[GitHub/mt8127/android_kernel_alcatel_ttab.git] / Documentation / i2o / ioctl


Linux I2O User Space Interface
rev 0.3 - 04/20/99

=============================================================================
Originally written by Deepak Saxena(deepak@plexity.net)
Currently maintained by Deepak Saxena(deepak@plexity.net)
=============================================================================

I. Introduction

The Linux I2O subsystem provides a set of ioctl() commands that can be
utilized by user space applications to communicate with IOPs and devices
on individual IOPs. This document defines the specific ioctl() commands
that are available to the user and provides examples of their uses.

This document assumes the reader is familiar with or has access to the
I2O specification as no I2O message parameters are outlined.  For information
on the specification, see http://www.i2osig.org

This document and the I2O user space interface are currently maintained
by Deepak Saxena.  Please send all comments, errata, and bug fixes to
deepak@csociety.purdue.edu

II. IOP Access

Access to the I2O subsystem is provided through the device file named
/dev/i2o/ctl.  This file is a character file with major number 10 and minor
number 166.  It can be created through the following command:

   mknod /dev/i2o/ctl c 10 166

III. Determining the IOP Count

   SYNOPSIS

   ioctl(fd, I2OGETIOPS,  int *count);

   u8 count[MAX_I2O_CONTROLLERS];

   DESCRIPTION

   This function returns the system's active IOP table.  count should
   point to a buffer containing MAX_I2O_CONTROLLERS entries.  Upon
   returning, each entry will contain a non-zero value if the given
   IOP unit is active, and NULL if it is inactive or non-existent.

   RETURN VALUE.

   Returns 0 if no errors occur, and -1 otherwise.  If an error occurs,
   errno is set appropriately:

     EFAULT   Invalid user space pointer was passed

IV. Getting Hardware Resource Table

   SYNOPSIS

   ioctl(fd, I2OHRTGET, struct i2o_cmd_hrt *hrt);

      struct i2o_cmd_hrtlct
      {
         u32   iop;      /* IOP unit number */
         void  *resbuf;  /* Buffer for result */
         u32   *reslen;  /* Buffer length in bytes */
      };

   DESCRIPTION

   This function returns the Hardware Resource Table of the IOP specified
   by hrt->iop in the buffer pointed to by hrt->resbuf. The actual size of
   the data is written into *(hrt->reslen).

   RETURNS

   This function returns 0 if no errors occur. If an error occurs, -1
   is returned and errno is set appropriately:

      EFAULT      Invalid user space pointer was passed
      ENXIO       Invalid IOP number
      ENOBUFS     Buffer not large enough.  If this occurs, the required
                  buffer length is written into *(hrt->reslen)

V. Getting Logical Configuration Table

   SYNOPSIS

   ioctl(fd, I2OLCTGET, struct i2o_cmd_lct *lct);

      struct i2o_cmd_hrtlct
      {
         u32   iop;      /* IOP unit number */
         void  *resbuf;  /* Buffer for result */
         u32   *reslen;  /* Buffer length in bytes */
      };

   DESCRIPTION

   This function returns the Logical Configuration Table of the IOP specified
   by lct->iop in the buffer pointed to by lct->resbuf. The actual size of
   the data is written into *(lct->reslen).

   RETURNS

   This function returns 0 if no errors occur. If an error occurs, -1
   is returned and errno is set appropriately:

      EFAULT      Invalid user space pointer was passed
      ENXIO       Invalid IOP number
      ENOBUFS     Buffer not large enough.  If this occurs, the required
                  buffer length is written into *(lct->reslen)

VI. Setting Parameters

   SYNOPSIS

   ioctl(fd, I2OPARMSET, struct i2o_parm_setget *ops);

      struct i2o_cmd_psetget
      {
         u32   iop;      /* IOP unit number */
         u32   tid;      /* Target device TID */
         void  *opbuf;   /* Operation List buffer */
         u32   oplen;    /* Operation List buffer length in bytes */
         void  *resbuf;  /* Result List buffer */
         u32   *reslen;  /* Result List buffer length in bytes */
      };

   DESCRIPTION

   This function posts a UtilParamsSet message to the device identified
   by ops->iop and ops->tid.  The operation list for the message is
   sent through the ops->opbuf buffer, and the result list is written
   into the buffer pointed to by ops->resbuf.  The number of bytes
   written is placed into *(ops->reslen).

