illumos: manual page: ldi_prop_get

LDI_PROP_GET_INT(9F) Kernel Functions for Drivers LDI_PROP_GET_INT(9F)

NAME

ldi_prop_get_int, ldi_prop_get_int64 - Lookup integer property

SYNOPSIS

#include <sys/sunldi.h>

int ldi_prop_get_int(ldi_handle_t lh, uint_t flags, char *name,
int defvalue);

int64_t ldi_prop_get_int64(ldi_handle_t lh, uint_t flags, char *name,
int64_t defvalue);

PARAMETERS

lh
Layered handle.

flags
Possible flag values are some combination of:

LDI_DEV_T_ANY
Match the lookup request independent of
the actual dev_t value that was used when
the property was created. Indicates any
dev_t value (including DDI_DEV_T_NONE)
associated with a possible property match
satisfies the matching criteria.

DDI_PROP_DONTPASS
Do not pass request to parent device
information node if property not found.

DDI_PROP_NOTPROM
Do not look at PROM properties (ignored on
platforms that do not support PROM
properties).

name
String containing the property name.

defvalue
Integer value that is returned if the property is not found.

INTERFACE LEVEL

illumos DDI specific (illumos DDI)

DESCRIPTION

The ldi_prop_get_int() and ldi_prop_get_int64() functions search for an
integer property associated with a device represented by the layered
driver handle. If the integer property is found, the functions return the
property value.

Properties are searched for based on the dip and dev_t values associated
with the layered handle, the property name, and type of the data
(integer).

The property search order is as follows:

1. Search software properties created by the driver.

2. Search the software properties created by the system (or nexus
nodes in the device info tree).

3. Search the driver global properties list.

4. If DDI_PROP_NOTPROM is not set, search the PROM properties (if
they exist).

5. If DDI_PROP_DONTPASS is not set, pass this request to the
parent device information node of the device represented by
the layered handle.

6. Return defvalue.

Typically, the specific dev_t value associated with the device
represented by the layered handle (ldi_handle_t) is used as a part of the
property match criteria. This association is handled by the layered
driver infrastructure on behalf of the consumers of the ldi property look
up functions.

However, if the LDI_DEV_T_ANY flag is used, the ldi property lookup
functions match the request regardless of the dev_t value associated with
the property at the time of its creation. If a property was created with
a dev_t set to DDI_DEV_T_NONE, the only way to look up this property is
with the LDI_DEV_T_ANY flag. PROM properties are always created with a
dev_t set to DDI_DEV_T_NONE.

name must always be set to the name of the property being looked up.

The return value of the routine is the value of property. If the property
is not found, the argument defvalue is returned as the property value.

ldi_prop_get_int64() does not search the PROM for 64-bit property values.

RETURN VALUES

ldi_prop_get_int() and ldi_prop_get_int64() return the property value. If
the property is not found, the argument defvalue is returned. If the
property is found, but cannot be decoded into an int or an int64_t,
DDI_PROP_NOT_FOUND is returned.

CONTEXT

ldi_prop_get_int() and ldi_prop_get_int64() can be called from user or
kernel context.

EXAMPLES

Using ldi_prop_get_int64().

The following example demonstrates the use of ldi_prop_get_int64().

/*
* Get the value of the integer "timeout" property, using
* our own default if no such property exists
*/

int64_t timeout, defval;

timeout = ldi_prop_get_int64(lh, LDI_DEV_T_ANY|DDI_PROP_DONTPASS,
propname, defval);