[U-Boot] [PATCH] misc: fs_loader: Replace label with DT phandle

[tien.fong.chee at intel.com]

From: Tien Fong Chee <tien.fong.chee at intel.com>

In previously label which will be expanded to the node's full path was
used, and now replacing label with most commonly used DT phandle. The
codes were changed accordingly to the use of DT phandle and supporting
multiple instances.

Signed-off-by: Tien Fong Chee <tien.fong.chee at intel.com>
---
 doc/driver-model/fs_firmware_loader.txt |   58 +++++++++++++++++++++++++------
 drivers/misc/fs_loader.c                |   36 ++++++++-----------
 2 files changed, 62 insertions(+), 32 deletions(-)

diff --git a/doc/driver-model/fs_firmware_loader.txt b/doc/driver-model/fs_firmware_loader.txt
index b9aee84..d9f966e 100644
--- a/doc/driver-model/fs_firmware_loader.txt
+++ b/doc/driver-model/fs_firmware_loader.txt
@@ -1,4 +1,4 @@
-# Copyright (C) 2018 Intel Corporation <www.intel.com>
+# Copyright (C) 2018-2019 Intel Corporation <www.intel.com>
 #
 # SPDX-License-Identifier:    GPL-2.0
 
@@ -46,15 +46,48 @@ Firmware storage device described in device tree source
 		ubivol = "ubi0";
 	};
 
-	Then, firmware_loader property would be set with the path of fs_loader
-	node under /chosen node such as:
+	Then, firmware-loader property can be added with any device node, which
+	driver would use the firmware loader for loading.
+
+	The value of the firmware-loader property should be set with phandle
+	of the fs-loader node.
+	For example:
+		firmware-loader = <&fs_loader0>;
+
+	If there are majority of devices using the same fs-loader node, then
+	firmware-loader property can be added under /chosen node instead of
+	adding to each of device node.
+
+	For example:
 	/{
 		chosen {
-			firmware_loader = &fs_loader0;
+			firmware-loader = <&fs_loader0>;
 		};
 	};
 
-	However, this driver is also designed to support U-boot environment
+	In each respective driver of devices using firmware loader, the firmware
+	loaded instance	should be created by DT phandle.
+
+	For example of getting DT phandle from /chosen and creating instance:
+	chosen_node = ofnode_path("/chosen");
+	if (!ofnode_valid(chosen_node)) {
+		debug("/chosen node was not found.\n");
+		return -ENOENT;
+	}
+
+	phandle_p = ofnode_get_property(chosen_node, "firmware-loader", &size);
+	if (!phandle_p) {
+		debug("firmware-loader property was not found.\n");
+		return -ENOENT;
+	}
+
+	phandle = fdt32_to_cpu(*phandle_p);
+	ret = uclass_get_device_by_phandle_id(UCLASS_FS_FIRMWARE_LOADER,
+					     phandle, &dev);
+	if (ret)
+		return ret;
+
+	Firmware loader driver is also designed to support U-boot environment
 	variables, so all these data from FDT can be overwritten
 	through the U-boot environment variable during run time.
 	For examples:
@@ -104,9 +137,12 @@ return:
 Description:
 	The firmware is loaded directly into the buffer pointed to by buf
 
-Example of creating firmware loader instance and calling
-request_firmware_into_buf API:
-	if (uclass_get_device(UCLASS_FS_FIRMWARE_LOADER, 0, &dev)) {
-		request_firmware_into_buf(dev, filename, buffer_location,
-					 buffer_size, offset_ofreading);
-	}
+Example of calling request_firmware_into_buf API after creating firmware loader
+instance:
+	ret = uclass_get_device_by_phandle_id(UCLASS_FS_FIRMWARE_LOADER,
+					     phandle, &dev);
+	if (ret)
+		return ret;
+
+	request_firmware_into_buf(dev, filename, buffer_location, buffer_size,
+				 offset_ofreading);
diff --git a/drivers/misc/fs_loader.c b/drivers/misc/fs_loader.c
index a2e3763..f42eeff 100644
--- a/drivers/misc/fs_loader.c
+++ b/drivers/misc/fs_loader.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
  /*
- * Copyright (C) 2018 Intel Corporation <www.intel.com>
+ * Copyright (C) 2018-2019 Intel Corporation <www.intel.com>
  *
  */
 #include <common.h>
@@ -219,32 +219,26 @@ int request_firmware_into_buf(struct udevice *dev,
 
 static int fs_loader_ofdata_to_platdata(struct udevice *dev)
 {
-	const char *fs_loader_path;
 	u32 phandlepart[2];
 
-	fs_loader_path = ofnode_get_chosen_prop("firmware-loader");
+	ofnode fs_loader_node = dev_ofnode(dev);
 
-	if (fs_loader_path) {
-		ofnode fs_loader_node;
+	if (ofnode_valid(fs_loader_node)) {
+		struct device_platdata *plat;
 
-		fs_loader_node = ofnode_path(fs_loader_path);
-		if (ofnode_valid(fs_loader_node)) {
-			struct device_platdata *plat;
-			plat = dev->platdata;
-
-			if (!ofnode_read_u32_array(fs_loader_node,
-						  "phandlepart",
-						  phandlepart, 2)) {
-				plat->phandlepart.phandle = phandlepart[0];
-				plat->phandlepart.partition = phandlepart[1];
-			}
+		plat = dev->platdata;
+		if (!ofnode_read_u32_array(fs_loader_node,
+					  "phandlepart",
+					  phandlepart, 2)) {
+			plat->phandlepart.phandle = phandlepart[0];
+			plat->phandlepart.partition = phandlepart[1];
+		}
 
-			plat->mtdpart = (char *)ofnode_read_string(
-					 fs_loader_node, "mtdpart");
+		plat->mtdpart = (char *)ofnode_read_string(
+				 fs_loader_node, "mtdpart");
 
-			plat->ubivol = (char *)ofnode_read_string(
-					 fs_loader_node, "ubivol");
-		}
+		plat->ubivol = (char *)ofnode_read_string(
+				 fs_loader_node, "ubivol");
 	}
 
 	return 0;
-- 
1.7.7.4