   RETURNS

   The return value is the size in bytes of the data written into
   ops->resbuf if no errors occur.  If an error occurs, -1 is returned
   and errno is set appropriately:

      EFAULT      Invalid user space pointer was passed
      ENXIO       Invalid IOP number
      ENOBUFS     Buffer not large enough.  If this occurs, the required
                  buffer length is written into *(ops->reslen)
      ETIMEDOUT   Timeout waiting for reply message
      ENOMEM      Kernel memory allocation error

   A return value of 0 does not mean that the value was actually
   changed properly on the IOP.  The user should check the result
   list to determine the specific status of the transaction.

VII. Getting Parameters

   SYNOPSIS

   ioctl(fd, I2OPARMGET, struct i2o_parm_setget *ops);

      struct i2o_parm_setget
      {
         u32   iop;      /* IOP unit number */
         u32   tid;      /* Target device TID */
         void  *opbuf;   /* Operation List buffer */
         u32   oplen;    /* Operation List buffer length in bytes */
         void  *resbuf;  /* Result List buffer */
         u32   *reslen;  /* Result List buffer length in bytes */
      };

   DESCRIPTION

   This function posts a UtilParamsGet message to the device identified
   by ops->iop and ops->tid.  The operation list for the message is
   sent through the ops->opbuf buffer, and the result list is written
   into the buffer pointed to by ops->resbuf.  The actual size of data
   written is placed into *(ops->reslen).

   RETURNS

      EFAULT      Invalid user space pointer was passed
      ENXIO       Invalid IOP number
      ENOBUFS     Buffer not large enough.  If this occurs, the required
                  buffer length is written into *(ops->reslen)
      ETIMEDOUT   Timeout waiting for reply message
      ENOMEM      Kernel memory allocation error

   A return value of 0 does not mean that the value was actually
   properly retrieved.  The user should check the result list
   to determine the specific status of the transaction.

VIII. Downloading Software

   SYNOPSIS

   ioctl(fd, I2OSWDL, struct i2o_sw_xfer *sw);

      struct i2o_sw_xfer
      {
         u32   iop;       /* IOP unit number */
         u8    flags;     /* DownloadFlags field */
         u8    sw_type;   /* Software type */
         u32   sw_id;     /* Software ID */
         void  *buf;      /* Pointer to software buffer */
         u32   *swlen;    /* Length of software buffer */
         u32   *maxfrag;  /* Number of fragments */
         u32   *curfrag;  /* Current fragment number */
      };

   DESCRIPTION

   This function downloads a software fragment pointed by sw->buf
   to the iop identified by sw->iop. The DownloadFlags, SwID, SwType
   and SwSize fields of the ExecSwDownload message are filled in with
   the values of sw->flags, sw->sw_id, sw->sw_type and *(sw->swlen).

   The fragments _must_ be sent in order and be 8K in size. The last
   fragment _may_ be shorter, however. The kernel will compute its
   size based on information in the sw->swlen field.

   Please note that SW transfers can take a long time.

   RETURNS

   This function returns 0 no errors occur. If an error occurs, -1
   is returned and errno is set appropriately:

      EFAULT      Invalid user space pointer was passed
      ENXIO       Invalid IOP number
      ETIMEDOUT   Timeout waiting for reply message
      ENOMEM      Kernel memory allocation error

IX. Uploading Software

   SYNOPSIS

   ioctl(fd, I2OSWUL, struct i2o_sw_xfer *sw);

      struct i2o_sw_xfer
      {
         u32   iop;      /* IOP unit number */
         u8    flags; 	 /* UploadFlags */
         u8    sw_type;  /* Software type */
         u32   sw_id;    /* Software ID */
         void  *buf;     /* Pointer to software buffer */
         u32   *swlen;   /* Length of software buffer */
         u32   *maxfrag; /* Number of fragments */
         u32   *curfrag; /* Current fragment number */
      };

   DESCRIPTION

   This function uploads a software fragment from the IOP identified
   by sw->iop, sw->sw_type, sw->sw_id and optionally sw->swlen fields.
   The UploadFlags, SwID, SwType and SwSize fields of the ExecSwUpload
   message are filled in with the values of sw->flags, sw->sw_id,
   sw->sw_type and *(sw->swlen).

