[PATCH net-next v2] ptp: ocp: Avoid operator precedence warning in ptp_ocp_summary_show()

From: Nathan Chancellor
Date: Fri Sep 17 2021 - 00:55:19 EST


Clang warns twice:

drivers/ptp/ptp_ocp.c:2065:16: error: operator '?:' has lower precedence
than '&'; '&' will be evaluated first
[-Werror,-Wbitwise-conditional-parentheses]
on & map ? " ON" : "OFF", src);
~~~~~~~~ ^
drivers/ptp/ptp_ocp.c:2065:16: note: place parentheses around the '&'
expression to silence this warning
on & map ? " ON" : "OFF", src);
^
( )
drivers/ptp/ptp_ocp.c:2065:16: note: place parentheses around the '?:'
expression to evaluate it first
on & map ? " ON" : "OFF", src);
^

on and map are both booleans so this should be a logical AND, which
clears up the operator precedence issue.

Fixes: a62a56d04e63 ("ptp: ocp: Enable 4th timestamper / PPS generator")
Link: https://github.com/ClangBuiltLinux/linux/issues/1457
Suggested-by: Jonathan Lemon <jonathan.lemon@xxxxxxxxx>
Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx>
---

v1 -> v2: https://lore.kernel.org/r/20210916194351.3860836-1-nathan@xxxxxxxxxx/

* Change fix from adding parentheses to moving from bitwise to logical
AND. Thanks to Jonathan for catching that both operands were boolean,
which I unfortunately missed.

drivers/ptp/ptp_ocp.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/ptp/ptp_ocp.c b/drivers/ptp/ptp_ocp.c
index 844b1401cc5d..c26708f486cf 100644
--- a/drivers/ptp/ptp_ocp.c
+++ b/drivers/ptp/ptp_ocp.c
@@ -2062,11 +2062,11 @@ ptp_ocp_summary_show(struct seq_file *s, void *data)
on = ioread32(&ts_reg->enable);
map = !!(bp->pps_req_map & OCP_REQ_TIMESTAMP);
seq_printf(s, "%7s: %s, src: %s\n", "TS3",
- on & map ? " ON" : "OFF", src);
+ on && map ? " ON" : "OFF", src);

map = !!(bp->pps_req_map & OCP_REQ_PPS);
seq_printf(s, "%7s: %s, src: %s\n", "PPS",
- on & map ? " ON" : "OFF", src);
+ on && map ? " ON" : "OFF", src);
}

if (bp->irig_out) {

base-commit: 8dc84dcd7f74b50f81de3dbf6f6b5b146e3a8eea
--
2.33.0