[PATCH V5 REPOST 3/7] lcd: calculate line_length after lcd_ctrl_init()

Stephen Warren swarren at wwwdotorg.org
Tue Jan 15 21:26:55 EST 2013

When an LCD driver is actually driving a regular external display, e.g.
an HDMI monitor, the display resolution might not be known until the
display controller has initialized, i.e. during lcd_ctrl_init(). However,
lcd.c calculates lcd_line_length before calling this function, thus
relying on a hard-coded resolution in struct panel_info.

Instead, defer this calculation until after lcd_ctrl_init() has had the
chance to dynamically determine the resolution. This needs to happen
before lcd_clear(), since the value is used there.

grep indicates that no code outside lcd.c uses this lcd_line_length; in
particular, no lcd_ctrl_init() implementations read it.

Signed-off-by: Stephen Warren <swarren at wwwdotorg.org>
Acked-by: Anatolij Gustschin <agust at denx.de>
v5: No change; merged patch series.
v4: Adjusted to addition of lcd_get_size() function. Rebased.
v3: No change.
 common/lcd.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/common/lcd.c b/common/lcd.c
index 66d4f94..9fa4e5c 100644
--- a/common/lcd.c
+++ b/common/lcd.c
@@ -384,8 +384,6 @@ int drv_lcd_init (void)
 	lcd_base = (void *)(gd->fb_base);
-	lcd_get_size(&lcd_line_length);
 	lcd_init(lcd_base);		/* LCD initialization */
 	/* Device initialization */
@@ -468,6 +466,8 @@ static int lcd_init(void *lcdbase)
 	debug("[LCD] Initializing LCD frambuffer at %p\n", lcdbase);
+	lcd_get_size(&lcd_line_length);
+	lcd_line_length = (panel_info.vl_col * NBITS(panel_info.vl_bpix)) / 8;
 	lcd_is_enabled = 1;
 	lcd_enable ();

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