   The fragments _must_ be requested in order and be 8K in size. The
   user is responsible for allocating memory pointed by sw->buf. The
   last fragment _may_ be shorter.

   Please note that SW transfers can take a long time.

   RETURNS

   This function returns 0 if no errors occur.  If an error occurs, -1
   is returned and errno is set appropriately:

      EFAULT      Invalid user space pointer was passed
      ENXIO       Invalid IOP number
      ETIMEDOUT   Timeout waiting for reply message
      ENOMEM      Kernel memory allocation error

X. Removing Software

   SYNOPSIS

   ioctl(fd, I2OSWDEL, struct i2o_sw_xfer *sw);

      struct i2o_sw_xfer
      {
         u32   iop;      /* IOP unit number */
         u8    flags; 	 /* RemoveFlags */
         u8    sw_type;  /* Software type */
         u32   sw_id;    /* Software ID */
         void  *buf;     /* Unused */
         u32   *swlen;   /* Length of the software data */
         u32   *maxfrag; /* Unused */
         u32   *curfrag; /* Unused */
      };

   DESCRIPTION

   This function removes software from the IOP identified by sw->iop.
   The RemoveFlags, SwID, SwType and SwSize fields of the ExecSwRemove message
   are filled in with the values of sw->flags, sw->sw_id, sw->sw_type and
   *(sw->swlen). Give zero in *(sw->len) if the value is unknown. IOP uses
   *(sw->swlen) value to verify correct identication of the module to remove.
   The actual size of the module is written into *(sw->swlen).

   RETURNS

   This function returns 0 if no errors occur.  If an error occurs, -1
   is returned and errno is set appropriately:

      EFAULT      Invalid user space pointer was passed
      ENXIO       Invalid IOP number
      ETIMEDOUT   Timeout waiting for reply message
      ENOMEM      Kernel memory allocation error

X. Validating Configuration

   SYNOPSIS

   ioctl(fd, I2OVALIDATE, int *iop);
	u32 iop;

   DESCRIPTION

   This function posts an ExecConfigValidate message to the controller
   identified by iop. This message indicates that the current
   configuration is accepted. The iop changes the status of suspect drivers
   to valid and may delete old drivers from its store.

   RETURNS

   This function returns 0 if no erro occur.  If an error occurs, -1 is
   returned and errno is set appropriately:

      ETIMEDOUT   Timeout waiting for reply message
      ENXIO       Invalid IOP number

XI. Configuration Dialog

   SYNOPSIS

   ioctl(fd, I2OHTML, struct i2o_html *htquery);
      struct i2o_html
      {
         u32   iop;      /* IOP unit number */
         u32   tid;      /* Target device ID */
         u32   page;     /* HTML page */
         void  *resbuf;  /* Buffer for reply HTML page */
         u32   *reslen;  /* Length in bytes of reply buffer */
         void  *qbuf;    /* Pointer to HTTP query string */
         u32   qlen;     /* Length in bytes of query string buffer */
      };

   DESCRIPTION

   This function posts an UtilConfigDialog message to the device identified
   by htquery->iop and htquery->tid.  The requested HTML page number is
   provided by the htquery->page field, and the resultant data is stored
   in the buffer pointed to by htquery->resbuf.  If there is an HTTP query
   string that is to be sent to the device, it should be sent in the buffer
   pointed to by htquery->qbuf.  If there is no query string, this field
   should be set to NULL. The actual size of the reply received is written
   into *(htquery->reslen).

