[PATCH 2/4] [resend #2] tridentfb: Fix set_lwidth on TGUI9440 and CYBER9320
From: Ondrej Zary <hidden>
Date: 2015-08-24 19:37:58
Also in:
lkml
Subsystem:
framebuffer layer, the rest · Maintainers:
Helge Deller, Linus Torvalds
According to X.Org driver, chips older than TGUI9660 have only 1 width bit in AddColReg. Touching the 2nd one causes I2C/DDC to fail on TGUI9440. Set only 1 bit of width in AddColReg on TGUI9440 and CYBER9320. Signed-off-by: Ondrej Zary <redacted> --- drivers/video/fbdev/tridentfb.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/video/fbdev/tridentfb.c b/drivers/video/fbdev/tridentfb.c
index 7429713..01b43e9 100644
--- a/drivers/video/fbdev/tridentfb.c
+++ b/drivers/video/fbdev/tridentfb.c@@ -673,8 +673,14 @@ static int get_nativex(struct tridentfb_par *par) static inline void set_lwidth(struct tridentfb_par *par, int width) { write3X4(par, VGA_CRTC_OFFSET, width & 0xFF); - write3X4(par, AddColReg, - (read3X4(par, AddColReg) & 0xCF) | ((width & 0x300) >> 4)); + /* chips older than TGUI9660 have only 1 width bit in AddColReg */ + /* touching the other one breaks I2C/DDC */ + if (par->chip_id = TGUI9440 || par->chip_id = CYBER9320) + write3X4(par, AddColReg, + (read3X4(par, AddColReg) & 0xEF) | ((width & 0x100) >> 4)); + else + write3X4(par, AddColReg, + (read3X4(par, AddColReg) & 0xCF) | ((width & 0x300) >> 4)); } /* For resolutions smaller than FP resolution stretch */
--
Ondrej Zary