auxdisplay: Move init_display to hd44780_common

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

Reviewed-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Lars Poeschel <poeschel@lemonage.de>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This commit is contained in:
Lars Poeschel 2020-11-03 10:58:17 +01:00 committed by Miguel Ojeda
parent bd26b181d1
commit 01ec46dfa6
6 changed files with 110 additions and 89 deletions

View File

@ -8,7 +8,6 @@
#include <linux/atomic.h> #include <linux/atomic.h>
#include <linux/ctype.h> #include <linux/ctype.h>
#include <linux/delay.h>
#include <linux/fs.h> #include <linux/fs.h>
#include <linux/miscdevice.h> #include <linux/miscdevice.h>
#include <linux/module.h> #include <linux/module.h>
@ -26,17 +25,7 @@
/* Keep the backlight on this many seconds for each flash */ /* Keep the backlight on this many seconds for each flash */
#define LCD_BL_TEMPO_PERIOD 4 #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 */ /* 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_CTRL 0x08 /* Display control */
#define LCD_CMD_DISPLAY_ON 0x04 /* Set display on */ #define LCD_CMD_DISPLAY_ON 0x04 /* Set display on */
#define LCD_CMD_CURSOR_ON 0x02 /* Set cursor on */ #define LCD_CMD_CURSOR_ON 0x02 /* Set cursor on */
@ -84,12 +73,6 @@ struct charlcd_priv {
/* Device single-open policy control */ /* Device single-open policy control */
static atomic_t charlcd_available = ATOMIC_INIT(1); 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 */ /* turn the backlight on or off */
void charlcd_backlight(struct charlcd *lcd, enum charlcd_onoff on) 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); 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 * Parses a movement command of the form "(.*);", where the group can be
* any number of subcommands of the form "(x|y)[0-9]+". * 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; break;
} }
case 'I': /* reinitialize display */ 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; processed = 1;
break; break;
case 'G': { case 'G': {
@ -727,6 +642,8 @@ static int charlcd_init(struct charlcd *lcd)
struct charlcd_priv *priv = charlcd_to_priv(lcd); struct charlcd_priv *priv = charlcd_to_priv(lcd);
int ret; int ret;
priv->flags = ((lcd->height > 1) ? LCD_FLAG_N : 0) | LCD_FLAG_D |
LCD_FLAG_C | LCD_FLAG_B;
if (lcd->ops->backlight) { if (lcd->ops->backlight) {
mutex_init(&priv->bl_tempo_lock); mutex_init(&priv->bl_tempo_lock);
INIT_DELAYED_WORK(&priv->bl_work, charlcd_bl_off); 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 * Since charlcd_init_display() needs to write data, we have to
* enable mark the LCD initialized just before. * enable mark the LCD initialized just before.
*/ */
ret = charlcd_init_display(lcd); ret = lcd->ops->init_display(lcd);
if (ret) if (ret)
return ret; return ret;

View File

@ -9,6 +9,13 @@
#ifndef _CHARLCD_H #ifndef _CHARLCD_H
#define _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 { enum charlcd_onoff {
CHARLCD_OFF = 0, CHARLCD_OFF = 0,
CHARLCD_ON, CHARLCD_ON,
@ -46,6 +53,7 @@ struct charlcd {
* @clear_display: Again clear the whole display, set the cursor to 0, 0. The * @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 * values in addr.x and addr.y are set to 0, 0 by charlcd prior to calling this
* function. * function.
* @init_display: Initialize the display.
*/ */
struct charlcd_ops { struct charlcd_ops {
void (*clear_fast)(struct charlcd *lcd); void (*clear_fast)(struct charlcd *lcd);
@ -54,6 +62,7 @@ struct charlcd_ops {
int (*gotoxy)(struct charlcd *lcd); int (*gotoxy)(struct charlcd *lcd);
int (*home)(struct charlcd *lcd); int (*home)(struct charlcd *lcd);
int (*clear_display)(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); void charlcd_backlight(struct charlcd *lcd, enum charlcd_onoff on);

