Commit 0769ebe2 authored by Eric Biggers's avatar Eric Biggers
Browse files

w1: ds2406: use crc16() instead of crc16_byte() loop 



Instead of looping through each byte and calling crc16_byte(), instead
just call crc16() on the whole buffer.  No functional change.

Acked-by: default avatarKrzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: default avatarArd Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20250513022115.39109-2-ebiggers@kernel.org


Signed-off-by: default avatarEric Biggers <ebiggers@google.com>
parent e8d72b76

drivers/w1/slaves/w1_ds2406.c

+2 −10
Original line number Diff line number Diff line
@@ -29,8 +29,6 @@ static ssize_t w1_f12_read_state( 
{

	u8 w1_buf[6] = {W1_F12_FUNC_READ_STATUS, 7, 0, 0, 0, 0};

	struct w1_slave *sl = kobj_to_w1_slave(kobj);

	u16 crc = 0;

	int i;

	ssize_t rtnval = 1;



	if (off != 0)
@@ -47,9 +45,7 @@ static ssize_t w1_f12_read_state( 


	w1_write_block(sl->master, w1_buf, 3);

	w1_read_block(sl->master, w1_buf+3, 3);

	for (i = 0; i < 6; i++)

		crc = crc16_byte(crc, w1_buf[i]);

	if (crc == 0xb001) /* good read? */

	if (crc16(0, w1_buf, sizeof(w1_buf)) == 0xb001) /* good read? */

		*buf = ((w1_buf[3]>>5)&3)|0x30;

	else

		rtnval = -EIO;
@@ -66,8 +62,6 @@ static ssize_t w1_f12_write_output( 
{

	struct w1_slave *sl = kobj_to_w1_slave(kobj);

	u8 w1_buf[6] = {W1_F12_FUNC_WRITE_STATUS, 7, 0, 0, 0, 0};

	u16 crc = 0;

	int i;

	ssize_t rtnval = 1;



	if (count != 1 || off != 0)
@@ -83,9 +77,7 @@ static ssize_t w1_f12_write_output( 
	w1_buf[3] = (((*buf)&3)<<5)|0x1F;

	w1_write_block(sl->master, w1_buf, 4);

	w1_read_block(sl->master, w1_buf+4, 2);

	for (i = 0; i < 6; i++)

		crc = crc16_byte(crc, w1_buf[i]);

	if (crc == 0xb001) /* good read? */

	if (crc16(0, w1_buf, sizeof(w1_buf)) == 0xb001) /* good read? */

		w1_write_8(sl->master, 0xFF);

	else

		rtnval = -EIO;