[PATCH v4 14/32] auxdisplay: Move init_display to hd44780_common

From: poeschel
Date: Mon Oct 05 2020 - 09:01:40 EST


From: Lars Poeschel <poeschel@xxxxxxxxxxx>

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

Reviewed-by: Willy Tarreau <w@xxxxxx>
Signed-off-by: Lars Poeschel <poeschel@xxxxxxxxxxx>
---
drivers/auxdisplay/charlcd.c | 95 ++---------------------------
drivers/auxdisplay/charlcd.h | 9 +++
drivers/auxdisplay/hd44780.c | 2 +
drivers/auxdisplay/hd44780_common.c | 88 ++++++++++++++++++++++++++
drivers/auxdisplay/hd44780_common.h | 2 +
drivers/auxdisplay/panel.c | 3 +
6 files changed, 110 insertions(+), 89 deletions(-)

diff --git a/drivers/auxdisplay/charlcd.c b/drivers/auxdisplay/charlcd.c
index 9631f70e8128..94f6b0afab13 100644
--- a/drivers/auxdisplay/charlcd.c
+++ b/drivers/auxdisplay/charlcd.c
@@ -8,7 +8,6 @@

#include <linux/atomic.h>
#include <linux/ctype.h>
-#include <linux/delay.h>
#include <linux/fs.h>
#include <linux/miscdevice.h>
#include <linux/module.h>
@@ -26,17 +25,7 @@
/* Keep the backlight on this many seconds for each flash */
#define LCD_BL_TEMPO_PERIOD 4

-#define LCD_FLAG_B 0x0004 /* Blink on */
-#define LCD_FLAG_C 0x0008 /* Cursor on */
-#define LCD_FLAG_D 0x0010 /* Display on */
-#define LCD_FLAG_F 0x0020 /* Large font mode */
-#define LCD_FLAG_N 0x0040 /* 2-rows mode */
-#define LCD_FLAG_L 0x0080 /* Backlight enabled */
-
/* LCD commands */
-#define LCD_CMD_ENTRY_MODE 0x04 /* Set entry mode */
-#define LCD_CMD_CURSOR_INC 0x02 /* Increment cursor */
-
#define LCD_CMD_DISPLAY_CTRL 0x08 /* Display control */
#define LCD_CMD_DISPLAY_ON 0x04 /* Set display on */
#define LCD_CMD_CURSOR_ON 0x02 /* Set cursor on */
@@ -84,12 +73,6 @@ struct charlcd_priv {
/* Device single-open policy control */
static atomic_t charlcd_available = ATOMIC_INIT(1);

-/* sleeps that many milliseconds with a reschedule */
-static void long_sleep(int ms)
-{
- schedule_timeout_interruptible(msecs_to_jiffies(ms));
-}
-
/* turn the backlight on or off */
void charlcd_backlight(struct charlcd *lcd, enum charlcd_onoff on)
{
@@ -177,76 +160,6 @@ static void charlcd_clear_fast(struct charlcd *lcd)
charlcd_home(lcd);
}

