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auxdisplay: hd44780: Remove clear_fast

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We remove the hd44780_clear_fast (display) clear implementation. With
the new timeout the normal clear_display is reasonably fast. So there is
no need for a clear_fast anymore.

Link: https://lore.kernel.org/lkml/20200922092121.GG16421@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 10:58:23 +01:00 committed by Miguel Ojeda
parent 7b231bb5d0
commit 377cf2cbfd
3 changed files with 8 additions and 87 deletions
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21
drivers/auxdisplay/charlcd.c
View File

@ -125,20 +125,11 @@ static void charlcd_print(struct charlcd *lcd, char c)
lcd->ops->gotoxy(lcd);
}
static void charlcd_clear_fast(struct charlcd *lcd)
static void charlcd_clear_display(struct charlcd *lcd)
{
struct hd44780_common *hdc = lcd->drvdata;
int pos;
charlcd_home(lcd);
if (lcd->ops->clear_fast)
lcd->ops->clear_fast(lcd);
else
for (pos = 0; pos < min(2, lcd->height) * hdc->hwidth; pos++)
lcd->ops->print(lcd, ' ');
charlcd_home(lcd);
lcd->ops->clear_display(lcd);
lcd->addr.x = 0;
lcd->addr.y = 0;
}
/*
@ -409,7 +400,7 @@ static void charlcd_write_char(struct charlcd *lcd, char c)
break;
case '\f':
/* quickly clear the display */
charlcd_clear_fast(lcd);
charlcd_clear_display(lcd);
break;
case '\n':
/*
@ -448,7 +439,7 @@ static void charlcd_write_char(struct charlcd *lcd, char c)
if (!strcmp(priv->esc_seq.buf, "[2J")) {
/* clear the display */
charlcd_clear_fast(lcd);
charlcd_clear_display(lcd);
processed = 1;
} else if (!strcmp(priv->esc_seq.buf, "[H")) {
/* cursor to home */

7
drivers/auxdisplay/charlcd.h
View File

@ -55,8 +55,6 @@ struct charlcd {
/**
* struct charlcd_ops - Functions used by charlcd. Drivers have to implement
* these.
* @clear_fast: Clear the whole display and set cursor to position 0, 0.
* Optional.
* @backlight: Turn backlight on or off. Optional.
* @print: Print one character to the display at current cursor position.
* The buffered cursor position is advanced by charlcd. The cursor should not
@ -65,8 +63,8 @@ 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
* @clear_display: Clear the whole display and set the cursor to 0, 0. The
* values in addr.x and addr.y are set to 0, 0 by charlcd after to calling this
* function.
* @init_display: Initialize the display.
* @shift_cursor: Shift cursor left or right one position.
@ -78,7 +76,6 @@ struct charlcd {
* @redefine_char: Redefine the actual pixel matrix of character.
*/
struct charlcd_ops {
void (*clear_fast)(struct charlcd *lcd);
void (*backlight)(struct charlcd *lcd, enum charlcd_onoff on);
int (*print)(struct charlcd *lcd, int c);
int (*gotoxy)(struct charlcd *lcd);

67
drivers/auxdisplay/panel.c
View File

@ -808,72 +808,7 @@ static void lcd_write_data_tilcd(struct hd44780_common *hdc, int data)
spin_unlock_irq(&pprt_lock);
}
/* fills the display with spaces and resets X/Y */
static void lcd_clear_fast_s(struct charlcd *charlcd)
{
struct hd44780_common *hdc = charlcd->drvdata;
int pos;
spin_lock_irq(&pprt_lock);
for (pos = 0; pos < charlcd->height * hdc->hwidth; pos++) {
lcd_send_serial(0x5F); /* R/W=W, RS=1 */
lcd_send_serial(' ' & 0x0F);
lcd_send_serial((' ' >> 4) & 0x0F);
/* the shortest data takes at least 40 us */
udelay(40);
}
spin_unlock_irq(&pprt_lock);
}
/* fills the display with spaces and resets X/Y */
static void lcd_clear_fast_p8(struct charlcd *charlcd)
{
struct hd44780_common *hdc = charlcd->drvdata;
int pos;
spin_lock_irq(&pprt_lock);
for (pos = 0; pos < charlcd->height * hdc->hwidth; pos++) {
/* present the data to the data port */
w_dtr(pprt, ' ');
/* maintain the data during 20 us before the strobe */
udelay(20);
set_bit(LCD_BIT_E, bits);
set_bit(LCD_BIT_RS, bits);
clear_bit(LCD_BIT_RW, bits);
set_ctrl_bits();
/* maintain the strobe during 40 us */
udelay(40);
clear_bit(LCD_BIT_E, bits);
set_ctrl_bits();
/* the shortest data takes at least 45 us */
udelay(45);
}
spin_unlock_irq(&pprt_lock);
}
/* fills the display with spaces and resets X/Y */
static void lcd_clear_fast_tilcd(struct charlcd *charlcd)
{
struct hd44780_common *hdc = charlcd->drvdata;
int pos;
spin_lock_irq(&pprt_lock);
for (pos = 0; pos < charlcd->height * hdc->hwidth; pos++) {
/* present the data to the data port */
w_dtr(pprt, ' ');
udelay(60);
}
spin_unlock_irq(&pprt_lock);
}
static const struct charlcd_ops charlcd_serial_ops = {
.clear_fast = lcd_clear_fast_s,
.backlight = lcd_backlight,
.gotoxy = hd44780_common_gotoxy,
.home = hd44780_common_home,
@ -890,7 +825,6 @@ static const struct charlcd_ops charlcd_serial_ops = {
};
static const struct charlcd_ops charlcd_parallel_ops = {
.clear_fast = lcd_clear_fast_p8,
.backlight = lcd_backlight,
.gotoxy = hd44780_common_gotoxy,
.home = hd44780_common_home,
@ -907,7 +841,6 @@ static const struct charlcd_ops charlcd_parallel_ops = {
};
static const struct charlcd_ops charlcd_tilcd_ops = {
.clear_fast = lcd_clear_fast_tilcd,
.backlight = lcd_backlight,
.gotoxy = hd44780_common_gotoxy,
.home = hd44780_common_home,