trng: Rename rand to trng_rand

The declaration for rand conflicts with the standard library declaration
so rename it from "rand" to "trng_rand". This has the benefit of making
it obvious when we're using the true random number generator.

For consistency, this also renames init_trng/exit_trng to
trng_init/trng_exit.

This is a reland of commit a6b0b3554f59cc9b0c4aae9bff7dff075f2089a9.

BRANCH=none
BUG=b:234181908, b:237344361
TEST=./util/compare_build.sh -b all -j 120
     => MATCH
TEST=emerge-hatch ec-utils-test

Signed-off-by: Tom Hughes <tomhughes@chromium.org>
Change-Id: Ic26890572cb9865275c866b65b0532c5ab029865
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3738978
Reviewed-by: Jack Rosenthal <jrosenth@chromium.org>
Reviewed-by: Bobby Casey <bobbycasey@google.com>

2 files changed, 14 insertions, 14 deletions

diff --git a/chip/host/trng.c b/chip/host/trng.c
index d54983f3a1..e2c13d7d14 100644
--- a/chip/host/trng.c
+++ b/chip/host/trng.c
@@ -21,17 +21,17 @@
 
 static unsigned int seed;
 
-test_mockable void init_trng(void)
+test_mockable void trng_init(void)
 {
 	seed = 0;
 	srand(seed);
 }
 
-test_mockable void exit_trng(void)
+test_mockable void trng_exit(void)
 {
 }
 
-test_mockable void rand_bytes(void *buffer, size_t len)
+test_mockable void trng_rand_bytes(void *buffer, size_t len)
 {
 	uint8_t *b, *end;
 
diff --git a/chip/stm32/trng.c b/chip/stm32/trng.c
index 6927786c48..6538263add 100644
--- a/chip/stm32/trng.c
+++ b/chip/stm32/trng.c
@@ -15,7 +15,7 @@
 #include "trng.h"
 #include "util.h"
 
-uint32_t rand(void)
+uint32_t trng_rand(void)
 {
 	int tries = 300;
 	/* Wait for a valid random number */
@@ -28,10 +28,10 @@ uint32_t rand(void)
 	return STM32_RNG_DR;
 }
 
-test_mockable void rand_bytes(void *buffer, size_t len)
+test_mockable void trng_rand_bytes(void *buffer, size_t len)
 {
 	while (len) {
-		uint32_t number = rand();
+		uint32_t number = trng_rand();
 		size_t cnt = 4;
 		/* deal with the lack of alignment guarantee in the API */
 		uintptr_t align = (uintptr_t)buffer & 3;
@@ -47,7 +47,7 @@ test_mockable void rand_bytes(void *buffer, size_t len)
 	}
 }
 
-test_mockable void init_trng(void)
+test_mockable void trng_init(void)
 {
 #ifdef CHIP_FAMILY_STM32L4
 	/* Enable the 48Mhz internal RC oscillator */
@@ -84,7 +84,7 @@ test_mockable void init_trng(void)
 	STM32_RNG_CR |= STM32_RNG_CR_RNGEN;
 }
 
-test_mockable void exit_trng(void)
+test_mockable void trng_exit(void)
 {
 	STM32_RNG_CR &= ~STM32_RNG_CR_RNGEN;
 	STM32_RCC_AHB2ENR &= ~STM32_RCC_AHB2ENR_RNGEN;
@@ -107,9 +107,9 @@ static int command_rand(int argc, char **argv)
 {
 	uint8_t data[32];
 
-	init_trng();
-	rand_bytes(data, sizeof(data));
-	exit_trng();
+	trng_init();
+	trng_rand_bytes(data, sizeof(data));
+	trng_exit();
 
 	ccprintf("rand %ph\n", HEX_BUF(data, sizeof(data)));
 
@@ -130,9 +130,9 @@ static enum ec_status host_command_rand(struct host_cmd_handler_args *args)
 	if (num_rand_bytes > args->response_max)
 		return EC_RES_OVERFLOW;
 
-	init_trng();
-	rand_bytes(r->rand, num_rand_bytes);
-	exit_trng();
+	trng_init();
+	trng_rand_bytes(r->rand, num_rand_bytes);
+	trng_exit();
 
 	args->response_size = num_rand_bytes;