From: Ville Syrjälä Date: Wed, 2 Mar 2016 15:22:18 +0000 (+0200) Subject: drm/i915: Use DIV_ROUND_CLOSEST for PWM calculations X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=37f2248e3d422f0463800b574ea9288ede97cea2;p=openwrt%2Fstaging%2Fblogic.git drm/i915: Use DIV_ROUND_CLOSEST for PWM calculations Supposedly we would want to get the PWM output as close as possible to the target, so let's round to closest. Cc: Jani Nikula Suggested-by: Jani Nikula Signed-off-by: Ville Syrjälä Link: http://patchwork.freedesktop.org/patch/msgid/1456932138-14004-7-git-send-email-ville.syrjala@linux.intel.com Reviewed-by: Jani Nikula --- diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c index 5cf377507162..0fe059bc7d80 100644 --- a/drivers/gpu/drm/i915/intel_panel.c +++ b/drivers/gpu/drm/i915/intel_panel.c @@ -1240,7 +1240,7 @@ static void intel_backlight_device_unregister(struct intel_connector *connector) */ static u32 bxt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz) { - return KHz(19200) / pwm_freq_hz; + return DIV_ROUND_CLOSEST(KHz(19200), pwm_freq_hz); } /* @@ -1258,7 +1258,7 @@ static u32 spt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz) else mul = 16; - return MHz(24) / (pwm_freq_hz * mul); + return DIV_ROUND_CLOSEST(MHz(24), pwm_freq_hz * mul); } /* @@ -1281,7 +1281,7 @@ static u32 lpt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz) else clock = MHz(24); /* LPT:LP */ - return clock / (pwm_freq_hz * mul); + return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * mul); } /* @@ -1292,7 +1292,7 @@ static u32 pch_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz) { struct drm_i915_private *dev_priv = to_i915(connector->base.dev); - return KHz(dev_priv->rawclk_freq) / (pwm_freq_hz * 128); + return DIV_ROUND_CLOSEST(KHz(dev_priv->rawclk_freq), pwm_freq_hz * 128); } /* @@ -1313,7 +1313,7 @@ static u32 i9xx_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz) else clock = KHz(dev_priv->cdclk_freq); - return clock / (pwm_freq_hz * 32); + return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * 32); } /* @@ -1332,7 +1332,7 @@ static u32 i965_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz) else clock = KHz(dev_priv->cdclk_freq); - return clock / (pwm_freq_hz * 128); + return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * 128); } /* @@ -1356,7 +1356,7 @@ static u32 vlv_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz) mul = 128; } - return clock / (pwm_freq_hz * mul); + return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * mul); } static u32 get_backlight_max_vbt(struct intel_connector *connector)