[PATCH v3 1/2] drm/panel: panel-boe-tv101wum-nl6: tune the power sequence to avoid leakage

[Jitao Shi]

"auo,kd101n80-45na" 2st LCD SPEC update, need to modify the timing
between IOVCC and mipi data.
The 2st version of SPEC modifies the timing requirements from IOVCC to
Mipi Data. IOVCC is now required to take precedence over MIPI DATA,
otherwise there is a risk of leakage. It is recommended that the time
for MIPI to enter LP11 be postponed after IOVCC (delay20ms).

Signed-off-by: Jitao Shi <jitao.shi at mediatek.com>
Change-Id: Ic5212e2145a7dbf2efef9e5585904a93e1bc5a28
---
 drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c | 88 +++++++++++++++++++-------
 include/drm/panel_boe_tv101wum_nl6.h           | 28 ++++++++
 2 files changed, 94 insertions(+), 22 deletions(-)
 create mode 100644 include/drm/panel_boe_tv101wum_nl6.h

diff --git a/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c b/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c
index db9d0b86d542..02efee06c430 100644
--- a/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c
+++ b/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c
@@ -49,7 +49,7 @@ struct boe_panel {
 	struct regulator *avee;
 	struct regulator *avdd;
 	struct gpio_desc *enable_gpio;
-
+	int powered_refcnt;
 	bool prepared;
 };
 
@@ -488,19 +488,15 @@ static int boe_panel_enter_sleep_mode(struct boe_panel *boe)
 	return 0;
 }
 
-static int boe_panel_unprepare(struct drm_panel *panel)
+static int boe_panel_power_off(struct drm_panel *panel)
 {
 	struct boe_panel *boe = to_boe_panel(panel);
-	int ret;
 
-	if (!boe->prepared)
-		return 0;
+	if (WARN_ON(boe->powered_refcnt == 0))
+		return -EINVAL;
 
-	ret = boe_panel_enter_sleep_mode(boe);
-	if (ret < 0) {
-		dev_err(panel->dev, "failed to set panel off: %d\n", ret);
-		return ret;
-	}
+	if (--boe->powered_refcnt != 0)
+		return 0;
 
 	msleep(150);
 
@@ -520,17 +516,45 @@ static int boe_panel_unprepare(struct drm_panel *panel)
 		regulator_disable(boe->pp1800);
 	}
 
+	return 0;
+}
+
+int panel_unprepare_power(struct drm_panel *panel)
+{
+	if (of_device_is_compatible(panel->dev->of_node, "auo,kd101n80-45na"))
+		return boe_panel_power_off(panel);
+
+	return 0;
+}
+EXPORT_SYMBOL(panel_unprepare_power);
+
+static int boe_panel_unprepare(struct drm_panel *panel)
+{
+	struct boe_panel *boe = to_boe_panel(panel);
+	int ret;
+
+	if (!boe->prepared)
+		return 0;
+
+	ret = boe_panel_enter_sleep_mode(boe);
+	if (ret < 0) {
+		dev_err(panel->dev, "failed to set panel off: %d\n", ret);
+		return ret;
+	}
+
+	boe_panel_power_off(panel);
+
 	boe->prepared = false;
 
 	return 0;
 }
 
-static int boe_panel_prepare(struct drm_panel *panel)
+static int boe_panel_power_on(struct drm_panel *panel)
 {
 	struct boe_panel *boe = to_boe_panel(panel);
 	int ret;
 
-	if (boe->prepared)
+	if (++boe->powered_refcnt != 1)
 		return 0;
 
 	gpiod_set_value(boe->enable_gpio, 0);
@@ -558,18 +582,8 @@ static int boe_panel_prepare(struct drm_panel *panel)
 	gpiod_set_value(boe->enable_gpio, 1);
 	usleep_range(6000, 10000);
 
-	ret = boe_panel_init_dcs_cmd(boe);
-	if (ret < 0) {
-		dev_err(panel->dev, "failed to init panel: %d\n", ret);
-		goto poweroff;
-	}
-
-	boe->prepared = true;
-
 	return 0;
 
-poweroff:
-	regulator_disable(boe->avee);
 poweroffavdd:
 	regulator_disable(boe->avdd);
 poweroff1v8:
@@ -580,6 +594,36 @@ static int boe_panel_prepare(struct drm_panel *panel)
 	return ret;
 }
 
+int panel_prepare_power(struct drm_panel *panel)
+{
+	if (of_device_is_compatible(panel->dev->of_node, "auo,kd101n80-45na"))
+		return boe_panel_power_on(panel);
+
+	return 0;
+}
+EXPORT_SYMBOL(panel_prepare_power);
+
+static int boe_panel_prepare(struct drm_panel *panel)
+{
+	struct boe_panel *boe = to_boe_panel(panel);
+	int ret;
+
+	boe_panel_power_on(panel);
+
+	if (boe->prepared)
+		return 0;
+
+	ret = boe_panel_init_dcs_cmd(boe);
+	if (ret < 0) {
+		dev_err(panel->dev, "failed to init panel: %d\n", ret);
+		return ret;
+	}
+
+	boe->prepared = true;
+
+	return 0;
+}
+
 static int boe_panel_enable(struct drm_panel *panel)
 {
 	msleep(130);
diff --git a/include/drm/panel_boe_tv101wum_nl6.h b/include/drm/panel_boe_tv101wum_nl6.h
new file mode 100644
index 000000000000..72abe3eb7840
--- /dev/null
+++ b/include/drm/panel_boe_tv101wum_nl6.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2018 MediaTek Inc.
+ * Author: Jitao Shi <jitao.shi at mediatek.com>
+ */
+
+#ifndef __PANEL_BOE_TV101WUM_NL6_H__
+#define __PANEL_BOE_TV101WUM_NL6_H__
+
+#include <linux/types.h>
+#include <drm/drm_panel.h>
+
+#if defined(CONFIG_DRM_PANEL_BOE_TV101WUM_NL6)
+int panel_unprepare_power(struct drm_panel *panel);
+int panel_prepare_power(struct drm_panel *panel);
+#else
+int panel_unprepare_power(struct drm_panel *panel)
+{
+	return 0;
+}
+
+int panel_prepare_power(struct drm_panel *panel)
+{
+	return 0;
+}
+#endif
+#endif /* __PANEL_BOE_TV101WUM_NL6_H__ */
+
-- 
2.12.5