[U-Boot] [PATCH 01/11] drivers: core: device: add support to check dt compatible for a device/machine

[Mugunthan V N]

Provide an api to check whether the given device or machine is
compatible with the given compat string which helps in making
decisions in drivers based on device or machine compatible.

Idea taken from Linux.

Signed-off-by: Mugunthan V N <mugunthanvnm at ti.com>
---
 drivers/core/device.c | 27 +++++++++++++++++++++++++++
 include/dm/device.h   | 23 +++++++++++++++++++++++
 2 files changed, 50 insertions(+)

diff --git a/drivers/core/device.c b/drivers/core/device.c
index cb24a61..445b22e 100644
--- a/drivers/core/device.c
+++ b/drivers/core/device.c
@@ -691,3 +691,30 @@ int device_set_name(struct udevice *dev, const char *name)
 
 	return 0;
 }
+
+bool of_device_is_compatible(int offset, const char *compat)
+{
+	const void *fdt = gd->fdt_blob;
+	const char *str;
+	int str_len;
+	int len = 0;
+
+	str = fdt_getprop(fdt, 0, "compatible", &str_len);
+	if(!str) {
+		debug("compatible field not found in node(%d)\n", offset);
+		return false;
+	}
+
+	while (len < str_len) {
+		if (!strcmp(compat, &str[len]))
+			return true;
+		len += strlen(&str[len]) + 1;
+	}
+
+	return false;
+}
+
+bool of_machine_is_compatible(const char *compat)
+{
+	return of_device_is_compatible(0, compat);
+}
diff --git a/include/dm/device.h b/include/dm/device.h
index 1cf8150..9a1b3d0 100644
--- a/include/dm/device.h
+++ b/include/dm/device.h
@@ -510,6 +510,29 @@ bool device_is_last_sibling(struct udevice *dev);
 int device_set_name(struct udevice *dev, const char *name);
 
 /**
+ * of_device_is_compatible() - check if the device is compatible with the compat
+ *
+ * This allows to check whether the device is comaptible with the compat.
+ *
+ * @offset:	Offset to the device
+ * @compat:	Compatible string which needs to verified in the given
+ *		device offset
+ * @return true if OK, false if the compatible is not found
+ */
+bool of_device_is_compatible(int offset, const char *compat);
+
+/**
+ * of_machine_is_compatible() - check if the machine is compatible with
+ *				the compat
+ *
+ * This allows to check whether the machine is comaptible with the compat.
+ *
+ * @compat:	Compatible string which needs to verified
+ * @return true if OK, false if the compatible is not found
+ */
+bool of_machine_is_compatible(const char *compat);
+
+/**
  * device_is_on_pci_bus - Test if a device is on a PCI bus
  *
  * @dev:	device to test
-- 
2.8.1.101.g72d917a