Because period and duty cycle are defined in the PWM framework structs as ints with units of nanoseconds, the maximum time duration that can be set is limited to ~2.147 seconds. Redefining them as u64 values will enable larger time durations to be set.
As a first step, prepare drivers to handle the switch to u64 period and duty_cycle by replacing division operations involving pwm period and duty cycle with their 64-bit equivalents as appropriate. The actual switch to u64 period and duty_cycle follows as a separate patch. Where the dividend is 64-bit but the divisor is 32-bit, use *_ULL macros: - DIV_ROUND_UP_ULL - DIV_ROUND_CLOSEST_ULL - div_u64 Where the divisor is 64-bit (dividend may be 32-bit or 64-bit), use DIV64_* macros: - DIV64_U64_ROUND_CLOSEST - div64_u64 Cc: Lee Jones <[email protected]> Cc: Daniel Thompson <[email protected]> Cc: Jingoo Han <[email protected]> Cc: Bartlomiej Zolnierkiewicz <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Signed-off-by: Guru Das Srinagesh <[email protected]> --- drivers/video/backlight/pwm_bl.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c index efb4efc..3e5dbcf 100644 --- a/drivers/video/backlight/pwm_bl.c +++ b/drivers/video/backlight/pwm_bl.c @@ -625,7 +625,8 @@ static int pwm_backlight_probe(struct platform_device *pdev) pb->scale = data->max_brightness; } - pb->lth_brightness = data->lth_brightness * (state.period / pb->scale); + pb->lth_brightness = data->lth_brightness * (div_u64(state.period, + pb->scale)); props.type = BACKLIGHT_RAW; props.max_brightness = data->max_brightness; -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project _______________________________________________ dri-devel mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/dri-devel