   RETURNS

   This function returns 0 if no error occur. If an error occurs, -1
   is returned and errno is set appropriately:

      EFAULT      Invalid user space pointer was passed
      ENXIO       Invalid IOP number
      ENOBUFS     Buffer not large enough.  If this occurs, the required
                  buffer length is written into *(ops->reslen)
      ETIMEDOUT   Timeout waiting for reply message
      ENOMEM      Kernel memory allocation error

XII. Events

    In the process of determining this.  Current idea is to have use
    the select() interface to allow user apps to periodically poll
    the /dev/i2o/ctl device for events.  When select() notifies the user
    that an event is available, the user would call read() to retrieve
    a list of all the events that are pending for the specific device.

=============================================================================
Revision History
=============================================================================

Rev 0.1 - 04/01/99
- Initial revision

Rev 0.2 - 04/06/99
- Changed return values to match UNIX ioctl() standard.  Only return values
  are 0 and -1.  All errors are reported through errno.
- Added summary of proposed possible event interfaces

Rev 0.3 - 04/20/99
- Changed all ioctls() to use pointers to user data instead of actual data
- Updated error values to match the code
Commit	Line	Data
1da177e4 LT	1
	2	Linux I2O User Space Interface
	3	rev 0.3 - 04/20/99
	4
	5	=============================================================================
	6	Originally written by Deepak Saxena(deepak@plexity.net)
	7	Currently maintained by Deepak Saxena(deepak@plexity.net)
	8	=============================================================================
	9
	10	I. Introduction
	11
	12	The Linux I2O subsystem provides a set of ioctl() commands that can be
	13	utilized by user space applications to communicate with IOPs and devices
	14	on individual IOPs. This document defines the specific ioctl() commands
	15	that are available to the user and provides examples of their uses.
	16
	17	This document assumes the reader is familiar with or has access to the
	18	I2O specification as no I2O message parameters are outlined. For information
	19	on the specification, see http://www.i2osig.org
	20
	21	This document and the I2O user space interface are currently maintained
	22	by Deepak Saxena. Please send all comments, errata, and bug fixes to
	23	deepak@csociety.purdue.edu
	24
	25	II. IOP Access
	26
	27	Access to the I2O subsystem is provided through the device file named
	28	/dev/i2o/ctl. This file is a character file with major number 10 and minor
	29	number 166. It can be created through the following command:
	30
	31	mknod /dev/i2o/ctl c 10 166
	32
	33	III. Determining the IOP Count
	34
	35	SYNOPSIS
	36
	37	ioctl(fd, I2OGETIOPS, int *count);
	38
	39	u8 count[MAX_I2O_CONTROLLERS];
	40
	41	DESCRIPTION
	42
	43	This function returns the system's active IOP table. count should
	44	point to a buffer containing MAX_I2O_CONTROLLERS entries. Upon
	45	returning, each entry will contain a non-zero value if the given
	46	IOP unit is active, and NULL if it is inactive or non-existent.
	47
	48	RETURN VALUE.
	49
	50	Returns 0 if no errors occur, and -1 otherwise. If an error occurs,
	51	errno is set appropriately:
	52
	53	EFAULT Invalid user space pointer was passed
	54
	55	IV. Getting Hardware Resource Table
	56
	57	SYNOPSIS
	58
	59	ioctl(fd, I2OHRTGET, struct i2o_cmd_hrt *hrt);
	60
	61	struct i2o_cmd_hrtlct
	62	{
	63	u32 iop; /* IOP unit number */
	64	void resbuf; / Buffer for result */
65	u32 reslen; / Buffer length in bytes */
66	};
67
68	DESCRIPTION
69
70	This function returns the Hardware Resource Table of the IOP specified
