linux-kernel - [RFC PATCH 09/10] drm/panel: sony-acx565akm: Don't double-check enabled state in disable

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Message-ID: <20230804140605.RFC.9.I6a51b36831a5c7b2b82bccf8c550cf0d076aa541@changeid>
Date:   Fri,  4 Aug 2023 14:06:12 -0700
From:   Douglas Anderson <dianders@...omium.org>
To:     dri-devel@...ts.freedesktop.org, Maxime Ripard <mripard@...nel.org>
Cc:     Linus Walleij <linus.walleij@...aro.org>,
        Douglas Anderson <dianders@...omium.org>,
        Daniel Vetter <daniel@...ll.ch>,
        David Airlie <airlied@...il.com>,
        Neil Armstrong <neil.armstrong@...aro.org>,
        Sam Ravnborg <sam@...nborg.org>, linux-kernel@...r.kernel.org
Subject: [RFC PATCH 09/10] drm/panel: sony-acx565akm: Don't double-check enabled state in disable

As talked about in commit d2aacaf07395 ("drm/panel: Check for already
prepared/enabled in drm_panel"), we want to remove needless code from
panel drivers that was storing and double-checking the
prepared/enabled state. Even if someone was relying on the
double-check before, that double-check is now in the core and not
needed in individual drivers.

The acx565akm seems to do some unique stuff with the "enabled"
state. Specifically:
1. It seems to detect the enabled state based on how the bootloader
   left the panel.
2. It uses the enabled state to prevent certain sysfs files from
   accessing a disabled panel.

We'll leave the "enabled" state tracking for this. However, we can at
least get rid of the double-check when trying to disable. In order to
do this we use the new drm_panel_helper_shutdown() from remove() which
double-checks for us.

Signed-off-by: Douglas Anderson <dianders@...omium.org>
---

 drivers/gpu/drm/panel/panel-sony-acx565akm.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/panel/panel-sony-acx565akm.c b/drivers/gpu/drm/panel/panel-sony-acx565akm.c
index 3d6a286056a0..8a8326a94d72 100644
--- a/drivers/gpu/drm/panel/panel-sony-acx565akm.c
+++ b/drivers/gpu/drm/panel/panel-sony-acx565akm.c
@@ -30,6 +30,7 @@
 #include <drm/drm_connector.h>
 #include <drm/drm_modes.h>
 #include <drm/drm_panel.h>
+#include <drm/drm_panel_helper.h>

 #define CTRL_DISP_BRIGHTNESS_CTRL_ON		BIT(5)
 #define CTRL_DISP_AMBIENT_LIGHT_CTRL_ON		BIT(4)
@@ -454,9 +455,6 @@ static int acx565akm_power_on(struct acx565akm_panel *lcd)

 static void acx565akm_power_off(struct acx565akm_panel *lcd)
 {
-	if (!lcd->enabled)
-		return;
-
 	acx565akm_set_display_state(lcd, 0);
 	acx565akm_set_sleep_mode(lcd, 1);
 	lcd->enabled = false;
@@ -656,8 +654,7 @@ static void acx565akm_remove(struct spi_device *spi)
 	if (lcd->has_bc)
 		acx565akm_backlight_cleanup(lcd);

-	drm_panel_disable(&lcd->panel);
-	drm_panel_unprepare(&lcd->panel);
+	drm_panel_helper_shutdown(&lcd->panel);
 }

 static const struct of_device_id acx565akm_of_match[] = {
-- 
2.41.0.585.gd2178a4bd4-goog