diff options
author | Bjorn Andersson <quic_bjorande@quicinc.com> | 2023-05-15 09:26:04 -0700 |
---|---|---|
committer | Vinod Koul <vkoul@kernel.org> | 2023-05-30 21:34:38 +0530 |
commit | ee96c4b7ad650eba07a1c67ceae23222aa3c4d52 (patch) | |
tree | 088d58fa610930dde5f535bd745974348c56e23e | |
parent | d2636e97f58928c879a79c04f827fd26099be31c (diff) |
leds: qcom-lpg: Fix PWM period limitslaptop/6.4
The introduction of high resolution PWM support changed the order of the
operations in the calculation of min and max period. The result in both
divisions is in most cases a truncation to 0, which limits the period to
the range of [0, 0].
Both numerators (and denominators) are within 64 bits, so the whole
expression can be put directly into the div64_u64, instead of doing it
partially.
Fixes: b00d2ed37617 ("leds: rgb: leds-qcom-lpg: Add support for high resolution PWM")
Reviewed-by: Caleb Connolly <caleb.connolly@linaro.org>
Tested-by: Steev Klimaszewski <steev@kali.org>
Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com>
Link: https://lore.kernel.org/r/20230515162604.649203-1-quic_bjorande@quicinc.com
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
-rw-r--r-- | drivers/leds/rgb/leds-qcom-lpg.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/leds/rgb/leds-qcom-lpg.c b/drivers/leds/rgb/leds-qcom-lpg.c index 55a037234df1..1c849814a491 100644 --- a/drivers/leds/rgb/leds-qcom-lpg.c +++ b/drivers/leds/rgb/leds-qcom-lpg.c @@ -312,14 +312,14 @@ static int lpg_calc_freq(struct lpg_channel *chan, uint64_t period) max_res = LPG_RESOLUTION_9BIT; } - min_period = (u64)NSEC_PER_SEC * - div64_u64((1 << pwm_resolution_arr[0]), clk_rate_arr[clk_len - 1]); + min_period = div64_u64((u64)NSEC_PER_SEC * (1 << pwm_resolution_arr[0]), + clk_rate_arr[clk_len - 1]); if (period <= min_period) return -EINVAL; /* Limit period to largest possible value, to avoid overflows */ - max_period = (u64)NSEC_PER_SEC * max_res * LPG_MAX_PREDIV * - div64_u64((1 << LPG_MAX_M), 1024); + max_period = div64_u64((u64)NSEC_PER_SEC * max_res * LPG_MAX_PREDIV * (1 << LPG_MAX_M), + 1024); if (period > max_period) period = max_period; |