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authorUwe Kleine-König <u.kleine-koenig@pengutronix.de>2019-01-07 20:49:37 +0100
committerThierry Reding <thierry.reding@gmail.com>2019-01-10 09:32:23 +0100
commit309b32fb97d8cf0771373fb55e16b2852840c9aa (patch)
tree6ce2654c548f831cfd9938c9f632abe8a965823f /drivers/pwm
parentbfeffd155283772bbe78c6a05dec7c0128ee500c (diff)
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pwm: Don't use memcmp() to compare state variables
Given that struct pwm_state is sparse (at least on some platforms), variables of this type might represent the same state because all fields are pairwise identical but still memcmp() returns a difference because some of the unused bits are different. To prevent surprises compare member by member instead of the whole occupied memory. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Diffstat (limited to 'drivers/pwm')
-rw-r--r--drivers/pwm/core.c5
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index 1581f6ab1b1f..253a459fe0d8 100644
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -472,7 +472,10 @@ int pwm_apply_state(struct pwm_device *pwm, struct pwm_state *state)
state->duty_cycle > state->period)
return -EINVAL;
- if (!memcmp(state, &pwm->state, sizeof(*state)))
+ if (state->period == pwm->state.period &&
+ state->duty_cycle == pwm->state.duty_cycle &&
+ state->polarity == pwm->state.polarity &&
+ state->enabled == pwm->state.enabled)
return 0;
if (pwm->chip->ops->apply) {