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.