| Message ID | 20200130014130.51313-1-natechancellor@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | e093e53f4f70b126ff63bc422e5135e934e35a1b |
| Headers | show |
| Series | power: avs: qcom-cpr: Avoid clang -Wsometimes-uninitialized in cpr_scale | expand |
Nathan Chancellor <natechancellor@gmail.com> writes: > Clang warns (trimmed for brevity): > > ../drivers/power/avs/qcom-cpr.c:570:13: warning: variable 'reg_mask' is > used uninitialized whenever 'if' condition is false > [-Wsometimes-uninitialized] > > ../drivers/power/avs/qcom-cpr.c:520:13: warning: variable 'new_uV' is > used uninitialized whenever 'if' condition is false > [-Wsometimes-uninitialized] > > Due to the fact that Clang's static analysis happens before any > optimization passes are taken into account, it cannot see that both > branches in the if statement must be taken because dir cannot be > something other than UP or DOWN due to the check at the top of this > function. Change the else if condition to else to fix this false > positive. > > Fixes: bf6910abf548 ("power: avs: Add support for CPR (Core Power Reduction)") > Link: https://github.com/ClangBuiltLinux/linux/issues/840 > Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Acked-by: Kevin Hilman <khilman@baylibre.com> Rafael, feel free to queue directly. Kevin
diff --git a/drivers/power/avs/qcom-cpr.c b/drivers/power/avs/qcom-cpr.c index 9192fb747653..e8831e4aee05 100644 --- a/drivers/power/avs/qcom-cpr.c +++ b/drivers/power/avs/qcom-cpr.c @@ -517,7 +517,7 @@ static int cpr_scale(struct cpr_drv *drv, enum voltage_change_dir dir) dev_dbg(drv->dev, "UP: -> new_uV: %d last_uV: %d perf state: %u\n", new_uV, last_uV, cpr_get_cur_perf_state(drv)); - } else if (dir == DOWN) { + } else { if (desc->clamp_timer_interval && error_steps < desc->down_threshold) { /* @@ -567,7 +567,7 @@ static int cpr_scale(struct cpr_drv *drv, enum voltage_change_dir dir) /* Disable auto nack down */ reg_mask = RBCPR_CTL_SW_AUTO_CONT_NACK_DN_EN; val = 0; - } else if (dir == DOWN) { + } else { /* Restore default threshold for UP */ reg_mask = RBCPR_CTL_UP_THRESHOLD_MASK; reg_mask <<= RBCPR_CTL_UP_THRESHOLD_SHIFT;
Clang warns (trimmed for brevity): ../drivers/power/avs/qcom-cpr.c:570:13: warning: variable 'reg_mask' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized] ../drivers/power/avs/qcom-cpr.c:520:13: warning: variable 'new_uV' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized] Due to the fact that Clang's static analysis happens before any optimization passes are taken into account, it cannot see that both branches in the if statement must be taken because dir cannot be something other than UP or DOWN due to the check at the top of this function. Change the else if condition to else to fix this false positive. Fixes: bf6910abf548 ("power: avs: Add support for CPR (Core Power Reduction)") Link: https://github.com/ClangBuiltLinux/linux/issues/840 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> --- drivers/power/avs/qcom-cpr.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)