]> git.ipfire.org Git - thirdparty/kernel/linux.git/commitdiff
w1: ds2406: use crc16() instead of crc16_byte() loop
authorEric Biggers <ebiggers@google.com>
Tue, 13 May 2025 02:21:14 +0000 (19:21 -0700)
committerEric Biggers <ebiggers@google.com>
Wed, 14 May 2025 03:37:16 +0000 (20:37 -0700)
Instead of looping through each byte and calling crc16_byte(), instead
just call crc16() on the whole buffer.  No functional change.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20250513022115.39109-2-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
drivers/w1/slaves/w1_ds2406.c

index 1cae9b243ff87f0013e55c7aa51cd1798741e9ca..76026d6151111ca6e8cc50723567a780f7c38d85 100644 (file)
@@ -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;