[PATCH v13 09/11] backlight: pwm_bl: Use 64-bit division function

[PATCH v13 09/11] backlight: pwm_bl: Use 64-bit division function

[Guru Das Srinagesh]

Since the PWM framework is switching struct pwm_state.period's datatype
to u64, prepare for this transition by using div_u64 to handle a 64-bit
dividend instead of a straight division operation.

Cc: Lee Jones <lee.jones@linaro.org>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Jingoo Han <jingoohan1@gmail.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: linux-pwm@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linux-fbdev@vger.kernel.org

Signed-off-by: Guru Das Srinagesh <gurus@codeaurora.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
---
 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 82b8d75..464baad 100644
--- a/drivers/video/backlight/pwm_bl.c
+++ b/drivers/video/backlight/pwm_bl.c
@@ -606,7 +606,8 @@ 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

Re: [PATCH v13 09/11] backlight: pwm_bl: Use 64-bit division function

[Lee Jones]

On Tue, 21 Apr 2020, Guru Das Srinagesh wrote:

> Since the PWM framework is switching struct pwm_state.period's datatype
> to u64, prepare for this transition by using div_u64 to handle a 64-bit
> dividend instead of a straight division operation.
> 
> Cc: Lee Jones <lee.jones@linaro.org>
> Cc: Daniel Thompson <daniel.thompson@linaro.org>
> Cc: Jingoo Han <jingoohan1@gmail.com>
> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
> Cc: linux-pwm@vger.kernel.org
> Cc: dri-devel@lists.freedesktop.org
> Cc: linux-fbdev@vger.kernel.org
> 
> Signed-off-by: Guru Das Srinagesh <gurus@codeaurora.org>
> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>

Acked-by: Lee Jones <lee.jones@linaro.org>

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
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