71	by hrt->iop in the buffer pointed to by hrt->resbuf. The actual size of
72	the data is written into *(hrt->reslen).
73
74	RETURNS
75
76	This function returns 0 if no errors occur. If an error occurs, -1
77	is returned and errno is set appropriately:
78
79	EFAULT Invalid user space pointer was passed
80	ENXIO Invalid IOP number
81	ENOBUFS Buffer not large enough. If this occurs, the required
82	buffer length is written into *(hrt->reslen)
83
84	V. Getting Logical Configuration Table
85
86	SYNOPSIS
87
88	ioctl(fd, I2OLCTGET, struct i2o_cmd_lct *lct);
89
90	struct i2o_cmd_hrtlct
91	{
92	u32 iop; /* IOP unit number */
93	void resbuf; / Buffer for result */
94	u32 reslen; / Buffer length in bytes */
95	};
96
97	DESCRIPTION
98
99	This function returns the Logical Configuration Table of the IOP specified
100	by lct->iop in the buffer pointed to by lct->resbuf. The actual size of
101	the data is written into *(lct->reslen).
102
103	RETURNS
104
105	This function returns 0 if no errors occur. If an error occurs, -1
106	is returned and errno is set appropriately:
107
108	EFAULT Invalid user space pointer was passed
109	ENXIO Invalid IOP number
110	ENOBUFS Buffer not large enough. If this occurs, the required
111	buffer length is written into *(lct->reslen)
112
71f66a65	113	VI. Setting Parameters
1da177e4 LT	114
	115	SYNOPSIS
	116
	117	ioctl(fd, I2OPARMSET, struct i2o_parm_setget *ops);
	118
	119	struct i2o_cmd_psetget
	120	{
	121	u32 iop; /* IOP unit number */
	122	u32 tid; /* Target device TID */
	123	void opbuf; / Operation List buffer */
	124	u32 oplen; /* Operation List buffer length in bytes */
	125	void resbuf; / Result List buffer */
	126	u32 reslen; / Result List buffer length in bytes */
	127	};
	128
	129	DESCRIPTION
	130
	131	This function posts a UtilParamsSet message to the device identified
	132	by ops->iop and ops->tid. The operation list for the message is
	133	sent through the ops->opbuf buffer, and the result list is written
	134	into the buffer pointed to by ops->resbuf. The number of bytes
	135	written is placed into *(ops->reslen).
	136
	137	RETURNS
	138
	139	The return value is the size in bytes of the data written into
	140	ops->resbuf if no errors occur. If an error occurs, -1 is returned
40e47125	141	and errno is set appropriately:
1da177e4 LT	142
	143	EFAULT Invalid user space pointer was passed
	144	ENXIO Invalid IOP number
	145	ENOBUFS Buffer not large enough. If this occurs, the required
	146	buffer length is written into *(ops->reslen)
	147	ETIMEDOUT Timeout waiting for reply message
	148	ENOMEM Kernel memory allocation error
	149
	150	A return value of 0 does not mean that the value was actually
	151	changed properly on the IOP. The user should check the result
	152	list to determine the specific status of the transaction.
	153
	154	VII. Getting Parameters
	155
	156	SYNOPSIS
	157
	158	ioctl(fd, I2OPARMGET, struct i2o_parm_setget *ops);
	159
	160	struct i2o_parm_setget
	161	{
	162	u32 iop; /* IOP unit number */
	163	u32 tid; /* Target device TID */
	164	void opbuf; / Operation List buffer */
	165	u32 oplen; /* Operation List buffer length in bytes */
	166	void resbuf; / Result List buffer */
	167	u32 reslen; / Result List buffer length in bytes */
	168	};
	169
	170	DESCRIPTION
	171
	172	This function posts a UtilParamsGet message to the device identified
	173	by ops->iop and ops->tid. The operation list for the message is
	174	sent through the ops->opbuf buffer, and the result list is written
	175	into the buffer pointed to by ops->resbuf. The actual size of data
	176	written is placed into *(ops->reslen).
	177
	178	RETURNS
	179
	180	EFAULT Invalid user space pointer was passed
	181	ENXIO Invalid IOP number
	182	ENOBUFS Buffer not large enough. If this occurs, the required
	183	buffer length is written into *(ops->reslen)
