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-rw-r--r--drivers/of/module.c74
1 files changed, 74 insertions, 0 deletions
diff --git a/drivers/of/module.c b/drivers/of/module.c
new file mode 100644
index 0000000000..0e8aa974f0
--- /dev/null
+++ b/drivers/of/module.c
@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Linux kernel module helpers.
+ */
+
+#include <linux/of.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+
+ssize_t of_modalias(const struct device_node *np, char *str, ssize_t len)
+{
+ const char *compat;
+ char *c;
+ struct property *p;
+ ssize_t csize;
+ ssize_t tsize;
+
+ /* Name & Type */
+ /* %p eats all alphanum characters, so %c must be used here */
+ csize = snprintf(str, len, "of:N%pOFn%c%s", np, 'T',
+ of_node_get_device_type(np));
+ tsize = csize;
+ len -= csize;
+ if (str)
+ str += csize;
+
+ of_property_for_each_string(np, "compatible", p, compat) {
+ csize = strlen(compat) + 1;
+ tsize += csize;
+ if (csize > len)
+ continue;
+
+ csize = snprintf(str, len, "C%s", compat);
+ for (c = str; c; ) {
+ c = strchr(c, ' ');
+ if (c)
+ *c++ = '_';
+ }
+ len -= csize;
+ str += csize;
+ }
+
+ return tsize;
+}
+
+int of_request_module(const struct device_node *np)
+{
+ char *str;
+ ssize_t size;
+ int ret;
+
+ if (!np)
+ return -ENODEV;
+
+ size = of_modalias(np, NULL, 0);
+ if (size < 0)
+ return size;
+
+ /* Reserve an additional byte for the trailing '\0' */
+ size++;
+
+ str = kmalloc(size, GFP_KERNEL);
+ if (!str)
+ return -ENOMEM;
+
+ of_modalias(np, str, size);
+ str[size - 1] = '\0';
+ ret = request_module(str);
+ kfree(str);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(of_request_module);