ofw_bus_is_compatible
ofw_bus_is_compatible_strict
ofw_bus_node_is_compatible
ofw_bus_search_compatible
—
check device tree nodes for compatibility with
drivers
#include
<dev/ofw/openfirm.h>
#include
<dev/ofw/ofw_bus.h>
#include
<dev/ofw/ofw_bus_subr.h>
int
ofw_bus_is_compatible
(
device_t
dev,
const char
*compatstr);
int
ofw_bus_is_compatible_strict
(
device_t
dev,
const char
*compatstr);
int
ofw_bus_node_is_compatible
(
phandle_t
node,
const char
*compatstr);
const struct ofw_compat_data *
ofw_bus_search_compatible
(
device_t
dev,
const
struct ofw_compat_data *compat);
The "compatible" property of the device tree node is used to identify
the type of the device the node represents. The property is a list of one or
more strings that represent hardware types the device is compatible with. The
common format for such strings is "vendor,hardware" where
"vendor" is an abbreviated name of the manufacturer and
"hardware" is a device identifier, for instance, "fsl" for
"Freescale" and "imx6ul-i2c" for the I2C controller. More
than one string is required for compatibility with older revisions of the
driver. If hardware revision B is backward compatible with revision A device
tree node can signal this compatibility by providing both
"vndr,hrdwrA" and "vndr,hrdwrB" strings in the
"compatibile" property value. This way older driver can use features
available only in revision A, and the new version of the driver can take
advantage of revision B feature set.
ofw_bus_is_compatible
() returns 1 if the
compatstr value occurs in the
"compatible" property list of the device tree node associated with
the device
dev, and 0 otherwise.
ofw_bus_is_compatible_strict
() return 1 if
the "compatible" property of the device tree node associated with
the device
dev consists of only one string
and this string is equal to
compatstr, and 0
otherwise.
ofw_bus_node_is_compatible
() returns 1 if the
compatstr value occurs in the
"compatible" property list of the device tree node
node, and 0 otherwise.
ofw_bus_search_compatible
() returns pointer
to the first entry of the
compat table whose
ocd_str field occurs in "compatible" property of the device tree
node associated with the device
dev. The
compat table is an array of struct
ofw_compat_data elements defined as follows:
struct ofw_compat_data {
const char *ocd_str;
uintptr_t ocd_data;
};
The
compat table must be terminated by the
entry with ocd_str set to NULL. If the device tree node is not compatible with
any of the entries, the function returns the pointer to the terminating entry.
static struct ofw_compat_data compat_data[] = {
{"arm,hrdwrA", FEATURE_A},
{"arm,hrdwrB", FEATURE_A | FEATURE_B},
{NULL, 0}
};
static int
hrdwr_probe(device_t dev)
{
...
if (!ofw_bus_search_compatible(dev, compat_data)->ocd_data)
return (ENXIO);
...
}
static int
hrdwr_attach(device_t dev)
{
...
sc = device_get_softc(dev);
sc->sc_features = ofw_bus_search_compatible(dev, compat_data)->ocd_data;
...
}
ofw_bus_find_compatible(9)
This manual page was written by
Oleksandr
Tymoshenko.