-static int charlcd_init_display(struct charlcd *lcd)
-{
- void (*write_cmd_raw)(struct hd44780_common *hdc, int cmd);
- struct charlcd_priv *priv = charlcd_to_priv(lcd);
- struct hd44780_common *hdc = lcd->drvdata;
- u8 init;
-
- if (hdc->ifwidth != 4 && hdc->ifwidth != 8)
- return -EINVAL;
-
- priv->flags = ((lcd->height > 1) ? LCD_FLAG_N : 0) | LCD_FLAG_D |
- LCD_FLAG_C | LCD_FLAG_B;
-
- long_sleep(20); /* wait 20 ms after power-up for the paranoid */
-
- /*
- * 8-bit mode, 1 line, small fonts; let's do it 3 times, to make sure
- * the LCD is in 8-bit mode afterwards
- */
- init = LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS;
- if (hdc->ifwidth == 4) {
- init >>= 4;
- write_cmd_raw = hdc->write_cmd_raw4;
- } else {
- write_cmd_raw = hdc->write_cmd;
- }
- write_cmd_raw(hdc, init);
- long_sleep(10);
- write_cmd_raw(hdc, init);
- long_sleep(10);
- write_cmd_raw(hdc, init);
- long_sleep(10);
-
- if (hdc->ifwidth == 4) {
- /* Switch to 4-bit mode, 1 line, small fonts */
- hdc->write_cmd_raw4(hdc, LCD_CMD_FUNCTION_SET >> 4);
- long_sleep(10);
- }
-
- /* set font height and lines number */
- hdc->write_cmd(hdc,
- LCD_CMD_FUNCTION_SET |
- ((hdc->ifwidth == 8) ? LCD_CMD_DATA_LEN_8BITS : 0) |
- ((priv->flags & LCD_FLAG_F) ? LCD_CMD_FONT_5X10_DOTS : 0) |
- ((priv->flags & LCD_FLAG_N) ? LCD_CMD_TWO_LINES : 0));
- long_sleep(10);
-
- /* display off, cursor off, blink off */
- hdc->write_cmd(hdc, LCD_CMD_DISPLAY_CTRL);
- long_sleep(10);
-
- hdc->write_cmd(hdc,
- LCD_CMD_DISPLAY_CTRL | /* set display mode */
- ((priv->flags & LCD_FLAG_D) ? LCD_CMD_DISPLAY_ON : 0) |
- ((priv->flags & LCD_FLAG_C) ? LCD_CMD_CURSOR_ON : 0) |
- ((priv->flags & LCD_FLAG_B) ? LCD_CMD_BLINK_ON : 0));
-
- charlcd_backlight(lcd, (priv->flags & LCD_FLAG_L) ? 1 : 0);
-
- long_sleep(10);
-
- /* entry mode set : increment, cursor shifting */
- hdc->write_cmd(hdc, LCD_CMD_ENTRY_MODE | LCD_CMD_CURSOR_INC);
-
- lcd->ops->clear_display(lcd);
- lcd->addr.x = 0;
- lcd->addr.y = 0;
- return 0;
-}
-
/*
* Parses a movement command of the form "(.*);", where the group can be
* any number of subcommands of the form "(x|y)[0-9]+".
@@ -418,7 +331,9 @@ static inline int handle_lcd_special_code(struct charlcd *lcd)
break;
}
case 'I': /* reinitialize display */
- charlcd_init_display(lcd);
+ lcd->ops->init_display(lcd);
+ priv->flags = ((lcd->height > 1) ? LCD_FLAG_N : 0) | LCD_FLAG_D |
+ LCD_FLAG_C | LCD_FLAG_B;
processed = 1;
break;
case 'G': {
@@ -727,6 +642,8 @@ static int charlcd_init(struct charlcd *lcd)
struct charlcd_priv *priv = charlcd_to_priv(lcd);
int ret;

+ priv->flags = ((lcd->height > 1) ? LCD_FLAG_N : 0) | LCD_FLAG_D |
+ LCD_FLAG_C | LCD_FLAG_B;
if (lcd->ops->backlight) {
mutex_init(&priv->bl_tempo_lock);
INIT_DELAYED_WORK(&priv->bl_work, charlcd_bl_off);
@@ -737,7 +654,7 @@ static int charlcd_init(struct charlcd *lcd)
* Since charlcd_init_display() needs to write data, we have to
* enable mark the LCD initialized just before.
*/
- ret = charlcd_init_display(lcd);
+ ret = lcd->ops->init_display(lcd);
if (ret)
return ret;

diff --git a/drivers/auxdisplay/charlcd.h b/drivers/auxdisplay/charlcd.h
index e5b22e72fdc8..6281cf299a6d 100644
--- a/drivers/auxdisplay/charlcd.h
+++ b/drivers/auxdisplay/charlcd.h
@@ -9,6 +9,13 @@
#ifndef _CHARLCD_H
#define _CHARLCD_H