	184	ETIMEDOUT Timeout waiting for reply message
	185	ENOMEM Kernel memory allocation error
	186
	187	A return value of 0 does not mean that the value was actually
943ffb58	188	properly retrieved. The user should check the result list
1da177e4 LT	189	to determine the specific status of the transaction.
	190
	191	VIII. Downloading Software
	192
	193	SYNOPSIS
	194
	195	ioctl(fd, I2OSWDL, struct i2o_sw_xfer *sw);
	196
	197	struct i2o_sw_xfer
	198	{
	199	u32 iop; /* IOP unit number */
	200	u8 flags; /* DownloadFlags field */
	201	u8 sw_type; /* Software type */
	202	u32 sw_id; /* Software ID */
	203	void buf; / Pointer to software buffer */
	204	u32 swlen; / Length of software buffer */
	205	u32 maxfrag; / Number of fragments */
	206	u32 curfrag; / Current fragment number */
	207	};
	208
	209	DESCRIPTION
	210
	211	This function downloads a software fragment pointed by sw->buf
	212	to the iop identified by sw->iop. The DownloadFlags, SwID, SwType
	213	and SwSize fields of the ExecSwDownload message are filled in with
	214	the values of sw->flags, sw->sw_id, sw->sw_type and *(sw->swlen).
	215
	216	The fragments _must_ be sent in order and be 8K in size. The last
	217	fragment _may_ be shorter, however. The kernel will compute its
	218	size based on information in the sw->swlen field.
	219
	220	Please note that SW transfers can take a long time.
	221
	222	RETURNS
	223
	224	This function returns 0 no errors occur. If an error occurs, -1
40e47125	225	is returned and errno is set appropriately:
1da177e4 LT	226
	227	EFAULT Invalid user space pointer was passed
	228	ENXIO Invalid IOP number
	229	ETIMEDOUT Timeout waiting for reply message
	230	ENOMEM Kernel memory allocation error
	231
	232	IX. Uploading Software
	233
	234	SYNOPSIS
	235
	236	ioctl(fd, I2OSWUL, struct i2o_sw_xfer *sw);
	237
	238	struct i2o_sw_xfer
	239	{
	240	u32 iop; /* IOP unit number */
	241	u8 flags; /* UploadFlags */
	242	u8 sw_type; /* Software type */
	243	u32 sw_id; /* Software ID */
	244	void buf; / Pointer to software buffer */
	245	u32 swlen; / Length of software buffer */
	246	u32 maxfrag; / Number of fragments */
	247	u32 curfrag; / Current fragment number */
	248	};
	249
	250	DESCRIPTION
	251
	252	This function uploads a software fragment from the IOP identified
	253	by sw->iop, sw->sw_type, sw->sw_id and optionally sw->swlen fields.
	254	The UploadFlags, SwID, SwType and SwSize fields of the ExecSwUpload
	255	message are filled in with the values of sw->flags, sw->sw_id,
	256	sw->sw_type and *(sw->swlen).
	257
	258	The fragments _must_ be requested in order and be 8K in size. The
	259	user is responsible for allocating memory pointed by sw->buf. The
	260	last fragment _may_ be shorter.
	261
	262	Please note that SW transfers can take a long time.
	263
	264	RETURNS
	265
	266	This function returns 0 if no errors occur. If an error occurs, -1
40e47125	267	is returned and errno is set appropriately:
1da177e4 LT	268
	269	EFAULT Invalid user space pointer was passed
	270	ENXIO Invalid IOP number
	271	ETIMEDOUT Timeout waiting for reply message
	272	ENOMEM Kernel memory allocation error
	273
	274	X. Removing Software
	275
	276	SYNOPSIS
	277
	278	ioctl(fd, I2OSWDEL, struct i2o_sw_xfer *sw);
	279
	280	struct i2o_sw_xfer
	281	{
	282	u32 iop; /* IOP unit number */
	283	u8 flags; /* RemoveFlags */
	284	u8 sw_type; /* Software type */
	285	u32 sw_id; /* Software ID */
	286	void buf; / Unused */
	287	u32 swlen; / Length of the software data */
	288	u32 maxfrag; / Unused */
	289	u32 curfrag; / Unused */
	290	};
	291
	292	DESCRIPTION
	293
	294	This function removes software from the IOP identified by sw->iop.
	295	The RemoveFlags, SwID, SwType and SwSize fields of the ExecSwRemove message
	296	are filled in with the values of sw->flags, sw->sw_id, sw->sw_type and
