backlight: Remove fb_blank from struct backlight_properties

Remove the field fb_blank from struct backlight_properties and remove
all code that still sets or reads it. Backlight blank status is now
tracked exclusively in struct backlight_properties.state.

The core backlight code keeps the fb_blank and state fields in sync,
but doesn't do anything else with fb_blank. Several drivers initialize
fb_blank to FB_BLANK_UNBLANK to enable the backlight. This is already
the default for the state field. So we can delete the fb_blank code
from core and drivers and rely on the state field.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Flavio Suligoi <f.suligoi@asem.it>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Claudiu Beznea <claudiu.beznea@tuxon.dev>
Tested-by: Flavio Suligoi <f.suligoi@asem.it>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/20240319093915.31778-7-tzimmermann@suse.de
Signed-off-by: Lee Jones <lee@kernel.org>

Author: Thomas Zimmermann

drivers/video/backlight/backlight.c

@@ -118,14 +118,12 @@ static int fb_notifier_callback(struct notifier_block *self,
 		bd->fb_bl_on[node] = true;
 		if (!bd->use_count++) {
 			bd->props.state &= ~BL_CORE_FBBLANK;
-			bd->props.fb_blank = FB_BLANK_UNBLANK;
 			backlight_update_status(bd);
 		}
 	} else if (fb_blank != FB_BLANK_UNBLANK && bd->fb_bl_on[node]) {
 		bd->fb_bl_on[node] = false;
 		if (!(--bd->use_count)) {
 			bd->props.state |= BL_CORE_FBBLANK;
-			bd->props.fb_blank = fb_blank;
 			backlight_update_status(bd);
 		}
 	}

drivers/video/backlight/mp3309c.c

@@ -363,7 +363,6 @@ static int mp3309c_probe(struct i2c_client *client)
 	props.scale = BACKLIGHT_SCALE_LINEAR;
 	props.type = BACKLIGHT_RAW;
 	props.power = FB_BLANK_UNBLANK;
-	props.fb_blank = FB_BLANK_UNBLANK;
 	chip->bl = devm_backlight_device_register(dev, "mp3309c", dev, chip,
 						  &mp3309c_bl_ops, &props);
 	if (IS_ERR(chip->bl))

drivers/video/backlight/omap1_bl.c

@@ -139,7 +139,6 @@ static int omapbl_probe(struct platform_device *pdev)
 
 	omap_cfg_reg(PWL);	/* Conflicts with UART3 */
 
-	dev->props.fb_blank = FB_BLANK_UNBLANK;
 	dev->props.brightness = pdata->default_intensity;
 	omapbl_update_status(dev);
 

drivers/video/fbdev/atmel_lcdfb.c

@@ -153,7 +153,6 @@ static void init_backlight(struct atmel_lcdfb_info *sinfo)
 	sinfo->backlight = bl;
 
 	bl->props.power = FB_BLANK_UNBLANK;
-	bl->props.fb_blank = FB_BLANK_UNBLANK;
 	bl->props.brightness = atmel_bl_get_brightness(bl);
 }
 

drivers/video/fbdev/omap2/omapfb/displays/panel-dsi-cm.c

@@ -1215,7 +1215,6 @@ static int dsicm_probe(struct platform_device *pdev)
 
 		ddata->bldev = bldev;
 
-		bldev->props.fb_blank = FB_BLANK_UNBLANK;
 		bldev->props.power = FB_BLANK_UNBLANK;
 		bldev->props.brightness = 255;
 

drivers/video/fbdev/omap2/omapfb/displays/panel-sony-acx565akm.c

@@ -753,7 +753,6 @@ static int acx565akm_probe(struct spi_device *spi)
 	}
 
 	memset(&props, 0, sizeof(props));
-	props.fb_blank = FB_BLANK_UNBLANK;
 	props.power = FB_BLANK_UNBLANK;
 	props.type = BACKLIGHT_RAW;
 

include/linux/backlight.h

@@ -218,25 +218,6 @@ struct backlight_properties {
 	 */
 	int power;
 
-	/**
-	 * @fb_blank: The power state from the FBIOBLANK ioctl.
-	 *
-	 * When the FBIOBLANK ioctl is called @fb_blank is set to the
-	 * blank parameter and the update_status() operation is called.
-	 *
-	 * When the backlight device is enabled @fb_blank is set
-	 * to FB_BLANK_UNBLANK. When the backlight device is disabled
-	 * @fb_blank is set to FB_BLANK_POWERDOWN.
-	 *
-	 * Backlight drivers should avoid using this property. It has been
-	 * replaced by state & BL_CORE_FBLANK (although most drivers should
-	 * use backlight_is_blank() as the preferred means to get the blank
-	 * state).
-	 *
-	 * fb_blank is deprecated and will be removed.
-	 */
-	int fb_blank;
-
 	/**
 	 * @type: The type of backlight supported.
 	 *
@@ -366,7 +347,6 @@ static inline int backlight_enable(struct backlight_device *bd)
 		return 0;
 
 	bd->props.power = FB_BLANK_UNBLANK;
-	bd->props.fb_blank = FB_BLANK_UNBLANK;
 	bd->props.state &= ~BL_CORE_FBBLANK;
 
 	return backlight_update_status(bd);
@@ -382,7 +362,6 @@ static inline int backlight_disable(struct backlight_device *bd)
 		return 0;
 
 	bd->props.power = FB_BLANK_POWERDOWN;
-	bd->props.fb_blank = FB_BLANK_POWERDOWN;
 	bd->props.state |= BL_CORE_FBBLANK;
 
 	return backlight_update_status(bd);
@@ -395,15 +374,13 @@ static inline int backlight_disable(struct backlight_device *bd)
  * Display is expected to be blank if any of these is true::
  *
  *   1) if power in not UNBLANK
- *   2) if fb_blank is not UNBLANK
- *   3) if state indicate BLANK or SUSPENDED
+ *   2) if state indicate BLANK or SUSPENDED
  *
  * Returns true if display is expected to be blank, false otherwise.
  */
 static inline bool backlight_is_blank(const struct backlight_device *bd)
 {
 	return bd->props.power != FB_BLANK_UNBLANK ||
-	       bd->props.fb_blank != FB_BLANK_UNBLANK ||
 	       bd->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK);
 }