From 10ee39fe3ff618d274e1cd0f6abbc2917b736bfd Mon Sep 17 00:00:00 2001 From: Christian Trefzer Date: Tue, 14 Feb 2006 13:53:26 -0800 Subject: [PATCH] neofb: avoid resetting display config on unblank Fix issues with the NeoMagic framebuffer driver. It nicely complements my previous fix already in linus' tree. The only thing missing now is that the external CRT will not be activated at neofb init when external-only is selected, either by register read or module/kernel parameter. Testing was done on a Dell Latitude CPi-A/NM2200 chip. Previous behaviour: - before booting linux, set the preferred display config X via FN+F8 - boot linux, neofb stores the register values in a private variable - change the display config to Y via keystroke - leave the machine in peace until display is blanked - touching any key will result in display config X being restored - booting up, the BIOS will acknowledge config Y, though... Current behaviour: At the time of unblanking, config Y is honoured because we now read back register contents instead of just overwriting them with outdated values. Signed-off by: Christian Trefzer Cc: "Antonino A. Daplas" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/video/neofb.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'drivers/video/neofb.c') diff --git a/drivers/video/neofb.c b/drivers/video/neofb.c index 747602aa5615..b85e2b180a44 100644 --- a/drivers/video/neofb.c +++ b/drivers/video/neofb.c @@ -1334,6 +1334,12 @@ static int neofb_blank(int blank_mode, struct fb_info *info) struct neofb_par *par = info->par; int seqflags, lcdflags, dpmsflags, reg; + /* + * Reload the value stored in the register, might have been changed via + * FN keystroke + */ + par->PanelDispCntlReg1 = vga_rgfx(NULL, 0x20) & 0x03; + switch (blank_mode) { case FB_BLANK_POWERDOWN: /* powerdown - both sync lines down */ seqflags = VGA_SR01_SCREEN_OFF; /* Disable sequencer */ @@ -1366,7 +1372,7 @@ static int neofb_blank(int blank_mode, struct fb_info *info) case FB_BLANK_NORMAL: /* just blank screen (backlight stays on) */ seqflags = VGA_SR01_SCREEN_OFF; /* Disable sequencer */ lcdflags = par->PanelDispCntlReg1 & 0x02; /* LCD normal */ - dpmsflags = 0; /* no hsync/vsync suppression */ + dpmsflags = 0x00; /* no hsync/vsync suppression */ break; case FB_BLANK_UNBLANK: /* unblank */ seqflags = 0; /* Enable sequencer */ -- cgit v1.2.3 From 9f672004ab1a8094bec1785b39ac683ab9eebebc Mon Sep 17 00:00:00 2001 From: Christian Trefzer Date: Wed, 15 Feb 2006 15:17:34 -0800 Subject: [PATCH] neofb: avoid resetting display config on unblank (v2) There were two mistakes in the register-read-on-(un)blank approach. - First, without proper register (un)locking the value read back will always be zero, and this is what I missed entirely until just now. Due to this, the logic could not be verified at all and I tried some bogus checks which are completely stupid. - Second, the LCD status bit will always be set to zero when the backlight has been turned off. Reading the value back during unblank will disable the LCD unconditionally, regardless of the state it is supposed to be in, since we set it to zero beforehand. So this is what we do now: - create a new variable in struct neofb_par, and use that to determine whether to read back registers (initialized to true) - before actually blanking the screen, read back the register to sense any possible change made through Fn key combo - use proper neoUnlock() / neoLock() to actually read something - every call to neofb_blank() determines if we read back next time: blanking disables readback, unblanking (FB_BLANK_UNBLANK) enables it This should give us a nice and clean state machine. Has been thoroughly tested on a Dell Latitude CPiA / NM220 Chip docked to a C/Dock2 with attached CRT in all possible combinations of LCD/CRT on/off. I changed the config via Fn key, let the console blank, unblanked by keypress - works flawlessly. Signed-off-by: Christian Trefzer Cc: "Antonino A. Daplas" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/video/neofb.c | 15 ++++++++++++--- include/video/neomagic.h | 1 + 2 files changed, 13 insertions(+), 3 deletions(-) (limited to 'drivers/video/neofb.c') diff --git a/drivers/video/neofb.c b/drivers/video/neofb.c index b85e2b180a44..a2e201dc40f7 100644 --- a/drivers/video/neofb.c +++ b/drivers/video/neofb.c @@ -843,6 +843,9 @@ static int neofb_set_par(struct fb_info *info) par->SysIfaceCntl2 = 0xc0; /* VESA Bios sets this to 0x80! */ + /* Initialize: by default, we want display config register to be read */ + par->PanelDispCntlRegRead = 1; + /* Enable any user specified display devices. */ par->PanelDispCntlReg1 = 0x00; if (par->internal_display) @@ -1334,11 +1337,17 @@ static int neofb_blank(int blank_mode, struct fb_info *info) struct neofb_par *par = info->par; int seqflags, lcdflags, dpmsflags, reg; + /* - * Reload the value stored in the register, might have been changed via - * FN keystroke + * Reload the value stored in the register, if sensible. It might have + * been changed via FN keystroke. */ - par->PanelDispCntlReg1 = vga_rgfx(NULL, 0x20) & 0x03; + if (par->PanelDispCntlRegRead) { + neoUnlock(); + par->PanelDispCntlReg1 = vga_rgfx(NULL, 0x20) & 0x03; + neoLock(&par->state); + } + par->PanelDispCntlRegRead = !blank_mode; switch (blank_mode) { case FB_BLANK_POWERDOWN: /* powerdown - both sync lines down */ diff --git a/include/video/neomagic.h b/include/video/neomagic.h index 1d69049bd4c1..78b1f15a538f 100644 --- a/include/video/neomagic.h +++ b/include/video/neomagic.h @@ -159,6 +159,7 @@ struct neofb_par { unsigned char PanelDispCntlReg1; unsigned char PanelDispCntlReg2; unsigned char PanelDispCntlReg3; + unsigned char PanelDispCntlRegRead; unsigned char PanelVertCenterReg1; unsigned char PanelVertCenterReg2; unsigned char PanelVertCenterReg3; -- cgit v1.2.3 From 6af7ffc414828cda880a4e99e20f4f07880281e7 Mon Sep 17 00:00:00 2001 From: "Antonino A. Daplas" Date: Sat, 11 Mar 2006 03:27:20 -0800 Subject: [PATCH] neofb: Fix uninitialized value Remove insignificant and unitialized variable "waitcycles" from neo2200_sync. Coverity Bug 895 Signed-off-by: Antonino Daplas Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/video/neofb.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'drivers/video/neofb.c') diff --git a/drivers/video/neofb.c b/drivers/video/neofb.c index a2e201dc40f7..b961d5601bd9 100644 --- a/drivers/video/neofb.c +++ b/drivers/video/neofb.c @@ -486,10 +486,8 @@ static void vgaHWRestore(const struct fb_info *info, static inline int neo2200_sync(struct fb_info *info) { struct neofb_par *par = info->par; - int waitcycles; - while (readl(&par->neo2200->bltStat) & 1) - waitcycles++; + while (readl(&par->neo2200->bltStat) & 1); return 0; } -- cgit v1.2.3