Commit 45421ffe authored by Lars Poeschel's avatar Lars Poeschel Committed by Miguel Ojeda
Browse files

auxdisplay: Move clear_display to hd44780_common 



This moves the clear_display function from charlcd to hd44780_common.
This is one more step to make charlcd independent from device specific
code. The two hd44780 drivers use the new function from hd44780_common
and charlcd calls this function through its function pointer in its ops
structure.

Reviewed-by: default avatarWilly Tarreau <w@1wt.eu>
Signed-off-by: default avatarLars Poeschel <poeschel@lemonage.de>
Signed-off-by: default avatarMiguel Ojeda <ojeda@kernel.org>
parent 88645a86

drivers/auxdisplay/charlcd.c

+6 −16
Original line number Diff line number Diff line
@@ -34,8 +34,6 @@ 
#define LCD_FLAG_L		0x0080	/* Backlight enabled */



/* 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 */
@@ -178,18 +176,6 @@ static void charlcd_clear_fast(struct charlcd *lcd) 
	charlcd_home(lcd);

}



/* clears the display and resets X/Y */

static void charlcd_clear_display(struct charlcd *lcd)

{

	struct hd44780_common *hdc = lcd->drvdata;



	hdc->write_cmd(hdc, LCD_CMD_DISPLAY_CLEAR);

	lcd->addr.x = 0;

	lcd->addr.y = 0;

	/* we must wait a few milliseconds (15) */

	long_sleep(15);

}



static int charlcd_init_display(struct charlcd *lcd)

{

	void (*write_cmd_raw)(struct hd44780_common *hdc, int cmd);
@@ -254,7 +240,9 @@ static int charlcd_init_display(struct charlcd *lcd) 
	/* entry mode set : increment, cursor shifting */

	hdc->write_cmd(hdc, LCD_CMD_ENTRY_MODE | LCD_CMD_CURSOR_INC);



	charlcd_clear_display(lcd);

	lcd->ops->clear_display(lcd);

	lcd->addr.x = 0;

	lcd->addr.y = 0;

	return 0;

}
@@ -670,8 +658,10 @@ static int charlcd_open(struct inode *inode, struct file *file) 
		goto fail;



	if (priv->must_clear) {

		charlcd_clear_display(&priv->lcd);

		priv->lcd.ops->clear_display(&priv->lcd);

		priv->must_clear = false;

		priv->lcd.addr.x = 0;

		priv->lcd.addr.y = 0;

	}

	return nonseekable_open(inode, file);

drivers/auxdisplay/charlcd.h

+4 −0
Original line number Diff line number Diff line
@@ -43,6 +43,9 @@ struct charlcd { 
 * previously set in addr.x and addr.y by charlcd.

 * @home: Set cursor to 0, 0. The values in addr.x and addr.y are set to 0, 0 by

 * charlcd prior to calling this function.

 * @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.

 */

struct charlcd_ops {

	void (*clear_fast)(struct charlcd *lcd);
@@ -50,6 +53,7 @@ struct charlcd_ops { 
	int (*print)(struct charlcd *lcd, int c);

	int (*gotoxy)(struct charlcd *lcd);

	int (*home)(struct charlcd *lcd);

	int (*clear_display)(struct charlcd *lcd);

};



struct charlcd *charlcd_alloc(void);

drivers/auxdisplay/hd44780.c

+2 −0
Original line number Diff line number Diff line
@@ -129,6 +129,7 @@ static const struct charlcd_ops hd44780_ops_gpio8 = { 
	.print		= hd44780_common_print,

	.gotoxy		= hd44780_common_gotoxy,

	.home		= hd44780_common_home,

	.clear_display	= hd44780_common_clear_display,

};



/* Send a command to the LCD panel in 4 bit GPIO mode */
@@ -175,6 +176,7 @@ static const struct charlcd_ops hd44780_ops_gpio4 = { 
	.print		= hd44780_common_print,

	.gotoxy		= hd44780_common_gotoxy,

	.home		= hd44780_common_home,

	.clear_display	= hd44780_common_clear_display,

};



static int hd44780_probe(struct platform_device *pdev)

drivers/auxdisplay/hd44780_common.c

+21 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-or-later

#include <linux/module.h>

#include <linux/sched.h>

#include <linux/slab.h>



#include "charlcd.h"

#include "hd44780_common.h"



/* LCD commands */

#define LCD_CMD_DISPLAY_CLEAR	0x01	/* Clear entire display */



#define LCD_CMD_SET_DDRAM_ADDR	0x80	/* Set display data RAM address */



/* sleeps that many milliseconds with a reschedule */

static void long_sleep(int ms)

{

	schedule_timeout_interruptible(msecs_to_jiffies(ms));

}



int hd44780_common_print(struct charlcd *lcd, int c)

{

	struct hd44780_common *hdc = lcd->drvdata;
@@ -49,6 +58,18 @@ int hd44780_common_home(struct charlcd *lcd) 
}

EXPORT_SYMBOL_GPL(hd44780_common_home);



/* clears the display and resets X/Y */

int hd44780_common_clear_display(struct charlcd *lcd)

{

	struct hd44780_common *hdc = lcd->drvdata;



	hdc->write_cmd(hdc, LCD_CMD_DISPLAY_CLEAR);

	/* we must wait a few milliseconds (15) */

	long_sleep(15);

	return 0;

}

EXPORT_SYMBOL_GPL(hd44780_common_clear_display);



struct hd44780_common *hd44780_common_alloc(void)

{

	struct hd44780_common *hd;

drivers/auxdisplay/hd44780_common.h

+1 −0
Original line number Diff line number Diff line
@@ -17,4 +17,5 @@ struct hd44780_common { 
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);

struct hd44780_common *hd44780_common_alloc(void);