[PATCH 1/8] Documentation/spi/spidev_test.c: use one rx buffer

From: Joshua Clayton
Date: Tue Nov 17 2015 - 10:25:27 EST


default_rx and rx are needlessly different.
Use one buffer, local to transmit()

Signed-off-by: Joshua Clayton <stillcompiling@xxxxxxxxx>
---
Documentation/spi/spidev_test.c | 13 +++++--------
1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/Documentation/spi/spidev_test.c b/Documentation/spi/spidev_test.c
index 135b3f5..dfe8f47 100644
--- a/Documentation/spi/spidev_test.c
+++ b/Documentation/spi/spidev_test.c
@@ -46,7 +46,6 @@ uint8_t default_tx[] = {
0xF0, 0x0D,
};

-uint8_t default_rx[ARRAY_SIZE(default_tx)] = {0, };
char *input_tx;

static void hex_dump(const void *src, size_t length, size_t line_size, char *prefix)
@@ -100,10 +99,10 @@ static int unescape(char *_dst, char *_src, size_t len)
return ret;
}

-static void transfer(int fd, uint8_t const *tx, uint8_t const *rx, size_t len)
+static void transfer(int fd, uint8_t const *tx, size_t len)
{
int ret;
-
+ uint8_t *rx = malloc(len);
struct spi_ioc_transfer tr = {
.tx_buf = (unsigned long)tx,
.rx_buf = (unsigned long)rx,
@@ -135,6 +134,7 @@ static void transfer(int fd, uint8_t const *tx, uint8_t const *rx, size_t len)
if (verbose)
hex_dump(tx, len, 32, "TX");
hex_dump(rx, len, 32, "RX");
+ free(rx);
}

static void print_usage(const char *prog)
@@ -254,7 +254,6 @@ int main(int argc, char *argv[])
int ret = 0;
int fd;
uint8_t *tx;
- uint8_t *rx;
int size;

parse_opts(argc, argv);
@@ -303,13 +302,11 @@ int main(int argc, char *argv[])
if (input_tx) {
size = strlen(input_tx+1);
tx = malloc(size);
- rx = malloc(size);
size = unescape((char *)tx, input_tx, size);
- transfer(fd, tx, rx, size);
- free(rx);
+ transfer(fd, tx, size);
free(tx);
} else {
- transfer(fd, default_tx, default_rx, sizeof(default_tx));
+ transfer(fd, default_tx, sizeof(default_tx));
}

close(fd);
--
2.5.0

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