5832706e8b
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@linux-mips.org>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
91 lines
1.8 KiB
C
91 lines
1.8 KiB
C
/*
|
|
* linux/drivers/video/bt455.h
|
|
*
|
|
* Copyright 2003 Thiemo Seufer <seufer@csv.ica.uni-stuttgart.de>
|
|
* Copyright 2016 Maciej W. Rozycki <macro@linux-mips.org>
|
|
*
|
|
* This file is subject to the terms and conditions of the GNU General
|
|
* Public License. See the file COPYING in the main directory of this
|
|
* archive for more details.
|
|
*/
|
|
#include <linux/types.h>
|
|
|
|
/*
|
|
* Bt455 byte-wide registers, 32-bit aligned.
|
|
*/
|
|
struct bt455_regs {
|
|
volatile u8 addr_cmap;
|
|
u8 pad0[3];
|
|
volatile u8 addr_cmap_data;
|
|
u8 pad1[3];
|
|
volatile u8 addr_clr;
|
|
u8 pad2[3];
|
|
volatile u8 addr_ovly;
|
|
u8 pad3[3];
|
|
};
|
|
|
|
static inline void bt455_select_reg(struct bt455_regs *regs, int ir)
|
|
{
|
|
mb();
|
|
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_next(struct bt455_regs *regs, u8 *grey)
|
|
{
|
|
mb();
|
|
regs->addr_cmap_data;
|
|
rmb();
|
|
*grey = regs->addr_cmap_data & 0xf;
|
|
rmb();
|
|
regs->addr_cmap_data;
|
|
}
|
|
|
|
static inline void bt455_write_cmap_next(struct bt455_regs *regs, u8 grey)
|
|
{
|
|
wmb();
|
|
regs->addr_cmap_data = 0x0;
|
|
wmb();
|
|
regs->addr_cmap_data = grey & 0xf;
|
|
wmb();
|
|
regs->addr_cmap_data = 0x0;
|
|
}
|
|
|
|
static inline void bt455_write_ovly_next(struct bt455_regs *regs, u8 grey)
|
|
{
|
|
wmb();
|
|
regs->addr_ovly = 0x0;
|
|
wmb();
|
|
regs->addr_ovly = grey & 0xf;
|
|
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);
|
|
}
|