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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /scripts/dtc/fdtput.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'scripts/dtc/fdtput.c')
-rw-r--r--scripts/dtc/fdtput.c348
1 files changed, 348 insertions, 0 deletions
diff --git a/scripts/dtc/fdtput.c b/scripts/dtc/fdtput.c
new file mode 100644
index 000000000..a363c3cab
--- /dev/null
+++ b/scripts/dtc/fdtput.c
@@ -0,0 +1,348 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
+ */
+
+#include <assert.h>
+#include <ctype.h>
+#include <getopt.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <libfdt.h>
+
+#include "util.h"
+
+/* These are the operations we support */
+enum oper_type {
+ OPER_WRITE_PROP, /* Write a property in a node */
+ OPER_CREATE_NODE, /* Create a new node */
+};
+
+struct display_info {
+ enum oper_type oper; /* operation to perform */
+ int type; /* data type (s/i/u/x or 0 for default) */
+ int size; /* data size (1/2/4) */
+ int verbose; /* verbose output */
+ int auto_path; /* automatically create all path components */
+};
+
+
+/**
+ * Report an error with a particular node.
+ *
+ * @param name Node name to report error on
+ * @param namelen Length of node name, or -1 to use entire string
+ * @param err Error number to report (-FDT_ERR_...)
+ */
+static void report_error(const char *name, int namelen, int err)
+{
+ if (namelen == -1)
+ namelen = strlen(name);
+ fprintf(stderr, "Error at '%1.*s': %s\n", namelen, name,
+ fdt_strerror(err));
+}
+
+/**
+ * Encode a series of arguments in a property value.
+ *
+ * @param disp Display information / options
+ * @param arg List of arguments from command line
+ * @param arg_count Number of arguments (may be 0)
+ * @param valuep Returns buffer containing value
+ * @param *value_len Returns length of value encoded
+ */
+static int encode_value(struct display_info *disp, char **arg, int arg_count,
+ char **valuep, int *value_len)
+{
+ char *value = NULL; /* holding area for value */
+ int value_size = 0; /* size of holding area */
+ char *ptr; /* pointer to current value position */
+ int len; /* length of this cell/string/byte */
+ int ival;
+ int upto; /* the number of bytes we have written to buf */
+ char fmt[3];
+
+ upto = 0;
+
+ if (disp->verbose)
+ fprintf(stderr, "Decoding value:\n");
+
+ fmt[0] = '%';
+ fmt[1] = disp->type ? disp->type : 'd';
+ fmt[2] = '\0';
+ for (; arg_count > 0; arg++, arg_count--, upto += len) {
+ /* assume integer unless told otherwise */
+ if (disp->type == 's')
+ len = strlen(*arg) + 1;
+ else
+ len = disp->size == -1 ? 4 : disp->size;
+
+ /* enlarge our value buffer by a suitable margin if needed */
+ if (upto + len > value_size) {
+ value_size = (upto + len) + 500;
+ value = realloc(value, value_size);
+ if (!value) {
+ fprintf(stderr, "Out of mmory: cannot alloc "
+ "%d bytes\n", value_size);
+ return -1;
+ }
+ }
+
+ ptr = value + upto;
+ if (disp->type == 's') {
+ memcpy(ptr, *arg, len);
+ if (disp->verbose)
+ fprintf(stderr, "\tstring: '%s'\n", ptr);
+ } else {
+ int *iptr = (int *)ptr;
+ sscanf(*arg, fmt, &ival);
+ if (len == 4)
+ *iptr = cpu_to_fdt32(ival);
+ else
+ *ptr = (uint8_t)ival;
+ if (disp->verbose) {
+ fprintf(stderr, "\t%s: %d\n",
+ disp->size == 1 ? "byte" :
+ disp->size == 2 ? "short" : "int",
+ ival);
+ }
+ }
+ }
+ *value_len = upto;
+ *valuep = value;
+ if (disp->verbose)
+ fprintf(stderr, "Value size %d\n", upto);
+ return 0;
+}
+
+static int store_key_value(void *blob, const char *node_name,
+ const char *property, const char *buf, int len)
+{
+ int node;
+ int err;
+
+ node = fdt_path_offset(blob, node_name);
+ if (node < 0) {
+ report_error(node_name, -1, node);
+ return -1;
+ }
+
+ err = fdt_setprop(blob, node, property, buf, len);
+ if (err) {
+ report_error(property, -1, err);
+ return -1;
+ }
+ return 0;
+}
+
+/**
+ * Create paths as needed for all components of a path
+ *
+ * Any components of the path that do not exist are created. Errors are
+ * reported.
+ *
+ * @param blob FDT blob to write into
+ * @param in_path Path to process
+ * @return 0 if ok, -1 on error
+ */
+static int create_paths(void *blob, const char *in_path)
+{
+ const char *path = in_path;
+ const char *sep;
+ int node, offset = 0;
+
+ /* skip leading '/' */
+ while (*path == '/')
+ path++;
+
+ for (sep = path; *sep; path = sep + 1, offset = node) {
+ /* equivalent to strchrnul(), but it requires _GNU_SOURCE */
+ sep = strchr(path, '/');
+ if (!sep)
+ sep = path + strlen(path);
+
+ node = fdt_subnode_offset_namelen(blob, offset, path,
+ sep - path);
+ if (node == -FDT_ERR_NOTFOUND) {
+ node = fdt_add_subnode_namelen(blob, offset, path,
+ sep - path);
+ }
+ if (node < 0) {
+ report_error(path, sep - path, node);
+ return -1;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * Create a new node in the fdt.
