On Thu, 2011-01-06 at 16:08 +0900, Paul Mundt wrote: > (Trying an alternate address for Richard, and adding Andrew to Cc..) > > On Thu, Dec 09, 2010 at 02:41:50PM +0100, Janusz Krzysztofik wrote: > > This patch extends the LED backlight tirgger driver with an option that > > allows > > for inverting the trigger output polarity. > > > > With the invertion option provided, I (ab)use the backlight trigger for > > driving a LED that indicates LCD display blank condtition on my Amstrad > > Delta > > videophone. Since the machine has no dedicated power LED, it was not > > possible > > to distinguish if the display was blanked, or the machine was turned off, > > without touching it. > > > > The invert sysfs control is patterned after a similiar function of the GPIO > > trigger driver. > > > > Created and tested against linux-2.6.36-rc5 on Amstrad Delta. > > Retested on linux-2.6.37-rc4. > > > > Signed-off-by: Janusz Krzysztofik <[email protected]> > > Cc: Richard Purdie <[email protected]>
Acked-by: Richard Purdie <[email protected]> I'll let Andrew take the patch though. > > --- > > > > Resent because I still can't see any response received, while yet another > > merge window is going to pass away soon. > > > > Applies cleanly on top of 2.6.37-rc4, so no need for yet another refresh. > > Only > > tried to clean up the commit message slightly - maybe my English is not > > good > > enough to bother with, if not the code? > > > > v1 -> v2 changes: > > - improve some conditional expressions to be more readable; thanks to Ralph > > Corderoy (from e3-hacking) and Lars-Peter Clausen for their suggestions, > > - refresh against linux-2.6.36-rc5. > > > > drivers/leds/ledtrig-backlight.c | 60 > > ++++++++++++++++++++++++++++++++++++--- > > 1 file changed, 56 insertions(+), 4 deletions(-) > > > > diff -upr linux-2.6.36-rc5.orig/drivers/leds/ledtrig-backlight.c > > linux-2.6.36-rc5/drivers/leds/ledtrig-backlight.c > > --- linux-2.6.36-rc5.orig/drivers/leds/ledtrig-backlight.c 2010-09-24 > > 15:35:13.000000000 +0200 > > +++ linux-2.6.36-rc5/drivers/leds/ledtrig-backlight.c 2010-10-03 > > 15:59:49.000000000 +0200 > > @@ -26,6 +26,7 @@ struct bl_trig_notifier { > > int brightness; > > int old_status; > > struct notifier_block notifier; > > + unsigned invert; > > }; > > > > static int fb_notifier_callback(struct notifier_block *p, > > @@ -36,23 +37,63 @@ static int fb_notifier_callback(struct n > > struct led_classdev *led = n->led; > > struct fb_event *fb_event = data; > > int *blank = fb_event->data; > > + int new_status = *blank ? BLANK : UNBLANK; > > > > switch (event) { > > case FB_EVENT_BLANK : > > - if (*blank && n->old_status == UNBLANK) { > > + if (new_status == n->old_status) > > + break; > > + > > + if ((n->old_status == UNBLANK) ^ n->invert) { > > n->brightness = led->brightness; > > led_set_brightness(led, LED_OFF); > > - n->old_status = BLANK; > > - } else if (!*blank && n->old_status == BLANK) { > > + } else { > > led_set_brightness(led, n->brightness); > > - n->old_status = UNBLANK; > > } > > + > > + n->old_status = new_status; > > + > > break; > > } > > > > return 0; > > } > > > > +static ssize_t bl_trig_invert_show(struct device *dev, > > + struct device_attribute *attr, char *buf) > > +{ > > + struct led_classdev *led = dev_get_drvdata(dev); > > + struct bl_trig_notifier *n = led->trigger_data; > > + > > + return sprintf(buf, "%s\n", n->invert ? "yes" : "no"); > > +} > > + > > +static ssize_t bl_trig_invert_store(struct device *dev, > > + struct device_attribute *attr, const char *buf, size_t num) > > +{ > > + struct led_classdev *led = dev_get_drvdata(dev); > > + struct bl_trig_notifier *n = led->trigger_data; > > + unsigned invert; > > + int ret; > > + > > + ret = sscanf(buf, "%u", &invert); > > + if (ret < 1) { > > + dev_err(dev, "invalid value\n"); > > + return -EINVAL; > > + } > > + > > + n->invert = !!invert; > > + > > + /* After inverting, we need to update the LED. */ > > + if ((n->old_status == BLANK) ^ n->invert) > > + led_set_brightness(led, LED_OFF); > > + else > > + led_set_brightness(led, n->brightness); > > + > > + return num; > > +} > > +static DEVICE_ATTR(invert, 0644, bl_trig_invert_show, > > bl_trig_invert_store); > > + > > static void bl_trig_activate(struct led_classdev *led) > > { > > int ret; > > @@ -66,6 +107,10 @@ static void bl_trig_activate(struct led_ > > return; > > } > > > > + ret = device_create_file(led->dev, &dev_attr_invert); > > + if (ret) > > + goto err_invert; > > + > > n->led = led; > > n->brightness = led->brightness; > > n->old_status = UNBLANK; > > @@ -74,6 +119,12 @@ static void bl_trig_activate(struct led_ > > ret = fb_register_client(&n->notifier); > > if (ret) > > dev_err(led->dev, "unable to register backlight trigger\n"); > > + > > + return; > > + > > +err_invert: > > + led->trigger_data = NULL; > > + kfree(n); > > } > > > > static void bl_trig_deactivate(struct led_classdev *led) > > @@ -82,6 +133,7 @@ static void bl_trig_deactivate(struct le > > (struct bl_trig_notifier *) led->trigger_data; > > > > if (n) { > > + device_remove_file(led->dev, &dev_attr_invert); > > fb_unregister_client(&n->notifier); > > kfree(n); > > } > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in > > the body of a message to [email protected] > > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