+#define LCD_FLAG_B 0x0004 /* Blink on */
+#define LCD_FLAG_C 0x0008 /* Cursor on */
+#define LCD_FLAG_D 0x0010 /* Display on */
+#define LCD_FLAG_F 0x0020 /* Large font mode */
+#define LCD_FLAG_N 0x0040 /* 2-rows mode */
+#define LCD_FLAG_L 0x0080 /* Backlight enabled */
+
enum charlcd_onoff {
CHARLCD_OFF = 0,
CHARLCD_ON,
@@ -45,6 +52,7 @@ struct charlcd {
* @clear_display: Again clear the whole display, set the cursor to 0, 0. The
* values in addr.x and addr.y are set to 0, 0 by charlcd prior to calling this
* function.
+ * @init_display: Initialize the display.
*/
struct charlcd_ops {
void (*clear_fast)(struct charlcd *lcd);
@@ -53,6 +61,7 @@ struct charlcd_ops {
int (*gotoxy)(struct charlcd *lcd);
int (*home)(struct charlcd *lcd);
int (*clear_display)(struct charlcd *lcd);
+ int (*init_display)(struct charlcd *lcd);
};

void charlcd_backlight(struct charlcd *lcd, enum charlcd_onoff on);
diff --git a/drivers/auxdisplay/hd44780.c b/drivers/auxdisplay/hd44780.c
index 40ea6d25dbe1..5916da09f738 100644
--- a/drivers/auxdisplay/hd44780.c
+++ b/drivers/auxdisplay/hd44780.c
@@ -130,6 +130,7 @@ static const struct charlcd_ops hd44780_ops_gpio8 = {
.gotoxy = hd44780_common_gotoxy,
.home = hd44780_common_home,
.clear_display = hd44780_common_clear_display,
+ .init_display = hd44780_common_init_display,
};

/* Send a command to the LCD panel in 4 bit GPIO mode */
@@ -177,6 +178,7 @@ static const struct charlcd_ops hd44780_ops_gpio4 = {
.gotoxy = hd44780_common_gotoxy,
.home = hd44780_common_home,
.clear_display = hd44780_common_clear_display,
+ .init_display = hd44780_common_init_display,
};

static int hd44780_probe(struct platform_device *pdev)
diff --git a/drivers/auxdisplay/hd44780_common.c b/drivers/auxdisplay/hd44780_common.c
index 6bc2b3bf6139..8e64de2e44f2 100644
--- a/drivers/auxdisplay/hd44780_common.c
+++ b/drivers/auxdisplay/hd44780_common.c
@@ -9,6 +9,19 @@
/* LCD commands */
#define LCD_CMD_DISPLAY_CLEAR 0x01 /* Clear entire display */

+#define LCD_CMD_ENTRY_MODE 0x04 /* Set entry mode */
+#define LCD_CMD_CURSOR_INC 0x02 /* Increment cursor */
+
+#define LCD_CMD_DISPLAY_CTRL 0x08 /* Display control */
+#define LCD_CMD_DISPLAY_ON 0x04 /* Set display on */
+#define LCD_CMD_CURSOR_ON 0x02 /* Set cursor on */
+#define LCD_CMD_BLINK_ON 0x01 /* Set blink on */
+
+#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 */
+#define LCD_CMD_FONT_5X10_DOTS 0x04 /* Set char font to 5x10 dots */
+
#define LCD_CMD_SET_DDRAM_ADDR 0x80 /* Set display data RAM address */

/* sleeps that many milliseconds with a reschedule */
@@ -70,6 +83,81 @@ int hd44780_common_clear_display(struct charlcd *lcd)
}
EXPORT_SYMBOL_GPL(hd44780_common_clear_display);

