[PATCH v4 17/32] auxdisplay: Implement a hd44780_common_display

[poeschel]

From: Lars Poeschel <poeschel@xxxxxxxxxxx>

Implement a hd44780_common_display function to turn the whole display on
or off. The hd44780 drivers can use this and charlcd uses this through
its ops function pointer.

Reviewed-by: Willy Tarreau <w@xxxxxx>
Signed-off-by: Lars Poeschel <poeschel@xxxxxxxxxxx>
---
 drivers/auxdisplay/charlcd.c        |  6 ++++++
 drivers/auxdisplay/charlcd.h        |  2 ++
 drivers/auxdisplay/hd44780.c        |  2 ++
 drivers/auxdisplay/hd44780_common.c | 26 ++++++++++++++++++++++++++
 drivers/auxdisplay/hd44780_common.h |  1 +
 drivers/auxdisplay/panel.c          |  3 +++
 6 files changed, 40 insertions(+)

diff --git a/drivers/auxdisplay/charlcd.c b/drivers/auxdisplay/charlcd.c
index e48287197732..9bd3c0f2c470 100644
--- a/drivers/auxdisplay/charlcd.c
+++ b/drivers/auxdisplay/charlcd.c
@@ -232,10 +232,16 @@ static inline int handle_lcd_special_code(struct charlcd *lcd)
 	switch (*esc) {
 	case 'D':	/* Display ON */
 		priv->flags |= LCD_FLAG_D;
+		if (priv->flags != oldflags)
+			lcd->ops->display(lcd, CHARLCD_ON);
+
 		processed = 1;
 		break;
 	case 'd':	/* Display OFF */
 		priv->flags &= ~LCD_FLAG_D;
+		if (priv->flags != oldflags)
+			lcd->ops->display(lcd, CHARLCD_OFF);
+
 		processed = 1;
 		break;
 	case 'C':	/* Cursor ON */
diff --git a/drivers/auxdisplay/charlcd.h b/drivers/auxdisplay/charlcd.h
index 6fd4a77f5794..ec739a25195e 100644
--- a/drivers/auxdisplay/charlcd.h
+++ b/drivers/auxdisplay/charlcd.h
@@ -60,6 +60,7 @@ struct charlcd {
  * @init_display: Initialize the display.
  * @shift_cursor: Shift cursor left or right one position.
  * @shift_display: Shift whole display content left or right.
+ * @display: Turn display on or off.
  */
 struct charlcd_ops {
 	void (*clear_fast)(struct charlcd *lcd);
@@ -71,6 +72,7 @@ struct charlcd_ops {
 	int (*init_display)(struct charlcd *lcd);
 	int (*shift_cursor)(struct charlcd *lcd, enum charlcd_shift_dir dir);
 	int (*shift_display)(struct charlcd *lcd, enum charlcd_shift_dir dir);
+	int (*display)(struct charlcd *lcd, enum charlcd_onoff on);
 };
 
 void charlcd_backlight(struct charlcd *lcd, enum charlcd_onoff on);
diff --git a/drivers/auxdisplay/hd44780.c b/drivers/auxdisplay/hd44780.c
index a3b18bbc2e4a..0f76b812fa20 100644
--- a/drivers/auxdisplay/hd44780.c
+++ b/drivers/auxdisplay/hd44780.c
@@ -133,6 +133,7 @@ static const struct charlcd_ops hd44780_ops_gpio8 = {
 	.init_display	= hd44780_common_init_display,
 	.shift_cursor	= hd44780_common_shift_cursor,
 	.shift_display	= hd44780_common_shift_display,
+	.display	= hd44780_common_display,
 };
 
