Use the address autoincrement feature when accessing successive palette entries and also skip loading a palette address in overlay register assesses which do not use that address. Provide a red/green/blue register sequencer reset helper for use in overlay register assesses where the state of the sequencer is not known. References: [1] "Bt454 Bt455 170 MHz Monolithic CMOS 16 Color Palette RAMDAC", Brooktree Corporation, Document Number: L454001, Rev. I Signed-off-by: Maciej W. Rozycki <macro@xxxxxxxxxxxxxx> --- linux-bt455-cmap-addr.diff Index: linux-20160211-4maxp64/drivers/video/fbdev/bt455.h =================================================================== --- linux-20160211-4maxp64.orig/drivers/video/fbdev/bt455.h +++ linux-20160211-4maxp64/drivers/video/fbdev/bt455.h @@ -30,13 +30,17 @@ static inline void bt455_select_reg(stru regs->addr_cmap = ir & 0x0f; } +static inline void bt455_reset_reg(struct bt455_regs *regs) +{ + mb(); + regs->addr_clr = 0; +} + /* * Read/write to a Bt455 color map register. */ -static inline void bt455_read_cmap_entry(struct bt455_regs *regs, - int cr, u8 *grey) +static inline void bt455_read_cmap_next(struct bt455_regs *regs, u8 *grey) { - bt455_select_reg(regs, cr); mb(); regs->addr_cmap_data; rmb(); @@ -45,10 +49,8 @@ static inline void bt455_read_cmap_entry regs->addr_cmap_data; } -static inline void bt455_write_cmap_entry(struct bt455_regs *regs, - int cr, u8 grey) +static inline void bt455_write_cmap_next(struct bt455_regs *regs, u8 grey) { - bt455_select_reg(regs, cr); wmb(); regs->addr_cmap_data = 0x0; wmb(); @@ -57,10 +59,8 @@ static inline void bt455_write_cmap_entr regs->addr_cmap_data = 0x0; } -static inline void bt455_write_ovly_entry(struct bt455_regs *regs, - int cr, u8 grey) +static inline void bt455_write_ovly_next(struct bt455_regs *regs, u8 grey) { - bt455_select_reg(regs, cr); wmb(); regs->addr_ovly = 0x0; wmb(); @@ -68,3 +68,23 @@ static inline void bt455_write_ovly_entr wmb(); regs->addr_ovly = 0x0; } + +static inline void bt455_read_cmap_entry(struct bt455_regs *regs, + int cr, u8 *grey) +{ + bt455_select_reg(regs, cr); + bt455_read_cmap_next(regs, grey); +} + +static inline void bt455_write_cmap_entry(struct bt455_regs *regs, + int cr, u8 grey) +{ + bt455_select_reg(regs, cr); + bt455_write_cmap_next(regs, grey); +} + +static inline void bt455_write_ovly_entry(struct bt455_regs *regs, u8 grey) +{ + bt455_reset_reg(regs); + bt455_write_ovly_next(regs, grey); +} Index: linux-20160211-4maxp64/drivers/video/fbdev/pmag-aa-fb.c =================================================================== --- linux-20160211-4maxp64.orig/drivers/video/fbdev/pmag-aa-fb.c +++ linux-20160211-4maxp64/drivers/video/fbdev/pmag-aa-fb.c @@ -122,8 +122,8 @@ static int aafb_cursor(struct fb_info *i u8 bg = cursor->image.bg_color ? 0xf : 0x0; bt455_write_cmap_entry(par->bt455, 8, bg); - bt455_write_cmap_entry(par->bt455, 9, bg); - bt455_write_ovly_entry(par->bt455, 0, fg); + bt455_write_cmap_next(par->bt455, bg); + bt455_write_ovly_next(par->bt455, fg); } if (cursor->set & (FB_CUR_SETSIZE | FB_CUR_SETSHAPE | FB_CUR_SETIMAGE)) bt431_set_cursor(par->bt431, @@ -212,7 +212,7 @@ static int pmagaafb_probe(struct device /* Init colormap. */ bt455_write_cmap_entry(par->bt455, 0, 0x0); - bt455_write_cmap_entry(par->bt455, 1, 0xf); + bt455_write_cmap_next(par->bt455, 0xf); /* Init hardware cursor. */ bt431_erase_cursor(par->bt431); -- To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html