+int hd44780_common_init_display(struct charlcd *lcd)
+{
+ struct hd44780_common *hdc = lcd->drvdata;
+
+ void (*write_cmd_raw)(struct hd44780_common *hdc, int cmd);
+ u8 init;
+
+ if (hdc->ifwidth != 4 && hdc->ifwidth != 8)
+ return -EINVAL;
+
+ hdc->hd44780_common_flags = ((lcd->height > 1) ? LCD_FLAG_N : 0) |
+ LCD_FLAG_D | LCD_FLAG_C | LCD_FLAG_B;
+
+ long_sleep(20); /* wait 20 ms after power-up for the paranoid */
+
+ /*
+ * 8-bit mode, 1 line, small fonts; let's do it 3 times, to make sure
+ * the LCD is in 8-bit mode afterwards
+ */
+ init = LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS;
+ if (hdc->ifwidth == 4) {
+ init >>= 4;
+ write_cmd_raw = hdc->write_cmd_raw4;
+ } else {
+ write_cmd_raw = hdc->write_cmd;
+ }
+ write_cmd_raw(hdc, init);
+ long_sleep(10);
+ write_cmd_raw(hdc, init);
+ long_sleep(10);
+ write_cmd_raw(hdc, init);
+ long_sleep(10);
+
+ if (hdc->ifwidth == 4) {
+ /* Switch to 4-bit mode, 1 line, small fonts */
+ hdc->write_cmd_raw4(hdc, LCD_CMD_FUNCTION_SET >> 4);
+ long_sleep(10);
+ }
+
+ /* set font height and lines number */
+ hdc->write_cmd(hdc,
+ LCD_CMD_FUNCTION_SET |
+ ((hdc->ifwidth == 8) ? LCD_CMD_DATA_LEN_8BITS : 0) |
+ ((hdc->hd44780_common_flags & LCD_FLAG_F) ?
+ LCD_CMD_FONT_5X10_DOTS : 0) |
+ ((hdc->hd44780_common_flags & LCD_FLAG_N) ?
+ LCD_CMD_TWO_LINES : 0));
+ long_sleep(10);
+
+ /* display off, cursor off, blink off */
+ hdc->write_cmd(hdc, LCD_CMD_DISPLAY_CTRL);
+ long_sleep(10);
+
+ hdc->write_cmd(hdc,
+ LCD_CMD_DISPLAY_CTRL | /* set display mode */
+ ((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));
+
+ charlcd_backlight(lcd,
+ (hdc->hd44780_common_flags & LCD_FLAG_L) ? 1 : 0);
+
+ long_sleep(10);
+
+ /* entry mode set : increment, cursor shifting */
+ hdc->write_cmd(hdc, LCD_CMD_ENTRY_MODE | LCD_CMD_CURSOR_INC);
+
+ hd44780_common_clear_display(lcd);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(hd44780_common_init_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 11ec4baf6997..cefd78d67675 100644
--- a/drivers/auxdisplay/hd44780_common.h
+++ b/drivers/auxdisplay/hd44780_common.h
@@ -7,6 +7,7 @@ struct hd44780_common {
int ifwidth; /* 4-bit or 8-bit (default) */
int bwidth; /* Default set by hd44780_alloc() */
int hwidth; /* Default set by hd44780_alloc() */
+ unsigned long hd44780_common_flags;
void (*write_data)(struct hd44780_common *hdc, int data);
void (*write_cmd)(struct hd44780_common *hdc, int cmd);
/* write_cmd_raw4 is for 4-bit connected displays only */
@@ -18,5 +19,6 @@ int hd44780_common_print(struct charlcd *lcd, int c);
int hd44780_common_gotoxy(struct charlcd *lcd);
int hd44780_common_home(struct charlcd *lcd);
int hd44780_common_clear_display(struct charlcd *lcd);
+int hd44780_common_init_display(struct charlcd *lcd);
struct hd44780_common *hd44780_common_alloc(void);

diff --git a/drivers/auxdisplay/panel.c b/drivers/auxdisplay/panel.c
index 8adf627529f1..583bd22d3abd 100644
--- a/drivers/auxdisplay/panel.c
+++ b/drivers/auxdisplay/panel.c
@@ -878,6 +878,7 @@ static const struct charlcd_ops charlcd_serial_ops = {
.gotoxy = hd44780_common_gotoxy,
.home = hd44780_common_home,
.clear_display = hd44780_common_clear_display,
+ .init_display = hd44780_common_init_display,
};

static const struct charlcd_ops charlcd_parallel_ops = {
@@ -886,6 +887,7 @@ static const struct charlcd_ops charlcd_parallel_ops = {
.gotoxy = hd44780_common_gotoxy,
.home = hd44780_common_home,
.clear_display = hd44780_common_clear_display,
+ .init_display = hd44780_common_init_display,
};

static const struct charlcd_ops charlcd_tilcd_ops = {
@@ -894,6 +896,7 @@ static const struct charlcd_ops charlcd_tilcd_ops = {
.gotoxy = hd44780_common_gotoxy,
.home = hd44780_common_home,
.clear_display = hd44780_common_clear_display,
+ .init_display = hd44780_common_init_display,
};

/* initialize the LCD driver */
--
2.28.0