	297	(sw->swlen). Give zero in (sw->len) if the value is unknown. IOP uses
	298	*(sw->swlen) value to verify correct identication of the module to remove.
	299	The actual size of the module is written into *(sw->swlen).
	300
	301	RETURNS
	302
	303	This function returns 0 if no errors occur. If an error occurs, -1
40e47125	304	is returned and errno is set appropriately:
1da177e4 LT	305
	306	EFAULT Invalid user space pointer was passed
	307	ENXIO Invalid IOP number
	308	ETIMEDOUT Timeout waiting for reply message
	309	ENOMEM Kernel memory allocation error
	310
	311	X. Validating Configuration
	312
	313	SYNOPSIS
	314
	315	ioctl(fd, I2OVALIDATE, int *iop);
	316	u32 iop;
	317
	318	DESCRIPTION
	319
	320	This function posts an ExecConfigValidate message to the controller
	321	identified by iop. This message indicates that the current
	322	configuration is accepted. The iop changes the status of suspect drivers
	323	to valid and may delete old drivers from its store.
	324
	325	RETURNS
	326
	327	This function returns 0 if no erro occur. If an error occurs, -1 is
40e47125	328	returned and errno is set appropriately:
1da177e4 LT	329
	330	ETIMEDOUT Timeout waiting for reply message
	331	ENXIO Invalid IOP number
	332
	333	XI. Configuration Dialog
	334
	335	SYNOPSIS
	336
	337	ioctl(fd, I2OHTML, struct i2o_html *htquery);
	338	struct i2o_html
	339	{
	340	u32 iop; /* IOP unit number */
	341	u32 tid; /* Target device ID */
	342	u32 page; /* HTML page */
	343	void resbuf; / Buffer for reply HTML page */
	344	u32 reslen; / Length in bytes of reply buffer */
	345	void qbuf; / Pointer to HTTP query string */
	346	u32 qlen; /* Length in bytes of query string buffer */
	347	};
	348
	349	DESCRIPTION
	350
	351	This function posts an UtilConfigDialog message to the device identified
	352	by htquery->iop and htquery->tid. The requested HTML page number is
	353	provided by the htquery->page field, and the resultant data is stored
	354	in the buffer pointed to by htquery->resbuf. If there is an HTTP query
	355	string that is to be sent to the device, it should be sent in the buffer
	356	pointed to by htquery->qbuf. If there is no query string, this field
	357	should be set to NULL. The actual size of the reply received is written
	358	into *(htquery->reslen).
	359
	360	RETURNS
	361
	362	This function returns 0 if no error occur. If an error occurs, -1
40e47125	363	is returned and errno is set appropriately:
1da177e4 LT	364
	365	EFAULT Invalid user space pointer was passed
	366	ENXIO Invalid IOP number
	367	ENOBUFS Buffer not large enough. If this occurs, the required
	368	buffer length is written into *(ops->reslen)
	369	ETIMEDOUT Timeout waiting for reply message
	370	ENOMEM Kernel memory allocation error
	371
	372	XII. Events
	373
	374	In the process of determining this. Current idea is to have use
	375	the select() interface to allow user apps to periodically poll
	376	the /dev/i2o/ctl device for events. When select() notifies the user
	377	that an event is available, the user would call read() to retrieve
	378	a list of all the events that are pending for the specific device.
	379
	380	=============================================================================
	381	Revision History
	382	=============================================================================
	383
	384	Rev 0.1 - 04/01/99
	385	- Initial revision
	386
	387	Rev 0.2 - 04/06/99
	388	- Changed return values to match UNIX ioctl() standard. Only return values
	389	are 0 and -1. All errors are reported through errno.
	390	- Added summary of proposed possible event interfaces
	391
	392	Rev 0.3 - 04/20/99
	393	- Changed all ioctls() to use pointers to user data instead of actual data
	394	- Updated error values to match the code