeros */
+ __u8 zero0;
+ __u8 lpum;
+ __u16 zero16;
+ struct erw erw;
+ __u32 zeros[3];
} __attribute__ ((packed));
-/*
- * Format 2 Extended Status Word (ESW)
+/**
+ * struct esw2 - Format 2 Extended Status Word (ESW)
+ * @zero0: reserved zeros
+ * @lpum: last path used mask
+ * @dcti: device-connect-time interval
+ * @erw: extended report word
+ * @zeros: three fullwords of zeros
*/
struct esw2 {
- __u8 zero0; /* reserved zeros */
- __u8 lpum; /* last path used mask */
- __u16 dcti; /* device-connect-time interval */
- struct erw erw; /* extended report word */
- __u32 zeros[3]; /* 2 fullwords of zeros */
+ __u8 zero0;
+ __u8 lpum;
+ __u16 dcti;
+ struct erw erw;
+ __u32 zeros[3];
} __attribute__ ((packed));
-/*
- * Format 3 Extended Status Word (ESW)
+/**
+ * struct esw3 - Format 3 Extended Status Word (ESW)
+ * @zero0: reserved zeros
+ * @lpum: last path used mask
+ * @res: reserved
+ * @erw: extended report word
+ * @zeros: three fullwords of zeros
*/
struct esw3 {
- __u8 zero0; /* reserved zeros */
- __u8 lpum; /* last path used mask */
- __u16 res; /* reserved */
- struct erw erw; /* extended report word */
- __u32 zeros[3]; /* 2 fullwords of zeros */
+ __u8 zero0;
+ __u8 lpum;
+ __u16 res;
+ struct erw erw;
+ __u32 zeros[3];
} __attribute__ ((packed));
-/*
- * interruption response block
+/**
+ * struct irb - interruption response block
+ * @scsw: subchannel status word
+ * @esw: extened status word, 4 formats
+ * @ecw: extended control word
+ *
+ * The irb that is handed to the device driver when an interrupt occurs. For
+ * solicited interrupts, the common I/O layer already performs checks whether
+ * a field is valid; a field not being valid is always passed as %0.
+ * If a unit check occured, @ecw may contain sense data; this is retrieved
+ * by the common I/O layer itself if the device doesn't support concurrent
+ * sense (so that the device driver never needs to perform basic sene itself).
+ * For unsolicited interrupts, the irb is passed as-is (expect for sense data,
+ * if applicable).
*/
struct irb {
- struct scsw scsw; /* subchannel status word */
- union { /* extended status word, 4 formats */
+ struct scsw scsw;
+ union {
struct esw0 esw0;
struct esw1 esw1;
struct esw2 esw2;
struct esw3 esw3;
} esw;
- __u8 ecw[32]; /* extended control word */
+ __u8 ecw[32];
} __attribute__ ((packed,aligned(4)));
-/*
- * command information word (CIW) layout
+/**
+ * struct ciw - command information word (CIW) layout
+ * @et: entry type
+ * @reserved: reserved bits
+ * @ct: command type
+ * @cmd: command code
+ * @count: command count
*/
struct ciw {
- __u32 et : 2; /* entry type */
- __u32 reserved : 2; /* reserved */
- __u32 ct : 4; /* command type */
- __u32 cmd : 8; /* command */
- __u32 count : 16; /* coun */
+ __u32 et : 2;
+ __u32 reserved : 2;
+ __u32 ct : 4;
+ __u32 cmd : 8;
+ __u32 count : 16;
} __attribute__ ((packed));
#define CIW_TYPE_RCD 0x0 /* read configuration data */
@@ -258,11 +349,32 @@
/* Sick revalidation of device. */
#define CIO_REVALIDATE 0x0008
+/**
+ * struct ccw_dev_id - unique identifier for ccw devices
+ * @ssid: subchannel set id
+ * @devno: device number
+ *
+ * This structure is not directly based on any hardware structure. The
+ * hardware identifies a device by its device number and its subchannel,
+ * which is in turn identified by its id. In order to get a unique identifier
+ * for ccw devices across subchannel sets, @struct ccw_dev_id has been
+ * introduced.
+ */
struct ccw_dev_id {
u8 ssid;
u16 devno;
};
+/**
+ * ccw_device_id_is_equal() - compare two ccw_dev_ids
+ * @dev_id1: a ccw_dev_id
+ * @dev_id2: another ccw_dev_id
+ * Returns:
+ * %1 if the two structures are equal field-by-field,
+ * %0 if not.
+ * Context:
+ * any
+ */
static inline int ccw_dev_id_is_equal(struct ccw_dev_id *dev_id1,
struct ccw_dev_id *dev_id2)
{