Merge branch '2022-09-29-dm-core-support-multiple-device-trees-in-ofnode' into next

[platform/kernel/u-boot.git] / cmd / rng.c

diff --git a/cmd/rng.c b/cmd/rng.c
index 9747c11..81a2396 100644 (file)
--- a/cmd/rng.c
+++ b/cmd/rng.c
@@ -13,24 +13,38 @@
 
 static int do_rng(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
 {
-       size_t n = 0x40;
+       size_t n;
+       u8 buf[64];
+       int devnum;
        struct udevice *dev;
-       void *buf;
        int ret = CMD_RET_SUCCESS;
 
-       if (uclass_get_device(UCLASS_RNG, 0, &dev) || !dev) {
+       switch (argc) {
+       case 1:
+               devnum = 0;
+               n = 0x40;
+               break;
+       case 2:
+               devnum = hextoul(argv[1], NULL);
+               n = 0x40;
+               break;
+       case 3:
+               devnum = hextoul(argv[1], NULL);
+               n = hextoul(argv[2], NULL);
+               break;
+       default:
+               return CMD_RET_USAGE;
+       }
+
+       if (uclass_get_device_by_seq(UCLASS_RNG, devnum, &dev) || !dev) {
                printf("No RNG device\n");
                return CMD_RET_FAILURE;
        }
 
-       if (argc >= 2)
-               n = simple_strtoul(argv[1], NULL, 16);
+       if (!n)
+               return 0;
 
-       buf = malloc(n);
-       if (!buf) {
-               printf("Out of memory\n");
-               return CMD_RET_FAILURE;
-       }
+       n = min(n, sizeof(buf));
 
        if (dm_rng_read(dev, buf, n)) {
                printf("Reading RNG failed\n");
@@ -39,19 +53,17 @@ static int do_rng(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
                print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, buf, n);
        }
 
-       free(buf);
-
        return ret;
 }
 
 #ifdef CONFIG_SYS_LONGHELP
 static char rng_help_text[] =
-       "[n]\n"
-       "  - print n random bytes\n";
+       "[dev [n]]\n"
+       "  - print n random bytes(max 64) read from dev\n";
 #endif
 
 U_BOOT_CMD(
-       rng, 2, 0, do_rng,
+       rng, 3, 0, do_rng,
        "print bytes from the hardware random number generator",
        rng_help_text
 );