| Message ID | 1341807700-7103-1-git-send-email-acourbot@nvidia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Jul 09, 2012 at 01:21:40PM +0900, Alexandre Courbot wrote: > pwm_backlight_update_status calls two callbacks before and after > applying the new PWM settings. However, the brightness scale is > completely changed in between if brightness levels are used. This patch > ensures that both callbacks are passed brightness values of the same > meaning. > > Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> > --- > drivers/video/backlight/pwm_bl.c | 12 +++++++----- > 1 file changed, 7 insertions(+), 5 deletions(-) I had to actually read this patch a number of times and then realized I was completely missing the context. Looking at the whole function makes it more obvious what you mean. However I think it'd be much clearer if we just passed the value of bl->props.brightness into the callbacks, that way we can avoid the additional variable. Thierry > > diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c > index 057389d..dd4d24d 100644 > --- a/drivers/video/backlight/pwm_bl.c > +++ b/drivers/video/backlight/pwm_bl.c > @@ -39,6 +39,7 @@ static int pwm_backlight_update_status(struct backlight_device *bl) > { > struct pwm_bl_data *pb = dev_get_drvdata(&bl->dev); > int brightness = bl->props.brightness; > + int pwm_brightness; > int max = bl->props.max_brightness; > > if (bl->props.power != FB_BLANK_UNBLANK) > @@ -55,13 +56,14 @@ static int pwm_backlight_update_status(struct backlight_device *bl) > pwm_disable(pb->pwm); > } else { > if (pb->levels) { > - brightness = pb->levels[brightness]; > + pwm_brightness = pb->levels[brightness]; > max = pb->levels[max]; > - } > + } else > + pwm_brightness = brightness; > > - brightness = pb->lth_brightness + > - (brightness * (pb->period - pb->lth_brightness) / max); > - pwm_config(pb->pwm, brightness, pb->period); > + pwm_brightness = pb->lth_brightness + > + (pwm_brightness * (pb->period - pb->lth_brightness) / max); > + pwm_config(pb->pwm, pwm_brightness, pb->period); > pwm_enable(pb->pwm); > } > > -- > 1.7.11.1 > >
On Monday, July 09, 2012 1:22 PM, Alexandre Courbot wrote: > pwm_backlight_update_status calls two callbacks before and after > applying the new PWM settings. However, the brightness scale is > completely changed in between if brightness levels are used. This patch > ensures that both callbacks are passed brightness values of the same > meaning. > > Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> > --- > drivers/video/backlight/pwm_bl.c | 12 +++++++----- > 1 file changed, 7 insertions(+), 5 deletions(-) > > diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c > index 057389d..dd4d24d 100644 > --- a/drivers/video/backlight/pwm_bl.c > +++ b/drivers/video/backlight/pwm_bl.c > @@ -39,6 +39,7 @@ static int pwm_backlight_update_status(struct backlight_device *bl) > { > struct pwm_bl_data *pb = dev_get_drvdata(&bl->dev); > int brightness = bl->props.brightness; > + int pwm_brightness; > int max = bl->props.max_brightness; > > if (bl->props.power != FB_BLANK_UNBLANK) > @@ -55,13 +56,14 @@ static int pwm_backlight_update_status(struct backlight_device *bl) > pwm_disable(pb->pwm); > } else { > if (pb->levels) { > - brightness = pb->levels[brightness]; > + pwm_brightness = pb->levels[brightness]; > max = pb->levels[max]; > - } > + } else > + pwm_brightness = brightness; Hi Alexandre Courbot, Please, use braces to keep the Coding Style. Refer to Documentation/CodingStyle as follow: 169 This does not apply if only one branch of a conditional statement is a single 170 statement; in the latter case use braces in both branches: 171 172 if (condition) { 173 do_this(); 174 do_that(); 175 } else { 176 otherwise(); 177 } Best regards, Jingoo Han > > - brightness = pb->lth_brightness + > - (brightness * (pb->period - pb->lth_brightness) / max); > - pwm_config(pb->pwm, brightness, pb->period); > + pwm_brightness = pb->lth_brightness + > + (pwm_brightness * (pb->period - pb->lth_brightness) / max); > + pwm_config(pb->pwm, pwm_brightness, pb->period); > pwm_enable(pb->pwm); > } > > -- > 1.7.11.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 07/09/2012 02:10 PM, Thierry Reding wrote: > I had to actually read this patch a number of times and then realized I > was completely missing the context. Looking at the whole function makes > it more obvious what you mean. > > However I think it'd be much clearer if we just passed the value of > bl->props.brightness into the callbacks, that way we can avoid the > additional variable. This won't work I'm afraid, as brightness can be modified prior to being passed to the callback function: if (bl->props.power != FB_BLANK_UNBLANK) brightness = 0; if (bl->props.fb_blank != FB_BLANK_UNBLANK) brightness = 0; if (pb->notify) brightness = pb->notify(pb->dev, brightness); Alex. -- To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c index 057389d..dd4d24d 100644 --- a/drivers/video/backlight/pwm_bl.c +++ b/drivers/video/backlight/pwm_bl.c @@ -39,6 +39,7 @@ static int pwm_backlight_update_status(struct backlight_device *bl) { struct pwm_bl_data *pb = dev_get_drvdata(&bl->dev); int brightness = bl->props.brightness; + int pwm_brightness; int max = bl->props.max_brightness; if (bl->props.power != FB_BLANK_UNBLANK) @@ -55,13 +56,14 @@ static int pwm_backlight_update_status(struct backlight_device *bl) pwm_disable(pb->pwm); } else { if (pb->levels) { - brightness = pb->levels[brightness]; + pwm_brightness = pb->levels[brightness]; max = pb->levels[max]; - } + } else + pwm_brightness = brightness; - brightness = pb->lth_brightness + - (brightness * (pb->period - pb->lth_brightness) / max); - pwm_config(pb->pwm, brightness, pb->period); + pwm_brightness = pb->lth_brightness + + (pwm_brightness * (pb->period - pb->lth_brightness) / max); + pwm_config(pb->pwm, pwm_brightness, pb->period); pwm_enable(pb->pwm); }
pwm_backlight_update_status calls two callbacks before and after applying the new PWM settings. However, the brightness scale is completely changed in between if brightness levels are used. This patch ensures that both callbacks are passed brightness values of the same meaning. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> --- drivers/video/backlight/pwm_bl.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)