[PATCH v3 16/32] auxdisplay: Implement hd44780_common_display_shift

From: poeschel
Date: Mon Oct 05 2020 - 08:14:11 EST


From: Lars Poeschel <poeschel@xxxxxxxxxxx>

Implement a hd44780_common_display_shift function for hd44780 drivers to
use. 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 | 10 ++--------
drivers/auxdisplay/charlcd.h | 2 ++
drivers/auxdisplay/hd44780.c | 2 ++
drivers/auxdisplay/hd44780_common.c | 16 ++++++++++++++++
drivers/auxdisplay/hd44780_common.h | 2 ++
drivers/auxdisplay/panel.c | 3 +++
6 files changed, 27 insertions(+), 8 deletions(-)

diff --git a/drivers/auxdisplay/charlcd.c b/drivers/auxdisplay/charlcd.c
index 85747e13bf48..e48287197732 100644
--- a/drivers/auxdisplay/charlcd.c
+++ b/drivers/auxdisplay/charlcd.c
@@ -31,10 +31,6 @@
#define LCD_CMD_CURSOR_ON 0x02 /* Set cursor on */
#define LCD_CMD_BLINK_ON 0x01 /* Set blink on */

-#define LCD_CMD_SHIFT 0x10 /* Shift cursor/display */
-#define LCD_CMD_DISPLAY_SHIFT 0x08 /* Shift display instead of cursor */
-#define LCD_CMD_SHIFT_RIGHT 0x04 /* Shift display/cursor to the right */
-
#define LCD_CMD_FUNCTION_SET 0x20 /* Set function */
#define LCD_CMD_DATA_LEN_8BITS 0x10 /* Set data length to 8 bits */
#define LCD_CMD_TWO_LINES 0x08 /* Set to two display lines */
@@ -303,13 +299,11 @@ static inline int handle_lcd_special_code(struct charlcd *lcd)
processed = 1;
break;
case 'L': /* shift display left */
- hdc->write_cmd(hdc, LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT);
+ lcd->ops->shift_display(lcd, CHARLCD_SHIFT_LEFT);
processed = 1;
break;
case 'R': /* shift display right */
- hdc->write_cmd(hdc,
- LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT |
- LCD_CMD_SHIFT_RIGHT);
+ lcd->ops->shift_display(lcd, CHARLCD_SHIFT_RIGHT);
processed = 1;
break;
case 'k': { /* kill end of line */
diff --git a/drivers/auxdisplay/charlcd.h b/drivers/auxdisplay/charlcd.h
index 0a340beacd3e..6fd4a77f5794 100644
--- a/drivers/auxdisplay/charlcd.h
+++ b/drivers/auxdisplay/charlcd.h
@@ -59,6 +59,7 @@ struct charlcd {
* function.
* @init_display: Initialize the display.
* @shift_cursor: Shift cursor left or right one position.
+ * @shift_display: Shift whole display content left or right.
*/
struct charlcd_ops {
void (*clear_fast)(struct charlcd *lcd);
@@ -69,6 +70,7 @@ struct charlcd_ops {
int (*clear_display)(struct charlcd *lcd);
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);
};

void charlcd_backlight(struct charlcd *lcd, enum charlcd_onoff on);
diff --git a/drivers/auxdisplay/hd44780.c b/drivers/auxdisplay/hd44780.c
index 6ffeeb3fb0d0..a3b18bbc2e4a 100644
--- a/drivers/auxdisplay/hd44780.c
+++ b/drivers/auxdisplay/hd44780.c
@@ -132,6 +132,7 @@ static const struct charlcd_ops hd44780_ops_gpio8 = {
.clear_display = hd44780_common_clear_display,
.init_display = hd44780_common_init_display,
.shift_cursor = hd44780_common_shift_cursor,
+ .shift_display = hd44780_common_shift_display,
};

/* Send a command to the LCD panel in 4 bit GPIO mode */
@@ -181,6 +182,7 @@ static const struct charlcd_ops hd44780_ops_gpio4 = {
.clear_display = hd44780_common_clear_display,
.init_display = hd44780_common_init_display,
.shift_cursor = hd44780_common_shift_cursor,
+ .shift_display = hd44780_common_shift_display,
};

static int hd44780_probe(struct platform_device *pdev)
diff --git a/drivers/auxdisplay/hd44780_common.c b/drivers/auxdisplay/hd44780_common.c
index 894a195eda39..972c74a22294 100644
--- a/drivers/auxdisplay/hd44780_common.c
+++ b/drivers/auxdisplay/hd44780_common.c
@@ -18,6 +18,7 @@
#define LCD_CMD_BLINK_ON 0x01 /* Set blink on */

#define LCD_CMD_SHIFT 0x10 /* Shift cursor/display */
+#define LCD_CMD_DISPLAY_SHIFT 0x08 /* Shift display instead of cursor */
#define LCD_CMD_SHIFT_RIGHT 0x04 /* Shift display/cursor to the right */

#define LCD_CMD_FUNCTION_SET 0x20 /* Set function */
@@ -180,6 +181,21 @@ int hd44780_common_shift_cursor(struct charlcd *lcd, enum charlcd_shift_dir dir)
}
EXPORT_SYMBOL_GPL(hd44780_common_shift_cursor);

+int hd44780_common_shift_display(struct charlcd *lcd,
+ enum charlcd_shift_dir dir)
+{
+ struct hd44780_common *hdc = lcd->drvdata;
+
+ if (dir == CHARLCD_SHIFT_LEFT)
+ hdc->write_cmd(hdc, LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT);
+ else if (dir == CHARLCD_SHIFT_RIGHT)
+ hdc->write_cmd(hdc, LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT |
+ LCD_CMD_SHIFT_RIGHT);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_shift_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 432fc37213cf..7badb96cb8a9 100644
--- a/drivers/auxdisplay/hd44780_common.h
+++ b/drivers/auxdisplay/hd44780_common.h
@@ -22,5 +22,7 @@ int hd44780_common_clear_display(struct charlcd *lcd);
int hd44780_common_init_display(struct charlcd *lcd);
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);
struct hd44780_common *hd44780_common_alloc(void);

diff --git a/drivers/auxdisplay/panel.c b/drivers/auxdisplay/panel.c
index 4275223080e8..7ebbfb338518 100644
--- a/drivers/auxdisplay/panel.c
+++ b/drivers/auxdisplay/panel.c
@@ -880,6 +880,7 @@ static const struct charlcd_ops charlcd_serial_ops = {
.clear_display = hd44780_common_clear_display,
.init_display = hd44780_common_init_display,
.shift_cursor = hd44780_common_shift_cursor,
+ .shift_display = hd44780_common_shift_display,
};

static const struct charlcd_ops charlcd_parallel_ops = {
@@ -890,6 +891,7 @@ static const struct charlcd_ops charlcd_parallel_ops = {
.clear_display = hd44780_common_clear_display,
.init_display = hd44780_common_init_display,
.shift_cursor = hd44780_common_shift_cursor,
+ .shift_display = hd44780_common_shift_display,
};

static const struct charlcd_ops charlcd_tilcd_ops = {
@@ -900,6 +902,7 @@ static const struct charlcd_ops charlcd_tilcd_ops = {
.clear_display = hd44780_common_clear_display,
.init_display = hd44780_common_init_display,
.shift_cursor = hd44780_common_shift_cursor,
+ .shift_display = hd44780_common_shift_display,
};

/* initialize the LCD driver */
--
2.28.0