 /* Send a command to the LCD panel in 4 bit GPIO mode */
@@ -183,6 +184,7 @@ static const struct charlcd_ops hd44780_ops_gpio4 = {
 	.init_display	= hd44780_common_init_display,
 	.shift_cursor	= hd44780_common_shift_cursor,
 	.shift_display	= hd44780_common_shift_display,
+	.display	= hd44780_common_display,
 };
 
 static int hd44780_probe(struct platform_device *pdev)
diff --git a/drivers/auxdisplay/hd44780_common.c b/drivers/auxdisplay/hd44780_common.c
index 972c74a22294..07fd03555e99 100644
--- a/drivers/auxdisplay/hd44780_common.c
+++ b/drivers/auxdisplay/hd44780_common.c
@@ -196,6 +196,32 @@ int hd44780_common_shift_display(struct charlcd *lcd,
 }
 EXPORT_SYMBOL_GPL(hd44780_common_shift_display);
 
+static void hd44780_common_set_mode(struct hd44780_common *hdc)
+{
+	hdc->write_cmd(hdc,
+		LCD_CMD_DISPLAY_CTRL |
+		((hdc->hd44780_common_flags & LCD_FLAG_D) ?
+			LCD_CMD_DISPLAY_ON : 0) |
+		((hdc->hd44780_common_flags & LCD_FLAG_C) ?
+			LCD_CMD_CURSOR_ON : 0) |
+		((hdc->hd44780_common_flags & LCD_FLAG_B) ?
+			LCD_CMD_BLINK_ON : 0));
+}
+
+int hd44780_common_display(struct charlcd *lcd, enum charlcd_onoff on)
+{
+	struct hd44780_common *hdc = lcd->drvdata;
+
+	if (on == CHARLCD_ON)
+		hdc->hd44780_common_flags |= LCD_FLAG_D;
+	else
+		hdc->hd44780_common_flags &= ~LCD_FLAG_D;
+
+	hd44780_common_set_mode(hdc);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_display);
+
 struct hd44780_common *hd44780_common_alloc(void)
 {
 	struct hd44780_common *hd;
diff --git a/drivers/auxdisplay/hd44780_common.h b/drivers/auxdisplay/hd44780_common.h
index 7badb96cb8a9..1550fa77b956 100644
--- a/drivers/auxdisplay/hd44780_common.h
+++ b/drivers/auxdisplay/hd44780_common.h
@@ -24,5 +24,6 @@ int hd44780_common_shift_cursor(struct charlcd *lcd,
 		enum charlcd_shift_dir dir);
 int hd44780_common_shift_display(struct charlcd *lcd,
 		enum charlcd_shift_dir dir);
+int hd44780_common_display(struct charlcd *lcd, enum charlcd_onoff on);
 struct hd44780_common *hd44780_common_alloc(void);
 
diff --git a/drivers/auxdisplay/panel.c b/drivers/auxdisplay/panel.c
index 7ebbfb338518..9cb895c74cfb 100644
--- a/drivers/auxdisplay/panel.c
+++ b/drivers/auxdisplay/panel.c
@@ -881,6 +881,7 @@ static const struct charlcd_ops charlcd_serial_ops = {
 	.init_display	= hd44780_common_init_display,
 	.shift_cursor	= hd44780_common_shift_cursor,
 	.shift_display	= hd44780_common_shift_display,
+	.display	= hd44780_common_display,
 };
 
 static const struct charlcd_ops charlcd_parallel_ops = {
@@ -892,6 +893,7 @@ static const struct charlcd_ops charlcd_parallel_ops = {
 	.init_display	= hd44780_common_init_display,
 	.shift_cursor	= hd44780_common_shift_cursor,
 	.shift_display	= hd44780_common_shift_display,
+	.display	= hd44780_common_display,
 };
 
 static const struct charlcd_ops charlcd_tilcd_ops = {
@@ -903,6 +905,7 @@ static const struct charlcd_ops charlcd_tilcd_ops = {
 	.init_display	= hd44780_common_init_display,
 	.shift_cursor	= hd44780_common_shift_cursor,
 	.shift_display	= hd44780_common_shift_display,
+	.display	= hd44780_common_display,
 };
 
 /* initialize the LCD driver */
-- 
2.28.0