View File

@ -130,6 +130,7 @@ static const struct charlcd_ops hd44780_ops_gpio8 = {
.gotoxy = hd44780_common_gotoxy, .gotoxy = hd44780_common_gotoxy,
.home = hd44780_common_home, .home = hd44780_common_home,
.clear_display = hd44780_common_clear_display, .clear_display = hd44780_common_clear_display,
.init_display = hd44780_common_init_display,
}; };
/* Send a command to the LCD panel in 4 bit GPIO mode */ /* 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, .gotoxy = hd44780_common_gotoxy,
.home = hd44780_common_home, .home = hd44780_common_home,
.clear_display = hd44780_common_clear_display, .clear_display = hd44780_common_clear_display,
.init_display = hd44780_common_init_display,
}; };
static int hd44780_probe(struct platform_device *pdev) static int hd44780_probe(struct platform_device *pdev)

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@ -9,6 +9,19 @@
/* LCD commands */ /* LCD commands */
#define LCD_CMD_DISPLAY_CLEAR 0x01 /* Clear entire display */ #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 */ #define LCD_CMD_SET_DDRAM_ADDR 0x80 /* Set display data RAM address */
/* sleeps that many milliseconds with a reschedule */ /* 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); 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 *hd44780_common_alloc(void)
{ {
struct hd44780_common *hd; struct hd44780_common *hd;

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@ -7,6 +7,7 @@ struct hd44780_common {
int ifwidth; /* 4-bit or 8-bit (default) */ int ifwidth; /* 4-bit or 8-bit (default) */
int bwidth; /* Default set by hd44780_alloc() */ int bwidth; /* Default set by hd44780_alloc() */
int hwidth; /* 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_data)(struct hd44780_common *hdc, int data);
void (*write_cmd)(struct hd44780_common *hdc, int cmd); void (*write_cmd)(struct hd44780_common *hdc, int cmd);
/* write_cmd_raw4 is for 4-bit connected displays only */ /* write_cmd_raw4 is for 4-bit connected displays only */
@ -18,4 +19,5 @@ int hd44780_common_print(struct charlcd *lcd, int c);
int hd44780_common_gotoxy(struct charlcd *lcd); int hd44780_common_gotoxy(struct charlcd *lcd);
int hd44780_common_home(struct charlcd *lcd); int hd44780_common_home(struct charlcd *lcd);
int hd44780_common_clear_display(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); struct hd44780_common *hd44780_common_alloc(void);

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@ -878,6 +878,7 @@ static const struct charlcd_ops charlcd_serial_ops = {
.gotoxy = hd44780_common_gotoxy, .gotoxy = hd44780_common_gotoxy,
.home = hd44780_common_home, .home = hd44780_common_home,
.clear_display = hd44780_common_clear_display, .clear_display = hd44780_common_clear_display,
.init_display = hd44780_common_init_display,
}; };
static const struct charlcd_ops charlcd_parallel_ops = { static const struct charlcd_ops charlcd_parallel_ops = {
@ -886,6 +887,7 @@ static const struct charlcd_ops charlcd_parallel_ops = {
.gotoxy = hd44780_common_gotoxy, .gotoxy = hd44780_common_gotoxy,
.home = hd44780_common_home, .home = hd44780_common_home,
.clear_display = hd44780_common_clear_display, .clear_display = hd44780_common_clear_display,
.init_display = hd44780_common_init_display,
}; };
static const struct charlcd_ops charlcd_tilcd_ops = { static const struct charlcd_ops charlcd_tilcd_ops = {
@ -894,6 +896,7 @@ static const struct charlcd_ops charlcd_tilcd_ops = {
.gotoxy = hd44780_common_gotoxy, .gotoxy = hd44780_common_gotoxy,
.home = hd44780_common_home, .home = hd44780_common_home,
.clear_display = hd44780_common_clear_display, .clear_display = hd44780_common_clear_display,
.init_display = hd44780_common_init_display,
}; };
/* initialize the LCD driver */ /* initialize the LCD driver */