From 1d3b2af213902059d9f4b35eb15b53f8062dc3b3 Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Fri, 10 Mar 2017 15:15:19 +0100 Subject: auxdisplay: charlcd: Add support for displays with more than two lines On displays with more than two lines, the additional lines are stored in the buffers used for the first two lines, but beyond the visible parts. Adjust the DDRAM address calculation to cater for this. When clearing the display, avoid writing more spaces than the actual size of the physical buffer. Signed-off-by: Geert Uytterhoeven Signed-off-by: Greg Kroah-Hartman --- drivers/auxdisplay/charlcd.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) (limited to 'drivers') diff --git a/drivers/auxdisplay/charlcd.c b/drivers/auxdisplay/charlcd.c index b3a84e90a268..cfeb049a01ef 100644 --- a/drivers/auxdisplay/charlcd.c +++ b/drivers/auxdisplay/charlcd.c @@ -159,15 +159,19 @@ EXPORT_SYMBOL_GPL(charlcd_poke); static void charlcd_gotoxy(struct charlcd *lcd) { struct charlcd_priv *priv = to_priv(lcd); + unsigned int addr; - lcd->ops->write_cmd(lcd, - LCD_CMD_SET_DDRAM_ADDR | (priv->addr.y ? lcd->hwidth : 0) | - /* - * we force the cursor to stay at the end of the - * line if it wants to go farther - */ - ((priv->addr.x < lcd->bwidth) ? priv->addr.x & (lcd->hwidth - 1) - : lcd->bwidth - 1)); + /* + * we force the cursor to stay at the end of the + * line if it wants to go farther + */ + addr = priv->addr.x < lcd->bwidth ? priv->addr.x & (lcd->hwidth - 1) + : lcd->bwidth - 1; + if (priv->addr.y & 1) + addr += lcd->hwidth; + if (priv->addr.y & 2) + addr += lcd->bwidth; + lcd->ops->write_cmd(lcd, LCD_CMD_SET_DDRAM_ADDR | addr); } static void charlcd_home(struct charlcd *lcd) @@ -203,7 +207,7 @@ static void charlcd_clear_fast(struct charlcd *lcd) if (lcd->ops->clear_fast) lcd->ops->clear_fast(lcd); else - for (pos = 0; pos < lcd->height * lcd->hwidth; pos++) + for (pos = 0; pos < min(2, lcd->height) * lcd->hwidth; pos++) lcd->ops->write_data(lcd, ' '); charlcd_home(lcd); -- cgit v1.2.3-59-g8ed1b