[PATCH 5.10.y 1/2] auxdisplay: Move init_display to hd44780_common

[Sasha Levin <sashal@kernel.org>]

From: Lars Poeschel <poeschel@lemonage.de>

[ Upstream commit 01ec46dfa633a52ccfe38d4a194460d6adb2ba00 ]

The init_display function is moved over to hd44780_common. charlcd uses
it via its ops function pointer and drivers initialize the ops with the
common hd44780_common_init_display function.

Reviewed-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Lars Poeschel <poeschel@lemonage.de>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

[ stable 5.10: The hd44780_common infrastructure and the prerequisite
  refactoring series are not present. Drop the init_display move and carry
  only the charlcd backlight enum normalization needed by the follow-up fix. ]

[ sashal: Reduced backport -- upstream 01ec46dfa633a touches 6 file(s), this
  backport carries 2. Not backported here:
  drivers/auxdisplay/hd44780.c
  drivers/auxdisplay/hd44780_common.c
  drivers/auxdisplay/hd44780_common.h
  drivers/auxdisplay/panel.c
  This note is generated from the file lists only; see the resolution record
  for the reasoning. ]

Stable-dep-of: e3e3bf40916c ("auxdisplay: charlcd: cancel backlight work on registration failure")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/auxdisplay/charlcd.c | 6 +++---
 drivers/auxdisplay/charlcd.h | 5 +++++
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/auxdisplay/charlcd.c b/drivers/auxdisplay/charlcd.c
index 5aee0f5463514..e74e25ff030b2 100644
--- a/drivers/auxdisplay/charlcd.c
+++ b/drivers/auxdisplay/charlcd.c
@@ -124,7 +124,7 @@ static void charlcd_bl_off(struct work_struct *work)
 	if (priv->bl_tempo) {
 		priv->bl_tempo = false;
 		if (!(priv->flags & LCD_FLAG_L))
-			priv->lcd.ops->backlight(&priv->lcd, 0);
+			priv->lcd.ops->backlight(&priv->lcd, CHARLCD_OFF);
 	}
 	mutex_unlock(&priv->bl_tempo_lock);
 }
@@ -141,7 +141,7 @@ void charlcd_poke(struct charlcd *lcd)
 
 	mutex_lock(&priv->bl_tempo_lock);
 	if (!priv->bl_tempo && !(priv->flags & LCD_FLAG_L))
-		lcd->ops->backlight(lcd, 1);
+		lcd->ops->backlight(lcd, CHARLCD_ON);
 	priv->bl_tempo = true;
 	schedule_delayed_work(&priv->bl_work, LCD_BL_TEMPO_PERIOD * HZ);
 	mutex_unlock(&priv->bl_tempo_lock);
@@ -862,7 +862,7 @@ int charlcd_unregister(struct charlcd *lcd)
 	the_charlcd = NULL;
 	if (lcd->ops->backlight) {
 		cancel_delayed_work_sync(&priv->bl_work);
-		priv->lcd.ops->backlight(&priv->lcd, 0);
+		priv->lcd.ops->backlight(&priv->lcd, CHARLCD_OFF);
 	}
 
 	return 0;
diff --git a/drivers/auxdisplay/charlcd.h b/drivers/auxdisplay/charlcd.h
index 00911ad0f3deb..993f03652f2a8 100644
--- a/drivers/auxdisplay/charlcd.h
+++ b/drivers/auxdisplay/charlcd.h
@@ -9,6 +9,11 @@
 #ifndef _CHARLCD_H
 #define _CHARLCD_H
 
+enum charlcd_onoff {
+	CHARLCD_OFF = 0,
+	CHARLCD_ON,
+};
+
 struct charlcd {
 	const struct charlcd_ops *ops;
 	const unsigned char *char_conv;	/* Optional */
-- 
2.53.0