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);


SEE ALSO


ddi_prop_get_int(9F), ddi_prop_get_int64(9F), ldi_prop_exists(9F)


Writing Device Drivers

June 3, 2003 LDI_PROP_GET_INT(9F)

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