ddi_prop_exists(9F) Kernel Functions for Drivers ddi_prop_exists(9F)NAMEddi_prop_exists - check for the existence of a property
SYNOPSIS
#include <sys/ddi.h>
#include <sys/sunddi.h>
int ddi_prop_exists(dev_t match_dev, dev_info_t *dip, uint_t flags,
char *name);
INTERFACE LEVEL
Solaris DDI specific (Solaris DDI).
PARAMETERS
match_dev Device number associated with property or
DDI_DEV_T_ANY.
dip Pointer to the device info node of device whose prop‐
erty list should be searched.
flags Possible flag values are some combination of:
"small and bold">DDI_PROP_DONTPASS
Do not pass request to parent device information
node if the property is not found.
DDI_PROP_NOTPROM
Do not look at PROM properties (ignored on plat‐
forms that do not support
PROM properties).
name String containing the name of the property.
DESCRIPTIONddi_prop_exists() checks for the existence of a property regardless of
the property value data type.
Properties are searched for based on the dip, name, and match_dev. 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.
6. Return 0 if not found and 1 if found.
Usually, the match_dev argument should be set to the actual device num‐
ber that this property is associated with. However, if the match_dev
argument is DDI_DEV_T_ANY, then ddi_prop_exists() will match the
request regardless of the match_dev the property was created with.
That is the first property whose name matches name will be returned.
If a property was created with match_dev set to DDI_DEV_T_NONE then
the only way to look up this property is with a match_dev set to
DDI_DEV_T_ANY. PROM properties are always created with match_dev set to
DDI_DEV_T_NONE.
name must always be set to the name of the property being looked up.
RETURN VALUESddi_prop_exists() returns 1 if the property exists and 0 otherwise.
CONTEXT
These functions can be called from user or kernel context.
EXAMPLES
Example 1: : Using ddi_prop_exists()
The following example demonstrates the use of ddi_prop_exists().
/*
* Enable "whizzy" mode if the "whizzy-mode" property exists
*/
if (ddi_prop_exists(xx_dev, xx_dip, DDI_PROP_NOTPROM,
"whizzy-mode") == 1) {
xx_enable_whizzy_mode(xx_dip);
} else {
xx_disable_whizzy_mode(xx_dip);
}
SEE ALSOddi_prop_get_int(9F), ddi_prop_lookup(9F), ddi_prop_remove(9F),
ddi_prop_update(9F)
Writing Device Drivers
SunOS 5.10 22 May 1995 ddi_prop_exists(9F)
