diff options
| -rw-r--r-- | drivers/auxdisplay/charlcd.c | 36 | ||||
| -rw-r--r-- | include/misc/charlcd.h | 2 |
2 files changed, 32 insertions, 6 deletions
diff --git a/drivers/auxdisplay/charlcd.c b/drivers/auxdisplay/charlcd.c index 930ffb2fb317..b3a84e90a268 100644 --- a/drivers/auxdisplay/charlcd.c +++ b/drivers/auxdisplay/charlcd.c @@ -223,24 +223,46 @@ static void charlcd_clear_display(struct charlcd *lcd) static int charlcd_init_display(struct charlcd *lcd) { + void (*write_cmd_raw)(struct charlcd *lcd, int cmd); struct charlcd_priv *priv = to_priv(lcd); + u8 init; + + if (lcd->ifwidth != 4 && lcd->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 */ - /* 8bits, 1 line, small fonts; let's do it 3 times */ - lcd->ops->write_cmd(lcd, LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS); + /* + * 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 (lcd->ifwidth == 4) { + init >>= 4; + write_cmd_raw = lcd->ops->write_cmd_raw4; + } else { + write_cmd_raw = lcd->ops->write_cmd; + } + write_cmd_raw(lcd, init); long_sleep(10); - lcd->ops->write_cmd(lcd, LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS); + write_cmd_raw(lcd, init); long_sleep(10); - lcd->ops->write_cmd(lcd, LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS); + write_cmd_raw(lcd, init); long_sleep(10); + if (lcd->ifwidth == 4) { + /* Switch to 4-bit mode, 1 line, small fonts */ + lcd->ops->write_cmd_raw4(lcd, LCD_CMD_FUNCTION_SET >> 4); + long_sleep(10); + } + /* set font height and lines number */ lcd->ops->write_cmd(lcd, - LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS | + LCD_CMD_FUNCTION_SET | + ((lcd->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); @@ -482,7 +504,8 @@ static inline int handle_lcd_special_code(struct charlcd *lcd) /* check whether one of F,N flags was changed */ else if ((oldflags ^ priv->flags) & (LCD_FLAG_F | LCD_FLAG_N)) lcd->ops->write_cmd(lcd, - LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS | + LCD_CMD_FUNCTION_SET | + ((lcd->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)); /* check whether L flag was changed */ @@ -716,6 +739,7 @@ struct charlcd *charlcd_alloc(unsigned int drvdata_size) priv->esc_seq.len = -1; lcd = &priv->lcd; + lcd->ifwidth = 8; lcd->bwidth = DEFAULT_LCD_BWIDTH; lcd->hwidth = DEFAULT_LCD_HWIDTH; lcd->drvdata = priv->drvdata; diff --git a/include/misc/charlcd.h b/include/misc/charlcd.h index c40047b673c9..23f61850f363 100644 --- a/include/misc/charlcd.h +++ b/include/misc/charlcd.h @@ -14,6 +14,7 @@ struct charlcd { const struct charlcd_ops *ops; const unsigned char *char_conv; /* Optional */ + int ifwidth; /* 4-bit or 8-bit (default) */ int height; int width; int bwidth; /* Default set by charlcd_alloc() */ @@ -28,6 +29,7 @@ struct charlcd_ops { void (*write_data)(struct charlcd *lcd, int data); /* Optional */ + void (*write_cmd_raw4)(struct charlcd *lcd, int cmd); /* 4-bit only */ void (*clear_fast)(struct charlcd *lcd); void (*backlight)(struct charlcd *lcd, int on); }; |