| From 6bb3f4d8de6da233738c058f3fb0016fffd5d81b Mon Sep 17 00:00:00 2001 |
| From: Laurent Pinchart <laurent.pinchart@ideasonboard.com> |
| Date: Wed, 13 Jul 2011 12:13:47 +0200 |
| Subject: fbdev: sh_mobile_lcdc: Compute clock pattern using divider |
| denominator |
| |
| The clock divider pattern is computed based on the dot clock register |
| value which stores the divider denumerator. However, when using a 1:1 |
| divider ratio, the register is programmed with a value that must not be |
| interpreted as a denominator. This results in a shift left operation |
| with a value of 32, which produces undefined behaviour. |
| |
| Compute the clock pattern using the divider denominator, not the dot |
| clock register value. |
| |
| Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> |
| (cherry picked from commit 505c7de51fe5ebb81fac096cb8cebd7cb45b7955) |
| |
| Signed-off-by: Simon Horman <horms@verge.net.au> |
| --- |
| drivers/video/sh_mobile_lcdcfb.c | 10 ++++++---- |
| 1 file changed, 6 insertions(+), 4 deletions(-) |
| |
| diff --git a/drivers/video/sh_mobile_lcdcfb.c b/drivers/video/sh_mobile_lcdcfb.c |
| index 99656f5..2d935db 100644 |
| --- a/drivers/video/sh_mobile_lcdcfb.c |
| +++ b/drivers/video/sh_mobile_lcdcfb.c |
| @@ -481,13 +481,15 @@ static int sh_mobile_lcdc_start(struct sh_mobile_lcdc_priv *priv) |
| if (!m) |
| continue; |
| |
| + /* FIXME: sh7724 can only use 42, 48, 54 and 60 for the divider |
| + * denominator. |
| + */ |
| + lcdc_write_chan(ch, LDDCKPAT1R, 0); |
| + lcdc_write_chan(ch, LDDCKPAT2R, (1 << (m/2)) - 1); |
| + |
| if (m == 1) |
| m = LDDCKR_MOSEL; |
| tmp |= m << (lcdc_chan_is_sublcd(ch) ? 8 : 0); |
| - |
| - /* FIXME: sh7724 can only use 42, 48, 54 and 60 for the divider denominator */ |
| - lcdc_write_chan(ch, LDDCKPAT1R, 0); |
| - lcdc_write_chan(ch, LDDCKPAT2R, (1 << (m/2)) - 1); |
| } |
| |
| lcdc_write(priv, _LDDCKR, tmp); |
| -- |
| 1.7.10 |
| |