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Subject[PATCH] leds: mt6323: move period calculation
Date
From: Tom Rix <trix@redhat.com>

clang static analysis reports this problem

leds-mt6323.c:275:12: warning: Division by zero
duty_hw = MT6323_CAL_HW_DUTY(*delay_on, period);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This is because period can be 0.

period = *delay_on + *delay_off;

There is a later check that *delay_on/off are valid.

if (!*delay_on && !*delay_off) {
*delay_on = 500;
*delay_off = 500;
}

Setting the delay_on/off means period needs to be recalculated
anyway. So move the period statements after this check.

Fixes: 216ec6cc4c19 ("leds: Add LED support for MT6323 PMIC")

Signed-off-by: Tom Rix <trix@redhat.com>
---
drivers/leds/leds-mt6323.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/leds/leds-mt6323.c b/drivers/leds/leds-mt6323.c
index 2a13e3161bf4..7b240771e45b 100644
--- a/drivers/leds/leds-mt6323.c
+++ b/drivers/leds/leds-mt6323.c
@@ -248,15 +248,6 @@ static int mt6323_led_set_blink(struct led_classdev *cdev,
u8 duty_hw;
int ret;

- /*
- * Units are in ms, if over the hardware able
- * to support, fallback into software blink
- */
- period = *delay_on + *delay_off;
-
- if (period > MT6323_MAX_PERIOD)
- return -EINVAL;
-
/*
* LED subsystem requires a default user
* friendly blink pattern for the LED so using
@@ -268,6 +259,15 @@ static int mt6323_led_set_blink(struct led_classdev *cdev,
*delay_off = 500;
}

+ /*
+ * Units are in ms, if over the hardware able
+ * to support, fallback into software blink
+ */
+ period = *delay_on + *delay_off;
+
+ if (period > MT6323_MAX_PERIOD)
+ return -EINVAL;
+
/*
* Calculate duty_hw based on the percentage of period during
* which the led is ON.
--
2.18.1
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