+ *
+ * This will overwrite the node_name string. Any error is reported.
+ *
+ * TODO: Perhaps create fdt_path_offset_namelen() so we don't need to do this.
+ *
+ * @param blob FDT blob to write into
+ * @param node_name Name of node to create
+ * @return new node offset if found, or -1 on failure
+ */
+static int create_node(void *blob, const char *node_name)
+{
+ int node = 0;
+ char *p;
+
+ p = strrchr(node_name, '/');
+ if (!p) {
+ report_error(node_name, -1, -FDT_ERR_BADPATH);
+ return -1;
+ }
+ *p = '\0';
+
+ if (p > node_name) {
+ node = fdt_path_offset(blob, node_name);
+ if (node < 0) {
+ report_error(node_name, -1, node);
+ return -1;
+ }
+ }
+
+ node = fdt_add_subnode(blob, node, p + 1);
+ if (node < 0) {
+ report_error(p + 1, -1, node);
+ return -1;
+ }
+
+ return 0;
+}
+
+static int do_fdtput(struct display_info *disp, const char *filename,
+ char **arg, int arg_count)
+{
+ char *value;
+ char *blob;
+ int len, ret = 0;
+
+ blob = utilfdt_read(filename);
+ if (!blob)
+ return -1;
+
+ switch (disp->oper) {
+ case OPER_WRITE_PROP:
+ /*
+ * Convert the arguments into a single binary value, then
+ * store them into the property.
+ */
+ assert(arg_count >= 2);
+ if (disp->auto_path && create_paths(blob, *arg))
+ return -1;
+ if (encode_value(disp, arg + 2, arg_count - 2, &value, &len) ||
+ store_key_value(blob, *arg, arg[1], value, len))
+ ret = -1;
+ break;
+ case OPER_CREATE_NODE:
+ for (; ret >= 0 && arg_count--; arg++) {
+ if (disp->auto_path)
+ ret = create_paths(blob, *arg);
+ else
+ ret = create_node(blob, *arg);
+ }
+ break;
+ }
+ if (ret >= 0)
+ ret = utilfdt_write(filename, blob);
+
+ free(blob);
+ return ret;
+}
+
+static const char *usage_msg =
+ "fdtput - write a property value to a device tree\n"
+ "\n"
+ "The command line arguments are joined together into a single value.\n"
+ "\n"
+ "Usage:\n"
+ " fdtput <options> <dt file> <node> <property> [<value>...]\n"
+ " fdtput -c <options> <dt file> [<node>...]\n"
+ "Options:\n"
+ "\t-c\t\tCreate nodes if they don't already exist\n"
+ "\t-p\t\tAutomatically create nodes as needed for the node path\n"
+ "\t-t <type>\tType of data\n"
+ "\t-v\t\tVerbose: display each value decoded from command line\n"
+ "\t-h\t\tPrint this help\n\n"
+ USAGE_TYPE_MSG;
+
+static void usage(const char *msg)
+{
+ if (msg)
+ fprintf(stderr, "Error: %s\n\n", msg);
+
+ fprintf(stderr, "%s", usage_msg);
+ exit(2);
+}
+
+int main(int argc, char *argv[])
+{
+ struct display_info disp;
+ char *filename = NULL;
+
+ memset(&disp, '\0', sizeof(disp));
+ disp.size = -1;
+ disp.oper = OPER_WRITE_PROP;
+ for (;;) {
+ int c = getopt(argc, argv, "chpt:v");
+ if (c == -1)
+ break;
+
+ /*
+ * TODO: add options to:
+ * - delete property
+ * - delete node (optionally recursively)
+ * - rename node
+ * - pack fdt before writing
+ * - set amount of free space when writing
+ * - expand fdt if value doesn't fit
+ */
+ switch (c) {
+ case 'c':
+ disp.oper = OPER_CREATE_NODE;
+ break;
+ case 'h':
+ case '?':
+ usage(NULL);
+ case 'p':
+ disp.auto_path = 1;
+ break;
+ case 't':
+ if (utilfdt_decode_type(optarg, &disp.type,
+ &disp.size))
+ usage("Invalid type string");
+ break;
+
+ case 'v':
+ disp.verbose = 1;
+ break;
+ }
+ }
+
+ if (optind < argc)
+ filename = argv[optind++];
+ if (!filename)
+ usage("Missing filename");
+
+ argv += optind;
+ argc -= optind;
+
+ if (disp.oper == OPER_WRITE_PROP) {
+ if (argc < 1)
+ usage("Missing node");
+ if (argc < 2)
+ usage("Missing property");
+ }
+
+ if (do_fdtput(&disp, filename, argv, argc))
+ return 1;
+ return 0;
+}